geosfera indonesia published by: department of geography education university of jember e-issn 2614-8528 p-issn 2598-9723 geos. ind. vol. 5 no. 3, december 2020 available online since 30 december 2020 at : https://jurnal.unej.ac.id/index.php/geosi/issue/view/1064 geosfera indonesia published by: department of geography education university of jember e-issn 2614-8528 p-issn 2598-9723 geos. ind. vol. 5 no. 3, december 2020 available online since 30 december 2020 at : https://jurnal.unej.ac.id/index.php/geosi/issue/view/1064 geosfera indonesia published by: department of geography education university of jember e-issn 2614-8528 p-issn 2598-9723 geos. ind. vol. 5 no. 3, december 2020 available online since 30 december 2020 at : https://jurnal.unej.ac.id/index.php/geosi/issue/view/1064 geosfera indonesia, vol. 5 no. 3 (2020) accredited by the ministry of research , technology , and higher education of the republic of indonesia, no. 30/e/kpt/2019 . editorial team editor in chief fahmi arif kurnianto (scopus id: 57208473928) department of geography education, university of jember, indonesia advisory international editorial boards mihai ciprian margarint (scopus id : 36698019400) department of geography, alexandru ioan cuza university of iasi, romania franck lavigne (scopus id : 15738234900) physical geography laboratory, université paris 1 panthéon-sorbonne, france fahrudi ahwan ikhsan (scopus id : 57208469257) department of geography education, university of jember, indonesia mustafa ustuner (scopus id : 56246446800) department of geomatics engineering, yildiz technical university, turkey bashkim idrizi (scopus id : 55937683800) department of geodesy, university "mother teresa" -skopje, macedonia guillermo hector re (scopus id : 7102894803) department of geology, universidad de buenos aires, buenos aires, argentina laras tursilowati (scopus id : 55317967300) indonesian national institute of aeronautics and space (lapan), indonesia kuppanagounder kumaraswamy (scopus id : 6602935596) department of geography, bharathidasan university, tiruchirappalli, india copyright (c) 2020 geosfera indonesia journal and department of geography education, university of jember focus and scope geosfera indonesia welcomes high quality original research articles, short communications, and review articles written by researchers, academicians, professional, and practitioners from all over the world about : (1) geography education : collaborative learning; comparative learning; curriculum; e-learning ; instructional technology; learning community; life skills ; remedial teaching; taxonomy of educational objectives (bloom's taxonomy); new technology; industry and education : a continous collaboration; blended learning; character; constructivist learning; disrupting innovation; expeditionary learning; flexible learning; flipped classroom; flipped learning; gamification; global view; ground up diversity; high-quality teachers; hip-hop education (hiphoped); lesson study; mobile education; problem based learning; process oriented guided inquiry lessons (pogil); project based learning (pbl); start-up; student centred learning; autodidacticism (self-teaching); informal learning; unschooling or homeschooling; pisa task, (2) physical geography : tectonics and regional structure; glacial processes and landforms; fluvial sequences; fluvial processes and landforms; mass movement; hillslopes and soil erosion; slopes processes; karst processes and landforms; aeolian processes and landforms; coastal dunes and arid landforms; coastal and marine processes; theoretical and quantitative geomorphology; soil geomorphology; soil geography; lithology; hydrogeography, (3) human geography : cultural geography; political geography; social geography; population geography; urban geography, (4) geographic information system (gis) : data collection and acquisition; data structures and algorithms; spatio-temporal databases; spatial analysis, data mining, and decision support systems; cartography; location based services; uncertainty handling in spatial data; topology; geo-computation; geo-telematics; spatial information infrastructures; interoperability and open systems; applications of geoinformation technology (all possible domains), (5) remote sensing: multi-spectral and hyperspectral remote sensing; active and passive microwave remote sensing; lidar and laser scanning; geometric reconstruction; physical modeling and signatures; change detection; image processing and pattern recognition; data fusion and data assimilation; dedicated satellite missions; operational processing facilities; spaceborne, airborne and terrestrial platforms; remote sensing applications, (6) environmental science : environmental geography; environmental education; climate change; land use and cover change; pollution; natural resources management; conservation; management and valorisation of waste; development of methods for environmental quality management; environmental system modelling and optimization; environmental analysis and assessment; social, economic and policy aspects of environmental management, (7) disaster risk reduction : risk awareness and assessment including hazard analysis and vulnerability/capacity analysis for natural disaster risk reduction; knowledge development including education, training, research and information for natural disaster risk reduction; public commitment and institutional frameworks, including organisational, policy, legislation and community action for natural disaster risk reduction. publication information secretariat of geosfera indonesia department of geography education, university of jember, fkip building, jl. kalimantan 37, jember, east java, 68121, indonesia. telp. (0331) 334988 / 330738 email : geografi.fkip@unej.ac.id website : https://jurnal.unej.ac.id/index.php/geosi copyright (c) 2020 geosfera indonesia journal and department of geography education, university of jember geosfera indonesia (geos. ind.) : | issn: 2598-9723 (print)| issn: 2614-8528 (online) is an international open access and peer-reviewed journal, published by department of geography education, university of jember, indonesia. its published three times a year in april, august, and december. geosfera indonesia is accredited by the ministry of research, technology and higher education of the republic of indonesia (ristekdikti), no. 30/e/kpt/2019. this journal has been covered by following indexing and abstracting services: (1) cabi : cab abstracts (web of science); (2) directory of open access journal (doaj); (3) ebsco; (4) google scholar (5) one search (national library of republic of indonesia); (6) sinta 2. table of contents the assessment of deforestation impact towards microclimate and environment in ilorin, nigeria 301-317toluwalope mubo agaja, elisha ademola adeleke, enekole esther adeniyi, precious temilade afolayan development of multimedia learning geography based on adobe flash to increase students’ curiosity 318-334 wahid yuda rejeki* and m. mukminan geospatial approach for the analysis of forest cover change detection using machine learning 335-351 r. sanjeeva reddy, g. anjan babu, a. rama mohan reddy emerging geospatial technologies in environmental research, education, and outreach 352-363sergio bernardes, margueritte madden, ashurst walker, andrew knight, nicholas neel, akshay mendki, dhaval bhanderi, andrew guest, shannon healy, thomas jordan a review paper on monitoring environmental consequences of land cover dynamics with the help of geo-informatics technologies copyright (c) 2020 geosfera indonesia journal and department of geography education, university of jember 364-389 ziyad ahmed abdo, satya prakash cover geosfera 5,3.pdf (p.1) geosfera indonesia akred.pdf (p.2) focus and scope.pdf (p.3-4) acknowledgement the editorial board would like to thank and express appreciation to all peer reviewers who have reviewed the manuscripts for publication of geosfera indonesia vol. 5 no. 2, august 2020. marinela istrate (scopus id : 56672996500) department of geography, universitatea alexandru ioan cuza, iasi, romania lucian rosu (scopus id : 56958158800) department of geography, universitatea alexandru ioan cuza, iasi, romania mihai niculita (scopus id : 55022909500) department of geography, alexandru ioan cuza university of iasi, romania tin lukic (scopus id : 54795557700) department of geography, university of novi sad, serbia fatih adiguzel (scopus id : 57204062132) , department of geography, nevşehir haci bektaş veli üniversitesi, nevsehir, turkey elan artono nurdin (scopus id : 57192649049) department of geography education, university of jember, indonesia bejo apriyanto (scopus id : 57208468203) department of geography education, university of jember, indonesia prima widayani (scopus id : 57188879871) faculty of geography, gadjah mada university, indonesia ivan taslim, (scopus id : 57203022349) department of geography, universitas muhammadiyah gorontalo, indonesia efdal kaya, (scopus id : 57202135756) department of architecture and urban planning, iskenderun technical university, iskenderun, turkey batuhan kilic, (scopus id : 57204675825) geomatic engineering department, yildiz technical university, istanbul, turkey nailul insani, (scopus id : 57208471498) department of geography, universitas negeri malang, indonesia rendra zainal maliki department of geography education, universitas tadulako, indonesia https://www.scopus.com/authid/detail.uri?authorid=56672996500 https://www.scopus.com/authid/detail.uri?authorid=56958158800 https://www.scopus.com/authid/detail.uri?authorid=55022909500 https://www.scopus.com/authid/detail.uri?authorid=54795557700 https://www.scopus.com/authid/detail.uri?authorid=57204062132 https://www.scopus.com/authid/detail.uri?authorid=57192649049 https://www.scopus.com/authid/detail.uri?authorid=57208468203 https://www.scopus.com/authid/detail.uri?authorid=57188879871 https://www.scopus.com/authid/detail.uri?authorid=57203022349 https://www.scopus.com/authid/detail.uri?authorid=57202135756 https://www.scopus.com/authid/detail.uri?authorid=57204675825 https://www.scopus.com/authid/detail.uri?authorid=57208471498 https://scholar.google.co.id/citations?user=qivrcmkaaaaj&hl=id geos geosfera indonesia geosfera indonesia (journal initial : geosi, journal abbreviation : geos. ind.) : issn: 2598-9723 (print) ; issn: 26148528 (online) is an international open access and peer-reviewed journal, published by department of geography education, university of jember, indonesia. geosfera indonesia welcomes high quality original research articles, short communications, and review articles written by researchers, academicians, professional, and practitioners from all over the world about : (1) geography education, (2) geography (physical geography and human geography), (3) geographic information system (gis), (4) remote sensing, (5) environmental science, and (6) disaster risk reduction. it is published three times a year in april, august, and december. geosfera indonesia is accredited by the ministry of research, technology and higher education of the republic of indonesia (ristekdikti), no. 30/e/kpt/2019 (20172022). indexed by : geosfera indonesia published by: department of geography education university of jember e-issn 2614-8528 p-issn 2598-9723 geos. ind. vol. 5 no. 2, august 2020 available online since 1 june 2020 at : https://jurnal.unej.ac.id/index.php/geosi/issue/view/952 geosfera indonesia published by: department of geography education university of jember e-issn 2614-8528 p-issn 2598-9723 geos. ind. vol. 5 no. 2, august 2020 available online since 1 june 2020 at : https://jurnal.unej.ac.id/index.php/geosi/issue/view/952 geosfera indonesia published by: department of geography education university of jember e-issn 2614-8528 p-issn 2598-9723 geos. ind. vol. 5 no. 2, august 2020 available online since 1 june 2020 at : https://jurnal.unej.ac.id/index.php/geosi/issue/view/952 geosfera indonesia, vol. 5 no. 2 (2020) accredited by the ministry of research , technology , and higher education of the republic of indonesia, no. 30/e/kpt/2019 . editorial team editor in chief fahmi arif kurnianto (scopus id: 57208473928) department of geography education, university of jember, indonesia advisory international editorial boards mihai ciprian margarint (scopus id : 36698019400) department of geography, alexandru ioan cuza university of iasi, romania franck lavigne (scopus id : 15738234900) physical geography laboratory, université paris 1 panthéon-sorbonne, france fahrudi ahwan ikhsan (scopus id : 57208469257) department of geography education, university of jember, indonesia mustafa ustuner (scopus id : 56246446800) department of geomatics engineering, yildiz technical university, turkey bashkim idrizi (scopus id : 55937683800) department of geodesy, university "mother teresa" -skopje, macedonia guillermo hector re (scopus id : 7102894803) department of geology, universidad de buenos aires, buenos aires, argentina laras tursilowati (scopus id : 55317967300) indonesian national institute of aeronautics and space (lapan), indonesia kuppanagounder kumaraswamy (scopus id : 6602935596) department of geography, bharathidasan university, tiruchirappalli, india copyright (c) 2020 geosfera indonesia journal and department of geography education, university of jember focus and scope geosfera indonesia welcomes high quality original research articles, short communications, and review articles written by researchers, academicians, professional, and practitioners from all over the world about : (1) geography education : collaborative learning; comparative learning; curriculum; e-learning ; instructional technology; learning community; life skills ; remedial teaching; taxonomy of educational objectives (bloom's taxonomy); new technology; industry and education : a continous collaboration; blended learning; character; constructivist learning; disrupting innovation; expeditionary learning; flexible learning; flipped classroom; flipped learning; gamification; global view; ground up diversity; high-quality teachers; hip-hop education (hiphoped); lesson study; mobile education; problem based learning; process oriented guided inquiry lessons (pogil); project based learning (pbl); start-up; student centred learning; autodidacticism (self-teaching); informal learning; unschooling or homeschooling; pisa task, (2) physical geography : tectonics and regional structure; glacial processes and landforms; fluvial sequences; fluvial processes and landforms; mass movement; hillslopes and soil erosion; slopes processes; karst processes and landforms; aeolian processes and landforms; coastal dunes and arid landforms; coastal and marine processes; theoretical and quantitative geomorphology; soil geomorphology; soil geography; lithology; hydrogeography, (3) human geography : cultural geography; political geography; social geography; population geography; urban geography, (4) geographic information system (gis) : data collection and acquisition; data structures and algorithms; spatio-temporal databases; spatial analysis, data mining, and decision support systems; cartography; location based services; uncertainty handling in spatial data; topology; geo-computation; geo-telematics; spatial information infrastructures; interoperability and open systems; applications of geoinformation technology (all possible domains), (5) remote sensing: multi-spectral and hyperspectral remote sensing; active and passive microwave remote sensing; lidar and laser scanning; geometric reconstruction; physical modeling and signatures; change detection; image processing and pattern recognition; data fusion and data assimilation; dedicated satellite missions; operational processing facilities; spaceborne, airborne and terrestrial platforms; remote sensing applications, (6) environmental science : environmental geography; environmental education; climate change; land use and cover change; pollution; natural resources management; conservation; management and valorisation of waste; development of methods for environmental quality management; environmental system modelling and optimization; environmental analysis and assessment; social, economic and policy aspects of environmental management, (7) disaster risk reduction : risk awareness and assessment including hazard analysis and vulnerability/capacity analysis for natural disaster risk reduction; knowledge development including education, training, research and information for natural disaster risk reduction; public commitment and institutional frameworks, including organisational, policy, legislation and community action for natural disaster risk reduction. publication information secretariat of geosfera indonesia department of geography education, university of jember, fkip building, jl. kalimantan 37, jember, east java, 68121, indonesia. telp. (0331) 334988 / 330738 email : geografi.fkip@unej.ac.id website : https://jurnal.unej.ac.id/index.php/geosi copyright (c) 2020 geosfera indonesia journal and department of geography education, university of jember geosfera indonesia (geos. ind.) : | issn: 2598-9723 (print)| issn: 2614-8528 (online) is an international open access and peer-reviewed journal, published by department of geography education, university of jember, indonesia. its published three times a year in april, august, and december. geosfera indonesia is accredited by the ministry of research, technology and higher education of the republic of indonesia (ristekdikti), no. 30/e/kpt/2019. this journal has been covered by following indexing and abstracting services: (1) cabi : cab abstracts (web of science); (2) directory of open access journal (doaj); (3) ebsco; (4) google scholar (5) one search (national library of republic of indonesia); (6) sinta 2. table of contents a new algorithm for the grid cell-based runoff routing model based on travel time concept 160-185 baina afkril, m. pramono hadi, slamet suprayogi a preliminary study on tsunami disaster in yogyakarta: identification of vulnerability order and components 186-195 lina wahyuni, muh. aris marfai, m. pramono hadi soil zonation and the shaking table test of the embankment on clayey soil 196-209 ripon hore, sudipta chakraborty, md. fayjul bari, ayaz mahmud shuvon, mehedi ahmed ansary modeling land use and land cover dynamic using geographic information system and markov-ca 210-225 millary agung widiawaty, arif ismail, moh. dede, n. nurhanifah spatio-statistical analysis of rainfall and temperature distribution, anomaly and trend in nigeria 226-249 elisha ademola adeleke and eniola aminat orebayo the facies and metamorphism types determination of metamorphic rock in the part of mekongga complex 268-287 m. musnajam, ahmad tarmizi abd karim , n. nurfadillah, fahrudi ahwan ikhsan, andri estining sejati building density level of urban slum area in jakarta tenty melvianti legarias , renny nurhasana, edy irwansyah land value potential zonation : implication towards urban planning 288-300 revi mainaki, anita eka putri, dwiyono hari utomo copyright (c) 2020 geosfera indonesia journal and department of geography education, university of jember 250-267 cover geosfera 5,2 malam.pdf (p.1) geosfera indonesia akredcover.pdf (p.2) focus and scope2.pdf (p.3-4) acknowledgement the editorial board would like to thank and express appreciation to all peer reviewers who have reviewed the manuscripts for publication of geosfera indonesia. marinela istrate (scopus id : 56672996500) department of geography, universitatea alexandru ioan cuza, iasi, romania lucian rosu (scopus id : 56958158800) department of geography, universitatea alexandru ioan cuza, iasi, romania mihai niculita (scopus id : 55022909500) department of geography, alexandru ioan cuza university of iasi, romania tin lukic (scopus id : 54795557700) department of geography, university of novi sad, serbia fatih adiguzel (scopus id : 57204062132) , department of geography, nevşehir haci bektaş veli üniversitesi, nevsehir, turkey elan artono nurdin (scopus id : 57192649049) department of geography education, university of jember, indonesia bejo apriyanto (scopus id : 57208468203) department of geography education, university of jember, indonesia prima widayani (scopus id : 57188879871) faculty of geography, gadjah mada university, indonesia ivan taslim (scopus id : 57203022349) department of geography, universitas muhammadiyah gorontalo, indonesia efdal kaya (scopus id : 57202135756) department of architecture and urban planning, iskenderun technical university, iskenderun, turkey batuhan kilic (scopus id : 57204675825) geomatic engineering department, yildiz technical university, istanbul, turkey nailul insani (scopus id : 57208471498) department of geography, universitas negeri malang, indonesia rendra zainal maliki department of geography education, universitas tadulako, indonesia faisal arif setiawan department of geography education, universitas lambung mangkurat, indonesia aulia ulfa farahdiba (scopus id : 57208130620) , department of environmental engineering, universitas pembangunan nasional "veteran" jawa timur, indonesia guruh samodra (scopus id : 55053491600) faculty of geography, universitas gadjah mada, yogyakarta, indonesia andri estining sejati (scopus id : 57211280452) geography education study program, universitas sembilanbelas november, kolaka, indonesia wahid akhsin budi nur sidiq (scopus id : 57201676728), department of geography, universitas negeri semarang, semarang indonesia pertiwi andarani (scopus id : 55959123900), department of environmental engineering, universitas diponegoro, semarang, indonesia prama ardha aryaguna (scopus id : 56236908900), department of survey and mapping, faculty of engineering, universitas esa unggul, jakarta, indonesia ionuț minea (scopus id : 56951000900), faculty of geography and geology, department of geography, alexandru ioan cuza university, 20 a, carol i bd., 700505 iasi, romania rosmadi fauzi (scopus id : 6508044388), department of geography, university of malaya, kuala lumpur, malaysia geos geosfera indonesia geosfera indonesia (journal initial : geosi, journal abbreviation : geos. ind.) : issn: 2598-9723 (print) ; issn: 26148528 (online) is an international open access and peer-reviewed journal, published by department of geography education, university of jember, indonesia. geosfera indonesia welcomes high quality original research articles, short communications, and review articles written by researchers, academicians, professional, and practitioners from all over the world about : (1) geography education, (2) geography (physical geography and human geography), (3) geographic information system (gis), (4) remote sensing, (5) environmental science, and (6) disaster risk reduction. it is published three times a year in april, august, and december. geosfera indonesia is accredited (sinta 2) by the ministry of research and technology of the republic of indonesia (ristekbrin), no. 200/m/kpt/2020 (2020-2025). indexed by : geos geosfera indonesia geosfera indonesia (journal initial : geosi, journal abbreviation : geos. ind.) : issn: 2598-9723 (print) ; issn: 26148528 (online) is an international open access and peer-reviewed journal, published by department of geography education, university of jember, indonesia. geosfera indonesia welcomes high quality original research articles, short communications, and review articles written by researchers, academicians, professional, and practitioners from all over the world about : (1) geography education, (2) geography (physical geography and human geography), (3) geographic information system (gis), (4) remote sensing, (5) environmental science, and (6) disaster risk reduction. it is published three times a year in april, august, and december. geosfera indonesia is accredited (sinta 2) by the ministry of research and technology of the republic of indonesia (ristekbrin), no. 200/m/kpt/2020 (2020-2025). indexed by : geos geosfera indonesia geosfera indonesia (journal initial : geosi, journal abbreviation : geos. ind.) : issn: 2598-9723 (print) ; issn: 26148528 (online) is an international open access and peer-reviewed journal, published by department of geography education, university of jember, indonesia. geosfera indonesia welcomes high quality original research articles, short communications, and review articles written by researchers, academicians, professional, and practitioners from all over the world about : (1) geography education, (2) geography (physical geography and human geography), (3) geographic information system (gis), (4) remote sensing, (5) environmental science, and (6) disaster risk reduction. it is published three times a year in april, august, and december. geosfera indonesia is accredited (sinta 2) by the ministry of research and technology of the republic of indonesia (ristekbrin), no. 200/m/kpt/2020 (2020-2025). indexed by : acknowledgement the editorial board would like to thank and express appreciation to all peer reviewers who have reviewed the manuscripts for publication of geosfera indonesia. marinela istrate (scopus id : 56672996500) department of geography, universitatea alexandru ioan cuza, iasi, romania lucian rosu (scopus id : 56958158800) department of geography, universitatea alexandru ioan cuza, iasi, romania mihai niculita (scopus id : 55022909500) department of geography, alexandru ioan cuza university of iasi, romania tin lukic (scopus id : 54795557700) department of geography, university of novi sad, serbia fatih adiguzel (scopus id : 57204062132) , department of geography, nevşehir haci bektaş veli üniversitesi, nevsehir, turkey elan artono nurdin (scopus id : 57192649049) department of geography education, university of jember, indonesia bejo apriyanto (scopus id : 57208468203) department of geography education, university of jember, indonesia prima widayani (scopus id : 57188879871) faculty of geography, gadjah mada university, indonesia ivan taslim, (scopus id : 57203022349) department of geography, universitas muhammadiyah gorontalo, indonesia efdal kaya, (scopus id : 57202135756) department of architecture and urban planning, iskenderun technical university, iskenderun, turkey batuhan kilic, (scopus id : 57204675825) geomatic engineering department, yildiz technical university, istanbul, turkey nailul insani, (scopus id : 57208471498) department of geography, universitas negeri malang, indonesia rendra zainal maliki department of geography education, universitas tadulako, indonesia faisal arif setiawan department of geography education, universitas lambung mangkurat, indonesia geos geosfera indonesia geosfera indonesia (journal initial : geosi, journal abbreviation : geos. ind.) : issn: 2598-9723 (print) ; issn: 26148528 (online) is an international open access and peer-reviewed journal, published by department of geography education, university of jember, indonesia. geosfera indonesia welcomes high quality original research articles, short communications, and review articles written by researchers, academicians, professional, and practitioners from all over the world about : (1) geography education, (2) geography (physical geography and human geography), (3) geographic information system (gis), (4) remote sensing, (5) environmental science, and (6) disaster risk reduction. it is published three times a year in april, august, and december. geosfera indonesia is accredited by the ministry of research, technology and higher education of the republic of indonesia (ristekdikti), no. 30/e/kpt/2019 (20172022). indexed by : geos geosfera indonesia geosfera indonesia (journal initial : geosi, journal abbreviation : geos. ind.) : issn: 2598-9723 (print) ; issn: 26148528 (online) is an international open access and peer-reviewed journal, published by department of geography education, university of jember, indonesia. geosfera indonesia welcomes high quality original research articles, short communications, and review articles written by researchers, academicians, professional, and practitioners from all over the world about : (1) geography education, (2) geography (physical geography and human geography), (3) geographic information system (gis), (4) remote sensing, (5) environmental science, and (6) disaster risk reduction. it is published three times a year in april, august, and december. geosfera indonesia is accredited by the ministry of research, technology and higher education of the republic of indonesia (ristekdikti), no. 30/e/kpt/2019 (20172022). indexed by : geos geosfera indonesia geosfera indonesia (journal initial : geosi, journal abbreviation : geos. ind.) : issn: 2598-9723 (print) ; issn: 26148528 (online) is an international open access and peer-reviewed journal, published by department of geography education, university of jember, indonesia. geosfera indonesia welcomes high quality original research articles, short communications, and review articles written by researchers, academicians, professional, and practitioners from all over the world about : (1) geography education, (2) geography (physical geography and human geography), (3) geographic information system (gis), (4) remote sensing, (5) environmental science, and (6) disaster risk reduction. it is published three times a year in april, august, and december. geosfera indonesia is accredited by the ministry of research, technology and higher education of the republic of indonesia (ristekdikti), no. 30/e/kpt/2019 (20172022). indexed by : geosfera indonesia published by: department of geography education university of jember e-issn 2614-8528 p-issn 2598-9723 geos. ind. vol. 6 no. 1, april 2021 available online since 25 april 2021 at : https://jurnal.unej.ac.id/index.php/geosi geosfera indonesia published by: department of geography education university of jember e-issn 2614-8528 p-issn 2598-9723 geos. ind. vol. 6 no. 1, april 2021 available online since 25 april 2021 at : https://jurnal.unej.ac.id/index.php/geosi geosfera indonesia published by: department of geography education university of jember e-issn 2614-8528 p-issn 2598-9723 geos. ind. vol. 6 no. 1, april 2021 available online since 25 april 2021 at : https://jurnal.unej.ac.id/index.php/geosi geosfera indonesia, vol. 6 no. 1 (2021) accredited (sinta 2) by the ministry of research and technology of the republic of indonesia (ristekbrin), no. 200/m/kpt/2020 . editorial team editor in chief fahmi arif kurnianto (scopus id: 57208473928) department of geography education, university of jember, indonesia advisory international editorial boards mihai ciprian margarint (scopus id : 36698019400) department of geography, alexandru ioan cuza university of iasi, romania fahrudi ahwan ikhsan (scopus id : 57208469257) department of geography education, university of jember, indonesia mustafa ustuner (scopus id : 56246446800) department of geomatics engineering, yildiz technical university, turkey bashkim idrizi (scopus id : 55937683800) department of geodesy, university "mother teresa" -skopje, macedonia guillermo hector re (scopus id : 7102894803) department of geology, universidad de buenos aires, buenos aires, argentina laras tursilowati (scopus id : 55317967300) indonesian national institute of aeronautics and space (lapan), indonesia m. asyroful mujib (scopus id : 57217104177) department of geography education, university of jember, indonesia lyubka pashova (scopus id : 6506546577) national institute of geophysics, geodesy and geography, bulgarian academy of sciencesdisabled, sofia, bulgaria layout editors yucha risdarani (department of geography education, university of jember, indonesia) m. mitasari (department of geography education, university of jember, indonesia) giofani ginolla ardiyanto (department of geography education, university of jember, indonesia) copyright (c) 2021 geosfera indonesia and department of geography education, university of jember https://drive.google.com/file/d/1qarud7btkxdsqlrwobcji-eacl76rta8/view?usp=sharing https://www.scopus.com/authid/detail.uri?authorid=57208473928 https://www.scopus.com/authid/detail.uri?authorid=36698019400 https://www.scopus.com/authid/detail.uri?authorid=57208469257 https://www.scopus.com/authid/detail.uri?authorid=56246446800 https://www.scopus.com/authid/detail.uri?authorid=55937683800 https://www.scopus.com/authid/detail.uri?authorid=7102894803 https://www.scopus.com/authid/detail.uri?authorid=55317967300 https://www.scopus.com/authid/detail.uri?authorid=57217104177 https://www.scopus.com/authid/detail.uri?authorid=6506546577 focus and scope geosfera indonesia welcomes high quality original research articles, short communications, and review articles written by researchers, academicians, professional, and practitioners from all over the world about : (1) geography education : collaborative learning; comparative learning; curriculum; e-learning ; instructional technology; learning community; life skills ; remedial teaching; taxonomy of educational objectives (bloom's taxonomy); new technology; industry and education : a continous collaboration; blended learning; character; constructivist learning; disrupting innovation; expeditionary learning; flexible learning; flipped classroom; flipped learning; gamification; global view; ground up diversity; high-quality teachers; hip-hop education (hiphoped); lesson study; mobile education; problem based learning; process oriented guided inquiry lessons (pogil); project based learning (pbl); start-up; student centred learning; autodidacticism (self-teaching); informal learning; unschooling or homeschooling; pisa task, (2) physical geography : tectonics and regional structure; glacial processes and landforms; fluvial sequences; fluvial processes and landforms; mass movement; hillslopes and soil erosion; slopes processes; karst processes and landforms; aeolian processes and landforms; coastal dunes and arid landforms; coastal and marine processes; theoretical and quantitative geomorphology; soil geomorphology; soil geography; lithology; hydrogeography, (3) human geography : cultural geography; political geography; social geography; population geography; urban geography, (4) geographic information system (gis) : data collection and acquisition; data structures and algorithms; spatio-temporal databases; spatial analysis, data mining, and decision support systems; cartography; location based services; uncertainty handling in spatial data; topology; geo-computation; geo-telematics; spatial information infrastructures; interoperability and open systems; applications of geoinformation technology (all possible domains), (5) remote sensing: multi-spectral and hyperspectral remote sensing; active and passive microwave remote sensing; lidar and laser scanning; geometric reconstruction; physical modeling and signatures; change detection; image processing and pattern recognition; data fusion and data assimilation; dedicated satellite missions; operational processing facilities; spaceborne, airborne and terrestrial platforms; remote sensing applications, (6) environmental science : environmental geography; environmental education; climate change; land use and cover change; pollution; natural resources management; conservation; management and valorisation of waste; development of methods for environmental quality management; environmental system modelling and optimization; environmental analysis and assessment; social, economic and policy aspects of environmental management, (7) disaster risk reduction : risk awareness and assessment including hazard analysis and vulnerability/capacity analysis for natural disaster risk reduction; knowledge development including education, training, research and information for natural disaster risk reduction; public commitment and institutional frameworks, including organisational, policy, legislation and community action for natural disaster risk reduction. publication information geosfera indonesia (geos. ind.) : | issn: 2598-9723 (print)| issn: 2614-8528 (online) is an international open access and peer-reviewed journal, published by department of geography education, university of jember, indonesia. its published three times a year in april, august, and december. geosfera indonesia is accredited (sinta 2) by the ministry of research and technology of the republic of indonesia (ristekbrin), no. 200/m/kpt/2020. this journal has been covered by following indexing and abstracting services: (1) cabi : cab abstracts ; (2) directory of open access journal (doaj); (3) ebsco; (4) google scholar (5) one search (national library of republic of indonesia), (6) web of science. secretariat of geosfera indonesia department of geography education, university of jember, fkip building, jl. kalimantan 37, jember, east java, 68121, indonesia. telp. (0331) 334988 / 330738 email : geografi.fkip@unej.ac.id website : https://jurnal.unej.ac.id/index.php/geosi copyright (c) 2021 geosfera indonesia and department of geography education, university of jember table of contents rethinking urbanization: a transit-information-communication – technology-oriented development path for the developing countries and post-industrial towns 1-19 schuman lam, heng li, ann t.w. yu landslide hazard analysis using a multilayered approach based on various input data configurations 20-39 ilyas ahmad huqqani, tay lea tien, junita mohamad-saleh quantifying the significance of distance to temporal dynamics of covid-19 cases in nigeria using a geographic information system 40-54 ifeyinwa sarah obuekwe, umar saleh anka, sodiq opeyemi ibrahim, usman ahmad adam assessment of water balance at mayang watershed, east java 55-76ariska mia christiwarda sihombing, indarto indarto, sri wahyuningsih development of web-based gis alert system for informing environmental risk of dengue infections in major cities of pakistan 77-95 naureen zainab, aqil tariq, saima siddiqui 96-126 assessing the impacts of climate variability on rural households in agricultural land through the application of livelihood vulnerability index ginjo gitima, abiyot legesse, dereje biru copyright (c) 2021 geosfera indonesia and department of geography education, university of jember cover geosfera 61rev.pdf (p.1) 1.pdf (p.2) focus and scoperev.pdf (p.3-4) sri rahayu et al / geosi vol 4 no 3 (2019) 291-301 291 the effect of google earth utilization on students' spatial thinking ability sri rahayu, murjainah, m. idris department of geography education, university of pgri palembang jln. jend. a. yani, lr gotong royong 9/10 ulu, 30116, palembang, indonesia email : srirahayu9796@gmail.com received 1 august 2019/ revised 2 december 2019/ accepted 5 december 2019/ published 12 december 2019 abstract the ability to think spatially in geography learning is essential, so it requires technology-based learning resources in the form of google earth, which can facilitate students in imagining or visualizing images in mind. in this regard, this study aims to determine the effect of the use of google earth on the spatial thinking abilities of students in the class x geography of sma pgri 2 palembang. this study used an experimental research method (posttest-only control design), because this design is suitable to use if the pre-test is not possible or pre-test can influence the experimental. the sample data collection technique uses purposive sampling, which is based on considerations or criteria that must be met by the sample used in the study. the sample in this study is class x ips 1 as the experimental class and x ips 2 as the control class. data collection techniques used documentation and tests. for data analysis techniques, normality test, homogeneity test, and hypothesis testing using the ibm spss statistics 20 formula for windows. based on the results of the study, the average value of the experimental class's superior post-test was 82.92, and the results of the posttest control class were 66.39. it shows that there are differences in the spatial thinking ability of the experimental group students who were treated using google earth during the learning process. the significance of the results of the posttest t-test from the two experimental and control groups was 0.000, and then the null hypothesis ho was declared rejected because based on the t-test criteria, the significance value was <0.05 or the sig (2-tailed) value of 0,000 was obtained <0.05. so it can be concluded that there is a significant influence between the use of google earth on the spatial thinking ability of students in the class x geography subject of sma pgri 2 palembang. keywords: google earth, spatial thinking ability, geography. 1. introduction spatial thinking is recognized as a collection of three cognitive skills about the nature and concepts of space (such as distance, closeness, and distribution), about the representation of spatial information (such as maps and graphs), and the process of spatial reasoning (such as decision making) (support committee for thinking thinking spatial; liu, et al. 2019). spatial geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.4 no. 3 (2019), 291-301, december, 2019 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v4i3.13350 accredited by the ministry of research, technology and higher education of the republic of indonesia, no. 30/e/kpt/2019. https://jurnal.unej.ac.id/index.php/geosi https://drive.google.com/file/d/1rsnvas6cuhowhl5bj87cl2l6k5dqz7s6/view sri rahayu et al / geosi vol 4 no 3 (2019) 291-301 292 ability according to albert and golledge; setiawan (2015) consists of spatial visualization, spatial orientation and spatial relationships. in fact, according to golledge & stimson; halpern; aliman, mutia & yustesia (2018) spatial thinking is the ability of human reasoning to recognize spaces that can develop due to input, processing and output processes. according to the national research council, 2006; setiawan (2015) spatial thinking is one form of thought among other types of view, such as verbal, logical, statistical, hypothetical and so on. furthermore, spatial thinking is an important character in geography learning activities. according to setiawan (2015), the study of geographic phenomena not only explains the existence of a phenomenon and the process of occurrence of this phenomenon on the surface of the earth but also the shape, size, direction, pattern of phenomena and their relationship with other phenomena. according to hidayat et al (2017), spatial thinking is a basic skill that can be accessed by everyone to different degrees in different contexts to solve problems in various contexts. meanwhile according to lee jongwon & bednars s robert; hidayat et al (2017) spatial thinking requires three related components, namely: the concept of space, the method used to represent spatial information, and the process of spatial reasoning. therefore, these three components are interrelated, mutually supportive and inseparable. the importance of spatial thinking can and must be taught at all levels in the education system. the goal is that each individual has the good spatial ability. gersmehl & gersmehl; oktavianto et al (2017) define spatial thinking as an ability that can be used by a geographer to analyze spatial relationships on earth. this ability will be very useful for students when deciding or making decisions from things that are very simple to complications related to space or location. when someone travels, he must know about distance and direction, so he can predict the time of arrival and not get lost. therefore, in learning geography, it is very important to emphasize spatial thinking, not only information about geographic phenomena, but students must have the ability to analyze spatial aspects, because the ability of spatial thinking in geography can affect students' ability to imagine or visualize images in the mind. based on data obtained from geography subject teachers in class x sma pgri 2 palembang, said that there were 4 class x social studies, where 60% of students in grade 10 had reached kkm with a score above 70, while 40% of students had not yet reached kkm. core competencies of geography subject in class x are managing, reasoning, and presenting in the abstract realm related to the development of what is learned in schools independently and can sri rahayu et al / geosi vol 4 no 3 (2019) 291-301 293 use methods that are following curriculum rules. the basic competency used is to present the results of an analysis of the relationship between humans and their environment as the influence of atmospheric dynamics in the form of narratives, tables, graphs, graphs, illustrated images, and concept maps. then, indicators identify the type of inland waters, identify the use of inland waters, analyze conservation of inland waters, and watersheds. a watershed is a part of the earth's surface where water flows into certain rivers. in other words, a watershed is a rainwater reservoir that enters the watershed. watershed consists of 3 types, namely upstream, downstream and middle watersheds. in this connection, the teacher's role becomes important in learning to improve students' spatial abilities. the teacher is expected to be able to provide stimulation to students and interesting innovations and learning strategies are needed so that students can understand the geography concept about watersheds in southern sumatera, so that it can be understood more easily. recognizing that all technological facilities are needed, that can improve spatial thinking skills. so, it is needs technology that can support learning, using google earth. according to yousman (2008) google earth is an interactive mapping application released by google. google earth displays globe maps, topography, satellite photos, terrain that can be overlaid with roads, buildings, locations, or other geographical information. with google earth, we can plan trips, find tourist attractions, motorbikes, restaurants, hotels, hospitals, schools and more where we can get latitude and longitude coordinates. google earth can display low-resolution satellite photos that depict mountains, seas, forests, to high-resolution satellite photos that can depict objects such as roads, office homes. for certain areas that are already equipped with 3d building views. google earth provides an application for educators to display images of the earth visually. google earth also provides opportunities for students to see every side of the world. google earth helps students see distance and other geographical features. google earth is a free software package available for anyone who has a computer and an internet connection. this is an online resource available in the classroom and can be used by students at home. studies have shown that the use of online resources has helped increase students' understanding of key concepts and skills while also helping students gain confidence in their knowledge of geographical problems (solem and gersmehl; cuviello, 2010). according to bodzin et al. (2009); oktavianto et al. (2017) geospatial-based sites such as google earth can accelerate the improvement of spatial thinking skills in a variety of students. this is in line with the main material in this study that sri rahayu et al / geosi vol 4 no 3 (2019) 291-301 294 requires digital technology facilities with easy access to information that is relatively faster without having to be present directly on the object to be addressed. the novelty in this study is analysis regarding google earth for conveying material taught specifically in geography. bearing in mind that many students find it difficult to understand an object or map if they learn to use ordinary maps, so the teacher is required to more attention for help students develop their own spatial thinking skills so as to achieve the expected competencies in learning geography in school. based on these problems, the reference for researcher to conducting research on the effect of using google earth to students' spatial thinking abilities. the purpose of this study was to determine the effect of using google earth to students' spatial thinking abilities. 2. methods the method used in this study is the experimental research method in the form of posttest only control design (sugiyono, 2010). data collection of this study uses test techniques. the test is given at the end of the meeting, used to obtain data on the ability of students to solve the questions given after using google earth. the test used is a multiple-choice form test.validity test using the ibm spss statistics 20 formula for windows. testing the validity of the instrument in this study uses the validity of construction, namely the pearson productmoment correlation formula as follows: rxy = 𝑛𝛴𝑋𝑌‐(𝛴𝑋)(𝛴𝑌) √{(𝛴𝑋2)‐(𝛴𝑋)2}{𝑁𝛴𝑌2‐(𝛴𝑌)2} (1) (arikunto,2010) reliability testing is done using ibm spss statistics 20 for windows with the cronbach's alpha model, which is measured on the cronbach's alpha scale 0 to 1. to find the reliability value using alpha formula: (arikunto,2010) the data analysis technique used in this study is the statistical test parameter t (t test). the t statistical test is used to test the rejection or acceptance of the null hypothesis, provided that the sample is homogeneous and normally distributed. the value of the geography learning test (2) http://1.bp.blogspot.com/-1itfstw-fbw/udeqtuw1ayi/aaaaaaaaaio/47lrmv2ymcw/s1600/reliabilitas.jpg sri rahayu et al / geosi vol 4 no 3 (2019) 291-301 295 results obtained in the experimental class and the control class. according to sudjana test t-test (2005) as follows: (sudjana, 2005) normality test to analyze data by testing whether the data obtained is normal or not. data normality test needs to be done to find out whether the data analyzed is normal or not. data is said to be normal if the km price is located between 1 (-1≤ km ≤ 1). the data created in the frequency distribution table is tested for normality using the curve slope normality test formula as follows: km = 𝑋 − 𝑀𝑜 𝑆 homogeneity test data is done to prove the similarity of group variance, where samples taken are from the same population. to test the sample using the bertlett test with the chi-square equation. at the beginning of the meeting in the experimental class, students look confused in the following learning because the delivery of learning has never used google earth so that the beginning of learning researchers are active to guide students during the learning process by using google earth. after researchers explain how to use google earth, students become more active. the use of google earth helps researchers in delivering material well so that students become more focused on visualizing images. the water inland described by researchers in the form of rivers, lakes and swamps makes students interested in listening carefully. this is proven by the good results when students work on the posttest. while in the control class applying learning using conventional methods, in this class, students are asked to pay attention to the explanations of researchers with conventional methods, without using google earth, so that makes students bored and tired. students only get information from the teacher. some students ask questions, but many students are passive during the learning process. so it is not enough to pay more attention to assist students in developing sgab = √ (𝑛₁‐1)𝑆1 2+ (𝑛21)𝑆1 2 𝑛1+𝑛2−2 (3) (4) sri rahayu et al / geosi vol 4 no 3 (2019) 291-301 296 spatial thinking skills and cause understanding of the material in the control class can not be maximized, this is seen from the results of students' posttest. this study uses two data collection techniques, namely, documentation and test techniques. the test questions that were given in the sample class had previously been tested for validity and reliability. test questions are given as many as 20 multiple-choice questions. the question is made by adjusting the indicators of spatial thinking ability consisting of location, condition, connection, comparison, aura, region, hierarchy, transition, analogy, pattern, spatial association. 3. results and discussion tests are given at the end of learning (posttest). meanwhile, documentation is used to support research data in the form of test result data and learning documentation. the results of the experimental and control class posttest can be seen in figure 1 below. figure 1. post test results students in the experimental and control classes based on figure 1. shows that in the experimental class and the control class gets a variety of values. however, in the control class, many students received grades at intervals of 5565, and none of the students received grades at intervals of 88-98. students in the experimental class get the highest value of 95, the lowest value of 65, and the average value obtained by the 0 5 10 15 20 25 55-65 66-76 77-87 88-98 experiment class control class sri rahayu et al / geosi vol 4 no 3 (2019) 291-301 297 experimental class is 82.92. meanwhile, the control class test results with the highest score of 85, the lowest score of 55 and the average value obtained by the control class is 66.39. this is proof that the results of experimental class tests using google earth can affect student learning outcomes. in contrast, verma and estaville; jo and hong (2018) revealed that currently, there is no evidence of empirical research that shows that learning geography helps students develop spatial thinking skills. to find out whether the data is normally distributed or not, then the normality test is done using shapiro wilk, with the help of a computer with the statistical package for social science (spss) version 20. the data criteria are said to be normal if significance> 0.05. the results of data processing using the shapiro wilk technique can be seen in table 1 below. table 1. distribution of normality test results with the shapiro wilk test class kolmogorovsmirnova shapiro-wilk statistic df sig. statistic df sig. spatial thinking ability posttest experimen .131 36 .123 .945 36 .073 posttest control .150 36 .039 .928 36 .021 a. lilliefors significance correction based on table 1. the normality of the test results above is known that the results of the experimental group posttest significance value (sig) on the posttest score of the experimental class 0.73> 0.05 while the posttest score of the control class 0.21> 0.05. this shows that the data is normally distributed because the significance is 0.21> 0.05. therefore it can be concluded that both are normally distributed. next, to find out whether or not some of the variants of the research data were tested for homogeneity. criteria for decision making 0.05. in this homogeneity test, the researchers used spss 20. the results of the homogeneity test can be seen in the following table. sri rahayu et al / geosi vol 4 no 3 (2019) 291-301 298 table 2. distribution of homogeneity test results levene statistic df1 df2 sig. spatial thinking ability based on mean .000 1 70 .983 based on median .013 1 70 .908 based on median and with adjusted df .013 1 69.59 1 .908 based on trimmed mean .005 1 70 .942 based on table 2, it is known that the results of the posttest of the experimental and control groups, obtained a significance value of 0.983> 0.05, it can be concluded that the variants of the experimental and control groups are homogeneous. after observing the characteristics of the variables that have been studied and the requirements of the analysis, then testing the hypothesis. for the purposes of the hypothesis, inferential statistics are used with the help of spss version 20, namely t-test statistics. the decision-making criteria are as follows: if sig> 0.05, ho is accepted if sig <0.05 then ho is rejected hypothesis testing, the step taken is to analyze the results of the t-test. the results of the t test analysis can be seen in table 3. table 3. experiment and control posttest t-test results mean std. deviation df thitung ttabel sig (2tailed) conclusion experimen 82,92 7.962 70 8.651 1.666 .000 h0rejected control 66,39 8.247 ardyodyantoro's research results (2014) on "utilization of google earth in geography learning to improve student learning outcomes of class x high school widya kutoarjo" shows that learning using google earth media is effective in improving learning outcomes in geography. learning outcomes with google earth media are higher than learning outcomes with lectures. the mean value of learning outcomes with google earth media 83,397, while with lectures 78,348. improved learning outcomes indicated by the achievement score of 0.68 sri rahayu et al / geosi vol 4 no 3 (2019) 291-301 299 improvements in the experimental class and 0.58 in the control class. p value of learning outcomes 0.01 <0.05, then ha is accepted and h0 is rejected. this proves that the use of google earth media in learning geography is effective in improving the learning outcomes of class x high school students widya kutoarjo. isnaini's research results (2015) on "comparative use of google earth media with digital maps on class xi ips fauna distribution materials in state high school 1 semarang" shows that (right-side t-test) shows a tcount of 2,433 and a table of 1.67 with a significance level of 5 % and dk = 31 + 31 2 = 60, because tcount> ttable, it was concluded that the experimental group taught using the google earth media the learning outcomes were better than the control group taught using digital map media. this means that the research hypothesis was accepted. meanwhile, nofirman (2018) conducted a study on the geographical spatial ability of class xii students of sma negeri 6 bengkulu city showing that the results of data processing it was found that the spatial abilities of class xii students at sman 6 bengkulu there is in the largest group (43.55%). the potential geographic spatial ability of class xii students in city 6 of bengkulu city on the group with the largest number of 38.71%. the average position is in the highest score group. furthermore, the results of ervina, asyik and mizwar (2012) research on "the influence of the use of google earth and maps media in the improvement of geography learning outcomes in material of southeast asian regional at sma negeri 14 bandar lampung in the academic year 2011/2012" shows that there are differences in the increase in results student learning and the value of student learning outcomes on the use of google earth media is higher than the use of media maps. meanwhile, the results of oktavianto, et al (2017) research on "the effect of google earth assist project based learning to spatial thinking ability" shows that google earth-aided project-based learning has a significant effect on students' spatial thinking skills. in addition, also found several advantages of google earth-based project-based learning, including: (1) encouraging students to be solve real problems through project activities, (2) students are more active in learning, (3) student performance in completing projects are more organized, (4) students have more freedom to complete projects, (5) students are motivated to compete to produce the best products, and (6) students experience increased spatial thinking skills. sri rahayu et al / geosi vol 4 no 3 (2019) 291-301 300 the use of google earth in learning geography has an effect to students on spatial thinking ability indicated by an increase in student learning outcomes after using google earth while learning. in addition, student activities and attention increase and students' difficulty in understanding spatial decreases. 4. conclusion based on the results of research, it can be concluded that there is a significant influence between the use of google earth on the spatial thinking abilities of students in class x sma pgri 2 palembang. judging from the average value of the experimental class's posttest is 82.92 and the posttest of the control class is 66.39. this has been proven by examiners that the t-count ha is accepted, that's indicating that there are differences in the spatial thinking ability of the experimental group students who are treated using google earth during the learning process. the significance of the results of the posttest t-test from the two experimental and control groups was 0.000, and then the null hypothesis ho was declared rejected because, based on the t-test criteria, the significance value was <0.05 or the sig (2-tailed) value of 0,000 was obtained <0.05. conflict of interest the authors declare that there is no conflict of interest with any financial organization regarding the material discussed in the article. references aliman, mutia, & yustesia. (2018). integrasi kebangsaan dalam tes berpikir spasial. jurnal geografi fkip ump , 82-89. arikunto, s. (2010). prosedur penelitian suatu pendekatan praktik. jakarta: rineka cipta. ardyodyantoro, gatty. (2014). pemanfaatan google earth dalam pembelajaran geografi untuk meningkatkan hasil belajar siswa kelas x sma widya kutoarjo. skripsi. program studi pendidikan geografi fakultas ilmu sosial universitas negeri yogyakarta. cuviello, matthew p. (2010). evaluating google earth in the classroom. new york : center for teaching excellence sri rahayu et al / geosi vol 4 no 3 (2019) 291-301 301 ervina, e., asyik, b., & miswar, d. (2012). pengaruh penggunaan media google earth dan peta terhadap peningkatan hasil belajar geografi. jpg (jurnal penelitian geografi), 1(1). hidayat, k. n., & fiantika, f. r. (2017). analisis proses berfikir spasial siswa pada materi geometri. prosiding si manis (seminar nasional integrasi matematika dan nilai islami) , 385-394. isnaini, n. (2018). komparasi penggunaan media google earth dengan peta digital pada materi persebaran fauna kelas xi ips di sma negeri 1 semarang. jurnal geografi: media informasi pengembangan dan profesi kegeografian, 12(1), 52-61. jo, i., & hong, j. e. (2018). geography education, spatial thinking, and geospatial technologies: introduction to the special issue. international journal of geospatial and environmental research, 5(3), 1. liu, r., greene, r., li, x., wang, t., lu, m., & xu, y. (2019). comparing geoinformation and geography students’ spatial thinking skills with a human-geography pedagogical approach in a chinese context. sustainability, 11(20), 5573. doi:10.3390/su11205573 nofirman, n. (2019). studi kemampuan spasial geografi siswa kelas xii sma negeri 6 kota bengkulu. jurnal georafflesia: artikel ilmiah pendidikan geografi, 3(2), 11-24. oktavianto, d. a. (2017). pengaruh pembelajaran berbasis proyek berbantuan google earth terhadap keterampilan berpikir spasial. jurnal teknodik, 21(1), 059. patterson, t. c. (2007). google earth as a (not just) geography education tool. journal of geography, 106(4), 145–152. doi:10.1080/00221340701678032 setiawan, i. (2016). peran sistem informasi geografis (sig) dalam meningkatkan kemampuan berpikir spasial (spatial thinking). jurnal geografi gea, 15(1). doi:10.17509/gea.v15i1.4187 sugiyono. (2010). metode penelitian pendidikan pendekatan kuantitatif, kualitatif, dan r&d. bandung: alfabeta. sudjana. (2005). metode statistika. bandung: tarsito. yousman, y. (2008). google earth. yogyakarta: c.v andi. la ode nursalam et al / geosi vol 4 no 3 (2019) 280-290 280 mapping of subsurface geological structure and land cover using microgravity techniques for geography and geophysic surveys: a case study of maluri park, malaysia la ode nursalam1, a arisona2, ramli1, la harudu1, eko harianto3, sitti kasmiati4, fahrudi ahwan ikhsan5, andri estining sejati6 1department of geography education, halu oleo university, kendari, sulawesi tenggara, 93232, indonesia 2department of geology engineering, halu oleo university, kendari, sulawesi tenggara, 93232, indonesia 3department of agrobusiness, kendari terbuka university, kendari, sulawesi tenggara, 93232, indonesia 4department of archeology, halu oleo university, kendari, sulawesi tenggara 93232, indonesia 5department of geography education, jember university, east java, 68121, indonesia 6department of geography education, sembilanbelas november kolaka university, kolaka, sulawesi tenggara 93561, indonesia email: laodenursalam77@gmail.com received 13 september 2019/ revised 9 november 2019/ accepted 22 november 2019/ published 1 december 2019/ available online 25 november 2019 abstract a microgravity investigation on bedrock topography was conducted at maluri park reference level in kuala lumpur, malaysia. the study aim to mapping the near-surface structure and soil and land cover distribution for geography and geophysics surveys. two types of crosssection modeling of the residual anomaly generated the maluribouguer anomaly model for site-1 and site-2 at maluri park. the 2d microgravity models produced the contour map, displaying the characterization due to density contrast in rock types while mapping the subsurface geological structure at different depths. moreover, a synthetic model was initiated with the assumption of lateral distance on the left and right sides taken at 50 m and a depth of 60 m. the results of modeling confirmed that the soil and rock type composition on both models site tests are topsoil (1.1 to 1.92 g/cm3), soil (1.8 g/cm3), clay (1.63 g/cm3), gravel (1.7 g/cm3), sand (2.0 g/cm3), shale (2.4 g/cm3), sandstone (2.76 g/cm3), and limestone (2.9 g/cm3). the 2d gravity modeling using two model site tests obtained a correspondence with the observed microgravity data. keywords: bouguer anomaly, limestone, microgravity, soil structure, topography. 1. introduction the survey area is underlain by limestones. the survey area in maluri park in eastern kuala lumpur, malaysia, near cheras. the survey location can be seen in the fig.1. it is commonly understood that limestones pose a certain threat to soil structures. as limestones are generally easily dissolved by water, voids and cavities are common internal structures of this type of rock (arisona et al., 2018). identification of such structures can help to ensure sustainability, especially for land cover and strategic structures. the area under study is geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.4 no. 3 (2019), 280-290, december, 2019 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v4i3.13738 accredited by the ministry of research, technology and higher education of the republic of indonesia, no. 30/e/kpt/2019 la ode nursalam et al / geosi vol 4 no 3 (2019) 280-290 281 planned for both establishment of transportation facilities and an economic and urbanization projects. the motivation of the present work is to help reducing the threats to soil structures in the mentioned projects. a significant application of geography and geophysical methods in mapping practice is to determine the bedrock and the characteristics of soil structure (grandjean, 2009; hiltunen, 2012). the gravity method is widely used for geography and geophysical surveys, especially in the detection of subsurface geological features and land covers. gravity' anomalities controlled by the lateral variation of densities or other words, the lateral density contrast. generally speaking, modeling of gravity data in 2d sections is useful for the determination of the depth of various features and can be done by either forward or inverse algorithms. in similarity with other geography and geophysical methods, the interpretation of gravity data is non-unique because many possible models could result in the same gravity anomaly. constraints from borehole data can help to reduce the uncertainties greatly. the kind of useful information for this purpose in the depths of rock boundaries and rock densities. the irregular structure of limestones and land cover produces gravity anomalies, which are our target for gravity analysis and modeling. in other words, gravity anomalies are modeled to determine the subsurface structure and land cover problems. figure1. survey location: maluri park, malaysia la ode nursalam et al / geosi vol 4 no 3 (2019) 280-290 282 as mentioned, the problem targeted by the present work is the presence of voids or cavities underneath the sites under the survey area. these cavities are either empty (i.e. filled with air or water) or filled with loose sediments. in both cases, the lateral density contrast is large, which favors the application of microgravity techniques. as the density of the cavities or voids is low compared to the surrounding host limestone bed, the anomalies will be negative. hence, the analysis focusses on these negative anomalies for modeling their dimension and depth(zabidi et al., 2011). in this study, we perform microgravity modeling using physical parameters from real data that are robust. the bedrock within the survey area is a limestone formation. limestone formations are well known for their highly unusual karstic features (tan, 2005). as a consequence, the depth of the limestone bedrock is highly irregular. the overburden soils above limestone formation are mainly silty sands with significantly variable thickness due to the irregular topography of the limestone bedrock (zabidi et al., 2011). the soil thickness in the survey is that trends show variations of overburden soil between 3 m and 5 m. the soil is comprised mainly of sandy silt with embedded layers of soft clay. moreover, the residual soil above the limestone bedrock is mainly loose fine-grained materials. the soil color in the survey area is light greyish-brown and mostly sandy. they are described and named according to the grain size classification as silty clay, clayey silt, silty sand, and sandy clay. some are identified as fill and slime materials. they are essentially loose and soft material and are probably transported materials (yusoff et al., 2016). the purpose of the research is mapping the near-surface structure and soil and land cover distribution for geography and geophysical surveys. 2. methods microgravity data from the survey area were processed using surfer ® 13 software , which reduced bouguer anomaly values at each station of the microgravity survey. fig.2 shows that the modeling has been well constrained because the parameters required to obtained the bedrock topography were well defined from the borehole data (figure 3). according to samsuddin (2003), modeling enables the determination of the presence of ridge and valley features. additionally, the modeling indicates that there can be smaller features such as cracks or steep, narrow valleys within the ridges. this result explains the differences in the limestone depth in nearby boreholes. the post-processing procedure checked the microgravity instrument corrections for latitude and longitude, diurnal variations, and instrument drift using base station polynomial drift values and relative elevation. this procedure is merged with the respective gravity station la ode nursalam et al / geosi vol 4 no 3 (2019) 280-290 283 topographic survey data, which is being modeled. the same density value of 1.8 g∕cm3 was used to calculate the bouguer correction for all survey data sets. table 1 presents the density of rock types that were reviewed in this study. table 1. rock types density values rock type density range (gr/cm3) average (gr/cm3) source sediment rock overburden (topsoil) 1.92 soil 1.20 to 2.40 1.92 clay 1.63 to 2.60 2.21 gravel 1.70 to 2.40 2.00 sand 1.70 to 2.30 2.00 telford et al.,1990 sandstone 1.61 to 2.76 2.35 shale 1.77 to 3.20 2.40 limestone 1.93 to 2.90 2.55 dolomite 2.28 to 2.90 2.70 subsequent processing was the elevation correction to address the variation in data points due to the topography. this evaluation is necessary for the 2d geotechnical modeling (pringle,2012). furthermore, the removal of regional values (low frequency and high amplitude) to express the residual anomalies (high frequency and low amplitude) was performed. the modeling of the residual anomaly was generated in cooper ™ grav2dc v.2.10 software. however, qualitative interpretation using geological and geography maps are used only as additional information. according to (amaluddin et al., 2019) geological formation or structure for instance can use the maps which poured in the data field or 2d. the qualitative interpretation explains the anomaly by geological and geophysical information. on this basis, the geological structure and distribution of masses of different densities may be delineated. the gravity anomaly in the study area might be generated in the field due to the following factors; variations in the thickness, density differences of the subcrustal matter (crustal thickness), density variation within the basement rocks, thickness variations of the sedimentary rocks, and density variations within the sedimentary rocks. the difference in density values can be correlated to divergent material types such as soil, rock, and voids (samsuddin,2003). la ode nursalam et al / geosi vol 4 no 3 (2019) 280-290 284 figure 2.a 2d microgravity contour map at maluri station compiled from topography and bouguer anomalies at site test-1 and site test-2. the microgravity countur color information above is on the right and adjusted the rock conditions in the study site. figure 3. borehole (bh) logs showing bedrock rl at maluri station la ode nursalam et al / geosi vol 4 no 3 (2019) 280-290 285 3. results and discussion the bedrock topography for the maluri station was compiled from bh results, secant bored piles (sbp) and kingpost, and the gravity model. the density values were not uniform, which showed that some lines in the study area lack good control. the bedrock topography map is shown in fig. 4was correlated with the 31boreholes, where the average topography height of about 39.91mwas determined (figure 3). two sinkholes were detected in the study area in the southeast of the survey area. the sinkholes occurred near the lrt bridge, which might occur under the devotional of clay construction site tests. the cause of the sinkhole is attributed to the dissolution of the limestone bedrock and the subsequent raveling of the overburden soil cover. figure 4.maluri station bedrock topography model. la ode nursalam et al / geosi vol 4 no 3 (2019) 280-290 286 the gravity pattern correlates subsurface topography of bedrock (tajuddin and lat, 2004). the results of this investigation confirmed earlier borehole results which indicated thepresence of the cavities (samsudin, 2003). however, the uneven distribution and clustering of the data necessitate the use of an interpolation algorithm to create a uniformly spaced grid. all data processing in the contour map was generated with cooper ™ surfer ®13software. the survey results were represented in contour maps for delineating anomalies varying from negative to a positive value. according to kamal et al. (2010), negative values are interpreted as low density subsurface layers and for the possibility of the existence of cavities. no density measurements were made during this work. the density values used are based on the investigations of soils and foundations sdn. bhd., employing a superficial deposit density of1.8 g/cm3. table 1presents the density of rock types that were reviewed in this study. fig 5 shows the results of the microgravity data of maluri site for the bouguer, regional, and residual anomalies. fig. 5a displays the tendency of response towards positive anomalies, and yet it was not significant to influence the gravity anomaly around model site test-1. the small variation in gravity responses may be due to the effect of the distribution of rainwater around the area and the inhomogeneity in the soil types. fig.5b shows the gravity anomaly at model site test-2, characterized by negative values, probably due to the inhomogeneous geo-materials consisting of a mixture of clay and silt with grain sizes, which is from fine to medium. additional geological and geography mapping showed that the complexity of the subsurface profile regarding the geomaterials, geological structure, and water seepage influences the contrast in the zones, thus resulting in some of the inconsistency of the gravity values. figure 5. results of gravity field measurements at maluri site for (a) profiles site test-1 and (b) profiles site test-2 using extracted techniques from anomaly contour maps. la ode nursalam et al / geosi vol 4 no 3 (2019) 280-290 287 figs. 5a and 5b show results of the 2d geotechnical model generated with cooper ™ grav2dc v.2.10 software. the two curves for the model at the sites confirmed the product of a misfit of4.44 % and 3.18 %between calculated curves with observed curves. furthermore, modelcalculated gravity confirmed density contrast at both model sites as shown in table 2. table 2. estimated density contrast from gravity field measurements at maluri site for (a) profiles site test-1 and (b) profiles site test-2 model site test-1 model site test-2 density (g/cm3) rock type density (g/cm3) rock type 1.80 soil 1.10 dry density 1.63 clay 1.80 clayey, sandy silt 2.00 gravel 1.20 clay 1.70 sand 1.92 overburden (topsoil) 2.40 shale 2.76 sandstone 2.90 limestone rms error = 4.44 % rms error = 3.18 % fig. 5 shows the zones associated with negative anomalies. an important to observation is the decrease of soil compactness due to the cavity and existence of groundwater around the area. in other words, the model site test encountered a unsewed soil at an adepth of about 5 to 10 m filled with water. additionally, different factors include changes in gravity values caused by the dynamics around the observation points, such as variations in the depth of the groundwater level and land subsidence. the occurrence of strain and shear failure due to loading at the top layer of soil could be another reason. in general, loading in the ground layers produces strain in the sediments (fig.5), a decline in groundwater level at a depth of 15 m to 35 m). strain observed in this area could be due to variation in the composition of the soil and water in the cavities. the loading effect is often referred to as consolidation. as a result, regional anomalies when compared with bouguer anomalies in a horizontal plane, the obtained residual anomalies are still significant. this difference is probably caused by the material homogeneity and similarity of the geological structure. the residual anomaly values are not affected by topography. anomalies appear in the northeast and northwest. that result in line with the research (arisona et al, 2018), difference assumed that this contrast is affected by density variations of the host rock and the possibility of rock density. the difference location implies that the anomaly is a result of different depth to the bedrock, different thickness of the overlying material la ode nursalam et al / geosi vol 4 no 3 (2019) 280-290 288 the bouguer anomaly map result characterized the density contrast due to rock type and mapped subsurface geological structure and land cover at different depth. the research (samsuddin, 2003) describes that the modeling enables the determination of the presence of ridge and valley features. additionally, the modeling indicates that there can be smaller features such as cracks or steep, narrow valleys within the ridges. the result is eight rock types from the profiling from different and depth. it is shown that the mapping for a geophysics survey can obtain information matching with the mapping aim. the research (wanjohi, 2014) geophysical field mapping is the process in selecting the interest area, then identifying all geophysical aspect matching with the mapping aim. the mapping aim in the research (wanjohi, 2014) is to understand all physical parameters of a geothermal field. the survey results were represented in contour maps for delineating anomalies varying from negative to a positive value. mapping in a geophysical method in the research (georgsson, 2009) uses contouring to see the object interest phenomena. the contour or line data combined with other data like a polygon in the form of coloring. microgravity method solves problems targeted by the present work is the presence of voids or cavities underneath the sites under the survey area. according to the previous research (tuckwell, grossey, owen, & stearns, 2008) that micrografity establihed as technique for detection natural or man-made cavilities. in the case mounchel parkman on behalf of herfordshire country council, a doline had opened up within a school playground. that example in the natural voids in the limestone bedrock. 4. conclusion the result obtained from the grav2dc v.2.10 software correlates the model-calculated gravity, and the corrected gravity data in site tests have minimal percentage errors. the results of modeling showed that there are eight rock types from the gravity profiles; topsoil (1.1 to 1.92 g/cm3), soil (1.8 g/cm3), clay (1.63 g/cm3), gravel (1.7 g/cm3), sand (2.0 g/cm3), shale (2.4 g/cm3), sandstone (2.76 g/cm3) and limestone (2.9 g/cm3). the utilization of extracted technique characterized the density contrast due to rock type and mapped subsurface geological structure and land cover for geography at different and depth. models of microgravity distribution in the ground could be useful for the mapping of variations in soil composition. the changes in gravity anomaly observed throughout the sections were due to the heterogeneities in the composition of the subsurface materials and density contrasts in the study area. the information on the background lithology is paramount for an acceptable interpretation in a microgravity modeling of soil structure. la ode nursalam et al / geosi vol 4 no 3 (2019) 280-290 289 conflict of interest the authors declare that there is no conflict of interest with any financial organization regarding the material discussed in the article. acknowledgment this study is a collaboration with a graduate student of the physics and geography education study program, at halu oleo university. we thank to a colleague at halu oleo university, which has been giving us for their guidance, comment, and correction on this paper. references amaluddin, l. o., rahmat, r., surdin, s., ramadhan, m. i., hidayat, d. n., purwana, i. g., & fayanto, s. (2019). the effectiveness of outdoor learning in improving spatial intelligence. journal for the education of gifted young scientists, 7(3), 667–680. https://doi.org/10.17478/jegys.613987 arisona,a., mohd n., amin e.k., &abdullahi, a.(2018).assessment of microgravity anomalies of soil structure for geotechnical 2d models.journal of geoscience, engineering, environment, and technology (jgeet)3(3), 151-154. georgsson, l.s. (2009). geophysical methotds used in geothermal exploration. presented at exploration for geothermal resources, 1-22 november 2009, 1-16. grandjean, g. (2009). from geophysical parameters to soil characteristics.florida: report n°brgm/fp7-digisoil project deliverable 2.1, final reportdepartment of civil and coastal engineeringuniversity of florida. hiltunen, d.r., hudyma,n.,tran,k.t.,&sarno,a.i. (2012).geophysical testing of rock and its relationthipsto physical properties.florida:final reportdepartment ofcivil and coastal engineeringuniversity offlorida. kirsch,r. (2006).groundwatergeophysics, atool for hydrogeology.new york: springer. kamal,h.,taha,m.,&al-sanad,s. (2010). geoenvironmental engineering and geotechnics, geoshanghai 2010 international conference. (accessed 02.03.17) lilie, r.j. (1999).whole earth geophysics: an introductory textbook for geologists and geophysicists. new jersey:prentice-hallinc. pringle, j.k., styles, p., howell, c.p.,branston, m.w., furner, r., &toon,s.m. (2012). longterm time-lapse microgravity and geotechnical monitoring of relict salt mines, marston, cheshire, uk. geophysic77(6), 165-171. samsudin, h.t.(2003).a microgravity survey over deep limestone bedrock.bulletin of geological society of malaysia4(6), 201-208. la ode nursalam et al / geosi vol 4 no 3 (2019) 280-290 290 tan, s.m. (2005). karsticfeatures of kualalumpur limestone. bulletin of the institution of enginnermalaysia 4(7), 6-11. tajuddin, a.&lat, c.n. (2004).detecting subsurfacevoids using the microgravity method, a case study from kualalipis, pahang.bulletin of geological society of malaysia 3(48), 31-35. tuckwell, g., grossey, t., owen, s., & stearns, p. (2008). the use of microgravity to detect small distributed voids and low-density ground. quarterly journal of engineering geology and hydrogeology, 41(3), 371–380. https://doi.org/10.1144/1470-9236/07-224 wanjohi, a.w. (2014). geophysical field mapping. presented at exploration for geothermal resources, 2-23 november 2014, 1-9. yusoff , z.m., raju,g. &nahazanan, h.(2016).static and dynamic behaviour of kualalumpur limestone. malaysian journal of civil engineering special issue vol.28 (1), p.:18-25. zabidi, h. & de freitas, m.h. (2011).re-evaluation of rock core logging for the prediction of preferred orientations of karst in the kualalumpur limestone formation. engineering geology, 117(3-4), p.: 159–169. 196 ripon hore et al / geosi vol 5 no 2 (2020) 196-209 soil zonation and the shaking table test of the embankment on clayey soil ripon hore1*, sudipta chakraborty2, md. fayjul bari1, ayaz mahmud shuvon2, and mehedi ahmed ansary1 1department of civil engineering, bangladesh university of engineering and technology (buet), dhaka, 1000, bangladesh 2bangladesh network office for urban safety (bnus), bangladesh university of engineering and technology, dhaka, 1000, bangladesh *corresponding author : riponhore@gmail.com received 22 march 2020/ revised 5 june 2020 / accepted 21 june 2020/ available online 28 june 2020 abstract the main objective of this research was to model the zonation of wrap faced embankment on soft clay foundation, by applying a shake table test. also, to investigate the dynamic behaviors of clay soil, such as acceleration amplification, displacement and pore water pressure of wrap faced embankment. this was done with respect to changes in frequencies of 1 hz, 3 hz, 5 hz, 10 hz, 12 hz and 15 hz respectively. constant acceleration (0.1 g) and surcharge (19 kg) were applied by using a laminar box, placed on a shake table testing machine. the main elements of this research were the laboratory test, which was used for preparing reconstitute soil samples, and wrap faced embankment with frequency arrangement. after applying all test parameters, dynamic parameters were increased by rise in elevation with respect to frequency. the result shows that the maximum dynamic parameters were found at the frequency of 10 hz. it is beneficial to the relative performances of the wrap faced embankment, which is the updated design parameter. keywords: seismic; clay soil; frequency; shake table test; wrap faced; soil zonation 1. introduction the soil-foundation formed from soft clay becomes the focus of seismic engineering. in some cases, the foundation on soft clay is creating a problem for the design and construction of any type of structure. in bangladesh, the southern part of the country, an geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.5 no. 2 (2020), 196-209, august, 2020 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v5i2.17873 accredited by the ministry of research , technology , and higher education of the republic of indonesia, no. 30/e/kpt/2019. https://jurnal.unej.ac.id/index.php/geosi https://drive.google.com/file/d/1rsnvas6cuhowhl5bj87cl2l6k5dqz7s6/view 197 ripon hore et al / geosi vol 5 no 2 (2020) 196-209 excessive amount of soft clay is found in the khulna and bagerhat districts and also in the surroundings of dhaka city (hore et al., 2019). bangladesh has the largest delta in the world. therefore, very large alluviums are deposited on its surface. the oldest deposits are the barend, madhapur and lamaicregion clay. the sediments deposited are not evenly distributed throughout the country. at the northern part, it is about 128 m thick and this is where granite is extracted for construction purposes. conversely, the thickness was gradually increased towards the south. at the centre, the capital city, dhaka of bangladesh has a sediment covering of over 22 km (al zaman & jahan monira, 2017; alam & islam, 2009; bazlar rashid et al., 2018; haque et al., 2013; hore et al., 2019). earthquakes or any seismic effects may cause a major damage on this type of soil. the earthquakes or any sinusoidal waves (railway vibration) have often created significant problems during the design and construction of the embankment. moreover, it may be damaged due to the softening of soilfoundation (ering & sivakumar babu, 2020; krishna & latha, 2007; kumar et al., 2020; latha & krishna, 2006; zhou et al., 2020). the soil and structure interaction (ssi) system was considered in this experimental study, to simulate actual soil-foundation (bullock et al., 2019; çelebi et al., 2019; he & jiang, 2019; hore et al., 2020; srilatha, et al., 2013; srinivasan et al., 2016). soft soils in dhaka, bangladesh were used to build the soilfoundation. krishna & latha (2007) determined the result of shake table tests on geotextilereinforced wrap faced soil-retaining walls. a total number of 9 model tests were described, such as development, experiment methodology, and outcomes. srilatha et al., (2013) illustrated the effect of frequency of base shakes on the dynamic response of unreinforced and reinforced soil slopes. xiao et al., (2014) investigated the earthquake response of a slurry wall and presented a minimized scale shake table test. in this research, soil-cement-bentonite (scb) was evaluated. this is also a common type of slurry wall. reinforced soil is only slightly damaged during the recent seismic disasters in japan (suzuki et al., 2015). the seismic behaviour of this soil wall is formed from clay, cement-treated clay, sand based on shake table tests and results of the pull-out. fleming et al., (2016) conducted a contemporary phenomenon on soft clay soil, to determine the consequences of soil improvement on the seismic resistance of piles. yazdandoust (2017) conducted a recent laboratory test to assess the character of 1-g shake table tests. many researchers also performed a shake table test to study the seismic responses of different soil structures on soft soil (beskhyroun et al., 2011; 198 ripon hore et al / geosi vol 5 no 2 (2020) 196-209 edinçliler & toksoy, 2017; hamayoon et al., 2016; hassan & pal, 2018; helwany et al., 2017; madhavi latha & manju, 2016). few researchers focused on shake table tests on soft clay soil in south asian regions. in bangladesh, there have been limited studies related to shake table tests of wrap faced retaining walls, on soft clay. therefore, the purpose of this research was to study the effects of frequency on reinforced soil wall models. the objectives of this study were to: a) measure the response of wrap faced and reinforced soil retaining wall, which was subjected to dynamic loading through shake table; b) investigate the acceleration amplification, deformation, and pore water pressure with respect to frequency response; c) to zone the wrap faced embankment on the soft clay foundation, by applying a shake table test, and d) draw the contour maps using plaxis 3d software. 2. methods 2.1 area of study the clay soil sample was collected at a depth of 1.5 m below the existing ground level from the dhaka city of bangladesh as shown in figure 1. these homogeneous, stiff, reddish brown samples were at first oven-dried. subsequently, the dry lumps were then powdered gently by using a wooden hammer. it was finally sieved through a 200 standard sieve to obtain clean clay-like soil powder. this type of clay is very dominant in catchment areas (areas around ariver) with a thickness from 1 to 20 m. a total number of 1000 drill holes were carried out for the standard penetration test (spt) in and around bangladesh. furthermore, 470 drill holes were chosen for the formation of soft clay layers. in addition, a map identified with zoning for spt values were from 1 to 5. the total area was divided into five subsections according to the thickness of soft clay soil. the lower range of soft clay thickness is 0 to 1 and the higher range is between 10 to 20. from the thickness map and bore log, spt n zone was realized. the target of this study was to obtain the accuracy of the seismic design of roadway and rail sub structure, based on the aforementioned necessities. on this model embankment, 100 shake table tests were experimented. the analysis implemented a repeated loading and unloading process. 199 ripon hore et al / geosi vol 5 no 2 (2020) 196-209 figure 1. study area and the thickness map for soft soil in bangladesh 2.2 using equipment and materials the shake table facility, which is computer-controlled, was used to simulate the horizontal shake action associated with dynamics. the platform of testing was a square, with a dimension of 2.5×2.5 m² and an approximate payload capacity of 1100 kg, made up of steel plates. the range of acceleration is 0.05 g to 2 g. the frequency range is 0.05 to 50 hz with a maximum amplitude of ±200 mm. the highest velocity is 0.03 m/s. the shake table test machine is shown in figure 2. the laminar box is positioned on the shake table as presented in figure 3. figure 2. shake table test apparatus figure 3. laminar box mounted on shake table a laminar box was constructed on the shake table apparatus to reduce boundary effects wherever possible. the laminar box neither resists nor promotes soil displacement to 200 ripon hore et al / geosi vol 5 no 2 (2020) 196-209 accommodate the movement of soil. the laminar shear box has 24 hollow aluminum layers of frames developed at bangladesh university of engineering and technology (buet). every layer consists of an internal structure with internal dimensions of 915 mm × 1220 mm × 1220 mm. a laminar box was constructed on the shake table apparatus to reduce boundary effects wherever possible. the laminar box neither resists nor promotes soil displacement to accommodate the movement of soil. the laminar shear box has 24 hollow aluminum layers of frames developed at buet. every layer consists of an internal structure with internal dimensions of 915 mm × 1220 mm × 1220 mm. sylhet sand was used as the backfill material that was available locally. the unified soil classification system classified the sand as poorly graded sand (s.p). the maximum and minimum dry densities were 18 kn/m³ and 16 kn/m³m3, respectively. the specific gravity of the sand particles was 2.34. the relative density of sand was 60%. the soft clay soil in dhaka was used in this research work.the liquid limit and water content of this soil sample were found at 40% and 23% respectively. the soil sample used was prepared, by using 50% of water content (1.25 times of liquid limit). cohesion was obtained by 14.8 kn/m² and friction was obtained by 1.0 from the direct shear test. the water content of the soil sample was 14%, and the unconfined compressive strength (qu) was 19 kpa, after the loading had been done. the thickness of the clay layer in the soil sample was 6 m. reconstituted soil sample preparation was displayed in figure 4. figure 5 illustrates the schematic diagram of the test configuration. figure 4. preparation of clay layer figure 5. schematic illustration of shake table test 2.3 testing procedure the dimension of the laminar box was 1220 mm deep, and the size of the plan area was 915 mm × 1220 mm. in lifts of equal height, the model was constructed while 201 ripon hore et al / geosi vol 5 no 2 (2020) 196-209 reinforcing each lift with a layer of woven geotextile. to measure pore water pressure, two pore water sensors (p1 and p2) were placed as shown in figure 5. besides this, 6 acceleration sensors (a1, a2, a3, a4, a5, and a6) were placed on different points of the model, to measure acceleration. a1 and a2 sensors were placed in clay soil layers. three displacement sensors (lvdt1, lvdt2, and lvdt3), were placed on different locations of the model to measure the displacement of the embankment. table 1 shows the test sequence. table 1. test sequence test name acceleration amax(g) frequency hz relative density (%) surcharge (kg) ft1 0.1 1 60 19 ft2 0.1 3 60 19 ft3 0.1 5 60 19 ft4 0.1 10 60 19 ft5 0.1 12 60 19 ft6 0.1 15 60 19 3. results and discussion the total number of 100 shaking table tests were conducted for this research. in this section, 6 shake table tests were described among the 100 shaking tests to evaluate the seismic response of the model retaining wall. the chosen base accelerations for this research were 0.1 g, 0.2 g, 0.3 g, 0.4 g, and 0.5 g respectively. the natural frequency in this shake table test was determined to be 16 hz. therefore, input frequency should be less than the natural frequency of the model. the input frequencies were 1 hz, 3 hz, 5 hz, 10 hz, 12 hz and 15 hz respectively. the surcharge pressures selected for this study were 19 kg, 34 kg, and 49 kg. a total number of 470 layers of soft clay soil were also presented in the gis interface map. the standard penetration test (spt) zonation map was prepared based on spt n value. the spt zone map has four sub sections. the lower range of spt zonation map is 1 to 2 and the higher range is greater than 5. the n value is less than five, showing the existence of soft clay content of that area. this influences the dynamic behaviours of the embankment, (hore et al., 2019). from the map (figure 6), the green colour shows the spt value between 1 to 2. the capital of bangladesh, dhaka, is occupied with soft clay zone containing spt value 1 to 2. the output result was the dynamic behaviour like acceleration amplification, displacement and pore water pressure. this was shown in the contour map and the graph. the research 202 ripon hore et al / geosi vol 5 no 2 (2020) 196-209 showed that dynamic behaviour of the soil depends on the soil standard penetration test result. the zonation map using standard penetration test (n) value was shown in figure 6. figure 6. zonation map using standard penetration test (spt) 3.1 acceleration response the dynamic parameters for acceleration amplification response were ft1, ft2, ft 3, ft4, ft5, ft6 with frequencies of 1 hz , 3 hz , 5 hz , 10 hz , 12 hz and 15 hz respectively. these were conducted at 0.1 g base acceleration and 19 kg surcharge pressure, as shown in figure 7. figure 8 shows the acceleration amplification variation with respect to frequency without clay layers. figure 7 displays the two sensors in the clay soil sample layer for the different frequencies of 1 hz, 3 hz, 5 hz, 10 hz, 12 hz and 15 hz from ft1, ft2, ft3, ft4, ft5, and ft6 model tests respectively. from the figure, it can be seen that acceleration amplitude decreases, with increasing normalized elevation,for the frequency of 1 hz. conversely, acceleration amplitude increases with rise innormalized elevation for other frequencies. the previous figure shows that acceleration amplification and frequency are not directly proportional. in fact, within the range of tests conducted, accelerations were amplified less for 1 hz, 3 hz, and 5 hz and more for 10 hz and 12 hz compared to that of 15 hz at all elevations. moreover, accelerations at normalized elevations of 0.25, 0.5, 075, and 1 203 ripon hore et al / geosi vol 5 no 2 (2020) 196-209 were amplified closer or slightly more than 1 for the frequency of 1 hz. the differences in acceleration amplification for various frequencies were increased with increase in wall height. at a normalized height of 1, for 1 hz, 3 hz, 5 hz, 10 hz, 12 hz, and 15 hz, the values for acceleration amplification were 1.04, 1.24, 1.46, 3.26, 2.47, and 1.80 respectively. these test results of acceleration are partially similar to the (cai et al., 2019; fleming et al., 2016; hore et al., 2020). 3.2 face displacement response figure 9 shows the displacement profiles observed for tests ft1, ft2, ft3, ft4, ft5, and ft6 with frequencies 1 hz, 3 hz, 5 hz, 10 hz, 12 hz and 15 hz respectively. it was observed that at the highest elevation (z/h=0.875), the displacement was maximum. the highest normalized displacement of 2.01% was observed for 12 hz frequency. the corresponding values for the frequencies of magnitudes 1 hz, 3 hz, 5 hz, 10 hz and 15 hz were 0.02 %, 1.99 %, 2.05 %, 2.01 % and 1.93 % respectively. these test results of face displacement response are partially similar to the (krishna & latha, 2007; srinivasan et al., 2016; suzuki et al., 2015). figure 7. acceleration amplification (clay layer) response on frequency figure 8. acceleration amplification response on effect of frequency frequ whole.grf acceleration amplification n o rm a li se d e le v a ti o n , z/ h 0 0.5 1 1.5 2 2.5 3 3.5 0 0.2 0.4 0.6 0.8 1 test no. freq. ft1 1hz ft2 3hz ft3 5hz ft4 10hz ft5 12hz ft6 15hz frequu.grf acceleration amplification n or rm al is ed e le va ti on , z /h 0 0.5 1 1.5 2 2.5 3 3.5 0 0.2 0.4 0.6 0.8 1 test no. freq. ft1 1hz ft2 3hz ft3 5hz ft4 10hz ft5 12hz ft6 15hz 204 ripon hore et al / geosi vol 5 no 2 (2020) 196-209 3.3 variations of pore water pressure figure 10 shows the effect of frequency for fixed base acceleration (0.1 g) and surcharge (19 kg) on acceleration amplification, strain and pore water pressures. the variations were for tests ft1, ft2, ft3, ft4, ft5 and ft6 with the frequency of 1 hz, 3 hz, 5 hz, 10 hz, 12 hz and 15 hz respectively for 0.1 g base accelerations and 19 kg surcharge. the pore water pressures increase with increasing elevation. the pore water pressure was 0.07 kpa at frequency of 10 hz. the maximum pore water pressure for model tests ft1, ft2, ft3, ft4, ft5, and ft6 were 0.02 kpa, 0.03 kpa, 0.03 kpa, 0.11 kpa, 0.09 kpa, and 0.07 kpa respectively. figure 11 shows the contour map (plaxis 3d output results) of acceleration, displacement, and pore water pressure response. figure 9. displacement profile response on frequency figure 10. pore water pressure variations 0.1g_19kg new.grf normalised face displacement, h/h (%) n o r m a li s e d e le v a t io n , z /h 1.7 1.75 1.8 1.85 1.9 1.95 2 2.05 2.1 2.15 0.3 0.36 0.42 0.48 0.54 0.6 0.66 0.72 0.78 0.84 0.9 test no. freq. ft1 1 hz ft2 3 hz ft3 5 hz ft4 10 hz ft5 12 hz ft6 15 hz 0.1g_19 kg.grf pore water pressure, kpa n o r m a li s e d e le v a t io n , z /h 0 0.025 0.05 0.075 0.1 0.125 0.15 0.175 0.2 0.225 0.25 0 0.08 0.16 0.24 0.32 0.4 0.48 0.56 0.64 0.72 0.8 test no. freq. ft1 1 hz ft2 3 hz ft3 5 hz ft4 10 hz ft5 12 hz ft6 15 hz 205 ripon hore et al / geosi vol 5 no 2 (2020) 196-209 figure 11. contour map of acceleration response figure 12. contour map of displacement response figure 13. contour map of pore water pressure response this research discusses the results found from 6 different shake table tests from 100 combinations, on the embankment with soft clay models. the acceleration of thistest varied from time to time. the acceleration of the test were as follows: 0.1 g, 0.2 g, 0.3 g, 0.4 g and 0.5 g. during the shake table test, the natural frequency was the first calculated and its test result was 16 hz. therefore, the other frequencies should be less than the natural frequency. the other frequencies were 1 hz, 3 hz, 5 hz, 10 hz, 12 hz and 15 hz. this means that the 206 ripon hore et al / geosi vol 5 no 2 (2020) 196-209 frequencies ranged from 1 hz to 15 hz. during the shake table test, surcharge pressure varied for each test. changing the surcharge pressure and wrap faced embankment was newly created. the surcharge pressures were 19 kg, 34 kg and 49 kg. after conducting the unconfined compressive test, the result was 20 kpa. the wrap faced embankment height was 4 m and therefore, the model was developed. the length (l) of the geotextile reinforcement was 3.75 m. also, 20 cycles of sinusoidal shakes were subjected to the model wall. all of the present model walls were later constructed with sand placed on the same medium to loosen density. the sand embankment properties were as follows: i) average unit weight ii) the relative density which were 18 kn/m3 and 60% respectively. these results obtained were similar to that of other researcher swho only used sand embankment without clay soil (eric et al., 2013; goktepe et al., 2019; srilatha et al., 2013). the cyclic behaviour of the soft clay has been analysed based on the different input frequency. the face deformations were high for low-frequency shaking, low for surcharge pressures and high for base accelerations. the pore water pressures were observed to increase with a rise in base motion frequency. three contour maps were drawn to investigate the acceleration amplification, deformation, and pore water pressure with respect to frequency response. these maps also showed dynamic parameters such as acceleration amplification, deformation, and pore water pressure representations of the soft soil. these results were very important for observing the dynamic behaviour of wrap faced soil retaining walls on the soft clay layer. this can be applied to improve incorporating dynamic loading, considering the design specification of this type of retaining wall (railway and road embankment). 4. conclusion the shake table test on wrap faced embankment on the clay soil foundation, is a new form of test. the lower range of spt zonation map is 1 to 2 and the maximum range is greater than 5. in bangladesh, embankment on soft clay soil plays a very vital role in seismic perspective. therefore, the research opportunity of this area will bring about an upgrade to seismic design specifications. from the test results, it was discovered that face deformation increases with rise in elevation. at high elevations and frequencies, pore water pressure is also high. these test results are beneficial in understanding the relative performance of the wrap faced embankment, which is the indicative direction to the design process of embankment. 207 ripon hore et al / geosi vol 5 no 2 (2020) 196-209 conflict of interest the authors declare that there is no conflict of interest with any financial, personal, or other relationships with other people or organizations related to the material discussed in the article. references al zaman, m. a., & jahan monira, n. (2017). a study of earthquakes in bangladesh and the data analysis of the earthquakes that were generated in bangladesh and its’ very clo se regions for the last forty years (1976-2016). journal of geology & geophysics, 06(04), 6–10. https://doi.org/10.4172/2381-8719.1000300. alam, m. j., & islam, m. s. (2009). geological aspects of soil formation of bangladesh. conference: bangladesh geotechnical conference 2009 (bgc-2009), dhaka, bongladesh. bazlar rashid, m., rashid, b., & islam, b. (2018). structure and lineaments of the northwestern part of bangladesh and evolution of the barind tract. american journal of earth sciences, 5(3), 26–36. beskhyroun, s., wegner, l. d., & sparling, b. f. (2011). integral resonant control scheme for cancelling human-induced vibrations in light-weight pedestrian structures. structural control and health monitoring, may 2011, n/a-n/a. https://doi.org/10.1002/stc. bullock, z., dashti, s., liel, a., porter, k., & karimi, z. (2019). this preprint is a pdf of a manuscript that has been accepted for. earthquake spectra (preprint), 1–33. https://doi.org/10.1016/j.ssresearch.2016.09.015. cai, w., yu, b., & kaewunruen, s. (2019). shaking table tests of suspended structures equipped with viscous dampers. applied sciences (switzerland), 9(13). https://doi.org/10.3390/app9132616. çelebi, e., göktepe, f., & omid, a. j. (2019). seismic soil response of scaled geotechnical test model on small shaking table. arabian journal of geosciences, 12(2). https://doi.org/10.1007/s12517-018-4197-8. edinçliler, a., & toksoy, y. s. (2017). shake table tests to measure the dynamic performance of geotextile-reinforced embankment. periodica polytechnica civil engineering, 61(4), 803–814. https://doi.org/10.3311/ppci.10540. eric, r., moss, s., & crosariol, v. a. (2013). scale model shake table testing of an underground tunnel cross section in soft clay. 29(4), 1413–1440. https://doi.org/10.1193/070611eqs162m. ering, p., & sivakumar babu, g. l. (2020). effect of spatial variability of earthquake ground motions on the reliability of road system. soil dynamics and earthquake engineering, 136(december 2019), 106207. https://doi.org/10.1016/j.soildyn.2020.106207. fleming, b. j., eeri, m., sritharan, s., & miller, g. a. (2016). full-scale seismic testing of piles in improved and unimproved soft clay. 32(1), 239–265. 208 ripon hore et al / geosi vol 5 no 2 (2020) 196-209 https://doi.org/10.1193/012714eqs018m. goktepe, f., celebi, e., & omid, a. j. (2019). numerical and experimental study on scaled soil-structure model for small shaking table tests. soil dynamics and earthquake engineering, 119(august 2018), 308–319. https://doi.org/10.1016/j.soildyn.2019.01.016 hamayoon, k., morikawa, y., oka, r., & zhang, f. (2016). 3d dynamic finite element analyses and 1 g shaking table tests on seismic performance of existing group-pile foundation in partially improved grounds under dry condition. soil dynamics and earthquake engineering, 90, 196–210. https://doi.org/10.1016/j.soildyn.2016.08.032. haque, m. e., sayem, h. m., & kamal, m. (2013). assessment of some engineering geological aspects of the sub-soil of ganakbari, dhaka, bangladesh. jahangirnagar university environmental bulletin, 2(september), 61–70. https://doi.org/10.3329/jueb.v2i0.16331. hassan, a., & pal, s. (2018). effect of soil condition on seismic response of isolated base buildings. international journal of advanced structural engineering, 10(3), 249–261. https://doi.org/10.1007/s40091-018-0195-z. he, t., & jiang, n. (2019). substructure shake table test for equipment-adjacent structure– soil interaction based on the branch mode method. structural design of tall and special buildings, 28(4), 1–19. https://doi.org/10.1002/tal.1573. helwany, s., wu, j. t. h., meinholz, p., alizadeh, v., & ghaderi, r. (2017). seismic behavior of grs bridge abutments with concrete block facing: an experimental study. transportation infrastructure geotechnology, 4(4), 85–105. https://doi.org/10.1007/s40515-017-0040-z. hore, r., arefin, m. r., & ansary, m. a. (2019). development of zonation map based on soft clay for bangladesh. journal of engineering, 10(1), 13–18. hore, r., chakraborty, s., shuvon, a. m., & ansary, m. a. (2020). effect of acceleration on wrap faced reinforced soil retaining wall on soft clay by performing shaking table test. 15, 1–11. krishna, a. m., & latha, g. m. (2007). seismic response of wrap-faced reinforced soilretaining wall models using shaking table tests. geosynthetics international, 14(6), 355– 364. https://doi.org/10.1680/gein.2007.14.6.355. kumar, v., chopra, s., choudhury, p., & kumar, d. (2020). estimation of near surface attenuation parameter kappa (κ) in northwest and northeast himalaya region. soil dynamics and earthquake engineering, 136(september 2019), 106237. https://doi.org/10.1016/j.soildyn.2020.106237. latha, g., & krishna, a. (2006). shaking table studies on reinforced soil retaining walls. indian geotechnical journal, 36(4), 321–333. madhavi latha, g., & manju, g. s. (2016). seismic response of geocell retaining walls through shaking table tests. international journal of geosynthetics and ground engineering, 2(1), 1–15. https://doi.org/10.1007/s40891-016-0048-4. srilatha, n., latha, g. m., & puttappa, c. g. (2013). effect of frequency on seismic response of reinforced soil slopes in shaking table tests. geotextiles and geomembranes, 209 ripon hore et al / geosi vol 5 no 2 (2020) 196-209 36(september 2014), 27–32. https://doi.org/10.1016/j.geotexmem.2012.10.004. srinivasan, v., srivastava, s., & ghosh, p. (2016). optimization and parametrical investigation to assess the reconstitution of different types of indian sand using portable travelling pluviator. geotechnical and geological engineering, 34(1), 59–73. https://doi.org/10.1007/s10706-015-9928-y. suzuki, m., shimura, n., fukumura, t., yoneda, o., & tasaka, y. (2015). seismic performance of reinforced soil wall with untreated and cement-treated soils as backfill using a 1-g shaking table. soils and foundations, 55(3), 626–636. https://doi.org/10.1016/j.sandf.2015.04.013. xiao, m., ledezma, m., & hartman, c. (2014). shake table test to investigate seismic response of a slurry wall. geotechnical special publication, 234 gsp, 1234–1243. https://doi.org/10.1061/9780784413272.120. yazdandoust, m. (2017). investigation on the seismic performance of steel-strip reinforcedsoil retaining walls using shaking table test. soil dynamics and earthquake engineering, 97(november 2016), 216–232. https://doi.org/10.1016/j.soildyn.2017.03.011. ye, j., & jiang, l. (2018). simplified analytical model and shaking table test validation for seismic analysis of mid-rise cold-formed steel composite shear wall building. sustainability (switzerland), 10(9). https://doi.org/10.3390/su10093188. zhou, y., wang, h., wen, r., ren, y., & ji, k. (2020). insights on nonlinear soil behavior and its variation with time at strong-motion stations during the mw7.8 kaikōura, new zealand earthquake. soil dynamics and earthquake engineering, 136(29), 106215. https://doi.org/10.1016/j.soildyn.2020.106215. 288 revi mainaki et al / geosi vol 5 no 2 (2020) 288-300 land value potential zonation : implication towards urban planning revi mainaki1, anita eka putri1*, dwiyono hari utomo2 1department of geography education, faculty of teacher training and education, universitas siliwangi, jl. siliwangi no. 24, kota tasikmalaya 46115, indonesia 2department of geography education, faculty of social science, universitas negeri malang, jl. semarang 5, malang, 65145, indonesia *corresponding author : anita.eka@unsil.ac.id received 15 april 2020/ revised 7 august 2020 / accepted 15 august 2020/ available online 22 august 2020 abstract potential land prices are strongly influenced by various factors, cimahi city has three subdistricts displaying unique characteristics, since it is located between two districts and one large city, which affects the potential price of land. the potential price of land is crucial to identify, especially in determining the policies of related agencies, the purpose of this research was to zoning potential land prices in cimahi city. this study engaged a quantitative approach utilizing data collection technique in the form of observation, literature, documentation, and interviews, then analysis was conducted using a gis which composed of assessment, weighting, coating, and buffering. the study population was all sub-districts in cimahi. the research samples were taken from several sub-districts which were influenced by districts and cities characteristics indicators such as accessibility, land usage, and land ownership status. the results showed land prices potential was classified as low, medium, and high which was derived by several indicators. it could be concluded that the potential land price is strongly influenced by the surrounding area features, especially urban and district infrastructure. . keywords: land value potential; zonation; urban planing 1. introduction land is needed by humans for all forms of activities, especially for living and farming to meet their daily needs. land ownership in indonesia have been regulated in government policy related to the start of laws, legislation, government regulations, presidential regulations, presidential decrees and other technical rules (virgo et al., 2011). cimahi city presents unique characteristics to investigate how the land price is predicted, since cimahi city is one of the bearers and directly adjacent to the city of bandung with proximity of 12 km as the capital of west java province. cimahi city is bordered by bandung regency and west bandung regency in the other side. ownership along with rapid development are determining the value of a particular currency, the more strategic or the closer residence to meet human needs, certainly the higher it gets to be paid. land prices are mainly drived by several factors (anggraini et al., 2015; geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.5 no. 2 (2020), 288-300, august, 2020 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v5i2.17442 accredited by the ministry of research , technology , and higher education of the republic of indonesia, no. 30/e/kpt/2019. mailto:anita.eka@unsil.ac.id https://jurnal.unej.ac.id/index.php/geosi https://drive.google.com/file/d/1rsnvas6cuhowhl5bj87cl2l6k5dqz7s6/view 289 revi mainaki et al / geosi vol 5 no 2 (2020) 288-300 glaeser et al., 2005) namely (1) physical factors such as soil type, slope, elevation, land area and land utilization; (2) economic factorssuch as purchasing power, interests, amount of benefits offered, interest rates and land beneficial; (3) social factors namely population, security level and community lifestyle; (4) government factors namely taxes and related policies; (5) location and accessibility such asaccessibility towards education, health facilities, main roads, markets, transportation, mobility pace and etc; (6) availability of facilities for electricity networks, clean water, telephone networks, religious amenities, education, health and the tranquil spots. a study result indicated that land prices are drawn by several factors (fakhirah, 2010; hidayanti, 2013) as follows (1) distance aspect upon road accessibility; (2) elevation aspect which correlates to temperature and water; (3) distance towards donwtown or main activities spots; (4) zoning; (5) mobility pace; (6) land topography; (7) land area, and (8) land usage types. the land classification scheme to determine the price of land in a certain parameter including land purposed for (1) settlements; (2) trade and services; (3) industry; (4) transportation, communication and facilities; (5) a relatively complex trading industry; 6) urban areas within downtown and (7) urban areas within urban areas (rusdi, 2013; prabowo et al., 2016; sasono & susetyo, 2018; prihandoko, 2018). land prices would possibly increase in accordance to the occurrence of economic activity that is correlated towards infrastructure such as roads, government financial and other activities in centrals (rynjani & ragil, 2015). the significant of zoning as a form of reconstruction is to estimate the potential price and to determine certain area performing a spatial approach. a research showed how zoning could be utilized as basic decision-making theories of the region's level of urgency (hermawan & mainaki, 2019). zoning could also be conducted using basic relics and other object indicators with reconstruction principle to determine the potential or forecasts of a particular are (mainaki & hermawan, 2019). once the zoning results are identified, the results are not only beneficial for decision making, but also could be used as a learning resource, as the map becomes a basis in identifying an area as a whole, to compherend the thoughts that would foster spatial intelligence. the results of this study could be used as one of the additional indicators in determining the purchase of shelter for the community in cimahi as one of the growing centers (hilman & mainaki, 2020; rahayu & haryatiningsih, 2013). the other side of cimahi is bordered by west bandung regency, which is a new administrative area that has expanded, only a few years since the district was formed. this 290 revi mainaki et al / geosi vol 5 no 2 (2020) 288-300 feature establishes the city of cimahi occupies urban areas both within the middle of urban and in the suburbs. it has a relatively diverse area with social characteristics and physical potential, therefore land utilization determines the price of the land is relatively varied and has not been zoned in a wider scope area. hence, land price predictions in cimahi city which are essential information for urban planning and management (koka et al., 2013). a few researchers focused on development, since the potential price of land turns high or low. there have been limited studies concerned on a smaller scale and rarely utilized a regional approach, which was a draw back if a study attempted to analyze particular zone or region. therefore, this current study aimed to describe the potential price of land in the form of reports and zoning maps engaging scoring and weighting on gis, the purpose of this research was to zoning potential land prices in cimahi city. 2. methods in order to analyze the potential of land prices in the city of cimahi, this study employed a quantitative research approach using procedural steps based on the geographic information system (gis). the basic analysis was performed for potential prices which later used as a feasibility study, as the indicators used in the study were based on relevant agency documentation research (putri et al., 2020) namely (1) preliminary study to determine the topic, issues formulation, objectives and results to be obtained; (2) determine the research methodology and instruments development in accordance to collected data; (3 ) data collection was gained by documentation method were taken from (a) national land agency (bpn) of cimahi city to obtain data regarding land ownership status, land use and land area, (b) cimahi city transportation agency to obtain data relating to the existing road network in the city; supported by literature review and field observations based on documentation data to identify and strengthen research results referring to various scientific references, hence the basis of zoning grows vivid as it is founded upon theory (mainaki & putri, 2020) data processing obtained relation upon the geographic information system (gis) includes (a) scoring; (b) weighting; (c) determining the maximum score and weight to identify the range of scores (kusumo & nursari, 2016; gunawan et al., 2014; siagiaan et al., 2015). the analysis unit in this study was urban villages, thus the population was all urban villages in cimahi city and the sample was several urban villages that displayed similar characteristics of one to two district. the potential land prices were determined using scoring 291 revi mainaki et al / geosi vol 5 no 2 (2020) 288-300 and weighting tables (table 1, table 2, table 3, table 4, table 5), the higher score means the higher potential land price and vice versa as the basis of map overlay is presented below: table 1. the process of scoring data based on the area of the land or building no. land use large large (>10000 m²) is being (1000-10000 m²) narrow (<1000m 2 ) 1. rice fields 3 2 1 2. plantation 3 2 1 3. offices/schools/hospitals/health centers 3 2 1 4. factory/industry 3 2 1 5. shops/supermarkets/markets 3 2 1 6. settlements 3 2 1 7. empty land 1 1 1 (source: 2019, analysis results) table 2. the process of scoring data based on land utilization no. land use score 1. rice fields, plantations and vacant land 1 2. offices/schools/hospitals/health centers and settlements 2 3. shops/supermarkets/markets and factories/industries 3 (source: 2019, analysis results) table 3. the process of scoring (scoring) data based on accessibility no. road type score close (<50 m) is being (50-100 m) far (> 100 m) 1. distance to frontage road 3 2 1 2. distance to boulevard 3 2 1 3. distance to provincial road 3 2 1 (source: 2019, analysis results) table 4. process of scoring data based on mastery of land ownership no. criteria score 1. right to use (tni hp) 1 2. right of use (mobile) 2 3. right to build (hgb) 2 4. customary property/rights (hm/hma) 3 (source: 2019,analysis results) table 5. the process of weighting (weight) based on map effect no map weight information 1 land use 3 the type of use and area of land greatly influences the value of land and impacts on prices and determination of tax rates. 2 road network 3 affordability of land affects the value of the land and the calculation of the tax rate. 3 land tenure 2 to identify land tenure (property rights or state property) in determining taxes. (source: 2019, analysis results) 292 revi mainaki et al / geosi vol 5 no 2 (2020) 288-300 the overlay calculation for zonation is performed as follows: minimum total score = (minimum score of land area x minimum weight of land use map) + (minimum land use score + minimum weight of land use map) + (minimal score of adjacency to road x minimum weight of road network map) + (minimum land mastery score x minimum weight of status map land) minimum total score = (1x3) + (1x3) + (1x3) + (1x2) = 3 + 3 + 3 + 2 = 11 maximum total score = (maximum land area score x maximum weight of land use map) + (maximum land use score + maximum weight of land use map) + (maximum score of adjacency to road x maximum weight of road network map) + (maximum score of land mastery x maximum weight of status map land) maximum total score = (3x3) + (3x3) + (3x3) + (3x2) = 9 + 9 + 9 + 6 = 33 zonation range : = ∑𝑀𝑎𝑥𝑖𝑚𝑎𝑙 𝑆𝑐𝑜𝑟𝑒 − ∑ 𝑀𝑖𝑛𝑖𝑚𝑢𝑚 𝑆𝑐𝑜𝑟𝑒 𝐶𝑎𝑡𝑒𝑔𝑜𝑟𝑦 (1) = 33−11 3 = 7.33 rounded 7 hence, the zonation range is: 11 to 18 = low land price potential; 19 to 26 = potential medium land prices; 27 to 33 = potential high land prices. 3. results and discussion land utilization in the city of cimahi (figure 1) presented practically similar characteristics of land use in each village that was dominated with settlements, rice fields and plantations. however, in the south side were relatively large industrial and shopping areas which indicated on how the southern part gained the potential for higher land prices compared to central and northern parts. the northern part is bordered by west bandung regency while the southern part is bordered by bandung city. hence, considering both the land utilization and location, the south side seemed promising higher price potential and vice versa occurred upon the north that obtained lower price potential. the road network in cimahi (figure 1) has been relatively wide-spread, as each place was connected with local avenue and highway. the central part was cut across over provincial road in a single direction, that way the south was remarkably more strategic than north. the south was through fare towards provincial road one-way and two-way, making it more strategic than the central and northern parts of cimahi. this phenomenon explains why 293 revi mainaki et al / geosi vol 5 no 2 (2020) 288-300 the south has higher potential land prices according to the road network adjacency and accessibility upon low to high, namely the north, center and south. according to land ownership status (figure 1) in the north and south, most of them earned the land ownership/customary ownership rights status. in the southern part obtained land utilization rights, where the central part obtained of land use rights status (military),as cimahi as a military basis in the sense of the community implying that the middle part was inventory or land of country that was only function for military. the northern and southern displayed interests for the benefit upon other human activities, means the northern and southern parts will likely draw a higher potential land price compared to the central part of cimahi city. potential land prices (figure 2) in the north or cimahi utara sub-district used pasirkaliki sub-district as sample possed regular or irregular residential or irregular land use conditions and rice fields, the land use status of all customary property rights. this urban village presented practically similar characteristics as other urban villages in north cimahi sub-district. it endowed potential high land prices of customary property rights status, in term of residential or regular land utilization and relatively adjacent towards the road based on distance factor, while areas with potential taxes were customary land/customary land status with regular and relatively moderate or far-off residential land use by road. based on the analysis conducted to the middle section with setiamanah village as a sample that displayed identical characteristics towards other urban villages within central cimahi sub-district, it could be concluded that setiamanah and other urban villages within the central part of cimahi city enjoyed high and medium land prices, most of which were potentially due to land use of military status of usufructuary rights (government land). the other minority gained high potential price, since those earned customary land/customary rights status. the sample of the southern part or the southern district of cimahi in the current study was the cibeber village, with land status, land use and various road conditions as appeared in other villages in the southern part of cimahi city. the administrative map, land status, land use and road network of cimahi city is presented be on figure 1. 294 revi mainaki et al / geosi vol 5 no 2 (2020) 288-300 figure 1. administrative map, land status, land use and road network of cimahi city revi mainaki et al / geosi vol 5 no 2 (2020) 288-300 figure 2. map of land use, land status, potential land prices in pasirkaliki, setiamanah and cibeber villages in cimahi city 295 296 revi mainaki et al / geosi vol 5 no 2 (2020) 288-300 cibeber sub district demonstrated a relatively diverse land prices potential (figure 2). the potential high price was expected for land with customary property rights status, strategically adjacent towards one or two-way provincial roads, supported with residential and industrial/market land use. land use is the land with right to establish building or military base, while the potential for low land prices was presented with the condition upon usufructuary land status of employment for paddy fields or plantations and relatively remote towards the main road in accordance with the direction of proximity to the road. considering the influence of land status, land use, adjacency, and land accessibility, cimahi city endowed potential of land prices across north to south. in the north side was potentially possess low prices, while in the south showed higher value, and in middle had more diverse potential land prices. the map of landuse, land status, and potential land prices in pasirkaliki, setiamanah and cibeber village in cimahi city is presented on figure 2. the results showed that potential for the low, medium and high land potential prices within cimahi city were strongly influenced whether by road network or land utilization in the term of urban village surroundings. land status affects the land prices potential, however not by two other aspects. this result is in accordance with research conducted by fakhirah (2010) and hidayanti (2013) which land prices were drawn by (1) distance aspect towards road accessibility; (2) elevation aspect that relates to temperature and water; (3) accessibility towards center of activities or activities; (4) zoning; (5) mobility pace; (6) land topography; (7) land area and (8) land use type. the result also comformable towards rusdi (2013); prasetya & sunaryo, (2013); sasono & susetyo (2018); prihandoko (2018) which described the land classification scheme to determine the land price in a certain parameter, namely land use for (1) settlements; (2) trade and services; (3) industry; (4) transportation, communication and facilities; (5) a relatively complex trading industry; (6) urban areas within downtown and (7) urban within the urban areas. the results showed the correlation between several studies in a single result with a specific area and broader approach (regional approach). this result is in accordance with research conducted by elmanisa et al. (2017) examined land prices across jakarta, bogor, depok, tanggerang and bekasi or abbreviated as jabodetabek illustrated how land prices in these areas were relatively high due to resources and infrastructure, especially within metropolitan area of the capital. in indonesia, there are several areas with zoning potential for research land, as urban areas in cimahi city gained relatively high land prices which tended to be close to bandung city as the capital area of 297 revi mainaki et al / geosi vol 5 no 2 (2020) 288-300 west java province and otherwise, it tended to below or moderate once the areas were rather remote towards bandung city or closer to urban areas. this research is also in line with the research of hidayanti (2013) that engaged highresolution satellite image analysis to zoning land prices in jetis district, yogyakarta utilizing relatively similar indicators. the results are quite equal, which strengthened the research results of cimahi city with relatively similar results are obtained. therefore, the results of this study could be utilized as a general reference for upcoming research regarding zoning potential land prices in various regions. in contrast to research of masykuroh & rudiarto (2016) which attempted on changes in land prices, as there was an effect highway development, in this case is accessibility aspect. there was an increase of land prices towards the area nearby the road or highway gate of ungaran. the result supports the research undertaken,since accessibility aspect significantly affects the potential price of land. research of rahati et al. (2015) is also in line with this study, as the occurrence of land damage due to natural disasters had greatly reduced land prices, certainly, it is related to the physical aspect that is being affected by the damage and causes material loss. based on the research discussions according to several other studies, this study presents a parallel and general position, what distinguishes this study from other research is that the location demonstrates intriguing characteristics. in this study of cimahi city, which represented an area that obtain characteristics established upon cities and districts. 4. conclusion all over areas in cimahi city obtained a road construction network that was relatively evenly crossed by city roads, sub-district roads and provincial roads. the southern part of cimahi city possed an area that was supported with bandung city namely factories, shophouses and industrial areas, where the land status was dominated by ownership and user rights,therefore most land prices were relatively high. the central area was dominated by settlements and military areas utilization with land status dominated by military rights. hence, most areas displayed the potential for moderate land prices as those were the central controlled by municipalities or regencies, while the northern part was dominated by open land use such as plantations and land. rice fields ownership and use rights, thus most of the potential land prices were low and moderate due to excess, by the district area. 298 revi mainaki et al / geosi vol 5 no 2 (2020) 288-300 conflict of interests the authors declare that there is no conflict of interest with any financial, personal, or other relationships with other people or organizations related to the material discussed in the article. acknowledgment we would like to express our gratitude to universitas pendidikan indonesia, specifically bachelor degree programs that have provided us opportunities to perform research and formulated the journal articles. references anggraini, s., prawira, y. c. s., untung, m., & indonesia, p. (2015). estimated the reasonable land price in industrial estate : case study of an industrial estate in jakarta. fig working week. sofia, bulgaria. elmanisa, a. m., kartiva, a. a., fernando, a., arianto, r., winarso, h., & zulkaidi, d. (2017). land price mapping of jabodetabek, indonesia. geoplanning: journal of geomatics and planning, 4(1), 53-62. fakhirah. (2010). identifikasi faktor yang mempengaruhi nilai jual lahan dan bangunan pada perumahan tipe sederhana. jurnal smartek, 8(4), 251–269. glaeser, e. l., gyourko, j., & saks, r. (2005). why is manhattan so expensive? regulation and the rise in housing prices. journal of law and economics, 48(2), 331–369. https://doi.org/10.1086/429979. gunawan, d; hartanti, s & maulana, y. (2014). rancang bangun aplikasi analisis kredit menggunakan metode skoring pada bintang jaya variasi audio. jurnal sistem informasi, 3(2), 97–103. hermawan, i & mainaki, r. (2019). pemetaan jalur dan tinggalan perkeretaapian masa kolonial belanda di wilayah cirebon timur. jurnal sosioteknologi, 18(3), 560–574. hidayanti, i. (2013). analisis harga lahan berdasarkan citra penginderaan jauh resolusi tinggi. jurnal pendidikan geografi gea, 8(4), 57–71. hilman, i & mainaki, r. (2020). advantage of map as geography learning media to enhance students spatial intelligence. internasional journal of geomate, 18(68), 225– 232. koka, n; monkkonen, p & quigleyc, g. (2013). land use regulations and the value of land and housing; an intra-metropolitan analysis. journals of urban economic, 81(2), 136–148. https://doi.org/https://doi.org/10.1016/j.jue.2014.03.004. kusumo, p & nursari, e. (2016). zonasi tingkat kerawanan banjir dengan sistem informasi 299 revi mainaki et al / geosi vol 5 no 2 (2020) 288-300 geografis pada das cidurian kabupaten serang, banten. jurnal string, 1(1), 29–38. rahati, m., kahar, s., & subiyanto, s. (2015). analisis perubahan zona nilai tanah kaitannya dengan banjir di kecamatan pedurungan kota semarang. jurnal geodesi undip, 4(1), 117-128. mainaki, r & hermawan, i. (2019). perkeretaapian masa kolonial belanda di wilayah indramayu: pemetaan jalur dan bukti tinggalan arkeologis. jurnal walennae, 17(2), 125–142. mainaki, r & putri, a. (2020). paleogeografi: perkembangan keanekaragaman hayati dalam ruang dan waktu (biodiversity in time and space). jurnal geografi, edukasi dan lingkungan, 4(1), 17–24. masykuroh, d. k., & rudiarto, i. (2016). kajian perubahan penggunaan lahan dan harga lahan di wilayah sekitar pintu tol ungaran. tataloka, 18(1), 53-66. prabowo, s., hamid, d., & prasetya, a. (2016). analisis partisipasi masyarakat dalam pengembangan desa wisata (studi pada desa pujonkidul kecamatan pujon kabupaten malang). jurnal administrasi bisnis s1 universitas brawijaya, 33(2), 18–24. prasetya, n & sunaryo, b. (2013). faktor-faktor yang mempengaruhi harga lahan di kawasan banjarsari kelurahan tembalang, semarang. jurnal teknik pwk, 2(2), 223– 232. prihandoko, t. (2018). analisis nilai lahan kecamatan mergangsan kota yogyakarta menggunakan aplikasi sig dan penginderaan jauh. jurnal pendidikan geografi ums, 13(1), 1–14. putri, a. e., utomo, d. h., & mainaki, r. (2020). analisis kesesuaian lahan rawa untuk pengembangan kawasan permukiman di kecamatan gondang kabupaten tulungagung. jurnal pendidikan geografi: kajian, teori, dan praktek dalam bidang pendidikan dan ilmu geografi, 25(2), 170-178. rahayu, m & haryatiningsih, r. (2013). persepsi masyarakat dalam menentukan tempat tinggal : kota cimahi sebagai pusat pertumbuhan. jurnal kajian ekonomi dan pembangunan, 9(2), 58–71. https://doi.org/doi: https://doi.org/10.29313/.v9i2.2305. rusdi, m. (2013). faktor-faktor yang mempengaruhi harga dan penggunaan lahan di sekitar jalan lingkar salatiga. jurnal pembangunan wilayah dan kota, 9(3), 317–329. https://doi.org/https://doi.org/10.14710/pwk.v9i3.6543. rynjani, g & ragil, h. (2015). kajian harga tanah dan penggunaan lahan di kawasan perdagangan dan jasa kelurahan lamper kidul, kota semarang. jurnal teknik pwk, 4(3), 417–427. sasono, m & susetyo, c. (2018). analisis potensi perubahan pemanfaatan lahan berdasarkan model spasial harga lahan di kecamatan tembelang kabupaten jombang. jurnal teknik its, 7(1), 60–65. 300 revi mainaki et al / geosi vol 5 no 2 (2020) 288-300 siagiaan, t; sudarsono, b & wijaya, a. (2015). evaluasi kriteria kesesuaian lahan permukiman dengan analitycal hierarchy process (studi kasus :kecamatan boja dan kecamatan limbangan di kabupaten kendal). jurnal geodesi undip, 5(1), 107–115. virgo, e; mahendra, a; rusmawar, w & jp, t. (2011). land value indexation in indonesia: a pilot study in pontianak city. facing the challenges-building the capacity congress. proceeding fig congress. fix-dikonversi_3.pdf (p.1-6) 1 hal fix (1) edited.pdf (p.7) 2 hal fix edited.pdf (p.8) fix-dikonversi_2.pdf (p.9-13) r. sanjeeva reddy et al /geosi vol 5 no 3 (2020) 335-351 335 geospatial approach for the analysis of forest cover change detection using machine learning r. sanjeeva reddy1,*, g. anjan babu1, a. rama mohan reddy2 1 department of computer science, sri venkateswara university, tirupati, andhra pradesh, 517502, india 2 department of computer science & engineering, sri venkateswara university, tirupati, andhra pradesh, 517502, india *corresponding author : haisanjeevareddy@gmail.com received 13 october 2020/ revised 11 december 2020 / accepted 24 december 2020/ published 30 december 2020 abstract spatial data classification is famous over recent years in order to extract knowledge and insights into the data. it occurs because vast experimentation was used with various classifiers, and significant improvement was examined in accuracy and performance. this study aimed to analyze forest cover change detection using machine learning. supervised and unsupervised learning methods were used to analyze spatial data. a vector machine was used to support the supervised learning, and a neural network method was used to support unsupervised learning. the normalized difference vegetation index (ndvi) was used to identify the bands and extract pixel information relevant to the vegetation. the supervised method shows better results because of its robust performance and better analysis of spatial data classification using vegetation index. the proposed system experimentation was implemented by analyzing the results obtained from support vector machine (svm) and nn (neural network) methods. it is demonstrated in the results that the use of ndvi mainly enhances the performance and increases the classifier's accuracy to a greater extent. keywords: spatial data; normalized difference vegetation index; ndvi;vegetation index, support vector machine; neural network; forest cover change 1. introduction the knowledge of various social, economic, and cultural aspects is considered a correct viewpoint in land management and its planning. in various scenarios, landscape changes did not show up ultimately. therefore, to give exceptional improvement to the lands, different geographic tools are used such as geographic information system and photogrammetry. the point judges of the criteria of forest management that the population is decreasing in some regions. therefore, most of the land is covered with trees and bushes, seriously affecting the landscape (an et al., 2007). to describe the data and gather useful geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.5 no. 3 (2020), 335-351, december, 2020 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v5i3.20157 accredited by the ministry of research , technology , and higher education of the republic of indonesia, no. 30/e/kpt/2019. geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.5 no. 3 (2020), 301-317, december, 2020 https://jurnal.unej.ac.id/index.php/geosi doi : accredited by the ministry of research , technology , and higher education of the republic of indonesia, no. 30/e/kpt/2019. https://jurnal.unej.ac.id/index.php/geosi https://drive.google.com/file/d/1rsnvas6cuhowhl5bj87cl2l6k5dqz7s6/view https://jurnal.unej.ac.id/index.php/geosi https://drive.google.com/file/d/1rsnvas6cuhowhl5bj87cl2l6k5dqz7s6/view r. sanjeeva reddy et al /geosi vol 5 no 3 (2020) 335-351 336 information regarding the earth's surface, geographic information has been considered as a fruitful source. there are various applications involved, such as digital image analysis, analysis, and detection of a change in environmental conditions, science, education. however, these areas are a source of the right domain to conduct adequate research. geospatial approach for the analysis of forest cover change detection using machine learning. the spatial data is gathered from satellites that include images and define information regarding the image's pixels. the data collected seems unstructured and complex, and then this data is evaluated to get that hidden information. this process is mainly called spatial data analysis, and to get and relocate the landscape in spatial data is known as geospatial data analysis. these landscape types are identified and classified by utilizing techniques that involve deep learning and machine learning. svm is one of the adequate mechanisms used in ml, and in it, the kernel function is activated to conduct the descriptive analysis on the dataset of images. the features are extracted and based on those features, and the machine classifies the landscape types. the main landscape types involved are bare soil, urban land, waterbody, natural vegetation, and forest area. the spatial data gathered was very difficult to cater to, and it involves various critical issues regarding orientation, structure, and other atmospheric conditions (aubrecht et al., 2009; addink et al., 2007). the ongoing writing study on distant detecting information, characterization utilizing ai techniques incorporates the rich data regarding the spatial information focal points, natural biology, accuracy farming, science and building, and military use. recently, the distant detecting information characterization has been finished utilizing better ai and profound learning approaches (pozdnoukhov & kanevski, 2006). the diverse order strategies were utilized on far off detecting information. in high dimensional space, the impediment of dimensionality may yield excellent outcomes. the high dimensional information dealing with is a fundamental task in the enhancement issues (gangappa et al., 2016). subsequently, the enhancement technique, such as svm may regularly be unaware of high dimensional space (acharya & yang, 2015). there is numerous grouping calculation which is regularly used to anticipate the class objects in the spatial data. the regulated learning techniques for spatial information are neural networks, choice tree technique, irregular timberlands order techniques, k-implies bunching and arrangement strategy, harsh set based information decrease and characterization technique, and fuzzy rough set based order method (singh et al., 2016; chi et al., 2008; pal, 2005). the fluffy rationale and neural networks are utilized in spatial information characterization. the r. sanjeeva reddy et al /geosi vol 5 no 3 (2020) 335-351 337 adequate measure of research work commitment has been on fluffy and unpleasant based components (shanthini et al., 2017; foddy & mathur, 2004; al-obeidat et al., 2015; ham et al., 2005). numerous different calculations have been utilized in advancement issues. in the graphic models, the preparation information with class marks was given at preparing a calculation. in request to get prepared, these techniques (rawat & kumar, 2015) utilize some spatial information highlights, for example, spatial goal, entropy, mean eleven and mean slop, and other pertinent highlights in the input information. we firmly contend that expectation exactness depends on the noteworthy highlights utilized in that model. various machine learning techniques were used to identify different landscape images, and they are considered supervised learning. it involves training data, and the classifier learns from the training data, and other decisions are mainly based on the lear ning of the classifier. the classifier was done its training based on the features extracted. sometimes more the faster features are the classifier's efficiency; however, the feature's amount may affect the classifier performance in some cases. as we can say, the classifier takes more time to validate those features of the dataset gathered, and the performance of the system falls. this may also lead to affect the accuracy of the classifier badly. therefore, for this purpose and feature extraction, some feature reduction techniques are also being involved in the classification process. dimensionality reduction is used to make the dimension space more accurate for the spatial data. ultimately, we emphasize the evaluation of machine learning methods suitable for spatial data pixels. this study aimed to analyze forest cover change detection using machine learning. this research also aimed to find out suitable machine learning techniques that efficiently extract the features, reduce the features according to the demand, and distinguish the features based on the dataset's pixel information. 2. methods 2.1 supervised and unsupervised learning in supervised learning, labeling is involved, in which there is a specific outcome against each entity. furthermore, based on those outcomes, the algorithm accuracy is computed. while on the other hand, in an unsupervised approach, unlabeled data is provided in which the patterns are formed based on the features extracted. this study aimed to analyze forest cover change detection using machine learning. r. sanjeeva reddy et al /geosi vol 5 no 3 (2020) 335-351 338 2.1.1 supervised learning supervised learning contains a properly labeled dataset and then train the algorithm based on this labeled data (mahmon & ya'acob, 2014). the term fully labeled means that the training dataset contains answers to each question or query. a complete illustration of labeled data and its supervision through supervised learning is shown in figure 1. for example, as related to this study, the forest images are labeled according to the years and their specific characteristics, and then after classification, it is to be identified which ones belong to specific families. when the model is fully trained, it is tested on a new set of images, and the models have to predict values against each set of images fed into it. figure 1. algorithm learns labelled data with supervised learning the support vector machine (svm) is a supervised learning method, and they automatically analyze data, make classes, and put each object into a class by using some rules (gangappa et al., 2017). in svm, labeled data is manipulated for all the classes to be the data classified. the following equations (equation 1 and equation 2) for the svm are as follows: 1 1i iu w l for v      (1) 1 1i iu w l for v      (2) r. sanjeeva reddy et al /geosi vol 5 no 3 (2020) 335-351 339 supervised learning is mainly used in two scenarios, one in the classification problems and the other in the regression problems. in classification problems, the prediction of values is made by the classifier in which data is recognized based on class. while in regression problems gather continuous data, and in it, the effect of one variable on the variable is identified, such as for a particular value x, what would be the expected value of the variable y. 2.1.2 unsupervised learning in contrast to supervised learning, unsupervised learning contains a deep learning model with a set of instructions on what to do next. in the training dataset, no labeling is involved, and the dataset is without any desired outcome. the network automatically gets the useful features and then analyzes the structure based on the features extracted. the illustration of unsupervised learning is given in figure 2. figure 2. illustration of unsupervised learning the unsupervised scenario data is arranged in two ways, either by arranging clustering or association, which are deeply explained as follows: (1) clustering: in clustering, the data is divided into clusters or groups having the same properties. based on those features or properties, the images are identified and put in their respective groups, which is mathematically explained in equation 3. for example, it is somehow not possible in different scenarios to distinguish the plants or trees based on their appearance. such as all plants have left and stems branches. furthermore, in clustering, these features (equation 3) are locked in different groups. 2 1 1 ( ) (|| ||) mzz m n m n j b a b     (3) || ||m na b  distance among ix and jv , mz total data points, z total cluster centers. r. sanjeeva reddy et al /geosi vol 5 no 3 (2020) 335-351 340 (2) association: in this way, the algorithm tries to learn without the data being labeled. the algorithm takes some different decisions, such as the forest images are not labeled according to their specific characteristics and fed into the classifier. this is a case of an association, in which highlights of an information test associate with different highlights. by taking a gander at a couple of crucial characteristics of an information point, a solo learning model can foresee different properties with which they are ordinarily related (maity, 2016). the dataset used in this study was landsat 8, and it consists of earth images based on two mechanisms, which are operational land imager oli and thermal infrared sensor trs (lu & yang, 2009). data were collected near the infrared and panchromatic band. the dataset collected consists of various landscape types such as vegetation area, water area, and bare land. more details of the dataset used are illustrated in table 1. table 1. dataset used with respect to its attributes different attributes of dataset used values related to those attributes image format geo tiff orientation north up (map) pixel size 30 meters the data is gathered through remote satellites by using special remote sensors. they mainly reflect the energy on the earth's surface. different types of remote sensors are used, such as spot, landsat, and sar. these sensors contain spectral resolution, and the wavelength represented on the spectral resolution plane is known as the band. different remote sensing systems have different bands. however, in this research work, we have used landsat dataset sensing images, which consists of 11 electromagnetic spectral bands and mainly have 30 meters of spectral resolution. this section presents a framework for spatial data. it contains essential information regarding handling data, evaluating and validating the data to compute useful results. the complete procedure is illustrated in figure 3, as given below. r. sanjeeva reddy et al /geosi vol 5 no 3 (2020) 335-351 341 figure 3. the pipeline of the main classification framework r. sanjeeva reddy et al /geosi vol 5 no 3 (2020) 335-351 342 first, pre-processing is done to make the instructed data in a structured format. in it, the dataset is considered as input. at first, the images are digitized to represent the intensity of each pixel in the spectral band. before starting the primary procedure, the raw data need some extra techniques to be used in order to correct errors and avoid noise. the main techniques involved are radiometric correction, geometric correction, and noise removal. after implying these techniques, the data is aligned to the real-world coordinates. in the next step, the vegetation indices are computed to be implied in different scenarios like climate change, detection, monitoring, and modeling of vegetation studies. this procedure helps in combining the information of different bands, and it is also very fruitful to find ndvi by using the following equation (equation 4). nir red ndvi nir red        (4) the final step is to get the region of interest of the image shape file is created. the training and testing samples are also extracted for classification. then the training model is built by using machine learning techniques. 3. results and discussion when the land data was pre-processed, class labels are generated geometrically, such as water, bare land, and forest. then region of interest is extracted from the image and is saved in the shapefile. moreover, from the shapefile, training samples are collected and used in the building of the model. all the features were combined in a shapefile, and then they are used for classification purposes. the features are were represented by the pixel values having specific intensity. the figures (figure 4 – figure 7) show the innumerable spectral assets, which are extricated from the spatial dataset starting from the year 2005 to 2020. r. sanjeeva reddy et al /geosi vol 5 no 3 (2020) 335-351 343 figure 4. area of land-use in 2005 figure 5. area of land-use in 2010 figure 6. area of land-used in 2015 r. sanjeeva reddy et al /geosi vol 5 no 3 (2020) 335-351 344 figure 7. area of land-used in 2020 the spatial trials are divided into two training and testing sections. the training and testing sections are collected based on 70% and 30% phenomena. the svm and nn models were used in the classification process. the detailed performance of land cover categories of 2005 and 2020 is deeply illustrated in table 2. the model accuracy and other statistics related to ndvi are recorded and shown in figure 8. the mean of land-use (lu)/land cover (lc) and fcc are shown in figures (figure 9 figure 13). figure 8. accuracy and other statistics related to ndvi -0.015 -0.01 -0.005 0 0.005 0.01 0.015 1995 2000 2005 2010 2015 2020 2025 ndvi r. sanjeeva reddy et al /geosi vol 5 no 3 (2020) 335-351 345 table 2. land cover categories related to the area square kilometres and area in percentage from 2000 to 2020 the use of ndvi mainly enhances the performance and increases the classifier's accuracy. this result is in line with the results reported by somching et al. (2020), ramos et al. (2020), ahmad et al. (2020), nachapa et al. (2020), gumma et al. (2020), zurqani et al. 2020), liu et al. (2020) that machine learning can improve accuracy in analyzing land-use and land cover change. land-use change from forest to bare land or rocky land is the most dominant. this result is supported by the findings of mirici et al. (2020), yu et al. (2020), devi et al. (2019), that land-use change from forest to bare land and rocky land is becoming dominant due to urbanization and increasing human needs. land-use change from forest to bare land or rocky land occurred mostly in the northern region (figure 9-figure 13). these changes are caused by human activities that require wood as building material. urbanization also causes the human need for forest wood to increase, especially to build new settlements. furthermore, the accessibility of forest locations is also a factor that causes the conversion of forest land to bare land or rocky land. figure 9. mean of land-use/land cover and fcc of 2000 years 2000 2005 2010 2015 2020 landuse/land cover categories area in (sq km) area in (%) area in (sq km) area in (%) area in (sq km) area in (%) area in (sq km) area in (%) area in (sq km) area in (%) less forested 563.0274 21.4 578.387 22.0 559.8693 21.3 632.1591 24.0 504.6606 19.2 rocky 739.6398 28.1 647.5645 24.6 785.8458 29.9 700.2333 26.6 731.9502 27.8 bare land 644.6781 24.5 564.9028 21.5 634.9212 24.1 573.1749 21.8 530.2575 20.2 water body 60.1938 2.3 52.10608 2.0 51.5898 2.0 43.7445 1.7 37.2285 1.4 forested 621.9 23.7 786.5129 29.9 597.213 22.7 680.1273 25.9 825.3423 31.4 total 2629.4391 100 2629.47328 100 2629.4391 100 2629.4391 100 2629.4391 100 r. sanjeeva reddy et al /geosi vol 5 no 3 (2020) 335-351 346 figure 10. mean of land-use/land cover and fcc of 2005 figure 11. mean of land-use/land cover and fcc of 2010 figure 12. mean of land-use/land cover and fcc of 2015 r. sanjeeva reddy et al /geosi vol 5 no 3 (2020) 335-351 347 ndvi with false color composite (fcc) analyzes land changes with very high accuracy. this result is in line with the results reported by oon et al. (2019), das & pandey (2019), murad & pearse (2018), that the fcc can improve accuracy for vegetation analysis. moreover, the fcc is also able to identify bare land in green color. this result is in line with the results reported by khalil & haque (2018), rajani & varadarajan (2018), sharma et al. (2016), that that the fcc is also able to identify bare land. 4. conclusion the accuracy tends to increase when a new band formed in the slack of spatial image. the svm model performed better than nn method, so we can say that supervised learning increases the system's accuracy and performance compared to unsupervised learning. the classification is performed with the spatial vegetation index related to ndvi. it is also observed that if different vegetation indices are used and evaluated on different datasets, there are great chances that the system's accuracy improves to a large extent. figure 13. mean of land-use/land cover and fcc of 2020 r. sanjeeva reddy et al /geosi vol 5 no 3 (2020) 335-351 348 conflict of interest the authors declare that there is no conflict of interest with any financial, personal, or other relationships with other people or organizations related to the material discussed in the article. references acharya, t. d., & yang, i. (2015). exploring landsat 8. international journal of it, engineering and applied sciences research, 4(4), 4-10. addink, e. a., de jong, s. m., & pebesma, e. j. (2007). the importance of scale in object based mapping of vegetation parameters with hyperspectral imagery. photogrammetric engineering and remote sensing, 73(8), 905–912. https://doi.org/10.14358/pers.73.8.905. ahmad, i., singh, a., fahad, m., & waqas, m. m. (2020). remote sensing-based framework to predict and assess the interannual variability of maize yields in pakistan using landsat imagery. computers and electronics in agriculture, 178 doi:10.1016/j.compag.2020.105732. al-obeidat, f., al-taani, a. t., belacel, n., feltrin, l., & banerjee, n. (2015). a fuzzy decision tree for processing satellite images and landsat data. procedia computer science, 52(c), 1192–1197. https://doi.org/10.1016/j.procs.2015.05.157. an, k., zhang, j., & xiao, y. (2007). object-oriented urban dynamic monitoring a case study of haidian district of beijing. chinese geographical science, 17(3), 236–242. https://doi.org/10.1007/s11769-007-0236-1. aubrecht, c., steinnocher, k., hollaus, m., & wagner, w. (2009). integrating earth observation and giscience for high resolution spatial and functional modeling of urban land-use. computers, environment and urban systems, 33(1), 15–25. https://doi.org/10.1016/j.compenvurbsys.2008.09.007. chi, m., feng, r., & bruzzone, l. (2008). classification of hyperspectral remote-sensing data with primal svm for small-sized training dataset problem. advances in space research, 41(11), 1793-1799. doi:10.1016/j.asr.2008.02.012. das, p., & pandey, v. (2019). use of logistic regression in land-cover classification with moderate-resolution multispectral data. journal of the indian society of remote sensing, 47(8), 1443-1454. doi:10.1007/s12524-019-00986-8. devi, m.s., dewangan, s., ambashta, s. k., jaiswal, a., & kondapalli, s. (2019). recognition of forest fire spruce type tagging using machine learning classification. international journal of recent technology and engineering, 8(3), 4309-4313. doi:10.35940/ijrte.c5176.098319. foody, g. m., & mathur, a. (2004). a relative evaluation of multiclass image classification by support vector machines. ieee transactions on geoscience and remote sensing, 42(6), 1335–1343. https://doi.org/10.1109/tgrs.2004.827257. https://doi.org/10.14358/pers.73.8.905 https://doi.org/10.1007/s11769-007-0236-1 https://doi.org/10.1016/j.compenvurbsys.2008.09.007 r. sanjeeva reddy et al /geosi vol 5 no 3 (2020) 335-351 349 gangappa, m., mai, d., & sammulal, d. (2016). esdas: explorative spatial data analysis scale to predict spatial structure of landscape. international journal of scientific and engineering research, 7(12), 466–472. https://doi.org/10.14299/ijser.2016.12.001. gangappa, m., mai, d. c. k., & sammulal, d. p. (2017). analysis of advanced data mining prototypes in spatial data analysis'. journal of engineering and applied sciences, 12(12), 3213-3219. gumma, m. k., thenkabail, p. s., teluguntla, p. g., oliphant, a., xiong, j., giri, c., . . . whitbread, a. m. (2020). agricultural cropland extent and areas of south asia derived using landsat satellite 30-m time-series big-data using random forest machine learning algorithms on the google earth engine cloud. giscience and remote sensing, 57(3), 302-322. doi:10.1080/15481603.2019.1690780. ham, j. s., chen, y., crawford, m. m., & ghosh, j. (2005). investigation of the random forest framework for classification of hyperspectral data. ieee transactions on geoscience and remote sensing, 43(3), 492–501. https://doi.org/10.1109/tgrs.2004.842481. oon, a., mohd shafri, h. z., lechner, a. m., & azhar, b. (2019). discriminating between large-scale oil palm plantations and smallholdings on tropical peatlands using vegetation indices and supervised classification of landsat-8. international journal of remote sensing, 40(19), 7312-7328. doi:10.1080/01431161.2019.1579944. pal, m. (2005). random forest classifier for remote sensing classification. international journal of remote sensing, 26 (1), 217–222. https://doi.org/10.1080/01431160412331269698. pozdnoukhov, a., & kanevski, m. (2006). monitoring network optimisation for spatial data classification using support vector machines. international journal of environment and pollution, 28(3–4), 465–484. https://doi.org/10.1504/ijep.2006.011223. rajani, a., & varadarajan, s. (2020). lu/lc change detection using ndvi & mlc through remote sensing and gis for kadapa region. cognitive informatics and soft computing (pp. 215-223). springer, singapore. doi:10.1007/978-981-15-1451-7_24. ramos, a. p. m., osco, l. p., furuya, d.e.g., gonçalves, w.n., santana, d.c., teodoro, l.p.r, . . . pistori, h. (2020). a random forest ranking approach to predict yield in maize with uav-based vegetation spectral indices. computers and electronics in agriculture, 178 doi:10.1016/j.compag.2020.105791 rawat, j. s., & kumar, m. (2015). monitoring land-use/cover change using remote sensing and gis techniques: a case study of hawalbagh block, district almora, uttarakhand, india. the egyptian journal of remote sensing and space science, 18(1), 77–84. https://doi.org/10.1016/j.ejrs.2015.02.002 shanthini, d., shanthi, m., & bhuvaneswari, m. (2017). a comparative study of svm kernel functions based on polynomial. int. j. eng. comput. sci., 6(3). https://doi.org/10.14299/ijser.2016.12.001 https://doi.org/10.1109/tgrs.2004.842481 https://doi.org/10.1504/ijep.2006.011223 r. sanjeeva reddy et al /geosi vol 5 no 3 (2020) 335-351 350 sharma, r. c., tateishi, r., & hara, k. (2016). a biophysical image compositing technique for the global-scale extraction and mapping of barren lands. isprs international journal of geo-information, 5(12) doi:10.3390/ijgi5120225. singh, r. p., singh, n., singh, s., & mukherjee, s. (2016). normalized difference vegetation index (ndvi) based classification to assess the change in land-use/land cover (lulc) in lower assam, india. international journal of advanced remote sensing and gis, 5(1), 1963–1970. doi:10.23953/cloud.ijarsg.74. somching, n., wongsai, s., wongsai, n., & koedsin, w. (2020). using machine learning algorithm and landsat time series to identify establishment year of para rubber plantations: a case study in thalang district, phuket island, thailand. international journal of remote sensing, 41(23), 9075-9100. doi:10.1080/01431161.2020.1799450. khalil, r.z., & haque, s. (2018). insar coherence-based land cover classification of okara, pakistan. egyptian journal of remote sensing and space science, 21, s23-s28. doi:10.1016/j.ejrs.2017.08.005. liu, b., gao, l., li, b., marcos-martinez, r., & bryan, b. a. (2020). nonparametric machine learning for mapping forest cover and exploring influential factors. landscape ecology, 35(7), 1683-1699. doi:10.1007/s10980-020-01046-0. lu, k. c., & yang, d. l. (2009). image processing and image mining using decision trees. journal of information science and engineering, 25(4), 989–1003. https://doi.org/10.6688/jise.2009.25.4.2. maity, a. (2016). supervised classification of radarsat-2 polarimetric data for different land features. arxiv preprint arxiv:1608.00501. mahmon, n. a., & ya'acob, n. (2014). a review on classification of satellite image using artificial neural network (ann). in 2014 ieee 5th control and system graduate research colloquium (pp. 153-157). ieee. mirici, m. e., satir, o., & berberoglu, s. (2020). monitoring the mediterranean type forests and land-use/cover changes using appropriate landscape metrics and hybrid classification approach in eastern mediterranean of turkey. environmental earth sciences, 79(21) doi:10.1007/s12665-020-09239-1. murad, c. a., & pearse, j. (2018). landsat study of deforestation in the amazon region of colombia: departments of caquetá and putumayo. remote sensing applications: society and environment, 11, 161-171. doi:10.1016/j.rsase.2018.07.003. nachappa, t. g., ghorbanzadeh, o., gholamnia, k., & blaschke, t. (2020). multi-hazard exposure mapping using machine learning for the state of salzburg, austria. remote sensing, 12(17) doi:10.3390/rs12172757. yu, j., li, f., wang, y., lin, y., peng, z., & cheng, k. (2020). spatiotemporal evolution of tropical forest degradation and its impact on ecological sensitivity: a case study in jinghong, xishuangbanna, china. science of the total environment, 727 doi:10.1016/j.scitotenv.2020.138678. r. sanjeeva reddy et al /geosi vol 5 no 3 (2020) 335-351 351 zurqani, h. a., post, c. j., mikhailova, e. a., cope, m. p., allen, j. s., & lytle, b. a. (2020). evaluating the integrity of forested riparian buffers over a large area using lidar data and google earth engine. scientific reports, 10(1) doi:10.1038/s41598020-69743-z. the final step is to get the region of interest of the image shape file is created. the training and testing samples are also extracted for classification. then the training model is built by using machine learning techniques. 3. results and discussion when the land data was pre-processed, class labels are generated geometrically, such as water, bare land, and forest. then region of interest is extracted from the image and is saved in the shapefile. moreover, from the shapefile, training samples are... the accuracy tends to increase when a new band formed in the slack of spatial image. the svm model performed better than nn method, so we can say that supervised learning increases the system's accuracy and performance compared to unsupervised learnin... 186 lina wahyuni et al / geosi vol 5 no 2 (2020) 186-195 a preliminary study on tsunami disaster in yogyakarta: identification of vulnerability order and components lina wahyuni1*, muh. aris marfai2, m. pramono hadi2 1doctoral program of regional development study program, faculty of geography, gadjah mada university, jl. kaliurang, sekip utara, bulaksumur, yogyakarta, 55281, indonesia 2 regional development study program, faculty of geography, gadjah mada university, jl. kaliurang, sekip utara, bulaksumur, yogyakarta, 55281, indonesia *corresponding author : linawahyuniananda@gmail.com received 10 march 2020/ revised 14 may 2020 / accepted 23 may 2020/ available online 2 june 2020 abstract a tsunami is a disaster that can be hardly estimated. it is a significant concern un since more than 60% of the world's population lives in coastal areas prone to tsunamis, including indonesia. the county community with complex and dynamic plate requires mastering of mitigation strategies as a tsunami preventive effort. understanding the vulnerable elements in risky areas is critical. however, the magnitude of potential disasters cannot be minimized. this study analyzes the tsunami vulnerability in bantul, special region of yogyakarta (diy). the analysis was based on a description of assessment parameters such as land use, the physical condition of the area, social conditions, and availability of infrastructure. the results show that social vulnerability had the most significant impact. keywords: vulnerability, tsunami, bantul, diy 1. introduction a tsunami refers to waves that are faster, taller, and stronger than wind or storm surge (chen & cheng, 2016; rangel-buitrago et al., 2020). it has frequently occurred in the last decade, damaging coastal structures (nandasena et al., 2012). its incidencet on a large scale is relatively less frequent compared to hydrometeorological disasters.the associated waves are unpredictable because they are caused by sudden significant volcanic displacements, initially triggered by earthquakes, landslides, volcanic eruptions, or meteors (al-faesly et al., 2012). on december 26, 2004, a tsunami disaster was triggered by the magnitude of an earthquake with a strength of 9.1 ritcher scale (sr) in the indian ocean. the maximum height of the waves was 30 meters, causing more than 200,000 deaths and massive geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.5 no. 2 (2020), 186-195, august, 2020 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v5i2.17006 accredited by the ministry of research , technology , and higher education of the republic of indonesia, no. 30/e/kpt/2019. mailto:linawahyuniananda@gmail.com https://jurnal.unej.ac.id/index.php/geosi https://drive.google.com/file/d/1rsnvas6cuhowhl5bj87cl2l6k5dqz7s6/view 187 lina wahyuni et al / geosi vol 5 no 2 (2020) 186-195 destruction of property in more than ten countries bordering the indian ocean (grilli 2007, leonard & lucinda, 2014; iverson & prasad, 2007; roshan et al., 2016). on february 27, 2010, a tsunami disaster was triggered by an 8.8 magnitude earthquake of the coast of chile. the waves reached local run-ups of 29 meters high on coastal cliffs (fritz, 2010). on march 11, 2011, a magnitude 9.0 earthquake stroked near the coast of northeastern japan and swept along the coast, penetrating the land with a maximum height of 40 meters (yeh et al., 2013). on september 16, 2015, an 8.3 magnitude earthquake occurred off chile's central coast and triggered a tsunami with a maximum runoff height of 13 meters (contreras-lopez et al., 2016). in thailand, the dock plates at the port of khao lak and the fishing port of the ban nam kem deck were severely damaged by the uplifted pressure due to the indian ocean tsunami of 2004 (ghobarah et al., 2006). the same incident occurred in japan and damaged the sendai port in the tohoku region during the 2011 tsunami (suppasri, 2012). based on the risk analysis conducted by the national disaster management agency (bnpb) in 2012, four major areas have high risk and probability of tsunami, including mentawai, sunda strait, and southern part of java, megathrust south of bali and nusa tenggara, and northern papua region. of the four areas, the south java coast or pansela, has the largest population (bnpb, 2012). due to a large number of residents in this region, the spatial planning along the south coast of java should be based on coastal area disaster mitigation. the coastal area of the bantul regency is prone to tsunami because it is a low lying area designed as one of the national strategic tourism area (hadipour et al., 2019; mcguire, 2020). the existence of south cross road (jjls) increase the strategic value of the coastal areas. it connects the southern coast of java island to the coast of bantul regency. also, the new airport development plan in the coastal area of the kulonprogo regency is next to the regency, which is integrated with national tourism strategic area (kspn) borobudur and road along jjls. generally, airports are encouraged to support the development of kspn borobudur and surrounding areas. this is stated in the national tourism development master plan 2010-2025. figure 1 shows the diy southern coast strategic region. the implementation of spatial planning should be carried out comprehensively, holistically, well-coordinated, integrated, effective, and efficient, focusing on political, economic, social, culture, defense, security, and environmental sustainability (ibrahim & hegazy, 2013). spatial planning needs to be based on the system approach, main function, 188 lina wahyuni et al / geosi vol 5 no 2 (2020) 186-195 administration, activity, and strategic value areas, taking into account the disaster factor (muta'ali, 2014). figure 1. kspn pansela yogyakarta area. source: government regulation number 50 the year 2011 concerning master plan of national tourism development year 2010 2025. the development plan of the southern coastal region, including the bantul area, has encouraged unity in the spatial planning following the risk of the tsunami disaster (balasundareshwaran et al., 2020). this study analyzes the tsunami vulnerability orderbased on the assessment parameters, including land use, the physical condition, social state,and infrastructure availability. 189 lina wahyuni et al / geosi vol 5 no 2 (2020) 186-195 2. methods the identification of dangerous elements in the disaster-prone area is part of mitigation. this aspect was investigated by tanaka, (2008); tanaka et al., (2010); liyanage & lee, (2012); freire et al., (2012); & shibayama et al., (2012). in this research, the risky component was considered a significant factor in mitigation since the magnitude of the disaster cannot be reduced. the assessment of the damage was conducted by identifying and calculating the vulnerability order, including land use, the physical and social condition of the area, availability of infrastructure, and economic. the unit of analysis was the village administration. theidentification of elements at risk within the tsunami danger zone, including physical, social, and economic elements, is a significant step in determining vulnerability order. the parameters used are based on the national disaster management agency (bnpb) regulation no. 2 of 2012 and several previous studies. the research flows as follows. figure 2. research flow 3. results and discussion indonesia is a country prone to the tsunamis, especially in the coastal area that directly faces the meeting layer of eurasia plate, indo-australia, and the pacific, including the western part of sumatra island, the southern part of java island, nusa tenggara, the northern part of papua, sulawesi, maluku, and the eastern part of kalimantan island (bmkg, 190 lina wahyuni et al / geosi vol 5 no 2 (2020) 186-195 2012; mcguire, 2020).the common disaster occurringis a close-range tsunami of around 200 km from the earthquake epicenter. local tsunamis can be caused by earthquakes,slide, and volcanic eruptions (bmkg, 2012). table 2.1 depicts the tsunami history occurring in indonesia. table 1. significant tsunami event in indonesia no year location magnitude total victims 1 1883 krakatau volcano 36,000 2 1833 west sumatera, bengkulu, and lampung 8.8 unreported 3 1938 kal island, bangka 8.5 unreported 4 1967 tinambung 58 5 1968 tambu, southeast sulawesi 6.0 200 6 1977 sumbawa 6.1 161 7 1992 flores 6.8 2,080 8 1994 banyuwangi 7.2 377 9 1996 toli toli 7.0 9 10 1996 biak 8.2 166 11 2000 banggal 7.3 50 12 2004 nangro aceh darussalam 9.0 250,000 13 2006 pangandaraan 7.2 >600 14 2010 mentawai 7.7 >400 source : mardiatno (2008 ) the greatest tsunami in the history of indonesia occurred in aceh on december 26, 2004. it started by the earthquake magnitude of 9.3 sr, which caused a strong shock and fault, stretching from aceh to andaman. the tsunami was attributed to the earthquake with huge losses and 250,000 deaths (mardiatno, 2008). almost all of the tsunami disasters led to material losses and claimed many lives. according to table 2.1, the most recent tsunami occurred in october 25th 2010 in mentawai island, west sumatra. it started with an earthquake of magnitude 7.7 sr, followed by tsunami waves of 3-10 meters. this caused destruction of 77 villages and more than 400 deaths (mardiatno, 2008). bantul regency has ahigh vulnerability because it directly faces the indian ocean. additionally, the coastal typology tends to be flat (trihatmoko, 2017; mcguire, 2020). when a tsunami strikes, it is likely to damage the physical and social aspects, as well as the existing infrastructure. social vulnerability should be the first concern since it relates to the number of people affected (koroglu et al., 2019; liu et al., 2020; malherbe et al., 2020). the readiness of every resident in the face of disasters significantly affects vulnerability. in case the community is ready to face any disaster, the severity can be reduced. 191 lina wahyuni et al / geosi vol 5 no 2 (2020) 186-195 social vulnerability is the ability to recover from the impact of natural disasters based on age and sex group of the populations (dawyer, 2004. in zulkarnaen, 2012). it is based on the understanding of the disaster and the resulting conditions. this includes the ability to evaluate when it occurs and the recovery process. the population of women, children, and the elderly is considered the most vulnerable (subarkah, 2009). based on the law of the republic of indonesia number 24, 2007 on disaster countermeasure, the vulnerable groups include infants, toddlers, and children of pregnant and lactating mothers, the disabled and the elderly. according to subarkah. (2009), the components used in calculating social vulnerability include age and sex groups. the vulnerability is assessed based on an understanding of current and post-disaster conditions based on the evacuation capability. in this assessment, the population of women, children, and the elderly are targeted. table 2 shows the population in bantul regency, which can be potentially affected in case the tsunami strikes. this data includes the number of people living in the district directly facing the indian ocean. population density also affects the vulnerability of a region. table 2 shows the pandak district has the highest population and density. table 2. population and population density based on district which directly facing the indian ocean in bantul regency district population population density srandakan 29,130 1,590 sanden 30,114 1,300 kretek 30,111 1,125 pundong 32,321 1,365 bambang lipuro 38,206 1,684 pandak 48,950 2,014 source : statistics of bantul regency (2016) economic vulnerability is the risk of damage, negative impact, or external shock resistance due to unexpected events (koroglu et al., 2019; liu et al., 2020). the calculation losses can be a good indicator of the economy (gulllaumom, 1999, in zulkarnain 2012). physical vulnerability is the last aspect describing the extent of damage to physical infrastructures exposed to hazards, such as residential buildings (ishtiaque et al., 2019). it affects the local community's structural readiness and the condition of structures (prasstiya, 192 lina wahyuni et al / geosi vol 5 no 2 (2020) 186-195 2013). the main physical vulnerability in bantul regency include jjls and the existence of airport . the most important thing to do in adjusting the development of risk management strategies is to assess vulnerability to potential tsunami damage in the proper order (lantz et al., 2020). however, vulnerability assessment has never been formulated in an appropriate legal document. building vulnerability means calculating thestructures' capacity in the horizontal pressure of tsunami flows and its susceptibility to water (dall'osso et al., 2009; koroglu et al., 2019). 4. conclusion in this study, the ranking of the element at risk involves social, economic, and physical vulnerabilities. social vulnerability is considered to be the most powerful aspect associated with detailed and varied subcomponents. the economic vulnerability comes second in terms of the economic conditions of a society. it is closely related tocommunities’specific capacity to survive. physical vulnerability is rated last since rebuilding of infrastructures is easier than social or economic development. conflict of interest the authors declare that there is no conflict of interest with any financial, personal, or other relationships with other people or organizations related to the material discussed in the article. references al-faesly, t., palermo, d., nistor, i., and a. cornett, a. (2012). experimental modeling of extreme hydrodynamic forces on structural models. int. j. protect. struct, vol. 3 (4), pp. 477–506. balasundareshwaran, a., kumaraswamy, k., balasubramani, k. (2020). multi-hazard zonation for effective management of disasters in tamil nadu. geosfera indonesia, vol. 5(1), doi: https://doi.org/10.19184/geosi.v5i1.16710. bmkg. (2012). pedoman pelayanan peringatan dini tsunami. inatews. edisi kedua. bnpb. (2012). indeks risiko bencana indonesia. badan nasional penanggulangan bencana. jakarta. https://doi.org/10.19184/geosi.v5i1.16710 193 lina wahyuni et al / geosi vol 5 no 2 (2020) 186-195 chen & cheng. (2016). experimental study of uplift loads due to tsunami bore impact on a wharf model. international journal of coastal engineering, vol. 117 (2016), pp. 126–137. contreras-lopez, m., winckler, p., sepúlveda, i, andaur-álvarez, a, cortés-molina, f., guerrero, c. j., mizobe, c.e., igualt, f., breuer, w., beyá, vergara, h., figueroasterquel, r. (2016). field survey of the 2015 chile tsunami with emphasis on coastal wetland and conservation areas. pure appl. geophys. vol. 173 (2), pp. 349367. dall’osso, f.m., gabbianelli, g., withycombe, g., goff, j., dominey-howes, d.a. (2009). revised (ptva) model for assesing the vulnerability of building to tsunami damage. natural hazard earth science. 9:1557-1565. freire, s., aubrecht, c., wegscheider , s. (2012). advancing tsunami risk assessment by improving spatio-temporal population exposure and evacuation modeling. natural hazards 68:1311-1324. fritz, h.m. (2010). field survey of the 27 february 2010 chile tsunami. pure appl. geophys, vol. 168 (11), pp. 1989–2010. ghobarah, a., saatcioglu, m., nistor, i. (2006). the impact of the 26 december 2004 earthquake and tsunami on structures and infrastructure. eng. struct, vol. 28 (2), pp. 312–326. government regulation number 50. (2011) concerning master plan of national tourism development year 2010 2025. jakarta : president of the republic of indonesia grilli, s.t. (2007). “source constraints and model simulation of the december 26, 2004, indian ocean tsunami”. port coast. ocean eng., vol. 133 (6), pp. 414–428. haipour, v., vafaie, f., kerle, n. (2019). an indicator-based approach to assess social vulnerability of coastal areas to sea-level rise and flooding: a case study of bandar abbas city, iran. ocean & coastal management, vol 188., 105077. ibrahim, h.s., hegazy, i. (2013). decentralization in the egyptian coastal management. journal of coastal zone management, vol 16(2), pp. 102-113. ishtiaque, a., eakin, h., chhetri, n., myint, s.w., dewan, a., kamruzzam, m. (2019). examination of coastal vulnerability framings at multiple levels of governance using spatial mcda approach. ocean & coastal management, vol. 171, pp. 66-79. iverson, l.r., & prasad, a.m. (2007). using landscape analysis to assess and model tsunami damage in aceh province, sumatra. landscape ecol, vol. 22, pp. 323–331. koroglu, a., ranasinghe, r., jimenez, j.a., dastgheib, a. (2019). comparison of coastal vulnerability index applications for barcelona province. ocean & coastal management, vol. 178, 104799. 194 lina wahyuni et al / geosi vol 5 no 2 (2020) 186-195 lantz, t.c., moffat, n.d., jones, b.m., chen, q., tweedie, c.e. (2020). mapping exposure to flooding in three coastal communities on the north slope of alaska using airborne lidar. coastal management, vol. 48(2), pp. 96-117. leonard, l. & lucinda (2014). tsunami hazard assessment of canada. nat hazards, vol. 70, pp. 237–274, 2014. liu, r., pu, l., zhu, m., huang, s., jiang, y. (2020). coastal resource-environmental carrying capacity assessment: a comprehensive and trade-off analysis of the case study in jiangsu coastal zone, eastern china. ocean & coastal management, vol. 186, 105092. liyanage, a.n. & lee, h. (2012). a schematic approach for gis application for tsunami disaster management. asea/drbc, ccis 340, pp. 395-400. marherbe, w., sauer, w., aswani, s. (2020). social capital reduces vulnerability in rural coastal communities of solomon islands. ocean & coastal management, vol. 191, 105186. mardiatno, d. (2008) risiko tsunami di pantai selatan jawa: belajar dari kejadian tsunami di banyuwangi pada tahun 1994 dan di pengandaran pada tahun 2006. jurnal kebencanaan indonesia, vol. 6 (2), pp. 15-32 mcguire, c.j. (2020). coastal resiliency through value capture and transfer: a framework proposal. coastal management, vol. 48(2), pp. 57-76. muta’ali, l. (2014). development planning based on disaster risk reduction, (in bahasa perencanaan pengembangan wilayah berbasis pengurangan risiko bencana). badan penerbit fakultas geografi, universitas gadjah mada, yogyakarta. nandasena, n., sasaki, y., tanaka, n. (2012). “modeling field observations of the 2011 great east japan tsunami: efficacy of artificial and natural structures on tsunami mitigation. coast. eng, vo. 67, pp. 1–13. prasstiya, r.t. (2013). manajemen risiko tsunami di pulau-pulau kecil (gilitrawangan) kecamatan pemenang kabupaten lombok utara. master thesis.universitas gadjah mada, 2013. rangel-buitrago, n., neal, w.j., bonetti, j., anfuso, g., de jonge, v.n. (2020). vulnerability assessments as a tool for the coastal and marine hazards management: an overview. ocean & coastal management, vol. 189, 105134. roshan, a.d., basu, p.c., jangi, r.s. (2016). tsunami hazard assessment of indian coast. nat hazards, vol. 82, pp. 733–762. shibayama, t., esteban, m., nistor, i., takagi,h., thao, n.d., matsumaru, r., mikami, t., aranguiz, r., jayaratne, r., ohira k. (2012). classification of tsunami and evacuation areas. natural hazards 67:365-386. statistic of bantul regency. (2016). bantul dalam angka. bantul: bps. 195 lina wahyuni et al / geosi vol 5 no 2 (2020) 186-195 subarkah. (2009). spatial multi criteria evaluation for tsunamis vulnerability: case study of coastal area parangtritis, yogyakarta, indonesia. master thesis, universitas gadjah mada, yogyakarta. suppasri, a. (2012). damage characteristic and field survey of the 2011 great east japan tsunami in miyagi prefecture. coast. eng. j., vol. 54 (01). tanaka, n. (2008). vegetation bioshields for tsunami mitigation: review of effectiveness, limitations, construction, and sustainable management. landscape ecol eng 5:71-79. tanaka, n., jinadasa, k. b. s. n., mowjood, m.i.m., fasly, m.s.m. (2010). coastal vegetation planting projects for tsunami disaster mitigation: effectiveness evaluation of new establishments. landscape ecol eng 7:127-135. trihatmoko, e. (2017). proses dan dampak dinamika wilayah kepesisiran jawa tengah dan daerah istimewa yogyakarta. master thesis. universitas gadjah mada, yogykarta. yeh, h., sato, s., tajima, y. (2013). the 11 march 2011 east japan earthquake and tsunami: tsunami effects on coastal infrastructure and buildings. pure appl. geophys, vol. 170 (6–8), pp. 1019–1031. zulkarnain, m. w. d.(2012). evaluasi multi-kriteria keruangan untuk penilaian risiko total tsunami di pacitan. master thesis. universitas gadjah mada, yogyakarta. luh sukariasih et al/ geosi vol. 4 no. 2 (2019) 175-187 175 improving the learning outcomes of knowledge and inquiry skill domain of third grade students at smp negeri 14 kendari using guided inquiry learning model assisted by science kit luh sukariasih1*, i gede purwana edi saputra2, fahrudi ahwan ikhsan3, andri estining sejati4, khaerun nisa1 1department of physics education, halu oleo university, indonesia 2department of physics education, sembilanbelas november kolaka university, indonesia 3department of geography education, university of jember, indonesia 4department of geography education, sembilanbelas november kolaka university, indonesia *email: luhsukariasih@yahoo.com received 29 march 2019/ revised 13 august 2019/ accepted 18 august 2019/ published 23 august 2019 abstract the study aims to improve the learning outcomes in the field of knowledge and inquiry skill in class viii 5 smp negeri 14 kendari on the subject matter of light in atmosphere as the effect of applying the guided inquiry learning model assisted by science kit. the method of the study used a classroom action research with research design is cycle model. the research subject is the students of class viii 5 smp negeri 14 kendari in the academic year 2016/2017 which consist of 26 students. the learning data achievements of the learners' realm were obtained through the learning result test (cycle test), the skill data of the learners were obtained through the inquiry sheet, and then was analyzed used the descriptive statistics. results of data analysis are: 1) learning outcomes increased from 60,31 in cycle i to 75 in cycle ii; 2) the students group inquiry skill increased form average value 2.68 (enough category) in the cycle i to 3.15 (good category) in cycle ii; 3) the students mastery learning percentage increase from 42.31% (11 students) in cycle i to 77% (20 students) in cycle ii. it could be concluded that the implementation of guided inquiry learning model assisted by science kit could improve the learning outcomes of knowledge and inquiry skill domain on class viii 5 smp negeri 14 kendari in the subject matter of light in atmosphere. keywords: guided inquiry, inquiry skills, learning outcomes,science kit. 1. introduction education science is a branch of science that is built on observation and classification of data, and is usually compiled and verified in quantitative laws, which involve the application of mathematical reasoning and data analysis to natural phenomena. natural events are included in the study of physical geography. in essence, education science is a science of natural phenomena that is poured in the form of facts, concepts, principles, and laws that are validated and through a series of activities in the scientific method (depdiknas, 2004). according to aksa et al. (2019), geography spesification are physical geography, social geography, and technical geography. geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.4 no. 2 (2019), 175-187, august, 2019 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v4i2.10097 luh sukariasih et al/ geosi vol. 4 no. 2 (2019) 175-187 176 one of physical geography study way through mathematics or counting. this is often feared and tends to be disliked by most students which has an impact on the low level of understanding of teaching material. according to sohibun (2014), learning with a count is still to understanding in the form of conceptsand formulas. the results of preliminary observations made on viii class students in smp negeri 14 kendari on 6th december 2016, found low learning outcomes in the realm of students' knowledge especially in the subject matter of light in atmospherein class viii 5. this can be seen from the average daily test results obtained by the value of 67.3. 13 out of 23 students (57%) scored below the minimum completion criteria (68 points) and only 10 students (43%) completed. the results of interviews with teachers in class viii 5 obtained learning outcomes in the realm of students' knowledge more on factual knowledge, while for conceptual knowledge, procedural knowledge, and metacognitive knowledge were only a few that students could understand. students rarely ask questions in the learning process, meaning that the ability of students to be involved in formulating problems or questions is also lacking. experimental activities in atmosphere light material that lack make competent skills in this case the skills to carry out experiments, collecting observational data and formulating conclusions are also lacking. according to anderson & krathwohl (2015), the knowledge dimension consists of: four types: factual knowledge, conceptual knowledge, procedural knowledge, and metacognitive knowledge. the low average learning outcomes of atmosphere light material according to observation and interviews viii 5 class smp negeri 14 kendari caused in the learning process the model used by the teacher is teacher centered. teacher is very active while the students tend to be passive in the learning process which makes learning monotonous and less student participation. this learning process makes it students difficult to understands the material taught by the teacher. teacher teach less of experiment activities on material that requires experimental activities made students think abstractly about the material. according to sanjaya (2014), in conventional learning the position of students as objects of learning with the role as recipients of information passively. the students are only faced with concepts and formulas without any learning activities that demand the full activity of students in understanding the knowledge taught. the learning process at the junior secondary level is still dominated by teachers compared to students with one-way communication especially in the viii 5 class smp negeri 14 kendari. this is thought to be one of the factors causing low understanding of subject matter for junior high luh sukariasih et al/ geosi vol. 4 no. 2 (2019) 175-187 177 school students. according to amaliana (2017), in teacher-centeder learning, teachers play important roles in the learning process as information providers or evaluator, and students are viewed as learners who passively receive information. the solution about the lack of student learning process and outcome is using leaning model. one of learning model that can make students more active and the learning process more interesting is the guided inquiry. the guided inquiry emphasizes students to be active and find their own knowledge. this relates to conceptual knowledge and procedural knowledge is easier to understand if students can find their own knowledge through experiments. a good learning process is that students are more active than teachers, because the learning process like this is more interesting and the material is easier to understand. according to hidayati et al.(2016), in formulate problems and make hypotheses stages the student become active thinking direcly confronts the issues to be resolved. according to hardianti & kuswanto(2017), learning through inquiry gives learnenrs independence by encouraging them to have a more active and responsible role in various stages of investigation. guided inquiry can improve the inquiry skills and students learning outcome. guided inquiry can more effective if use experimental equipment in the school like science kit tools. there is science kit tools in the science laboratory in smp negeri 14 kendari. based on the analysis of the problem, the teacher obtained the appropriate model to solve the student problem in the class with the guided inquiry learning model assisted by science kit. according to greenwald & quitadamo (2014), inquiry learning model combine with clinical case namely ibcc in the health matter in the neuro anatomy cursus students learn by using process skills, attitudes, and rational thinking knowledges. according to kuhlthau et al.(2015), inquiry directly connects between matter and the real world. many people think that the light in atmosphere material is quite difficult because some of the sub-material makes students think abstractly so that there is needed for direct activity to finding concepts. the use of guided inquiry learning assisted by science kit is very suitable in learning atmosphere light material. guided inquiry learning model is learning that involves all the ability of students to search and investigate systematically and logically so that they can formulate their own findings. guided inquiry learning will be more effective with practical activities in this case utilizing science kit. application of this model is carried out in two cycles of learning in the classroom to improve learning outcomes in the realm of students' knowledge and skills. guided inquiry learning model that is a model that emphasizes more on students to actively train courage, luh sukariasih et al/ geosi vol. 4 no. 2 (2019) 175-187 178 communicate and try to find their own knowledge to solve problems faced through an experiment with direct guidance by the teacher. the combination of inquiry and science kit models is very suitable, because this model will make students find their own knowledge through direct activities of students in this case the experiment using science kit teaching aids. according to piaget (1970), by using real experience, a person's cognitive development will be better than just using language to communicate. according to sapriya (2014), guided inquiry learning has the advantage of developing thinking skills, knowledge, attitudes, and values in students compared to the classical approach. the research by ahmadi (2015) conducted at sdn 1 telaga, gorontalo district showed that learning by using kit teaching aids in science learning can make students more easily understand the material being taught, and students are more enthusiastic in learning learning. based on this description, the purpose of this study is to improve learning outcomes in the realm of knowledge and skills in the form of students ofclassviii 5 of smp 14 kendari in learning the subject matter of light in atmosphere through a guided inquiry guided model science kit. 2. the methods this study used a type of classroom action research. the research was conducted from 10 may to 24 may 2017 in 2016/2017 academic year with the subject matter of light in atmosphere. the subjects of this study were all students on class viii 5 in the even semester of smp negeri 14 kendari with 26 students. the research design is a cycle model. before each cycle phase is carried out first a preliminary study is carried out. the data in this research were analyzed using descriptive statistics. determination of the value of the real learning outcomes of students’ knowledge of the range of scores used for the description test in this study is 0 to 100 with the formula (tim direktorat pembinaan smp, 2017). the average value of learning outcomes in the knowledge class ( ), standard deviation (sd),% complete, and categorizing the value of learning outcomes with formula (sudjana, 2014). normalized gain (n-gain) is an increase in learning outcomes in the realm of students knowledge and skills in the first cycle and second cycle of inquiry are determined using equations from (riduwan, 2015). n-gain criteria ≥ 0.7 (high), 0.3 ≤ n-gain> 0.7 (medium), n-gain <0.3 (low). calculating and classifying the average score of inquirt skills associated with students with formula (sugiyono, 2014).below is reseach flow diagram. luh sukariasih et al/ geosi vol. 4 no. 2 (2019) 175-187 179 figure 1. classroom action research flow diagram (arikunto, 2016) 3. results and discussion 3.1. inquiry skills of student groups the summary of the results of data analysis in the inquiry group skills of students in the teaching-learning process in each cycle can be seen in table 1. table 1. results of data analysis of inquiry skills for student groups per cycle no observed aspects the average value of inquiry skills student groups per cycle n-gain cyclei categories cycle ii categories 1. formulate problems 2,91 satisfactory 3,12 good 0,19 2. formulate a hypothesis 2,25 satisfactory 3 good 0,43 3. experiment 2,67 satisfactory 3,25 good 0,44 4. collecting data 3,08 good 3,37 good 0,32 5. formulating conclusions 2,5 satisfactory 3 good 0,33 the average value of inquiry skills in groups of students 2,68 3,15 0,34 categories satisfactory good medium resources:riduwan (2015), sanjaya (2014), sugiyono (2014) based on table 1, it can be seen that in the first cycle there were four aspects of inquiry skills in groups of students who obtained an average value with satisfactory beginning reflextion planning action observation reflextion cycle 1 planning action observation reflextion cycle 2 luh sukariasih et al/ geosi vol. 4 no. 2 (2019) 175-187 180 categories, namely aspects of formulating problems, aspects of formulating hypotheses, aspects of conducting experiments and aspects of formulating conclusions. this shows that in the first cycle, the skills of the inquiry group of students was not optimal. in the second cycle the skills of inquiry students groups in each aspect had increased. the lowest average value of inquiry group skills of students in the cicle i, that’s mean the aspect of formulating a hypothesis increases in the second cycle to 0.75. while the average value of inquiry skills in the highest students group in the first cycle, that’s mean the aspect of collecting data increased by cycle ii to 0.29. in the second cycle of the 5 aspects of inquiry skills the observed group of students had an average score of 3.15 which good categorized. the average value of inquiry group skills in the first cycle and second cycle can be seen in table 1. from the table, the increase in student inquiry skills is shown by the average n-gain which is categorized as a moderate increase and the average value of inquiry skills group of students experienced an increase of 0.47. 3.2 teacher activity an overview of teacher activities in managing learning using a guided inkuri learning model assisted by science kit, teacher activities in each cycle can be seen in table 2. table2.results of data analysis of teacher activities on each cycle no aspects observed value average cycle i cycle ii a. introduction 1 opening the lessons and check the readiness of students 4 4 2 give apperception to students 3 4 3 deliver/write down topics and learning objectives. 3 3 b. main activity 4 presenting problems so students can formulate problems 4 4 5 direct students to gather information according to what they see at the stage of presenting the problem 3 4 6 direct students to get information through experiments 2,5 3 7 direct students to formulate explanations based on the results of the experiment 2,5 3 8 direct students to analyze experimental data in the form of conclusions 3 4 c. post activity 9 conclusion on the results of the activity 2,5 4 10 the teacher informs the material for the next meeting 3 3 d. class atmosfer 11 enthusiastic students 2,5 3 12 enthusiastic teacher 3 3 13 time according to allocation 3 4 14 kbm according to rpp 2,5 3 average value 2,9 3,5 category enough good luh sukariasih et al/ geosi vol. 4 no. 2 (2019) 175-187 181 resousces: sanjaya (2014), sugiyono (2014) based on table 2 it can be seen that in the first cycle the average value of the teacher' lowest activity was the activity of the teacher directing students to obtain information through experiments, directing students to formulate explanations based on the results of the experiment and the conclusion of the results of the activity. while the highest teacher activity in the first cycle was when opening lessons and checking the readiness of students and presenting problems so that students can formulate problems. in the second cycle, it was seen that every aspect observed was maintained and experienced an increase. one aspect of teacher activity with the lowest average value in cycle i is that the teacher directs students to obtain information through experiments increasing in the second cycle of 0.5. in addition, the lowest average value of other teacher activities in the first cycle is the conclusion of the results of increased activities in the second cycle of 1.5. table 2, shows an increase in teacher activity from cycle i to cycle ii where the average value of teacher activity has increased by 0.6. 3.3 learning outcomes of students knowledge data on the realm learning outcomes of students' knowledge is obtained by using learning outcomes tests. based on the descriptive analysis of the learning outcomes of the realm of students 'knowledge on the subject matter of atmosphere light shown in the form of cycle tests consisting of cycle i tests and cycle ii tests, a summary of the results of data analysis of the learning outcomes of students' knowledge per cycle is as follows. table 3.learning outcomes data analysis results of student knowledge sphere per cycle no. value cycle n-gain i ii 1 minimum 20 22 -0,272 2 maximum 78 95 0,785 3 average 60,31 75 0,345 4 deviation standard 17,26 14 0,254 amount of completion 11 20 amount of incomplete 15 6 % complete 42,31 77 % incomplee 57,69 23 resources: riduwan ( 2015), sudjana (2014) tim direktorat pembinaan smp (2017) from table 3 above, it can be seen that the knowledge learning outcomes of viii5 students of smp negeri 14 kendari on the subject matter of atmosphere light learning luh sukariasih et al/ geosi vol. 4 no. 2 (2019) 175-187 182 through the application of a guided inquiry learning model assisted by science kit indicate an increase from cycle i to cycle ii. this is seen in the value of the average learning outcomes in the realm of knowledge increasing from cycle i to cycle ii, it can be seen from the average n-gain of 0.345 in the medium category. the percentage of learning completeness from cycle i increased to cycle ii to be above 75% who had achieved kkm, showing completeness classically from classroom action research has been fulfilled which means that the model of guided inquiry teaching assisted by science kit can solve learning problems of viii5 students in smp negeri 14 kendari. 3.4 cycle i the results showed that in the first cycle there were still some aspects of the skills of the inquiry group of students that needed to be improved. the skills of inquiry groups of students who are still lacking and need to be improved are in the aspects of formulating problems, formulating hypotheses, conducting experiments and formulating conclusions. this is because students are not used to formulating problems, formulating hypotheses and formulating conclusions with learning models with the help of applied science kit. the low average value of group inquiry skills is influenced also by the teacher who still lacks directing students in conducting experiments and formulating conclusions during the learning process. the average value of the problem formulation is higher than the average value of the aspects of formulating the hypothesis, this is due to students' initial knowledge of the concepts related to the material in presenting problems that are still lacking so that students have difficulty when formulating hypotheses. according to hidayati et al. (2017), teachers should be able to prepare the questions about the problem problem is close to student environment. in the first cycle based on descriptive analysis, the teacher's activity shows the average value of teacher activity in a sufficient category. where teacher activity is still quite based on. table 2 of which is the teacher is still lacking in directing students to obtain information through experiments, directing students to formulate explanations based on the results of the experiment and formulating conclusions on the results of the activities. based on the results of reflection on teacher activity, by knowing the shortcomings in the first cycle, the teacher improved the way to teach learning material in accordance with the guided inquiry learning model assisted by science kit, so that it was expected that in the next meeting an increase in teacher activity. according to sitorus et al. (2017), in guided learning teacher can manage and implement a learning to students which contains scientific steps. luh sukariasih et al/ geosi vol. 4 no. 2 (2019) 175-187 183 based on the first problem, namely how to improve the learning outcomes of knowledge in class viii5 smp negeri 14 kendari as the effect of applying a guided inquiry learning model assisted by science kit on the subject matter of light in atmosphere, it can be explained that based on the results of descriptive analysis of learning outcomes in the knowledge domain each cycle tends to increase towards the better. according to zaini (2016), there is a significant effect that is given by using guided inquiry based learning with the cognitive process learning outcome. the percentage of completeness in this first cycle has not yet reached the research target, which is to achieve learning completeness in a classical minimum of 75%. this is because students have not been able to recall the material being taught, besides that students pay less attention and listen to the initial problems conveyed by the teacher, students are not accustomed to formulating conclusions, and during the experiment the students are less cooperative with their group friends. in addition, the teacher is not optimal in delivering direction and guidance to students in conducting experiments and formulating explanations in the form of conclusions so that students experience obstacles to conducting experiments and formulating conclusions on the results of experiments. according to wardani et al. (2015), cooperation can be increased through guided inquiry learning. after analyzing and reflecting on the first cycle, the teacher in this case the researcher and observer make improvements in learning through guided inquiry learning assisted by science kit to be applied in the second cycle, so that the realm of learning outcomes of knowledge of viii5 students in smp negeri 14 kendari can increase as expected in cycle ii. 3.5 cycle ii from the results of the descriptive analysis of the skills of inquiry groups of students in the second cycle showed an increase in the skills of inquiry groups of students from cycle i. this is as shown in table 1, the average skill scores of groups in the second cycle were 3.15 by category well. the skills aspect of inquiry groups in the second cycle on average experienced an increase from the first cycle. improving the skills of the best group inquiry inquiry was on the aspect of formulating a hypothesis, where the aspect of formulating this hypothesis increased by 0.75 higher than the increase in other aspects of inquiry skills. . this is because students are getting used to formulating hypotheses, assisted by teachers with clearer direction and presenting clearer problems also in the learning process using a guided inquiry learning model assisted by science kit. according to sarwi&prayitno (2016), there is luh sukariasih et al/ geosi vol. 4 no. 2 (2019) 175-187 184 a significant application of guided learning model to the students inquiry 'understanding of the concept and being able to improve practice in inquiry syntax. the inquiry process is characterized by the presentation of problems that can be solved in groups through experiments that develop ideas and thoughts and activities centered on problem solving skills. in this learning model students make questions that guide the next investigation, including activities to form hypotheses, carry out experiments, collect experimental data, and formulate conclusions experiments. the teacher acts as a facilitator. the increase in the average value of the inquiry group skills indicates that the weaknesses or weaknesses found in the first cycle can be overcome so that the skills of the inquiry group of students are obtained as expected. according to putra et al. (2016) the application of guided inquiry trains students to pass the learning syntax well and is able to improve students science literary skills. in the second cycle the teaching activity of the teacher showed a significant increase, where in the second cycle the average value of the teacher's activity obtained an average value of 3.5 which was categorized as good. the results of the analysis and observations in the second cycle showed an increase in teacher activity by implementing a guided inquiry learning model assisted by science kit. increasing the average value of teacher activity indicates that the weaknesses contained in the first cycle can be overcome so that the teacher can manage learning using a guided inquiry learning model assisted by science kit. according to niana et al.(2016), the teacher's activities in applying the guided inquiry model were able to improve student learning success. from the results of descriptive analysis of the learning outcomes of the realm of students' knowledge shows an increase in learning outcomes in the realm of knowledge from cycle i to cycle ii. this can be seen with the average value obtained by students in the first cycle increased in the second cycle. improving the learning outcomes of the students 'knowledge in the second cycle showed an increase in students' mastery of learning material and the motivation of students to attend learning until the last meeting. according to mulyana et al. (2018), there is a significant influence guided inquiry learning the student learning result. the increase in learning outcomes is also because the teacher has been able to manage the learning process, besides that students are also familiar with the guided inqury learning model assisted by science kit in the learning process, because in the guided inquiry learning model assisted by science kit students can observe directly the concepts that are taught by conducting experiments and can be more creative looking for answers to the problems given. luh sukariasih et al/ geosi vol. 4 no. 2 (2019) 175-187 185 so that students are not difficult to understand the concept of science, especially in the subject matter of atmosphere light and relate it to their experience in everyday life. according to yewang et al. (2016) guided inquiry is better than free inquiry in guiding students in investigations, observations and hypothesestests. 4. conclusion the conclusion in this study is the application of a guided inquiry learning model assisted by science kit can improve learning outcomes in the aspect of knowledge, skills and learning completeness of students of class viii 5 of smp negeri 14 kendari on the subject matter of atmosphere light. this conclusion is supported by several specific conclusions of the results of descriptive empirical data analysis as follows. a. the skills of inquiry in groups of viii 5 students in smp negeri 14 kendari through the assisted guided inquiry learning model of kit ipa have increased. this can be seen from the average value of the skills aspects of the inquiry group of students in the first cycle and second cycle. where in the first cycle obtained an average value of 2.68 sufficient categories, increased in the second cycle to 3.15 good categories. b. the realm of learning outcomes of knowledge of grade viii 5 students of smp negeri 14 kendari who learned through assisted guided inquiry learning model kit ipa increased from the first cycle to the second cycle which was indicated by the average value of the realm learning outcomes of students' knowledge increased from 60.31 to 75, the standard deviation decreased from 17.26 to 14 and the average n-gain was 0.34 medium category. c. the learning completeness of grade viii 5 students of smp negeri 14 kendari who learned through a guided inquiry learning model assisted by science kit showed that there was an increase in the percentage of learning completeness from cycle i to cycle ii, in the first cycle the completeness percentage was 42.31% or 11 students had reached minimum completeness criteriaand in cycle ii the percentage of completeness increased to 77% or 20 students had reached. references ahmadi, l. (2015). pemanfaatan alat kit pada pembelajaran.gorontalo: universitas negeri gorontalo. aksa, f.i., utaya, s., & bachri, s. (2019). geografi dalam perspektif filsafat ilmu. majalah geografi indonesia,33(1), 43-37. luh sukariasih et al/ geosi vol. 4 no. 2 (2019) 175-187 186 amaliana, i. (2017). teacher-centered or student-centered learning approach to promote learning?. jurnal sosial humaniora, 10(2), 59-70. anderson, l.w., & krathwohl, d.r. (2015). kerangka landasan untuk pembelajaran, pengajaran, dan asesmen revisi taksonomi pendidikan bloom (a. priantoro, trans.). yogyakarta: pustaka pelajar. arikunto, s. (2016). prosedur penelitian suatu pendekatan praktik. jakarta: rineka cipta. depdiknas. (2004). kurikulum mata pelajaransains smp danmts.jakarta: depdiknas. greenwald, r.r.,&quitadamo, i.j. (2014). a mind of their own: using inquiry-based teaching to build critical thinking skills and intellectual engagement in an undergraduate neuroanatomy course. the journal of undergraduate neuroscience education, 12(2), 100-106. hardianti, t., & kuswanto, h. (2017). difference among levels of inquiry: process skills improvement at senior high school in indonesia. international journal of instruction, 10(2), 119-130. hidayati, d.n., amaluddin, l.o., & surdin. (2016). the effect guided inquiry to critical thinking ability to build student character in geography subject. social science, education and humanities research,9(1), 367-371. kuhlthau, c.c., maniotes, l.k., & caspari, a.k. (2015). guided inquiry: learning in the 21st century(2nd ed.). california: libraries unlimeted. mulyana, s., rusdi, & vivanti, d. (2018). the effect of guided inquiry learning model and scientific performance on student learning outcome. indonesian journal of science and education, 2(1), 105-109. niana, r., sarwanto, & ekawati, e.y. (2016). the application of guided inquiry model on physic learning to improve scientific attitude and students analysis ability. proceedings of the 2nd international conference on teacher training and education sebelas maret university,2(1), 605-615. piaget, j. (1970). science of education and the psychology of the child. new york: wiley. putra, m.i.s., widodo, w., & jatmiko, b. (2016). the development of guided inquiry science learning materials to improve science literacy skill of prospective mi teachers.jpii, 5(1), 83-93. riduwan. (2015). dasar-dasar statistika. bandung: tarsito. sanjaya, w. (2014). strategi pembelajaran. jakarta: kencana prenada media group. sapriya. (2014). pendidikan ips. bandung: remajarosdakarya. sarwi, s.,& prayitno, w.w. (2016). implementation of guided inquiry physics instruction to increase an understanding concept and to develop the students character conservation. jurnalpendidikanfisika indonesia,12(1), 1-7. luh sukariasih et al/ geosi vol. 4 no. 2 (2019) 175-187 187 sitorus, h.h., hasruddin, & edi, s. (2017). the influence of inquiry learning model on student’s scientific attitudes in ecosystem topic at mts. daarul hikmah sei alim (islamic junior high school) asahan. international journal of humanities social sciences and education (ijhsse), 4(11), 170-175. sohibun. (2014). penerapan strategi belajar dengar lihat kerjakan (delikan) berbasis laboratorium mini terhadap ketrampilan proses sains (kps) siswa sma kelas x mia. jurnal imliah edu research, 3(1), 53-67. sudjana, n. (2014). penelitian hasil proses belajar mengajar. bandung: remaja rosdakarya. sugiyono. (2014). metode penelitian pendidikan pendekatan kuantitatif, kualitatif, dan r&d. bandung: alfabeta. tim direktorat pembinaan smp. (2017). panduan penilaian oleh pendidik dan satuan pendidikan sekolah menengah pertama. jakarta: kementerian pendidikan dan kebudayaan direktorat jenderal pendidikan dasar dan menengah direktorat pembinaan sekolah menengah pertama. wardani, s., nurhayati, s., & safitri, a. (2015). the effectiveness of the guided inquiry learning module towards students’ character and concept understanding. international journal of science and research (ijsr), 5(6), 1589-1594. yewang, m.u.k., degeng, i.n.s., setyosari, p., & sulton. (2016). the effect of guided inquiry learning method vs free inquiry against learning outcomes. international conference on educationum, 561-568. zaini, m. (2016). guided inquiry based learning on the concept of ecosystem toward learning outcomes and critical thinking skills of high school student. iosr journal of research & method in education (iosr-jrme), 6(6), 50-55. foreword 65 multi-hazard zonation for effective management of disasters in tamil nadu a. balasundareshwaran1, k. kumaraswamy 2 and k. balasubramani 1* 1 department of geography, central university of tamil nadu, thiruvarur, tamil nadu 610005, india 2 department of geography, bharathidasan university, tiruchirappalli, tamil nadu 620024, india *corresponding author: geobalas@cutn.ac.id received 6 february 2020/ revised 16 february 2020/ accepted 1 march 2020/ published 10 april 2020 abstract natural hazards are a long existing threat to human and their surroundings which may occur throughout the world. tamil nadu is one of the indian states with a number of natural hazard incidences. the occurrence of natural hazards, such as cyclone, storm surge, flood, drought, landslide, forest fire etc., has increased manifold in the recent decades.the multi-hazard zonation is one of the preliminary studies in disaster management scenario, which is used to understand the product of all prominent natural hazards. at the state level, it is imperative for the government to know the regions affected by multiple hazards to help them prepare the management plans appropriately to protect the local communities and infrastructures. however, such systematic hazard assessment and integration in an administrative unit is largely missing in tamil nadu. further, t he utilisation of geoinformatics in the preparation of multi-hazard zonation helps to identify the most endangered areas of the state precisely and offers insights to detailed studies in highly risk zones. this paper attempts on these lines to prepare multi hazard zones (mhz) based on natural hazards viz. earthquake, landslide, cyclone, storm surge, flood, drought and forest fire of tamil nadu. the data for the study were generated from multiple sources, which were all generalised and integrated in a normalised scale. the occurrences, intensities and frequencies of hazards, namely seismic, landslide, and forest fire are the reasons for a very high multi-hazard in hilly tracts of the nilgiris and parts of shayadhri hills in coimbatore and theni districts, whereas cyclone, storm surge, and flood caused a very high risk along the coastal stretch of chennai, kancheepuram, cuddalore and ramanathapuram districts. the segregation of the results into administrative division’s which was then categorised in an order of high risk zones may provide a powerful tool to the state authorities to allocate fund and resources. the output of this study also offers zonation for immediate knowledge, policy briefs, and proper disaster management plan at state level. keywords : disaster management; natural hazards; geoinformatics; tamil nadu 1. introduction according to the disaster statistics from undp’s disaster risk reduction programme (2012), the average disasters per year have increased for more than 60 per cent in the last decade. geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.5 no. 1 (2020), 65-79, april, 2020 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v5i1.16710 accredited by the ministry of research , technology , and higher education of the republic of indonesia, no. 30/e/kpt/2019. 65 mailto:geobalas@cutn.ac.id https://jurnal.unej.ac.id/index.php/geosi https://drive.google.com/file/d/1rsnvas6cuhowhl5bj87cl2l6k5dqz7s6/view a. balasundareshwaran et al / geosi vol 5 no 1 (2020) 65-79 asia has the highest number of victims due to natural disasters. it is not peculiar at all that the increase in the frequency of disaster, its magnitude, complexity, economic impact and number of deaths, registers in the low human development region and less prepared communities. according to the ndma (2016), hazards pose threats to people and assume serious proportions in the under developed countries with dense population. the regional study of hazards helps us understand the influencing factors, analysing them without exclusion of nearby quantifiable factors, provides applicable regional alike solutions. there is a coarse approach followed in disaster plans at state and local level in india where national level zonation considered for all kinds of disaster risk management without detailed regional or local attempts. tamil nadu, the southern-most state of india, nestles in the indian peninsula between the bay of bengal in the east, the indian ocean in the south, and the western ghats and the arabian sea on the west. in the north and west, the state adjoins karnataka, andhra pradesh, and kerala (figure 1). the eastern extremity of the state is point calimere situated at 80°20’ e longitude, while the western tip is the mudumalai sanctuary at 71°15’ e longitude. the northern and southern extremities are defined by pulicat lake (13°35’ n latitude) and cape comorin in kanyakumari (08°50’ n latitude). an effective disaster management program always requires a detailed hazard zone, which is largely omitted in the state. at the same time, natural hazards that rattle the vulnerable communities of tamil nadu are increasing manifold and often occur simultaneously. the natural hazards of tamil nadu occur mostly isolated with seasonal characteristics and seldom occured all together that poseda maximum threat in a combined form within the same region. drought is considered one of the reoccurring disasters of tamil nadu, which hampers the development of the region. even though drought is non-structural, it spreads over a larger geographical area and posesmore serious threats to population than the resultsof other natural hazards such as floods, tropical storms, and earthquakes (balasubramani, 2014). balasundareshwaran, et al., (2019a) evaluate drought within an administrative unit and suggested that, the drought restricts the growth of a region. similarly debated that, flood both gains and losses, where it either sweeps the entire regions or deposits minerals for next seasonal irrigation. likewise, cyclones bring in gusty winds to the coastal parts of tamil nadu, especially during the north-east monsoon season (october-december), which influence the sea level to swell and cause coastal inundation, storm surge, and flooding in the inland rivers where the impacts are multi-fold (ramkumar, 2009). a spatio-temporal pattern of earthquake occurrences in south india was epitomised by gangai et al., (2009) who revealed that seventy-seven occurrences of earthquakes with magnitude above 3.0 were recorded within and adjoined regions of tamil nadu in the last two centuries. ramkumar (2019) argues that the net effects of tectonic quiescent regions and 66 a. balasundareshwaran et al / geosi vol 5 no 1 (2020) 65-79 geomorphometric processes induce the earthquake occurrences in tamil nadu. natarajan, et al.,. (1988) studied the landslides of the nilgiri regionand described that the deforestation had resulted into massive soil erosion along the slopes, which increased the seepage and ,thereby, resulted into an increase in pore pressure leading to landslides in many hilly topography of the state. further, forest fire (wildfires) also increases the air pollutants and the instantaneous concentration of particulate matters in the atmosphere during the fires and poses serious health risks (sofowote & dempsey, 2015). geoinformatics aids in identification, demarcation, assessment, and management of hazards. nowadays, geoinformatics plays a key role in extracting potential information from an extensive region or inaccessible location. satellite remote sensing has successfully proven itself as a valuable information generator for various hazards studies (bhanumurthy et al., 2010). almost all of the natural hazards that can be studied are mapped with the help of geoinformatics. many studies proved that the utilisation of geoinformatics increases the value of datasets as highly reliable, accurate, and cost effective. many attempts, including behanzin et al., (2015), roy and blaschke (2015); shankar et al., (2015); udo (2015); udani & mathur (2016); prasad & narayanan (2016); hoque (2017); oluwasegun (2017); chigbu et al., (2018); sharma et al., (2018), help us to understand the hazard scenario of the state. however, the integration of multi-hazards and delineation of accurate zones using geoinformatics is still missing in tamil nadu. even though arguably the hazard hotspot regions covers the coastal and urban regions (shrinarayan, 2015; balasundareshwaran et al., 2019), mhz covering the entire state with reliable datasets is still scarce. hence, the present study attempted to identify the multi-hazard prone zones of tamil nadu and showcase the use of geoinformatics in a systematic hazard assessment. 2. methods the research primarily deals with the use of geoinformatics in mhz for tamil nadu. in the initial phase, the spatial and temporal dimensions of natural hazards of tamil nadu were examined. all the possible natural hazards were considered and ranked according to the occurrence and impacts in the past, namely drought, flood, cyclone, storm surge, earthquake, landslides, and forest fire. 67 a. balasundareshwaran et al / geosi vol 5 no 1 (2020) 65-79 figure 1. location and study area of tamil nadu the drought datasets used for the study, mainly comprised of three categories (1) meteorological records acquired from ground stations, (2) products derived from the satellite sensors, and (3) ancillary data from various sources. high temporal satellite datasets considering vegetation, temperature, and precipitation were used to compute proxies for drought hazard assessment viz. precipitation condition index (pci), temperature condition index (tci) and vegetation condition index (vci). terra modis surface reflectance mod13q1 (250m) (20002016) used for vci, modis lst of mod11a2 (1km) (2000-2016) was for tci and trmm 3b43 (0.25ο×0.25ο) precipitation estimate (2000-2016) was used for pci. finally, the scaled drought condition index (sdci) a multi-sensor drought index proposed by rhee et al. (2010) was used to calculate composed drought index as given in the equation: vcipcitcisdci 25.05.025.0  (1) the low values of sdci imply serious condition of drought. under a drought process, the sdci is close or equal to 0 and at wet conditions the sdci is close to 1. 68 a. balasundareshwaran et al / geosi vol 5 no 1 (2020) 65-79 the cyclone hazard was assessed by utilising the geographic information system (gis) through a long-term best tracks cyclone database from indian meteorological department (imd) and joint typhoon waring center (jtwc) of bay of bengal for the period of 127 years from 1891 to 2018. storm surge computed by imd based on 50-year return data was adopted for the preparation of storm surge hazard layer. both the layers were compared with the building material and technology promotion council’s (bmptc) vulnerability atlas of india (2006) for conformity and classification. the flood hazard, compared to other hazards,was very difficult to compute on a wider geographical scale, thus it was extracted from the bhuvan geoportal where tile wise flood vulnerability index was computed based on multiple origin of floods (riverine, coastal, urban, flash flood and cyclonic floods). the spatio-temporal characteristic of seismic activities was studied using the data sources of united states geological survey (usgs), coastal geodetic survey (cgs), amateur seismic centre (asc) and imd for tamil nadu and its surrounding regions from 1807 to 2018. based on these datasets and bmptc vulnerability atlas of india, the earthquake zones were delineated. reported landslides and bmptc atlas were used to classify the landslides zones. forest fire hazard map was prepared from the data extracted from tamil nadu forest department and modis satellite data. all the generated hazard layers (earthquake, landslide, cyclone, storm surge, flood, drought, and forest fire) were reclassified into four levels of hazard,namely high, moderate, low, and nonhazard with a cell size of 250 m. by utilising raster calculator tool in arcgis, all the hazard layers were intersected on a normalised scale and multi hazard zones were prepared. based on the combined intensity values, the multi hazard zones were classified into four classes, namely very high, high, moderate, and low. 3. results and discussion 3.1 earthquake the spatio-temporal characteristic of seismic activities in tamil nadu shows concentration around coimbatore, madurai, hosur, salem, shevaroy, villupuram, pondicherry, chennai and dharmapuri (figure 2). the magnitude of the past earthquakes in the study area ranged from 3 to 6. it was observed that the earthquakes of maximum intensity 5-6 had occurred in the coimbatore and surrounding districts. also,it was seen that the areas of maximum seismicity were also the ones that are densely populated. whereas, in spite of the sparse distribution of seismic locations in central and western parts, the frequency tendedto be greater along with magnitude in the western parts in comparison to the central part of the region. 3.2 drought the scaled drought condition index (sdci) is categorised into extreme drought (<0.2), severe drought (0.2-0.3), moderate drought (0.3-0.4), abnormal dry (0.4-0.5), and no drought (>0.5). during the dry year (2016), about half of the state was witnessed the extreme drought. severe drought (0.2 to 0.3) condition was observed in about 30 percent of the state. in 2016, the state was badly hit by the worst annual rainfall in 140 years as it received just 543 mm of rain against the annual average of 920 mm. a weak la-nina over the equatorial pacific that followed a year of 69 a. balasundareshwaran et al / geosi vol 5 no 1 (2020) 65-79 strong el-nino was cited as one of the reasons for this drought. by considering drought condition during june to december in dry year (2016) and normalcy in base year (2007), the sdci drought index was prepared as shown in figure 3. the interior northern district of tamil nadu, such as karur, nammakal, salem, dindigul and erode faced acute drought. figure 2. earthquake zones in tamil nadu figure 3. scaled drought condition index for tamil nadu 70 a. balasundareshwaran et al / geosi vol 5 no 1 (2020) 65-79 z 3.3 cyclone and storm surge the cyclone affecting tamil nadu are largely from bay of bengal. the very high hazard appeared in the northern coastal region of tamil nadu. the moderate zone was observed in central part of tamil nadu, extending as tongue from cauvery delta. the november cyclones generally move west or north-westward and strike northern coasts of tamil nadu (siddiki et al., 2012). the storm surge is often accompanied with the cyclone or sometimes with high wind, which affects the coastal margins, that vary up to 5 km from the coast (figure 5). the hazard map shows a very high figure 4.cyclone zones in tamil nadu figure 5. storm surge in coastal parts of tamil nadu 71 a. balasundareshwaran et al / geosi vol 5 no 1 (2020) 65-79 storm surge (> 4.5 m) in ramanathapuram district’s coast. a high storm surge (3.5 4.5 m) was observed around pulicat lake (northern tamil nadu) which is understood for its tidal activities. 3.4 landslide the western and eastern ghats of the state are prone to landslides. the severe up to very high class was observed in the steep slopes of the western ghats and very confined to the nilgiris, anamalai, kodaikanal, courtallam and agasthyamalai hills. eastern ghat sections, especially shayadri hills and kolli hills,fell under high to moderate landslide hazard (figure 6). 3.5 flood the flood hazard layer shows a combined effect of all flood events of tamil nadu that devastated settlements as well as vegetation. flood vulnerability index for the whole tamil nadu is categorised into five classes, namely very high, high, moderate, low, and very low hazard zones (figure 7). the flood vulnerability zone followed the deltaic regions of majorrivers of tamil nadu, especially between palar to cauvery deltaic region. the upper reaches of tributaries of cauvery and tamirabharani rivers were also found with very high hazard zones. 3.6 forest fire the forest fire is highly concentrated in the western and eastern ghats of the state where forest cover is intersected with settlements and transport lines (figure 8). the forest fire occurred between 2006 and 2015 are classified into five classes of frequency; very low (<4), low (5-9), moderate (10-14), high (15-19), and very high (>20). the very high forest fire occurrences were at mudumalai and gundri in the east kalvarayan, jawathu, kanamangalam, and villapakkam in the west and northern parts of tamil nadu. a cluster of forest fires was observed at valpari, anamalai, palani, kodaikanal, and agamalai hills at eastern central margins of tamil nadu and southern dense vegetation in agasthyamalai hills. 3.7 multi-hazard zonation multi-hazard zones reflect the complex nature of interaction between the hazards. it is very difficult to quantify the interaction but it can be relatively compared (kappes et al., 2012). the natural hazards occur in the same location at different interval cause more damage than the location affected by a single hazard. the multi-hazard zones (mhz) sometimes are found with a domino effect, where one hazard triggers the next possible hazard, which is extremely dangerous. hence, the assessment of mhz is indispensable for disaster risk management and governance of critical time. based on the interaction of all major natural hazards, mhzare delimited and classified into four classes, namely very high, high, moderate, and low (figure 9). the very high mhz is concentrated at hilly stretches of the nilgiris and parts of shayadhri hills in coimbatore and theni districts. further, the very high mhz is found along the coastal stretch of chennai, kancheepuram, cuddalore, and ramanathapuram districts. 72 a. balasundareshwaran et al / geosi vol 5 no 1 (2020) 65-79 figure 6. landslides in western and eastern and ghats of tamil nadu figure 7. tiled flood index figure 8. forest fire hazard in tamil nadu 73 a. balasundareshwaran et al / geosi vol 5 no 1 (2020) 65-79 figure 9. multi-hazard zonation (mhz) for tamil nadu 74 a. balasundareshwaran et al / geosi vol 5 no 1 (2020) 65-79 the high mhz is observed in the central regions of the state engulfing rest of the nilgiris, villupuram, thiruvanamalai, vellore and karur districts, and all along the central and northern coastal tracts of tamil nadu. the occurrences, intensities and frequencies of hazards, namely seismic, landslide and forest fire are the reasons for very high multi-hazard in the hilly tracts, whereas cyclone, storm surge and flood is the major reason for a very high risk along the coastal regions. the moderate mhz vastly spreads over the rest of the state except for a few parts in the northern, eastern, and southern region where hazards with high intensities are absent. the moderate mhz is the direct cause of higher intense of drought but moderate or low intense of cyclone and earthquake hazards. the very high-to-high mhz occurs in the western regions of hilly terrains, central plains, and the eastern margins of coastal regions. the result of this study coincides with case studies attempted for different parts of the state. for instance, agricultural drought assessment in palar basin (krishna et al., 2009) and drought condition over the cauvery basin (balasubramani, 2014) indicate similar prevalence of high mhz at central and northeastern part of the state. the southern part of the nilgirs falls under high and very high vulnerability as the area is under steep slope (rahaman & aruchamy, 2017). moreover, the fire risk assessment at kurangani of theni district forest debated by balaguru et al., (2018) propose that the highly vulnerable zones falls at steep slopes and high altitude regions. comparatively, a study on macrozonation of seismic hazard pursued by menon et al., (2009) exhibits moderate vulnerability in northern and western parts of tn and much lower in the southern half of the state. the study also suggest that the hazard in the northwestern parts, some central districts of the state are clearly underestimated i.e., the hazard levels classified in seismic indian standard zone iii could be marginally higher, especially for chennai, coimbatore, udhagamandalam, and krishnagiri. these discussions support the very highto-high mhz of western regions of hilly terrains and central plains of state. similarly, the study on habitat risk assessment for coastal taluks of tamil nadu (balasundareshwaran et al., 2019) reflects on the assessment of coastal vulnerability utilising the geospatial technology. the study implies the need of urgent measures to thwart negative impacts at chennai, cuddalore, nagapattinam, thoothukudi, and agatheeswaram areas, which are highly vulnerable zones. in the same way, the disaster risk management plan for karur district attempted by balasundareshwaran et al., (2019a) reveals that, during northeast monsoon, heavy water flowing in cauvery and its tributaries, has affected the low-lying areas of the riverbanks with floods. the results of this present study show all the flood occurrences attributed to larger basins of cauvery 75 a. balasundareshwaran et al / geosi vol 5 no 1 (2020) 65-79 and palar rivers. in an integrated study, classifying coastal tamil nadu (rajan et al. 2019) reveals that the very high vulnerability zone covers nagapattinam coast. further, very high to high vulnerable zones cascade over cuddalore, kancheepuram pondicherry, karaikkal, nagapattinam, and thiruvarur. the physical vulnerability analysis conducted by rajan and vengadasalam (2019) along the coastal tamil nadu observed that coastal zone is still in underdeveloped condition. the study proposed that the ramanathapuram district appears to be a better coast and kancheepuram as a poor. consequently, these deliberations correspond and represent the very high-to-high mhz senario of coastal regions. the major research gap exists in developing appropriate approaches to evolve disaster plans for the administrative units like districts. the hazards demarcated at the state level will be effective for planning at district and sub-district level planning and, thus, this study can be used as a pioneer material. the best use of geoinformatics in the digital era, especially in disaster scenarios, is very much needed, and the present work attempts to fulfil this gap. 4. conclusion this study is akin to a first-hand atlas to the planners and decision makers. the study combined different hazards and their intensities in a single map with varying intensities using the power of geoinformatics. these research highlights need for immediate and proper action plans at high multi-hazard prone zones. the very high mhz is observed at the nilgiris and parts of shayadhri hills in coimbatore and theni districts in the western region and along the coastal stretch of chennai, kancheepuram, cuddalore, and ramanathapuram districts in eastern region of tamil nadu. the following recommendations are suggested for the very high -high mhz of natural disasters of tamil nadu: (1) identification and maintenance of the location specific disaster trigger based response system need to be given a higher priority, especially in the eastern hilly terrains and central plains; (2) preparing region specific disaster management plans along with training for professionals / technical institutions to minimise the ill-effects for both administrative and natural regions, especially for the eastern coastal margins. this study offers scope for immediate knowledge, effective regionalisation, and possibilities of preparing disaster management plans. the segregation of results into administrative division’s categorised in an order of highly risk zones will provide a power tool to the state authorities to allocate fund and resources. the further improvement of accuracy of certain datasets, e.g. flood, could precise the zonation and provide robust tool to prepare long-term plans for safeguarding the vulnerable communities, mitigating the physio-socio-economic losses, and attaining sustainable development 76 a. balasundareshwaran et al / geosi vol 5 no 1 (2020) 65-79 conflict of interest the authors declare that there is no conflict of interest with any financial, personal, or other relationships with other people or organizations related to the material discussed in the article. acknowledgement the authors thank the council of scientific and industrial research university grant commission (csir-ugc) and indian council of social science research (icssr) for the financial support to complete the study. the authors also thank ugc-sap-drs-ii programme of the department of geography, bharathidasan university, tiruchirappalli for the infrastructural and technical supports. references balaguru, m., navammuniyammal, m., vidhya, r. and sathyavathi, g., (2018). assessing forest fire prone area in kurangani, tamil nadu using remote sensing and gis. international journal of applied engineering research, 13(7), pp. 264-269 balasubramani, k., (2014). “assessing vegetative drought from satellite data: a case study of cauvery basin, south india”. the konkan geographer, 8, pp.12-18. balasundareshwaran, a., abdul rahaman, s., balasubramani, k., kumaraswamy, k. and ramkumar, m., (2019). “habitat risk assessment along coastal tamil nadu”, india an integrated methodology for mitigating coastal hazards”. coastal zone management, pp. 515-542. doi.org/10.1016/b978-0-12-814350-6.00023-9 balasundareshwaran, a., kumaraswamy, k., balasubramani, k. and abdul rahaman, s. (2019a). “geoinformatics catalyst for preparation of district disaster risk management plan: a case of karur district, tamil nadu”, indian geographical journal, 94 (1), pp. 1-14. behanzin, i.d., thiel, m., szarzynski, j., and boko, m., (2015). “gis-based mapping of flood vulnerability and risk in the benin niger river valley”. international journal of geomatics and geosciences, 6 (3), pp. 16531668. bhanumurthy, v., manjusree, p., and srinivasa rao, g., (2010). “flood disaster management”. remote sensing applications, pp. 283-296. chigbu, n., mbah, e. o., and anyanwu, i., (2018). “assessment of flood risk of cross river state using geographic information system (gis)”. embracing our smart world where the continents connect: enhancing the geospatial maturity of societies, istanbul. gangai, p., selvam, k. and kumaraswamy, k., (2009). “a spatio-temporal patterns of earthquake occurrences in south india”. indian national geographer, 24 (1), pp.48-54. hoque, m.a., (2017). “cyclone disaster mapping, monitoring and management using satellite remote sensing and spatial analysis”. (doctoral dissertation) https://espace.library.uq.edu.au kappes, m. s., keiler, m., von elverfeldt, k., glade, t., (2012). “challenges of analysing multihazard risk: a review”. natural hazards, 64 (2), pp. 1925-1958. 77 a. balasundareshwaran et al / geosi vol 5 no 1 (2020) 65-79 krishna, t.m., ravikumar, g. and krishnaveni, m., (2009). “remote sensing based agricultural drought assessment in palar basin of tamil nadu state, india”. journal of the indian society of remote sensing, 37, pp.9–20. doi.org/10.1007/s12524-009-0008-8 menon, a., ornthammarath, t., corigliano, m. and lai, c.g. (2009). probabilistic seismic hazard macrozonation of tamil nadu in southern india. bulletin of the seismological society of america, 100(3), pp.1320–1341. doi.org/10.1785/0120090071 natarajan, t.k., murty, a.v.s.r., and chandra, d., (1988). “control of surfacial slides by different erosion control techniques”. proceedings 2”. international conference in case histories in geotechnical engineering, rolla, 1, pp. 361-364. ndma, (2016). national disaster management plan, goi, report. oluwasegun, a. h., (2017). “gis analysis of flood vulnerable area in benin-owena river basin nigeria”, indonesian journal of geography, 49 (1), pp. 27-33. doi.org/10.22146/ijg.12777 prasad, n.n.r., and narayanan, p., (2016). “vulnerability assessment of flood-affected locations of bangalore by using multi-criteria evaluation”, annals of gis, 22 (2), pp. 151-162, doi.org/10.1080/19475683.2016.1144649 rahaman, s.a. and aruchamy s., (2017). geoinformatics based landslide vulnerable zonation mapping using analytical hierarchy process (ahp), a study of kallar river sub watershed, kallar watershed, bhavani basin, tamil nadu. modeling earth systems and environment, 3 (1) pp.1-13. doi.org/10.1007/s40808-017-0298-8 rajan s.m.p., and vengadasalam r., (2019): swot and pci based grading of coastal zone: a model emulation from tamil nadu coast, india. human and ecological risk assessment: an international journal. doi.org/10.1080/10807039.2019.1678382 rajan s.m.p., nellayaputhenpeedika m., tiwari s.p. and vengadasalam r., (2019): mapping and analysis of the physical vulnerability of coastal tamil nadu. human and ecological risk assessment: an international journal. doi.org/10.1080/10807039.2019. 1602752 ramkumar, m., santosh, m., abdul rahaman, s., balasundareshwaran, a., balasubramani, k., mathew, m. j., sautter, b., siddiqui, n., usha, k. p., sreerhishya, k., prithiviraj, g., nagarajan, r., thirukumaran, v., menier, d. and kumaraswamy, k., (2019). “tectonomorphological evolution of the cauvery, vaigai, and thamirabarani river basins: implications on timing, stratigraphic markers, relative roles of intrinsic and extrinsic factors, and transience of southern indian landscape”, geological journal, pp.1-42. (issn: 0072-1050) doi.org/10.1002/gj.3520 ramkumar, mu., (2009). “types, causes and strategies for mitigation of geological hazards”, in: ramkumar mu., (ed.) geological hazards: causes, consequences & methods of containment. new india publishing agency, pp. 1-22. roy, d.c. and blaschke, t., (2015). “spatial vulnerability assessment of floods in the coastal regions of bangladesh”, geomatics, natural hazards and risk, 6 (1), pp. 21-44. doi.org/10.1080 /19475705.2013.816785 shankar, v.s., dharanirajan, k., and narsimulu, g., (2015). “cyclone vulnerability zonation of southern part of south andaman, india using multi-criteria weighted overlay techniques”, indian journal of geo-marine sciences, 44 (8), pp. 11811190. 78 a. balasundareshwaran et al / geosi vol 5 no 1 (2020) 65-79 sharma, s.v.s., roy, p. s., chakravarthi, v. and rao, g., (2018). “flood risk assessment using multi-criteria analysis: a case study from kopili river basin, assam, india”. geomatics, natural hazards and risk, 9 (1), pp. 79-93. doi.org/10.1080/19475705.2017.1408705 shrinarayan, j. n., (2015). “study of multi-hazards on urban habitats of india: a case study of ahmedabad city”, thesis submitted to gujarat technological university, ahmedabad. siddiki, u. r., islam, m. n., and aziz, m. n., (2012). “cyclonic track analysis using gis over the bay of bengal”, international journal of applied sciences and engineering research, 1(5), pp. 689-701. doi: 10.6088/ijaser.0020101070. sofowote, u., and dempsey, f., (2015). “impacts of forest fires on ambient near–real–time pm2 in ontario, canada: meteorological analyses and source apportionment of the july 2011–2013 episodes. atmospheric pollution research, 6(1), 1-10. udani, p.m., and mathur, d.k., (2016). “flood hazard vulnerability mapping using remote sensing and gis: a case study along the villages of anand taluka”, advances in applied science research, 7 (3), pp. 214-221. udo, e.a., ojinnaka, o.c., baywood, c.n., and gift. u.a., (2015). “flood hazard analysis and damage assessment of 2012 flood in anambra state using gis and remote sensing approach”, american journal of geographic information system, 4 (1), pp. 38-51. undp (2012). “disaster risk reduction programme”, united national development programme. (date accessed: 28/07/2018) https://www.in.undp.org/content/india/en/home/operations/projects/closed/goiundp_ disaster riskreductionproject.html 79 multi-hazard zonation for effective management of disasters in tamil nadu 1. introduction 2. methods 3. results and discussion 3.1 earthquake 3.2 drought 3.3 cyclone and storm surge 3.4 landslide 3.5 flood 3.6 forest fire 3.7 multi-hazard zonation 4. conclusion references 77 research article development of web-based gis alert system for informing environmental risk of dengue infections in major cities of pakistan naureen zainab 1, aqil tariq 2,* , saima siddiqui 3 1department of computer software engineering, military college of signals, national university of science and technology (nust), islamabad, 44000, pakistan 2state key laboratory of information engineering in surveying mapping and remote sensing (liesmars), wuhan university, wuhan, 430079, china 3department of geography, university of punjab, lahore, 54590, pakistan received 23 november 2020/revised 10 march 2021/accepted 19 march 2021/published 25 april 2021 abstract dengue is one of the emerging major public health problems, and its incidence varies with climate conditions. it affects millions of people's lives owing to unusual socioeconomic conditions and epidemiological factors. this study was designed to build a web-based gis alert system for dengue data management and analysis which would centralize information and make it accessible to all relevant stakeholders before, during, and after crises. three geographical regions were selected in this study. the user interface of the dengue alert system was developed based upon mapguide. results indicate that risk level was mainly associated with breteau index. karachi and lahore were at their highest risk, i.e., level 4. islamabad and chakwal were also at the highest risk, i.e., level 4. attock had high risk, i.e., level 3 followed by haripur with minimal level 1. the high breteau index showed a direct relationship to high potential transmission of dengue outbreaks, a more significant peak of dengue was the result of monsoons, while smaller peaks were observed due to domestic water storage. hence, it was concluded that monsoon is the best suitable season for the development of dengue. web-based gis alert system for dengue data management and analysis was developed, centralizing information and making it accessible to all relevant stakeholders before, during & after a crisis. this program creation will provide a more analytical forum for advising multiple levels of risk and an experimental method for measuring the effect of different factors on risk level distribution by adjusting the component's weighting. keywords : dengue; gis analysis; gui; alert system; breteau index; weighted overlay 1. introduction dengue is a mosquito-borne virus whose prevalence differs with temperature and weather (chang et al., 2009; gubler, 2006). dengue is rising as one of pakistan's most significant public health problems (asif et al., 2013). in october 2005, after ten years, dengue affected karachi again, and 21 deaths were reported out of 103 confirmed cases (mukhtar et al., 2011). geosfera indonesia *corresponding author. email address : aqiltariq@whu.edu.cn (aqil tariq) vol. 6 no. 1, april 2021, 77-95 p-issn 2598-9723, e-issn 2614-8528 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v6i1.20792 https://orcid.org/0000-0003-1196-1248 https://orcid.org/0000-0003-3020-0233 mailto:aqiltariq@whu.edu.cn 78 naureen zainab et al. / geosfera indonesia 6 (1), 2021, 77-95 the year 2011 was pakistan's worst year for dengue. in 2013 the most affected area was the dengue fever (df) outbreak in pakistan. aedes-aegypti and aedes-albopictus is considered to be the main dengue vectors in south asia, including pakistan. the identification of disease outbreaks is very significant (sirisena et al., 2017). epidemics are silent in contrast to explosions. outbreaks kill or cause sickness before detection (kahn et al., 1975). disease outbreaks can easily cause such hurt, and they can spsread rapidly, too. in the worst scenario, the window of opportunity to minimize this harm could be limited to a few days (thompson et al., 2016). the united states of america spends billions of dollars a year on different forms of safety surveillance. the essential expenses include patient infection control, public health surveillance (phs), air and water inspection, preparation, improved public health, and science services in information technology (kahn et al., 1975). proper and prompt treatment of incidents of sickness can save many meaningful humans lives. the breteau index calculates the number of positive containers per hundred surveyed homes, which in turn represents the distribution of aedine mosquitoes, the dengue vector ( udayanga et al., 2018). an alert system was established in pakistan from a synthesis of geospatial data on the breteau map. the interrelationship was rendered between the breteau index and the temperature. it forms the basis for creating weighted overlays to determine risk levels (attaway et al., 2016). dengue alert system generally predicts four different risk levels for the risk of dengue infections, i.e., highest, high, medium, and minimal ( olubadewo-joshua & ugom, 2019; tran et al., 2020). hence, a web-based application was created from a synthesis of geospatial data related to breteau index and temperature effect in pakistan's major cities. using various weighting factors on the previous history, appropriate weighting factor was evaluated and used to generate the alert for informing environmental risk of dengue infection in major cities of pakistan. it forms the basis for creating weighted overlays to determine levels of risk. the weighting can be adjusted to adjust alarm device sensitivity (bowman et al., 2014). every year pakistan experiences a lot of rain during the mild summer (monsoon) season. the daytime temperature is greater than the night temperature. its good climatic conditions for the growth of dengue mosquitos. in this study, we target six major cities of pakistan because pakistan faces a lot of problems in these regions every year. in this study, we clearly describe the spatio-temporal distributions of dengue cases. the study is novel because its first time correlates the local predominant conditions with dengue prevalence and builds a web-based gis alert system. therefore, this study was designed to build a web-based gis alert system for dengue data management and analysis which would centralize 79 naureen zainab et al. / geosfera indonesia 6 (1), 2021, 77-95 information and make it accessible to all relevant stakeholders before, during, and after crises. 2. methods 2.1. study area the study area includes rawalpindi, haripur, attock, chakwal, lahore, and karachi (figure 1). all metropolitan regions are located in different latitudes and longitude in pakistan. these cities' climate is characterized by four seasons: dry, wet, hot, and cold (abbas, 2013). rawalpindi and lahore experience a monsoonal environment with rainy, hot summers and cool dry winters (wet and dry season); rainfall is typical of pakistan's semi-arid region. karachi also receives monsoon rainfall, but the landscape is different compared to rawalpindi and pakistan (burney et al., 2018). karachi harbor is a secure and majestic natural harbor on the shores of which the town is located. a low-lying coastal area stretches along the harbor's edge. the malir river, a seasonal current, flows through the eastern part of the city, and the seasonal layari river runs through the northern section that is most densely populated. several ridges and small hills occur; the maximum elevation, mango pir, is 585 feet high. figure 1. study area of dengue epidemic-prone districts in pakistan 80 naureen zainab et al. / geosfera indonesia 6 (1), 2021, 77-95 2.2. system design, development, and assumption the alert system had been developed to forecast the risk of infection with dengue. it was presumed that the two variables that were used in the method, namely temperature and breteau scale, were strongly associated with dengue fever infection sensitivity and are of significant geographical significance (kaya et al., 2019). 2.3 data source data on breteau index and affected people from 2006 to 2013 were collected from the national institute of health and governments health departments. the monthly temperature data from 2006 to 2013 was acquired from the pakistan meteorological department of islamabad. 2.4 weighted overlay a web-based application was developed from a synthesis of geospatial data related to the breteau index and temperature (cetin et al., 2019).using various weighting factors on the previous history, appropriate weighting factor was evaluated and was used to generate the alert for informing environmental risk of dengue infection in major cities of pakistan. the breteau index was calculated according to eq. (1) as described by gubler et al. ( 2014), while the risk level was calculated based on the formula generated as eq. (2). breteau index (bi) = number of positive containers houses inspected × 100 (1) risk level = bi (60 + temperature) 40 (2) when the breteau index value is zero, the risk level will be zero too, even in the case of high temperature. for instance, in similar temperatures in two different cities, two different risk levels can be observed due to different breteau indexes. 2.5 risk levels dengue risk levels were classified (table 1) into four different groups based on the developed formula of the risk level. the breteau index against these four risk levels is also analyzed. it was assumed that if breteau index is high, then the risk level is also high as breteau index and risk levels are directly proportional to each other (table 2). 81 naureen zainab et al. / geosfera indonesia 6 (1), 2021, 77-95 table 1. risk levels (gubler et al., 2014) classification risk level level 1 0<risk level<=300 level 2 301<=risk level<=600 level 3 600<=risk level<=1200 level 4 risk level>1200 table 2. breteau index according to risk levels (gubler et al., 2014) classification risk level breteau index level 1 0<risk level<=300 0< bi<=4 level 2 301<=risk level<=600 5<= bi <=9 level 3 600<=risk level<=1200 10<= bi <=19 level 4 risk level>1200 bi >=20 2.6 prevention or management of dengue borne vector for confined risk level the adoption of integrated pest management did the management of dengue vectors at confined four risk levels. integrated pest management is the pest population's level to check the pest below the economic injury level using all possible control measures (novotny et al., 2007). recommendations regarding each risk level were given on the basis of ipsm strategies. there are specific preventive and control measures recommended for each alert level shown in table 3. table 3. preventive measures against each risk level (novotny et al., 2007) classification breteau index risk level actions level 1 0< bi<=4 0<risk level<=300 intimately monitor the sanitary condition to prevent and manage the various breeding places. weekly inspection of breeding places and likely to eradicate immediately. try to eliminate the fresh and stagnant water pounds. level 2 5<= bi <=9 301<=risk level<=600 the public is advised to monitor the breeding places efficiently within 3-4 days and eliminate their possible infesting or breeding heaven within their premises. level 3 10<= bi <=19 600<=risk level<=1200 along with regular monitoring, eliminate all possible breeding potential through conducting special operations on a regular basis. launch task-oriented forces to create awareness among people regarding dengue elimination programmed. level 4 bi >=20 risk level>1200 launch a task-oriented force to create awareness among people regarding dengue elimination programmed and give them responsibilities to restrain the potential breeding places by allotting them specific territories. private competitive pest control and management contractor must be employed to control and eradicate the arising potential mosquito problem. 82 naureen zainab et al. / geosfera indonesia 6 (1), 2021, 77-95 2.7 conceptual design the present study's concept was to build a web-based gis alert system both online and offline for dengue data management and analysis, centralizing the information and making it accessible to all relevant stakeholders before, during, and after a crisis. the system aimed to ensure timely availability of information on health care services. the project data were mapped accurately and with geographic features displayed. maps were drawn according to pre-set parameters in the present framework, and then the web browser showed the map in a .jpeg format. the users can create and display a new map by adjusting the parameters. on the server-side, this sort creates a heavy load. the server-side had regional info, gis tools, and a system with hundreds of complex reports on the interface (cetin, 2015). the systematic conceptual diagram of the web-based gis alert system is shown in figure 2. figure 2. conceptual design of web-based gis alert system. 2.8 user interface (ui) mapguide maestro is a mapguide open-source map authoring tool. mapguide maestro strives to support the capabilities of the open-source application mapguide. both spatial and non-spatial details have been contained in sql server express, which is a free database service that fits well with any web application platform (zavlavsky, 2000). the graphical user interphase (mapguide) was systematically developed, as shown in figure 3. 83 naureen zainab et al. / geosfera indonesia 6 (1), 2021, 77-95 figure 3. graphical user interphase (mapguide) 2.9 component of web-based gis alert system three components of the web-based gis alert system (figure 4) were used as: (1) dengue information databases (2) gis layers and maps (3) queries and reports figure 4. components of web-based gis alert system overall, the system describes the risk levels of dengue infection in major cities of pakistan, classifying them into three geographical regions. a web-based application was created from a synthesis of geospatial data related to the breteau index and temperature effect in pakistan's major cities. currently, statistics on the breteau index and temperature are 84 naureen zainab et al. / geosfera indonesia 6 (1), 2021, 77-95 displayed in a table format that is difficult for interpretation by general users. this project allows the visualization of the breteau index and temperature information in a spatial pattern and association with four risk levels, which enhances public awareness. dengue alert system describes the risk level of dengue infections from 2006 to 2013 in major cities of pakistan. it can also predict the current risk level of dengue in any district of pakistan. it can predict four different risk levels for the risk of dengue infections, i.e., highest, high, medium, and minimal. 3. results and discussion 3.1 temporal changes in temperature and breteaux index a good association between the two variables has been identified from the temporal change in temperature and the breteau scale (bozdogan et al., 2021). higher breteau index focused primarily in the summer and autumn when higher temperatures prevailed. results shown in figure 5a indicate the temporal changes in breteau index in september 2010 in selected study sites. the breteau index of lahore and islamabad represented by green color was high. the breteau index of karachi denoted by blue color was medium. the breteau index of chakwal and haripur represented by yellow color was minimal, and the breteau index of attock represented by gray showed no risk. similarly, the temporal changes in temperature in major cities of pakistan figure 5b indicate that karachi had high temperature while the remaining cities showed low temperature. the high temperature was represented by dark gray color, and low temperature was represented by light gray. the effect of temperature on the weighted overlay product can be calculated when the temperature and the breteaux index are overlaid. the temperature was not considered to be the main factor deciding the level of risk according to the given weighting, and when the breteau scale equals zero, the risk level was also zero, irrespective of the temperature increase. the cities with a high breteau index are at a higher risk level. lahore and islamabad's temperature was low compared to karachi, but they had a high-risk level due to the high breteau index. breteau index of attock was zero, so there was no risk; however, the attock temperature was 28oc, similar to chakwal 27.6oc. 85 naureen zainab et al. / geosfera indonesia 6 (1), 2021, 77-95 figure 5a. breteau index of september 2010 in major cities of pakistan, figure 4b. temperature of september 2010 in major cities of pakistan, figure 4c. breteau index of september 2011 in major cities of pakistan, figure 4d. temperature of september 2011 in major cities of pakistan. figure 5c and figure 5d show the breteau index and temperature of september 2011 in selected study sites. attock and haripur very high followed the breteau index of karachi, lahore, islamabad, rawalpindi, and chakwal. the temperature of karachi and lahore was high as compared to other cities. figure 5d represents that karachi and lahore were at their highest risk and the temperature of these two cities was also high. rawalpindi, islamabad, and chakwal were also at the highest risk, but they had a low temperature as compared to karachi and lahore. attock had high risk, and the temperature was low. haripur showed minimal risk and had a low temperature. rawalpindi and attock's temperature showed a similar trend but had different risk levels due to different breteau index. web-based generated map of the risk levels of dengueshows that risk level was high in those cities which had high breteau index. results indicate that karachi and lahore were at their highest risk, i.e., level 4. islamabad and chakwal were also at the highest risk, 86 naureen zainab et al. / geosfera indonesia 6 (1), 2021, 77-95 i.e., level 4. attock had high risk, i.e., level 3 followed by haripur with minimal level 1. hence, it is concluded that risk level was mainly associated with breteau index, if breteau index was high, then the risk level was also high, so this is the main reason for which the highest weightage is assigned to the breteau index (gungor et al., 2020). temperature also plays a significant role because the risk level was high in mostly the summer months, which had a high temperature. if the temperature was high, mosquito's growth rates were also high because high temperature helps in breeding aedes aegypti and aedes albopictus mosquitoes. 3.2 peaks of dengue based on the analysis of risk levels from 20062013 in major cities of pakistan results from the analysis of dengue risk levels from 2006 to 2013 in major cities of pakistan indicated that the high risk of dengue from 2006 to 2013 was mostly observed in the month of september, october, and november (table 4). the dengue-related deaths were reported between the months from september to november. dengue case-load registered during these months, and the reports declined rapidly during and after december. the high breteau index showed a major direct relationship to the high potential transmission of dengue outbreaks in the study sites. two peaks of dengue were shown in the form of risk levels. the formation of a more significant peak of dengue resulted from monsoon rains in which water was filled at the low-lying places. smaller peaks of dengue were formed in the dry season due to domestic storage of water. it was seen that transmission of dengue during the monsoon and after monsoon was maximum than that of the dry season. finally, it was concluded that monsoon is the best suitable season for the reproduction, fecundity, survival, growth, and development of dengue. dengue fever is estimated to affect 50 to 100 million people with 1/2 million lifethreatening infections globally in a year as of 2010. it has risen 30-fold significantly in frequency between 1960 and 2010. in pakistan in the year 2010, there were more than 7000 positive confirmed cases of dengue.with rising epidemics, dengue fever has become a significant disease in pakistan. given pakistan's government's efforts, especially in punjab, the high treatment cost has hindered pakistan's ability to control epidemics. dengue-fever mortality in pakistan in the summer of 2011 was over 300 people, and epidemic incidence was over 14,000 infections. the outbreaks mainly occurred in the region of lahore, punjab, pakistan. 87 naureen zainab et al. / geosfera indonesia 6 (1), 2021, 77-95 table 4. results from the analysis of dengue risk levels from 2006 to 2013 in major cities of pakistan city dengue risk 2006 2007 2008 2009 2010 2011 2012 2013 k a r a c h i duration jan apr jul aug jan, sep to dec aug to dec jan apr aug to dec jan apr to dec jan to dec all over the year minimum jan apr jul aug jul dec jan jan aug sep dec jan apr aug dec jan apr to jul jan to sep jan to aug dec moderate sep sep sep dec sep aug nov dec dec sep highest oct nov oct nov oct nov oct nov oct nov sep oct oct nov oct nov l a h o r e duration jan aug to dec sep dec jul dec apr dec apr aug to dec mar to dec minimum jul aug sep dec dec jan, aug dec dec jul aug dec apr jul apr aug dec mar to july sep moderate oct sep oct sep sep oct sep aug nov dec sep aug dec highest nov nov oct nov nov oct nov sep oct oct nov oct nov a tt o c k duration oct to dec oct to dec oct nov july sep to dec minimum sep sep dec dec jul dec nov moderate oct nov oct nov oct oct oct sep nov highest nov nov nov oct continued 88 naureen zainab et al. / geosfera indonesia 6 (1), 2021, 77-95 city dengue risk 2006 2007 2008 2009 2010 2011 2012 2013 r a w a lp in d i duration sep to dec sep to dec sep dec jun to dec jun to dec minimum jul aug aug dec dec sep dec jun jul aug jul aug dec moderate oct sep oct sep sep oct nov dec sep highest nov nov oct nov nov oct nov sep oct oct nov is la m a b a d duration aug to dec sep to dec sep to nov sep to dec jun to dec aug to dec minimum dec sep dec jun jul aug dec aug to nov aug sep dec moderate sep oct oct sep sep oct nov oct highest nov nov oct nov oct nov nov sep oct nov h a r ip u r duration sep to nov oct nov sep to nov apr jul to dec minimum dec dec dec sep apr jul aug sep dec sep oct sep oct nov moderate oct sep oct oct highest nov oct, nov nov oct nov nov c h a k w a l duration no case jan nov sep to nov sep to nov minimum oct, nov sep sep nov moderate oct, nov jan oct oct nov highest nov nov sep note : = no case 89 naureen zainab et al. / geosfera indonesia 6 (1), 2021, 77-95 3.3 application web-based gis alert system for web-based gis alert system application, a user can select url localhost/dengue. the dengue support system will display. for login purposes, the user can click on the login option. before getting detailed information, the customer will be asked to enter the id and password. if the user identification and password are wrongly entered, an error message will pop up, "your attempt to login is not successful. please try again," and the user will be asked to register until the correct information is typed in. this system would help to protect data security under study. the existing database had included eight years' data. the application was developed monthly, so a first select year and then the month, and then click/check the risk levels. database contents and collections could be expanded in the future. after selecting the month and the year, the selected year's risk level will be displayed. users can also zoom the areas concerned by clicking on the option zoom rectangle. this feature provides the consumer a general understanding of the environment impacted and theoretically affected. one of the most important functions of this system was to find the current risk level of any district based upon the breteau index and temperature. by entering the breteau index and temperature, the system can find the current risk level of dengue of any pakistan district by selecting the district in the drop-down list. results shows that the user selected district faisalabad entered breteau index 7.53 and temperature 21.4 and then clicked on select, the risk level of faisalabad was displayed. the blue color represents that it was at level 2. the dengue alert system was capable of generating the reports of risk levels of each month. the reports of the risk level of dengue in september 2011 along with "actions to be taken" at each level. the system was also capable of generating the graphical representation of the risk level of each month (figure 6). figure 6. graphical representation of risk level of september 2011 1741.9 254.15 2044.5 1456.18 1457.7 1342.7 0 500 1000 1500 2000 2500 chakwal haripur islamabad karachi lahore rawalpindi series1risk level 90 naureen zainab et al. / geosfera indonesia 6 (1), 2021, 77-95 it has been seen from the data and observed that high dengue indicators are in august, september, october, and november, i.e., after july, which have a high temperature in pakistan. if the breteau scale is 0, the risk level will also be zero, regardless of how high the temperature is. it is concluded that risk level is mainly associated with breteau index, if breteau index is high, then risk level is also high, so this is the main reason due to which highest weightage is assigned to breteau index, but temperature also plays a significant role because risk level is high in mostly the months which have a high temperature. if the temperature is high, mosquito growth chances are also high because high temperature helps in the breeding of aedine mosquitoes. there is no chance even if the temperature is very high without the existence of aedine mosquitoes. for instance, if the temperature is similar for two cities, they have very different risk levels. the device may be combined with other potential factors. human population growth is a significant dengue consideration because the desert region containing many mosquitoes is not dangerous. if the weather around the house is suitable for dengue, then dengue infections will be high. the moisture and containers may be important influences. eventually, mosquito species often play a part. the system is not without limitations. it is a web-based application, and for this application, internet connectivity must require. if the internet speed is slow, this application will not work properly because it requires high bandwidth. according to dengue outbreaks, the likelihood of dengue is caused by many variables in real life including the virus and the climate. the application of temperature and breteau index offers one element of risk assessment, concentrating on exposure impact calculation alone. certain considerations might be applied to the system's robustness. similar results/an online alert system (gis) were developed. the interrelationship between various indices and temperature was measured by wong et al., (2007), who observed that the inference forms the rationale for the generation of weighted overlays to define risk levels. weighting can be adjusted to set the sensitivity of the alert system. they concluded that the alert system offers one objective means to defining the risk of dengue in a society, which would not be affected by the incidence of the infection itself similarly, shen et al. (2015) conducted a study to explore the associations between the monthly number of dengue fever (df) cases and possible risk factors in guangzhou, a subtropical city of china. in their study, a total of 39,697 df cases were detected in guangzhou. dengue fever incidence showed an obvious seasonal pattern, with most cases occurring from june to november. they observed that the current month's breteau index, average temperature, previous month's minimum temperature, and tave were positively 91 naureen zainab et al. / geosfera indonesia 6 (1), 2021, 77-95 associated with dengue fever incidence. they also concluded that the mosquito density, tave, and tmin play a critical role in dengue fever transmission in guangzhou. in another study, liyanage et al., (2019) used an interrupted time-series design with a non-linear extension, and evaluated the impact of vector control interventions from june 22, 2014, to dec 29, 2016, in panadura, a high-risk moh division in western province, sri lanka. they used dengue notification and larval survey data to estimate the reduction in breteau index and dengue incidence before and after the intervention using two separate models, adjusting for time-varying confounding variables (i.e., rainfall, temperature, and the oceanic niño index). they found that breteau index is an essential index for controlling and measuring the extent of vector control in dengue transmission. bajwala et al (2020) conducted a study using mean temperature (°c), relative humidity (%), and precipitation (rainfall in mm) as climatic parameters affecting vector ecology. they recorded the peak number of cases was recorded in the post-monsoon period. they proposed that presence of some serologically positive cases even during dry months in this study could probably be reflective of the year-round activity of the dengue vector. moreover, some advanced techniques, i.e., artificial intelligence-based mathematical model and fuzzy logic, could be a suitable option to implement control measures in dengueprone areas. adak & jana (2021) developed an artificial intelligence-based mathematical model taking the three stegomyia indices, namely house index, breteau index, and container index. the project's concept was to build a web-based gis alert system for dengue data management and analysis, centralizing information and making it accessible to all relevant stakeholders before, during & after a crisis situation. the system aims to ensure timely availability of information on health care services and project data, mapped accurately and with geographic features displayed, designed an alert system for users to visualize the spatial distribution of the risk of exposure to aedine mosquito in the local setting. the system complements information on the incidence of infection and is a more objective way of defining risk levels. overall, the system describes the risk levels of dengue infection in major cities of pakistan, classifying them into three geographical regions, and can predict all districts of pakistan's risk levels. a web-based application was created from a synthesis of geospatial data related to breteau index and temperature effect in pakistan's major cities. future alignment of this program with practices of prevention and control of dengue fever will be important. this pilot project may be associated with the various government departments involved. similar systems could be built and adapted to estimate exposure to other diseases, such as bird flu, for which environmental factors are critical for propagation. 92 naureen zainab et al. / geosfera indonesia 6 (1), 2021, 77-95 the program could become a tool for local, regional, and even national health authorities and other stakeholders in the long run. 4. conclusion the user interface of the dengue alert system was developed based upon mapguide. the inter-relationship between breteau index and the temperature was developed using a web-based gis application. four different patterns mapping were developed for the risk of dengue, i.e., highest, high, medium, and minimal. maps were created using pre-set criteria, and the map was shown as an image by the web browser.a high risk of dengue was found in august, september, october, and november, i.e., after july, in which had high temperature was noted. risk level was found mainly associated with breteau index; if breteau index was high, then risk level was also high. when the breteau index equals zero, the risk level was zero, irrespective of the temperature rise. temperature also played a significant role because the risk level was high, mainly in the months with high temperatures. there was no risk without aedine mosquitoes' presence even if the temperature was very high. for instance, if the temperature was similar for two cities, they depicted very different risk levels. this study's significance is introducing a new method for expressing the alert system on a spatial scale. the web-based alert system should no longer be expressed in statistical and textual formats, but that spatial graphics could be incorporated. in addition, the weighted overlay allows the users to weigh the contribution of factors affecting the exposure risk to dengue. conflict of interest the authors declare that there is no conflict of interest. acknowledgments authors gratefully acknowledge the support received from dr. mukhtar senior scientific officer (entomology), ex. head of department of zoonotic and vector-borne diseases and thanks to dr jan muhammad director pakistan meteorological department for monthly mean temperature data. we are thankful to dr. m. farrukh sultan, dpc, edoh, lahore. the authors would also like to express their appreciation to rana naveed mustafa (narc), naveed yaqoob, department of mathematics, qau islamabad and azmat ali sr. project manager erp (it/mis) at agribusiness support fund for their kind cooperation. this research was supported by the national natural science foundation of china (no. 41871345). 93 naureen zainab et al. / geosfera indonesia 6 (1), 2021, 77-95 references abbas, f. (2013). analysis of a historical (1981-2010) temperature record of the punjab province of pakistan. earth interactions, 17(15), 1–23. https://doi.org/10.1175/2013ei000528.1. adak, s., & jana, s. (2021). a study on stegomyia indices in dengue control: a fuzzy approach. soft computing a fusion of foundations, methodologies and applications, 25(1), 699–709. https://doi.org/10.1007/s00500-020-05179-x. asif, m., tripathi, n. k., & ahmed, s. (2013). towards near real time public health surveillance (a decision support system for public health surveillance). international journal of computer applications, 61(21), 45–50. attaway, d. f., jacobsen, k. h., falconer, a., manca, g., & waters, n. m. (2016). risk analysis for dengue suitability in africa using the arcgis predictive analysis tools (pa tools). acta tropica, 158, 248-257. https://doi.org/10.1016/j.actatropica.2016.02.018. bajwala, v. r., john, d., rajasekar, d., eapen, a., & murhekar, m. v. (2020). burden of dengue with related entomological and climatic characteristics in surat city, gujarat, india, 2011–2016: an analysis of surveillance data. the american journal of tropical medicine and hygiene, 103(1), 142-148. https://doi.org/10.4269/ajtmh.19-0967. bowman, l. r., runge-ranzinger, s., & mccall, p. j. (2014). assessing the relationship between vector indices and dengue transmission: a systematic review of the evidence. plos neglected tropical diseases, 8(5). https://doi.org/10.1371/journal.pntd.0002848. bozdogan sert, e., kaya, e., adiguzel, f., cetin, m., gungor, s., zeren cetin, i., & dinc, y. (2021). effect of the surface temperature of surface materials on thermal comfort: a case study of iskenderun (hatay, turkey). theoretical and applied climatology, 1–11. https://doi.org/10.1007/s00704-021-03524-0. cetin, m. (2019). the effect of urban planning on urban formations determining bioclimatic comfort area’s effect using satellitia imagines on air quality: a case study of bursa city. air quality, atmosphere & health, 12(10), 1237-1249. https://doi.org/10.1007/s11869-019-00742-4. cetin, m., adiguzel, f., gungor, s., kaya, e., & sancar, m. c. (2019). evaluation of thermal climatic region areas in terms of building density in urban management and planning for burdur, turkey. air quality, atmosphere & health, 12(9), 1103-1112. https://doi.org/10.1007/s11869-019-00727-3. cetin, m. (2015). using gis analysis to assess urban green space in terms of accessibility: case study in kutahya. international journal of sustainable development & world ecology, 22(5), 420-424. https://doi.org/10.1080/13504509.2015.1061066. chang, a. y., parrales, m. e., jimenez, j., sobieszczyk, m. e., hammer, s. m., copenhaver, d. j., & kulkarni, r. p. (2009). combining google earth and gis mapping technologies in a dengue surveillance system for developing countries. international journal of https://www.ijcaonline.org/archives/volume61/number21/10216-5083 94 naureen zainab et al. / geosfera indonesia 6 (1), 2021, 77-95 health geographics, 8(1), 1–11. https://doi.org/10.1186/1476-072x-8-49. gubler, d. j. (2006). dengue/dengue haemorrhagic fever: history and current status. in novartis foundation symposium (vol. 277, p. 3). chichester; new york; john wiley. gubler, d. j., ooi, e. e., vasudevan, s., & farrar, j. (2014). dengue and dengue hemorrhagic fever. oxfordshire : cabi. gungor, s., cetin, m., & adiguzel, f. (2020). calculation of comfortable thermal conditions for mersin urban city planning in turkey. air quality, atmosphere and health, 1–8. https://doi.org/10.1007/s11869-020-00955-y. kahn, t. c., cameron, j. t., & giffen, m. b. (1975). methods and evaluation in clinical and counseling psychology. elmsford, ny: pergamon press. kaya, e., agca, m., adiguzel, f., & cetin, m. (2019). spatial data analysis with r programming for environment. human and ecological risk assessment, 25(6), 1521– 1530. https://doi.org/10.1080/10807039.2018.1470896. liyanage, p., rocklöv, j., tissera, h., palihawadana, p., wilder-smith, a., & tozan, y. (2019). evaluation of intensified dengue control measures with interrupted time series analysis in the panadura medical officer of health division in sri lanka: a case study and cost-effectiveness analysis. the lancet. planetary health, 3(5), e211–e218. https://doi.org/10.1016/s2542-5196(19)30057-9. mukhtar, m., tahir, z., baloch, t., mansoor, f., & kamran, j. (2011). entomological investigations of dengue vectors in epidemic-prone districts of pakistan during 2006– 2010. world health organization regional publications. south east asia series. novotny, v., miller, s. e., hulcr, j., drew, r. a. i., basset, y., janda, m., … weiblen, g. d. (2007). low beta diversity of herbivorous insects in tropical forests. nature, 448(7154), 692–695. https://doi.org/10.1038/nature06021. olubadewo-joshua, o., & ugom, k. m. (2019). application of geospatial techniques in the locational planning of health care centers in minna, nigeria. geosfera indonesia, 3(3), 59-72. https://doi.org/10.19184/geosi.v3i3.8754. shen, j. c., luo, l., li, l., jing, q. l., ou, c. q., yang, z. c., & chen, x. g. (2015). the impacts of mosquito density and meteorological factors on dengue fever epidemics in guangzhou, china, 2006-2014: a time-series analysis. biomedical and environmental sciences, 28(5), 321–329. https://doi.org/10.3967/bes2015.046. sirisena, p., noordeen, f., kurukulasuriya, h., romesh, t. a., & fernando, l. k. (2017). effect of climatic factors and population density on the distribution of dengue in sri lanka: a gis based evaluation for prediction of outbreaks. plos one, 12(1), e0166806. https://doi.org/10.1371/journal.pone.0166806. burney, s. a., barakzai, m. a. k., & james, s. e. (2020). forecasting monthly maximum temperature of karachi city using time series analysis. pakistan journal of engineering, technology & science, 7(2). https://doi.org/10.22555/pjets.v7i2.2439. https://onlinelibrary.wiley.com/doi/book/10.1002/0470058005#page=13 https://books.google.co.id/books?hl=id&lr=&id=tl_ybaaaqbaj&oi=fnd&pg=pr5&dq=gubler+dengue+2014&ots=ctlavgemxi&sig=poapgum45gpxtfhkxsje09knnje&redir_esc=y#v=onepage&q=gubler%20dengue%202014&f=false https://books.google.co.id/books?hl=id&lr=&id=tl_ybaaaqbaj&oi=fnd&pg=pr5&dq=gubler+dengue+2014&ots=ctlavgemxi&sig=poapgum45gpxtfhkxsje09knnje&redir_esc=y#v=onepage&q=gubler%20dengue%202014&f=false https://www.sciencedirect.com/book/9780080178622/methods-and-evaluation-in-clinical-and-counseling-psychology https://www.sciencedirect.com/book/9780080178622/methods-and-evaluation-in-clinical-and-counseling-psychology https://apps.who.int/iris/bitstream/handle/10665/171002/db2011v35p99.pdf;jsessionid=455d9654c6994338d775c931e795e6ef?sequence=1 https://apps.who.int/iris/bitstream/handle/10665/171002/db2011v35p99.pdf;jsessionid=455d9654c6994338d775c931e795e6ef?sequence=1 https://apps.who.int/iris/bitstream/handle/10665/171002/db2011v35p99.pdf;jsessionid=455d9654c6994338d775c931e795e6ef?sequence=1 95 naureen zainab et al. / geosfera indonesia 6 (1), 2021, 77-95 thompson, r. n., gilligan, c. a., & cunniffe, n. j. (2016). detecting presymptomatic infection is necessary to forecast major epidemics in the earliest stages of infectious disease outbreaks. plos computational biology, 12(4). https://doi.org/10.1371/journal.pcbi.1004836. tran, b. l., tseng, w. c., chen, c. c., & liao, s. y. (2020). estimating the threshold effects of climate on dengue: a case study of taiwan. international journal of environmental research and public health, 17(4), 1–17. https://doi.org/10.3390/ijerph17041392. udayanga, l., gunathilaka, n., iqbal, m. c. m., najim, m. m. m., pahalagedara, k., & abeyewickreme, w. (2018). empirical optimization of risk thresholds for dengue: an approach towards entomological management of aedes mosquitoes based on larval indices in the kandy district of sri lanka. parasites and vectors, 11(1), 368. https://doi.org/10.1186/s13071-018-2961-y. wong, n. s., law, c. y., lee, m. k., lee, s. s., & lin, h. (2007). an alert system for informing environmental risk of dengue infections. in p. c. lai & a. s. h. mak (eds.), gis for health and the environment: development in the asia-pacific region with 110 figures (pp. 171–183). springer berlin heidelberg. https://doi.org/10.1007/978-3-540-71318-0_12. zavlavsky, i. (2000). a new technology for interactive online mapping with vector markup and xml. cartographic perspectives, 0(37), 65-77–77. https://doi.org/10.14714/cp37.810. 40 ifeyinwa sarah obuekwe et al. / geosfera indonesia 6 (1), 2021, 40-54 research article quantifying the significance of distance to temporal dynamics of covid-19 cases in nigeria using a geographic information system ifeyinwa sarah obuekwe1, 2* , umar saleh anka1,3 , sodiq opeyemi ibrahim1,3 , usman ahmad adam4 1nigerian environmental society, nigeria 2department of microbiology, faculty of life sciences, university of benin, benin city, edo state, pmb. 1154, nigeria 3 department of geography, faculty of earth and environmental sciences, bayero university, kano state, nigeria 4 department of geography, sa’adatu rimi college of education, kumbotso, kano, nigeria received 16 december 2020 /revised 8 april 2021 /accepted 17 april 2021 /published 25 april 2021 abstract the coronavirus disease 2019 (covid-19) is caused by a new strain of coronavirus that spreads primarily by close contact. although nigeria adopted lockdown measures, no defined strategies were used in setting the distance threshold for these lockdowns. hence, understanding the drivers of covid-19 is pivotal to an informed decision for containment measures in the absence of vaccines. spatial and temporal analyses are crucial drivers to apprehending the pattern of diseases over space and time. thus, this study aimed to quantify the significance of distance to the temporal dynamics of covid-19 cases in nigeria using the geographic information system. incremental spatial autocorrelation was used to analyze datasets of each month in arcgis. march, april, may, and june exhibited patterns with no significant peaks, while july and august exhibited patterns with two statistically significant peaks. the first and second peaks of july were 301,338.39 and 365,947.83 meters, respectively, while august was 301,338.39 and 336,128.09 meters, respectively. therefore, a significant difference in the clustering of covid19 over distances between july and august was established. this indicated that progression in the spread of the virus increased the virus's spatial coverage while the distance of risk of exposure decreased. this study's findings could be utilized to establish maximum movement restriction areas to contain the spread of covid-19. keywords: distance; incremental spatial autocorrelation; covid-19; disease; nigeria 1. introduction covid-19 is a respiratory disease that emerged in late 2019 caused by a new coronavirus that presents pneumonia-like symptoms. therefore, it has high transmission competence and spreads primarily when people are in close contact (dhama et al., 2020). geosfera indonesia *corresponding author. email address : ifeyinwa.obuekwe@uniben.edu (ifeyinwa sarah obuekwe) vol. 6 no. 1, april 2021, 40-54 p-issn 2598-9723, e-issn 2614-8528 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v6i1.21405 https://orcid.org/0000-0002-0187-7731 https://orcid.org/0000-0002-7984-0947 https://orcid.org/0000-0002-4635-8521 mailto:ifeyinwa.obuekwe@uniben.edu 41 ifeyinwa sarah obuekwe et al. / geosfera indonesia 6 (1), 2021, 40-54 covid-19 is causing an ongoing pandemic in many countries and territories, and therefore, it is a global health crisis (mckee & stuckler, 2020). infected people are accommodated and isolated in designated health facilities across the world for treatment. in the absence of a vaccine to prevent or aid speedy recovery, a significant concern is that, as the number of infected people increases, the healthcare system will be overwhelmed (murray et al., 2020). nevertheless, efforts to prevent further spreading are ongoing in many nations as vaccines, and antiviral drugs are awaited. in response to the worldwide covid-19 outbreak, many sub-saharan africa countries have implemented strict lockdown measures to emulate high-income countries to contain the spread of the virus (teachout & zipfel, 2020). however, severe restrictions placed on people's travel may impact different livelihoods, especially the world’s poorest people (woodhill, 2020). gradually, the impact of the lockdown is unfolding and remains largely guesswork. despite the likelihood of severe impact of lockdown on livelihoods, there is no adequate information to help guide the threshold with which movement restriction can be placed. details about places where cases may arise concerning identified cases could help enhance movement restriction decisions. wang et al. (2021) claimed that the temporal trends of covid-19 across space require deliberation when considering lifting lockdown. this makes the need for a timely knowledge of the temporal and spatial patterns of covid-19 transmission. however, knowledge of the geographical mean distances between the locations of cases and the direct estimation of distances between sequential cases requires both the recognition of cases and their infectors (salje et al., 2016). such contact tracing efforts are nearly impossible because of two major restrains, cost and time. thus, limited data hinders the ability to characterize the space and time scales where cases tend to occur. estimating mean transmission distances have been possible previously only in situations where there is available data for most cases in a transmission network or detailed epidemiological data on who infected whom (memish et al., 2014; marziano et al., 2017; yang et al., 2020). in the absence of data on where covid-19 cases were discovered in nigeria, there is the need to seek alternatives that can help in decision-making before the spread of the virus is beyond management capacity. hence, this study's novelty was that it demonstrated an approach to quantify the significance of temporal dynamics in the mean transmission distance of recorded covid-19 cases in nigeria. this was based on the use of geographic information system 42 ifeyinwa sarah obuekwe et al. / geosfera indonesia 6 (1), 2021, 40-54 software, data of the monthly covid-19 recorded cases, and the coordinates of the capital of the thirty-six (36) states in nigeria and the federal capital territory. this study aimed to quantify the significance of distance to the temporal dynamics of covid-19 cases in nigeria using the geographic information system. 2. methods 2.1 description of study area nigeria covers an area of 923,769 square kilometers, and it’s bordered by different countries on the north, south, east and west. on the north is niger and chad, south is gulf of guinea while the east and west are cameroon, benin and niger respectively (national bureau of statistics, 2011). 2.2 study area ecosystem the coast of nigeria is surrounded by flowering trees in marshes which are traversed by estuaries and rivers as well as the great niger basin (national bureau of statistics, 2011).eastwards however, lie successive belts of tropical rain forests and the undulating plateau, rising from 609.6 meters on the average to 1,828.8 meters. grassland vegetation interspersed with trees and shrubs is seen midway north of the country however, this stops at the north-east desert which is the grassy coast region. river niger receives its benue counterpart at lokoja, and from there flows into the atlantic ocean for about 547 kilometers. its tributaries include include sokoto, kaduna and anambra rivers (national bureau of statistics, 2011). however, the benue river is fed by two rivers namely katsina-ala and gongola. nigeria has other rivers which include cross river, benin and ogun rivers (national bureau of statistics, 2011). 2.3 study area population and geopolitical zones the population of nigeria in mid-year of 2020 is estimated at 206,139,589 people based on united nation data (worldometer, 2020). nigeria practices democratic system of government and each state and the federal capital territory has their elected officials. the elected officials are from political parties within the country. 43 ifeyinwa sarah obuekwe et al. / geosfera indonesia 6 (1), 2021, 40-54 figure 1. nigeria 36 states and the federal capital territory in their geopolitical zones (gis lab geography department, 2020) 2.4 research design the study was an explorative research. due to the newness of covid-19, explorative research has been adopted in several studies (scarpone et al., 2020) as it offers researchers the opportunity to study a problem that has not been thoroughly studied in the past. 2.5 data and sources of data the study made use of publicly available covid-19 and spatial datasets. the covid-19 dataset used include monthly recorded cases from march to august, 2020. the data were downloaded from nigeria centre for disease control (2020) website (https://covid19.ncdc.gov.ng/). this data is updated once a day (at 23:59 wat).the spatial data used for this study was shapefile of nigeria including states and coordinates of state capitals. the spatial data were sourced from the geographic information system laboratory, department of geography bayero university, kano. https://covid19.ncdc.gov.ng/ 44 ifeyinwa sarah obuekwe et al. / geosfera indonesia 6 (1), 2021, 40-54 2.6 data analysis the monthly covid-19 recorded cases for the 36 states and the federal capital of nigeria were subjected to incremental spatial autocorrelation analysis in arcgis 10.5 with the use of a conceptualized fixed distance. the incremental spatial autocorrelation analysis work in such a way that it calculates the moran’s i index and z score of a single data set at multiple distances. z-score is a standard deviation which measures the distance of a raw score from the mean. also, the rule of thumb for pattern analysis like spatial autocorrelation is that the z-score and p-values obtained determine the confidence level which can be used to accept or reject a null hypothesis. hence, the threshold for determining the confidence level of a z-score and p-value is shown in table 1. hence, analyzed fixed distances were derived from each of the possible distance between a data point (a state capital) and all other data points (other state capitals). as in the case of this study, moran’s i index was run for all the possible distances that existed between the 36 states and the federal capital of nigeria. instead of using the moran’s i index value, the distance was used to plot the z scores. this enabled a standardized distance-based comparison of statistical significance using the threshold in table 1. larger positive z scores indicate high significant clustering (table 1). thus, in each of the plots, distances of the first peak and maximum peak were identified, as the first peak indicates lower statistically significant clustering while the maximum peak indicates the distance that clustering or spatial autocorrelation was of most statistical significance in the data set. also, different colors were used to indicate the z-scores each distant point belong to as well as which distance is characterized as a peak. table 1. critical p-values and z-scores for different confident levels (moran, 1948) z-score (standard deviations) p-value (probability) confidence level (%) < -1.65 or > + 1.65 < 0.10 90 < -1.96 or > + 1.96 < 0.05 95 < -2.58 or > + 2.58 < 0.01 99 furthermore, the distance of each state capital to other state capital and the federal capital was first obtained in arcgis via point distance analysis. the obtained distance was then exported to excel where the mean was determined. in addition, bar graph was used to visualize the mean distance and distances where covid 19 clustering were significant. afterwards, 45 ifeyinwa sarah obuekwe et al. / geosfera indonesia 6 (1), 2021, 40-54 distances with significant peaks was compared with the mean distance of each state capital and the federal capital to other state capital and federal capital. the flowchart of the methodology for the study is summarized in figure 2. figure 2. flowchart of the method of the study 3. results and discussion after the index case of covid 19 in february, by the end of march, lagos has recorded 62 cases and was the highest state in nigeria with recorded cases (figure 3). this was followed by the federal capital territory, which had a recorded 9-28 victims. south western states that were closer to lagos were also observed to have recorded 4-8 victims. the cases recorded in kaduna, bauchi, ekiti, edo, benue, enugu, and rivers were within 1-3 while the other states had no recorded cases. alkhamis et al. (2020) also observed that after about a month from the first reported case of covid-19 in kuwait, the size was small despite sporadic infections. gayawan et al. (2020) also stated that covid-19 initially had a slow spread across africa, only for the situation to escalate in the last week of march. in april, although lagos still had the highest recorded cases, the spread of the virus in the north within the addition of one month is a course to worry about (figure 5). kano state that had no recorded case in march had the same range of 77-219 recorded cases with the federal capital territory. this implies that the rate of spread in the north was high in april, despite the federal government imposing a lockdown on lagos, ogun, and abuja on march 30, 2020. the high 46 ifeyinwa sarah obuekwe et al. / geosfera indonesia 6 (1), 2021, 40-54 spread indicates the lockdown was not as effective as that of china's strict lockdown (prem et al., 2020). may's spread exceeds that of march and april combined with kano having more recorded cases than the federal capital territory. despite the lockdown, border porosity, which is an issue in most african countries (okunade & ogunnubi, 2019), makes it hard to restrict mobility effectively. the ability to contain human mobility has been an issue worldwide as migrant workers and travelers have been the mostly affected and responsible for spreading the virus (kuwait government online, 2020; gayawan et al.,2020). there was an increase in the spread of covid-19 between june and july. however, the range of increase in abuja and oyo for july exceeded kano, edo, delta, and rivers state (figure 9 and figure 11). it was also observed that cross river was the last state to record the covid19 case in nigeria (figure 11). as of august, all the states in nigeria had a recorded case of more than 52 except kogi. also, states like kano, kaduna, plateau, oyo, ogun, ondo, edo delta, river lagos, and the federal capital territory each had more than 1000 recorded cases. the variability in the monthly pattern of covid-19 that can be observed from 3,5,7,9, 11 and 13 was how clustered the covid-19 cases are. in march, the first cluster was observed where states around lagos had high recorded cases (figure 3). the cluster that stood out in april, may, and june was that of kano state and the state around it. by july and august, more cases have been recorded in most states, thus resulting in a smaller number of states forming a cluster. studies of wang et al. (2021); kim & castro (2020), and xie et al. (2020) also observed spatial clustering about covid-19 distribution at a national scale. 47 ifeyinwa sarah obuekwe et al. / geosfera indonesia 6 (1), 2021, 40-54 figure 3. covid 19 recorded cases-march figure 4. spatial autocorrelation by distance-march figure 5. covid 19 recorded cases-april figure 6. spatial autocorrelation by distance-april ifeyinwa sarah obuekwe et al. / geosfera indonesia 6 (1), 2021, 40-54 48 ifeyinwa sarah obuekwe et al. / geosfera indonesia 6 (1), 2021, 40-54 figure 7. covid 19 recorded cases-may figure 8. spatial autocorrelation by distance-may figure 9. covid 19 recorded cases-june figure 10. spatial autocorrelation by distance-june ifeyinwa sarah obuekwe et al. / geosfera indonesia 6 (1), 2021, 40-54 49 ifeyinwa sarah obuekwe et al. / geosfera indonesia 6 (1), 2021, 40-54 figure 11. covid 19 recorded cases-july figure 12. spatial autocorrelation by distance-july figure 13. covid 19 recorded cases-august figure 14. spatial autocorrelation by distance-august figure 13. covid 19 recorded cases-august figure 14. spatial autocorrelation by distance-august ifeyinwa sarah obuekwe et al. / geosfera indonesia 6 (1), 2021, 40-54 50 ifeyinwa sarah obuekwe et al. / geosfera indonesia 6 (1), 2021, 40-54 figure 15. mean distance of nigeria state capitals and the federal capital to other states capital and federal capital with peak category 0 100000 200000 300000 400000 500000 600000 700000 800000 900000 m e a n d is ta n c e i n m e te r state capital and fct with peak category ifeyinwa sarah obuekwe et al. / geosfera indonesia 6 (1), 2021, 40-54 despite more visible clustering, the trend in the clustering of the covid-19 over distance shows no significant peak from march to june (figures 4, 6, 8, and 10). however, that of july and august exhibited patterns with two statistically significant peaks (figure 12 and figure 14). the first and second peak of july were 301,338.39 meter (z score =2.098; p<0.036) and 365,947.83 meter (z score = 2.299; p=0.022) respectively while that of august were 301,338.39 meter (z score =1.918; p=0.055) and 336,128.09 meter (z score =2.013; p=0.044) respectively (figure 12 and figure 14). the result shows that the mean distance of july and august's first peak was the same (301,338.39 meter). therefore, the distance where the spatial processes responsible for clustering is the most pronounced was about 301,338.39 meter. also, the second peak of august (336,128.09 meter) was less than that of july (365,947.83 meter). this implies that there was a significant drop in the mean transmission distance between july and august 2020. this was attributed to the fact that the spread has increased among neighboring state as more states recorded a similar range of covid-19 cases. blank et al. (2016) used a similar approach, observed spatial clustering of bacterial canker severity, and showed that disease severity had significant spatial autocorrelation with dominant pattern recognized as clustered. a drop in mean transmission distance throughout foot-and-mouth outbreaks was similarly reported by salje et al. (2016). kiang et al. (2020) also found a significant spatial correlation associated with covid-19 infections in china. each state capital and the federal capital had a mean distance of more than 300,000 meters to other states and federal capital (figure 15). although, only yola, maiduguri, sokoto, and damaturu have a mean distance above 600,000 meters (figure 15). this is because these states are in the far north of the country, bordering the niger republic. also, each of the state and the federal capital had a mean distance that is above the first and second peak of july and august except for lokoja that has a mean distance (361,924 meters) that was less than the second peak of july (365,947.83 meters) (figure 15). this implies that the interstate lockdown placed to curb the spread of covid-19 was justifiable as any movement within the minimum and maximum significant peak distance can fast-track the spread of covid-19. this corresponds with salje et al. (2016) 's assertion, who claimed that a fundamental property of infectious disease dispersal is the average spatial distance between transmission-linked cases. although this study does not compare covid-19 spread with population density nor socioeconomic activities. however, covid-19 cases have been clustered around two states in nigeria (kano and lagos). moreover, this cannot be farfetched from the fact that kano and lagos happen to be the most populous states in nigeria with vibrant industrial and 51 ifeyinwa sarah obuekwe et al. / geosfera indonesia 6 (1), 2021, 40-54 122 ifeyinwa sarah obuekwe et al. / geosfera indonesia 6 (1), 2021, 40-54 commercial activities. rapone (2020); rocklöv & sjödin (2020) also pointed out that high population density and socioeconomic status are essential drivers of the spread of covid-19. the disbelief regarding the presence of the virus also results in people taking preventive measures lightly. even six months after the first case of coronavirus was reported in nigeria, many nigerians still doubt its existence (csr-in-action, 2020). negligence could be detrimental to the spread to other states. kiang et al. (2020) also reported that people with a history of travel in epidemic areas fail to isolate themselves on time, thus accelerating transmission risk. thus, a study of this capacity that was able to showcase the significance of the temporal dynamics of covid-19 can help guide decision-making regarding how a movement should be restricted to reduce the clustering phenomenon observed across nigeria. 4. conclusion this study has shown that the point location of each state capital in nigeria and recorded cases for each of the 36 nigeria states and the federal capital territory, abuja displayed the significance of temporal dynamics in the mean transmission distance of recorded covid-19 cases in nigeria. this indicates that progression in the spread of the virus increased the spatial coverage of the virus while the distance of risk of exposure decreased. this information could be utilized to establish maximum movement restrictions to contain the spread of covid-19 through lockdown as implemented by the nigeria government. this method can also be applied to well-detailed data and a small proportion of adequately collected data. conflicts of interest the authors declare no conflict of interest. references alkhamis, m. a., al youha, s., khajah, m. m., ben haider, n., alhardan, s., nabeel, a., … al-sabah, s. k. (2020). spatiotemporal dynamics of the covid-19 pandemic in the state of kuwait. international journal of infectious diseases, 98(c), 153–160. https://doi.org/10.1016/j.ijid.2020.06.078. blank, l., cohen, y., borenstein, m., shulhani, r., lofthouse, m., sofer, m., & shtienberg, d. (2016). variables associated with severity of bacterial canker and wilt caused by clavibacter michiganensis subsp. michiganensis in tomato greenhouses. phytopathology, 106(3), 254–261. https://doi.org/10.1094/phyto-07-15-0159-r. 52 https://doi.org/10.1016/j.ijid.2020.06.078 https://doi.org/10.1094/phyto-07-15-0159-r 123 ifeyinwa sarah obuekwe et al. / geosfera indonesia 6 (1), 2021, 40-54 csr-in-action. (2020). the covid-19 disbelief amongst the nigerian citizenry. retrieved from https://www.csr-in-action.org/the-covid-19-disbelief-amongst-the-nigerian citizenry/. dhama, k., khan, s., tiwari, r., sircar, s., bhat, s., malik, y. s., ... & rodriguez-morales, a. j. (2020). coronavirus disease 2019–covid-19. clinical microbiology reviews, 33(4). https://doi.org/10.1128/cmr.00028-20. gayawan, e., awe, o., oseni, b., uzochukwu, i., adekunle, a., samuel, g., … adegboye, o. (2020). the spatio-temporal epidemic dynamics of covid-19 outbreak in africa. epidemiology and infection. https://doi.org/10.1101/2020.04.21.20074435. gis laboratory geography department. (2020). map of nigeria. kano : bayero university. kiang, m., chin, e., huynh, b., chapman, l., rodríguez-barraquer, i., greenhouse, b., … lo, n. (2020). routine asymptomatic testing strategies for airline travel during the covid-19 pandemic: a simulation analysis. the lancet infectious diseases. https://doi.org/10.1101/2020.12.08.20246132. kim, s., & castro, m. c. (2020). spatiotemporal pattern of covid-19 and government response in south korea (as of may 31, 2020). international journal of infectious diseases, 98(c), 328–333. https://doi.org/10.1016/j.ijid.2020.07.004. kuwait government online. (2020) covid-19 updates, state of kuwait. retrieved from https://e.gov.kw/sites/kgoarabic/pages/homepage.aspx. marziano, v., pugliese, a., merler, s., & ajelli, m. (2017). detecting a surprisingly low transmission distance in the early phase of the 2009 influenza pandemic. scientific reports, 7(1), 1–9. https://doi.org/10.1038/s41598-017-12415-2. mckee, m., & stuckler, d. (2020). if the world fails to protect the economy, covid-19 will damage health not just now but also in the future. nature medicine, 26(5), 640–642. https://doi.org/10.1038/s41591-020-0863-y. memish, z. a., cotten, m., meyer, b., watson, s. j., alsahafi, a. j., al rabeeah, a. a., … drosten, c. (2014). human infection with mers coronavirus after exposure to infected camels, saudi arabia, 2013. emerging infectious diseases, 20(6), 1012– 1015. https://doi.org/10.3201/eid2006.140402. moran, p. a. (1948). the interpretation of statistical maps. journal of the royal statistical society: series b (methodological), 10(2), 243-251. murray, c. j. (2020). forecasting covid-19 impact on hospital bed-days, icu-days, ventilator-days and deaths by us state in the next 4 months. medrxiv. https://doi.org/10.1101/2020.03.27.20043752. national bureau of statistics (2011). annual abstract of statistics. abuja : national bureau of statistics. nigeria centre for disease control (2020). covid-19 data. retrieved from https://covid19.ncdc.gov.ng/. 53 https://www.csr-in-action.org/the-covid-19-disbelief-amongst-the-nigerian%20citizenry/ https://www.csr-in-action.org/the-covid-19-disbelief-amongst-the-nigerian%20citizenry/ https://doi.org/10.1128/cmr.00028-20 https://doi.org/10.1101/2020.04.21.20074435 https://doi.org/10.1101/2020.12.08.20246132 https://doi.org/10.1016/j.ijid.2020.07.004 https://e.gov.kw/sites/kgoarabic/pages/homepage.aspx https://doi.org/10.1038/s41598-017-12415-2 https://doi.org/10.1038/s41591-020-0863-y https://doi.org/10.3201/eid2006.140402 https://rss.onlinelibrary.wiley.com/doi/abs/10.1111/j.2517-6161.1948.tb00012.x https://rss.onlinelibrary.wiley.com/doi/abs/10.1111/j.2517-6161.1948.tb00012.x https://doi.org/10.1101/2020.03.27.20043752 https://nigerianstat.gov.ng/pdfuploads/annual_abstract_of_statistics_2011.pdf https://nigerianstat.gov.ng/pdfuploads/annual_abstract_of_statistics_2011.pdf https://covid19.ncdc.gov.ng/ 124 ifeyinwa sarah obuekwe et al. / geosfera indonesia 6 (1), 2021, 40-54 okunade, s. k., & ogunnubi, o. (2019). the african union protocol on free movement: a panacea to end border porosity? journal of african union studies, 8(1), 73–91. https://doi.org/10.31920/2050-4306/2019/v8n1a4. prem, k., liu, y., russell, t. w., kucharski, a. j., eggo, r. m., davies, n., … klepac, p. (2020). the effect of control strategies to reduce social mixing on outcomes of the covid-19 epidemic in wuhan, china: a modelling study. the lancet. public health, 5(5), e261–e270. https://doi.org/10.1016/s2468-2667(20)30073-6. rapone, c. (2020); migrant workers and the covid 19 pandemic. united nations food and agriculture organization. retrieved from http://www.fao.org/documents/card/en/c/ca8559en/. rocklöv, j., & sjödin, h. (2020). high population densities catalyze the spread of covid19. journal of travel medicine. https://doi.org/10.1093/jtm/taaa038/5807719. salje, h., cummings, d. a. t., & lessler, j. (2016). estimating infectious disease transmission distances using the overall distribution of cases. epidemics, 17(c), 10–18. https://doi.org/10.1016/j.epidem.2016.10.001. scarpone, c., brinkmann, s. t., große, t., sonnenwald, d., fuchs, m., & walker, b. b. (2020). a multimethod approach for county-scale geospatial analysis of emerging infectious diseases: a cross-sectional case study of covid-19 incidence in germany. international journal of health geographics, 19(1), 1–17. https://doi.org/10.1186/s12942-020-00225-1. teachout, m., & zipel, c., (2020). the economic impact of covid-19 lockdowns in subsaharan africa. retrieved from https://www.theigc.org/wpcontent/uploads/2020/05/teachout-and-zipfel-2020-policy-brief-.pdf. wang, y., liu, y., struthers, j., & lian, m. (2021). spatiotemporal characteristics of the covid-19 epidemic in the united states. clinical infectious diseases, 72(4), 643– 651. https://doi.org/10.1093/cid/ciaa934. woodhill, j (2020). responding to the impact of covid-19 on rural people and food systems. retrieved from https://www.foresight4food.net/wp-content/uploads/2020/05/impactof-covid-19-on-rural-poverty-and-food-systems-v2.pdf. worldometer (2020). nigeria population. retrieved from https://www.worldometers.info/world-population/nigeria-population/. xie, z., qin, y., li, y., shen, w., zheng, z., & liu, s. (2020). spatial and temporal differentiation of covid-19 epidemic spread in mainland china and its influencing factors. science of the total environment, 744(c), 140929. https://doi.org/10.1016/j.scitotenv.2020.140929. yang, f., pahlavan, a. a., mendez, s., abkarian, m., & stone, h. a. (2020). towards improved social distancing guidelines: space and time dependence of virus transmission from speech-driven aerosol transport between two individuals. physical review fluids, 5(12). https://doi.org/10.1103/physrevfluids.5.122501. 54 https://doi.org/10.31920/2050-4306/2019/v8n1a4 https://doi.org/10.1016/s2468-2667(20)30073-6 http://www.fao.org/documents/card/en/c/ca8559en/ https://doi.org/10.1093/jtm/taaa038/5807719 https://doi.org/10.1016/j.epidem.2016.10.001 https://doi.org/10.1186/s12942-020-00225-1 https://www.theigc.org/wp-content/uploads/2020/05/teachout-and-zipfel-2020-policy-brief-.pdf https://www.theigc.org/wp-content/uploads/2020/05/teachout-and-zipfel-2020-policy-brief-.pdf https://doi.org/10.1093/cid/ciaa934 https://www.worldometers.info/world-population/nigeria-population/ https://doi.org/10.1016/j.scitotenv.2020.140929 https://doi.org/10.1103/physrevfluids.5.122501 richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 124 an assessment of the various mitigation strategies to combat desertification in jibia and kaita local government areas of katsina state richard sunday thlakma1*and omale eche john2 1department of geography, faculty of humanities, management and social sciences, federal university of kashere, pmb 0182, gombe state, nigeria 2department of geography, ahmadu bello university zaria, nigeria email: profsrthlakma@gmail.com received 7 april 2019/ revised 19 july 2019/ accepted 22 july 2019/ published 2 august 2019 abstract this study was conducted on an assessment of the various mitigation strategies to combat desertification in jibia and kaita local government areas of katsina state, nigeria. the data use includes satellite imageries for the study such as landsat mss of 1976, landsat tm of 1987, spot xs of 1995 and landsat etm of 2006 as well as structured questionnaires. sixty close ended copies of the questionnaire were administered in the study. purposive sampling method of administering questionnaires was adopted. the percentages land mass covered for each of these variables was determined and estimated in m2. literature was obtained from various agencies which were responsible for desertification control in katsina state. it was found from the reserved forest that in 1976 the percentage of reserved forest was 2.57%. in 1987 however, it increased by 73.9% to 76.47 %. by 1995, it declined by 9.42% to 67.05% and further declined by 0.52% in 2006. effort to combat desertification through the use of reserved forest has been quite significant over the years. also, noticed was a declined in shelter belt from 5.91% in 1987 to 1.097% in 1995 and a shot up to 7.39% in 2006. about 37% of the respondent opined that the deforestation leads to the disappearance of trees while 33% pinioned that it leads to reduction on agricultural productivity. the major strategy adopted to combat desertification is tree planting as supported by 88% of the respondents. it found that desertification as major environmental problem of the study area has reduced drastically from 43.34% in 1976 to 1.29% in 2006. it was also revealed from this study that some organizations such as european economic community/katsina state government eec/ktsg, katsina afforestation project unit ktapu and local government councils are the major agencies that are responsible for mitigating desertification in the study area. keywords: desertification, mitigation, afforestation, shelterbelt and satellite image 1. introduction campbell (1986) and mortimore (1989) define desertification as a process of sustained land degradation (loss of primary production) that results in the inability of the environment to sustain the demands being made upon it by socio – economic systems at geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.4 no. 2 (2019), 124-145, august, 2019 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v4i2.10192 richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 125 existing levels of technology and economic development and under prevailing climatic conditions especially drought. this definition reflects the situation in jibia and kaita local government areas of katsina state which is the study area in which the poor socio-economic activities led the residents to engaged in deforestation which led to the increase in deforestation and drought and also led to increase in micro climate of the study area leading to thereby increasing the rate and magnitudes of deforestation in the jibia and kaita local government areas. deforestation and the degradation of other vegetation, particularly near the margins of deserts have caused once fertile, vegetated land to become barren in a process called desertification. it has been suggested that desertification should be regarded as an extreme form of land degradation occurring where vegetation cover falls below 35 percent on a long term basis (binns 1990). although desert boundaries have shifted over time, deserts have always characterized the earth’s subtropical zones. global patterns of air circulation dictates that the subtropics are regions of subsiding air. when air subsides, it cools down and its capacity to hold moisture decreases, so inhibiting the formation of rain. this accounts for a prevalence of dry climates between latitudes 15o and 30o ‘north and south of the equator. however, these dry climates are extended into other latitudes and their patterns complicated by additional factors, such as distance from the rain-supplying oceans, seasonal high-pressure zones of large continental areas linked with monsoon systems, or the presence of mountain barriers over which air spills on the leeward side. thus creating rain shadows, (united nations conference on desertification nairobi, 1977). the first alarm on the south ward movement of the sahara desert into nigeria was raised by stebbing in (1935) partly in response to other environmental deterioration and desert encroachment. an anglo-french forestry commission in 1937 investigated the evidence of desertification in the northern part of nigeria, and found no evidence to support the report. however, this report created some concern in the colonial emirate. they embarked on tree planting to stop the southward drift of sahara desert, as far back as the 1940s. generally, areas most severely affected by desertification in nigeria are the semi-arid areas lying roughly north of latitude 12on, and these fall within the sudan and sahel zones of nigeria (sagua, et al, 1987). the extent and severity of desertification in nigeria is not fully established neither is the rate of its progression properly documented. however, it is generally agreed that it is by far the most pressing richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 126 environmental problem in the northern part of the country. the visible sign of the phenomenon is the gradual shift in vegetation from bushes and occasional trees to grass and bushes and in the final stages, expansive areas of desert like sand (ariyo, et al 2005). the united nation conventions to combat desertification has called for actions involving international cooperation and a partnership approach. it focuses on improving land productivity, the application of land conservation and sustainable management and water resources, (undpi, 1997). according to the federal government of nigeria (fos, 1999) estimates, between 50% and 75% of bauchi, borno, gombe, jigawa, kano, katsina, kebbi, sokoto, yobe, and zamfara states are being affected by desertification. these states, with a population of about 35 million people account for about 35% of the country’s total land area. table 1. spread of desertification in nigeria (fos, 1999). land area (km2) % of nigeria landmass affected bauchi/gombe 64,605 6.99 borno 70,890 7.67 yobe 45,502 4.93 kano 20,131 2.18 jagawa 23,154 2.51 katsina 24,192 2.62 sokoto/zamfara 65,735 7.12 kebbi 36,800 3.98 in addition, seven adjacent states to the south are reported to have about 10% to 15% of their land areas threatened by processes of desertification. it is estimated that the country is currently losing about 351,000 hectares of its landmass to desert conditions annually, and such conditions are estimated to be advancing south wards at the rate of about 0.6km per year (ariyo et al 2005). in the absence of concrete remedial and mitigative measures, it is estimated that the total cost of environmental degradation in nigeria would amount to about u.s. $5.110 billion per annum, 73% of which will result from land degradation alone (including desertification and erosion (ariyo et al., 2005). njeru, (2009) reported that sand dune stabilization is often done through the use of shelterbelt, woodlot and wind breaks. wind breaks are made from trees and bushes and are used to reduce water erosion and evapotranspiration. they were widely encouraged by development agencies from the middle east. also, the spraying of petroleum and nano clay over semi-arid crop land. this is often done in areas where richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 127 either petroleum or nano clay obtainable for example in iran. in both cases the application of the materials coats seedlings to prevent moisture loss and prevent them from being blown away. community participation in controlling desertification is also encouraged by the united nation convention to combat desertification which calls for a bottom up participatory approach in identifying, implementing, monitoring and evaluating projects that combat desertification and mitigate the effect of drought. project should be initiated and managed with maximum participation of local communities including women, youth, poor farmers, and pastoralists. the unccd offers local communities a very wide range of opportunities based on local communities, local circumstances, tradition, culture, norms, knowledge,and aspiration, (msafirri, 2009). katsina state is one of the states affected by desertification. it has both environmental and socio economic consequences. according to ktarda (2006). all the farmlands within kwangwalam area of katsina state are severely subjected to strong northeasterly harmattan wind, and sheet erosion, which sweeps the top soils, leaving the land bare and unproductive for agricultural purposes. murtala (2003) reported that desertification in katsina state has led to the reduction in the productivity of the land to the bearest minimum, thus eliminating the already meagre food and water resources for livestock. bala (2003) reports that katsina state has many desertification control projects.these include eec/ktsg, katsina arid zone programme, fgn/world bank assisted afforestation project, katsina state committee on drought and desertification control, federal department of forestry, katsina state ministry of agriculture, and katsina state afforestation project unit, ktpu. their major aim is afforestation, and land management to combat the menace of desertification. despite global concern about desertification and other forms of land degradation (soil quality decline, huge acres of land lost due to soil erosion, fertile soils erode away, overgrazing by animals such as cattle, goats, sheep, feed on the grass amongst others) and many years of efforts and investment made for prevention, cure or rehabilitation, the processes of land degradation persist. there are a variety of existing and potential prevention and mitigation strategies for the various desertification and land degradation process, such as physical measures and adaptation strategies integrating changing social, economic, institutional and policy factors. the mitigation of water-related land degradation is crucial in arid and semi-arid areas which are very prone to desertification richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 128 and successful measures invariably depend on an improvement of water storage in the soil (njeru, 2005). an appraisal of desertification strategies is important for the purpose of desert management in katsina state and other parts of nigeria. it is on this background the research aimed at assessment of the various mitigation strategies to combat desertification in jibia and kaita local government areas of katsina state by identify the various mitigation strategies employed in the lgas and assessing the degree of success of the mitigation strategies adopted for mitigating the desertification problem in the lgas. the study area covers jibia and kaita local government areas. these local government areas are located adjacent to each other. they are located approximately between latitudes 12,045n and 13,015n and longitudes 7,000e and 80,30e. the area is located in the extreme north western part of katsina state as show in figure 1. figure 1. map of the study area the climate is seasonally wet and dry. it is dominated by two air masses. these are the rain bearing south-westerly winds and the cold, dry and dusty north-easterly winds, locally known as the “harmattan.” at different times of the year, when one or the other winds prevails, the area experiences either rainfall or dry harmattan depending on the advance or retreat of the other (nyong and kanarogou, 1999). the vegetation here is sudan savannah type.it it is composed of trees scattered over an expanse of grassland. the trees are usually characterized by broad canopies e.g the baobab with large trunk.it is taller and larger than the others species or types found here.it also includes various types of acacias (nilofica, albida and seyal). others are richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 128 and successful measures invariably depend on an improvement of water storage in the soil (njeru, 2005). an appraisal of desertification strategies is important for the purpose of desert management in katsina state and other parts of nigeria. it is on this background the research aimed at assessment of the various mitigation strategies to combat desertification in jibia and kaita local government areas of katsina state by identify the various mitigation strategies employed in the lgas and assessing the degree of success of the mitigation strategies adopted for mitigating the desertification problem in the lgas. the study area covers jibia and kaita local government areas. these local government areas are located adjacent to each other. they are located approximately between latitudes 12,045n and 13,015n and longitudes 7,000e and 80,30e. the area is located in the extreme north western part of katsina state as show in figure 1. figure 1. map of the study area the climate is seasonally wet and dry. it is dominated by two air masses. these are the rain bearing south-westerly winds and the cold, dry and dusty north-easterly winds, locally known as the “harmattan.” at different times of the year, when one or the other winds prevails, the area experiences either rainfall or dry harmattan depending on the advance or retreat of the other (nyong and kanarogou, 1999). the vegetation here is sudan savannah type.it it is composed of trees scattered over an expanse of grassland. the trees are usually characterized by broad canopies e.g the baobab with large trunk.it is taller and larger than the others species or types found here.it also includes various types of acacias (nilofica, albida and seyal). others are richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 128 and successful measures invariably depend on an improvement of water storage in the soil (njeru, 2005). an appraisal of desertification strategies is important for the purpose of desert management in katsina state and other parts of nigeria. it is on this background the research aimed at assessment of the various mitigation strategies to combat desertification in jibia and kaita local government areas of katsina state by identify the various mitigation strategies employed in the lgas and assessing the degree of success of the mitigation strategies adopted for mitigating the desertification problem in the lgas. the study area covers jibia and kaita local government areas. these local government areas are located adjacent to each other. they are located approximately between latitudes 12,045n and 13,015n and longitudes 7,000e and 80,30e. the area is located in the extreme north western part of katsina state as show in figure 1. figure 1. map of the study area the climate is seasonally wet and dry. it is dominated by two air masses. these are the rain bearing south-westerly winds and the cold, dry and dusty north-easterly winds, locally known as the “harmattan.” at different times of the year, when one or the other winds prevails, the area experiences either rainfall or dry harmattan depending on the advance or retreat of the other (nyong and kanarogou, 1999). the vegetation here is sudan savannah type.it it is composed of trees scattered over an expanse of grassland. the trees are usually characterized by broad canopies e.g the baobab with large trunk.it is taller and larger than the others species or types found here.it also includes various types of acacias (nilofica, albida and seyal). others are richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 129 neem (azadrita indica) etc and various types of scattered shrubs such as plastima cassia sigrana, occasionally forming woodlot. most of these trees are xylophytic in nature i.e the ability to resist drought conditions, this is through having longroots, leathery leaves and tiny leaves, as well as development of spines to reduce excessive transpiration. the drought resistant plants do not shed their leaves, but other trees shed their leaves during the dry season. the blades of the grasses wither and dry off during the dry season. their underground stems develop new roots during wet season. grasses in the area hardly grows up to 1m at maturity. pasture in the area is very low and grazing fields are diminishing due to intensive cultivation by the growing population and shrubs usually dry off in the dry season leaving the soil bare, man-made plantations forms a significant portion of vegetation in this area. shelter belts woodlots and wind breaks are all found in the area (shittu, 1999). the study area falls within the chad formation which is made up of sedimentary rocks of cretaceous origin. the relief of the area is of the lower chad plains. the relative relief falls within the average of about 15 to 20 metres, the landform in the study area is sandy plains where great sand sheets occupy most of the area. however, it is not uncommon to find deposits of sand dunes of varying degrees especially when you move towards daddara kusa, kaga villages in jibia local government area and dankama, duma, jiki gisgerewa villages in kaita local government area northwards. the dunes are formed from the deposition of eroded materials carried along by strong winds from across the sahara desert, especially during the dry season, (shittu, 1999). the soil consists of mostly unconsolidated sediments which are predominantly sandy, silt to sandy loam, it is brown or reddish brown in nature. this type of soil is formed from the deposition of eroded materials over sedimentary formation. they are less acidic and well drained, with fairly low clay content. jibia local government area has a population of 167,435 people, while kaita local government area has a population of 182,405(national population commission 2006). the people of jibia and kaita local government areas are predominantly hausa and fulani living together, majority of the inhabitants of the areas are farmers, (subsistence). they also keep animals; almost every family keeps grazing animals like cattle, goats, and sheep. these are usually moved by herders from one place to the other in search of pastures especially during the dry season. some owners of these animals richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 130 move then to areas south of katsina state especially the middle belt region of the country during the dry season in search of past. 2. the methods identify the various mitigation strategies adopted to curb desertification in the study area. this was determined from the satellite imageries, landsat mss of 1976, 50m, landsat tm 30m of 1987, 1995 spot xs20m and 2006 landsat etm. these imageries also covered four decades with one for each decade. the percentages land mass covered for each of these variables was determined and estimated in m2. the imageries used to achieve these objectives, where analyzed by visual interpretation of the imageries. digital image processing of the satellite data and analysis of the stated objectives of the study were carried out using the basic software’s. earth resource data acquisition system, arcgis 10.0 software. these digital data on cd roms were procured from federal department of agriculture and land resources, livestock house mando, in kaduna and the national space research and development agency, abuja. assessing the degree of success for mitigation strategies adopted for mitigating the desertification problem in the lgas. this was determined from structured questionnaire, which was administered to respondents. sixty close ended copies of the questionnaire were administered in the study. purposive sampling method of administering questionnaires was adopted. in addition to the data obtained from the satellite imageries and questionnaire administered, literature was also obtained from various agencies which were responsible for desertification control in katsina state. some of the agencies are european economic community eec/katsina state government (eec/ktgs), katsina state agricultural and rural development authority (ktarda and the afforestation project unit (ktapu). descriptive statistics such as tables, mean, graphs, percentages, frequency, pie chart, bar graphs and line graphs were used for data analysis and presentation. 3. results and discussion 3.1 identify the various strategies adopted to combat desertification available statistics show that the strategies used to combat desertification in the study areas are: through reserved forests, reservoirs for irrigation purposes in other to richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 131 maintain and sustain the soil moisture contents so as to reduced decline in soil fertility, tree planting in the form of shelter belts, woodlots, trees on boundary, the use of vertiver grasses, natural tree regeneration, community and private woodlots (i.e. wind breaker). from the satellite imagery, the estimated land mass (in meter square) was estimated for each of the strategies in four decades: 1976, 1987, 1995 and 2006. percentages and line graphs were then used to analyse the data. the data extracted are presented in table 2. 0 20 40 60 80 100 1970 1980 1990 2000 2010 pe rc en ta g e year rf rf figure 3. trend of reserved forest area in the study area (1976 – 2006) source: author’s analysis richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 132 table 2. afforestation statistics in jibia and kaita lga year reserved forest (rf) in m2 rf (%) reservoir (r) in m2 r (%) tree planting e.g woodlots, natural regeneration, trees on farmland (tp) in m2 tp (%) shelter belt (sb) in m2 sb (%) afforestation total total 1976 1276564.019867 2.57 48331705.96 97.43 49608269.88 100.0 1987 164925844.03604 76.48 49446684.16 22.93 1276564.02 5.91 215649092.2 100.0 1995 193411475.14774 67.05 23312072.56 8.08 68566593.32 23.77 3164720.65 1.10 288454861.6 100.0 2006 199901900.712514 66.54 22958856.09 7.64 75342483.75 25.08 2220605.66 7.39 300423846.2sssssss 100.0 source: author’s analysis richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 133 3.1.1 forest reserve it was found from the reserved forest that in 1976 the percentage of reserved forest was 2.57%. in 1987 however, it increased by 73.9% to 76.47 %. by 1995, it declined by 9.42% to 67.05%. by 2006 it further declined by 0.52%. the decline in forest reserve is small compared to the much increase observed. effort to combat desertification through the use of reserved forest has been quite significant over the years. the line graph, showing the trend of reserved forest from 1976 to 2006 (in decades) is shown above. these changes are seen on figures 3, 4, 5 and 6, this is found in the coloration and sizes of the area coverage of the forest reserve areas, shown on the map, it is from these maps that the statistic for the area coverage of reserved forest where determined. 3.1.2 the use of reservoirs for irrigation purposes the result for reservoirs for irrigation also revealed that it declined in size due to decrease in irrigation farming, high level of deforestation, overgrazing by animals, over cultivation of lands for agricultural purposes and increase in climate change in the study area between 1995 and 2006 by 0.44%. the decline in the area coverage of water bodies (jibia dam in particular) between 1995-2006 was as a result of various purposes, the dam is used for e.g domestic purposes. the shrinking size also is attributable to the building up of sediments in the dam. vegetation is also gradually taking over the immediate surrounding of the dam, thereby reducing its size, the shrinking size of the dam may also be attributed to the amount of rainfall, of the particular year the imagery was taken, the amount of rainfall may be small. the dam however has played a very vital role in the irrigation of the vegetation of its immediate surroundings. this has helped to reduce desertification in the area drastically. figures 5 and 6 shows the dam with a little decrease in the area coverage of the dam, in plates 1 and 2 are different views of the dam which is used for irrigation purposes and also supply water for shelter belts, woodlots, etc. figure 7 shows a decrease in the area coverage of the dam. richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 134 figure 3. afforestation in jibia and kaita local government areas of katsina state (1976) figure 4. afforestation in jabia and kaita lga of kastina state (1987) richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 134 figure 3. afforestation in jibia and kaita local government areas of katsina state (1976) figure 4. afforestation in jabia and kaita lga of kastina state (1987) richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 134 figure 3. afforestation in jibia and kaita local government areas of katsina state (1976) figure 4. afforestation in jabia and kaita lga of kastina state (1987) richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 135 figure 5. afforestation in jabia and kaita lga of kastina state (1995) figure 6. afforestation in jabia and kaita lga of kastina state (2006) richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 135 figure 5. afforestation in jabia and kaita lga of kastina state (1995) figure 6. afforestation in jabia and kaita lga of kastina state (2006) richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 135 figure 5. afforestation in jabia and kaita lga of kastina state (1995) figure 6. afforestation in jabia and kaita lga of kastina state (2006) richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 136 7.4 7.6 7.8 8 8.2 1 2 pe rce nta ge decades 1995 and 2006 r r figure 7. reservoir area. 1995 and 2006 plate 1. different views of jibia dam which is used for irrigation in jibia plate 2. different views of jibia dam which is used for irrigation in jibia 3.1.3 shelter belts the total afforestation area reserved as shelter belt or wind breaker in the study area is small. it declines from 5.91% in 1987 to 1.097% in 1995 however, a shot up to 7.39% in 2006 as it shows in figure 8, the drop in the area coverage of shelter belt in the second decade result from poor maintenance and human interference. figure 8: shelter belt area.1987, 1995 and 2006 this evidence is also shown on the vegetal map, of the study area in figures 4, 5 and 6. figure 3 has no shelter belts on it, this is because shelter belts were not established in the sb(%) 1987 1995 2006 richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 137 first decade of this study. plates 3, 4, 5 and 6, f show evidence of afforestation in the study area. plate 3. grass hedging in kwana shagari in kaita local government area of (evidence of afforestation in the study area) plate 4. grass hedging in gidan saidu buzu in kaita local government area of (evidence of afforestation in the study area). plate 5. afforestation shelter belt in kurya in kaita local government area plate 6. afforestation shelter belt in magama in jibia local government area. 3.1.4 tree planting: woodlots, natural tree regeneration, trees on farmland, trees on farm boundaries etc. richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 138 from the satellite imagery, the data collected to assess tree planting as a strategy to combat desertification shows a decreasing trend in the effort towards tree planting, all through the sampled period. the decline in tree planting may be attributed to poor maintenance of the seedlings to maturity and also human interference and animals browsing. 3.2 determination of the success rate of various strategies used for combating desertification in the study area the third objective of the study is to determine the success rate of the various strategies used in combating desertification in the study area. from the literature, the following strategies were identified: the use of water dams for irrigation purposes, establishment of shelter belts, woodlots, wind breaks, trees on farm lands, natural tree regeneration and the planting of vertiver grasses for sand dune stabilisation. for the study area 60 questionnaires were issued to selected respondents. from the frequency analysis, a 100 percent response rate was recorded. this was because of the interest of the respondents on the issue of desertification. when asked if they knew what desertification was, all the respondents said yes. the frequency table is also shown table 3. table 3. knowledge of the term desertification in the study lgas frequency percent valid percent cumulative percent 60 100.0 100.0 100.0 source: author’s analysis 3.2.1 effects of desertification in the study area they were further asked what effects they would associate with desertification, 33.3% said that it makes productive lands to become unproductive; 10 % said it covers roads with sand; another 10% said it makes agricultural land to become unproductive; yet another 10% said it bring sand to cover their houses, and 36.7% said it leads to the disappearance of trees. the frequency table is shown in table 4. despite the much efforts put in place by various organisations to reduce desertification, there are still some areas where desertification is still a problem as shown in plates 7 and 8. richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 139 plate 7. evidence of desertification in magama, in jibia local government area of katsina state, nigeria. table 4. effects of desertification in the study lgas frequency percentage valid percentage cumulative percentage productive lands become unproductive 20 33.3 33.3 33.3 roads covered by sand 6 10.0 10.0 43.3 poor agricultural productivity 6 10.0 10.0 53.3 bring sand to home 6 10.0 10.0 63.3 trees disappeared 22 36.7 36.7 100.0 total 60 100 100 source: author’s analysis as to whether there are any organizations responsible for the mitigation of desertification in the study areas, all the respondents said yes. the organizations were stated to include: eec, ktapu, local government and state government as displayed in table 5. plate 8. evidence of desertification in dankama, in kaita local government area of katsina state, nigeria. the evidence to prove these are shown on plates 3, 4, display in table 5 and 6 where various organizations that are involves in curbing desertification in ahead their projects on grounds in the study area. richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 140 table 5. organisations involved in mitigating desertification in the study lgas frequency percent valid percent cumulative percent eec 27 45.0 45.0 45.0 state government 2 3.3 33.3 48.3 local government 2 3.3 33.3 51.7 ktapu 29 48.3 48.3 100.0 total 60 100.0 100.0 source: author’s analysis. 3.2.2 strategies for combating desertification on the various strategies adopted to combat desertification, 88.3% said tree planting was the dominant strategy employed e.g woodlots, trees on farmlands and natural tree regeneration. 11.7% said providing shelter belt (another means of tree planting that also serves as wind breaker) was the other strategy employed. the frequency table is shown in table 6. table 6. strategies for combating desertification in the study lgas frequency percent valid percent cumulative percent tree planting e.g woodlots, trees on boundary shelter belt total 53 7 60 88.3 11.7 100.0 88.3 11.7 100.0 88.3 100.0 source: author’s analysis. to determine the success rate of tree planting as a strategy of combating desertification, the respondents were asked to rate the effectiveness of the strategy; 15% said very effective, 50% said effective, 30 percent said fairly effective, while 5% said not effective. the frequency table is presented in table 7. based on this response it can be said that tree planting as a strategy for combating desertification in the study area is effective. there are also efforts been made on the part of the local government, community members to arrest desertification in the study area. some the efforts include: campaigning against tree felling, and by tree planting as well. the frequency table for this response is presented in table 8. richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 141 table 7. effectiveness of the strategies adopted to combat desertification in the study lgas frequency percent valid percent cummulative percent very effective 9 15 15 15 effective 30 50 50 65 fairly effective 18 30 30 95 not effective 3 5 5 100 total 60 100 100 source: author’s analysis table 8. community efforts at combating desertification frequency percent valid percent cummulative percent campaign against 27 45 45 45 tree planting 33 55 55 100 total 60 100 100 source: author’s analysis though results obtained from questionnaires may not be a very empirical judgment in arriving at the results obtained, which says that the strategies adopted for the mitigation of desertification in the study area are effective. the result obtained from the use of questionnaire corroborated with the empirical findings adopted earlier in the first and the second objectives of the study, it shows that desertification as an environmental problem of the study area has reduced drastically from 43.34% in 1976 to 1.29% in 2006. these findings are scientific in nature; it now substantiates the result obtained from the use of questionnaire. personal observation of the researcher, who has lived in study area for close to a decade, also is a proof to substantiate the results obtained from the questionnaires. the observations show that afforestation as a means of curbing desertification, is the major technique adopted in the study area, and it is effective. this evidence is also seen by the various photographs of the projects carried out by various organizations to curb desertification in the study area. from the evidences provided by the satellite imageries used for the research, and the literature review, the results obtained, and personal observations of the researcher, whom has lived in the area on which this research was carried for a decade. it shows that desertification richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 142 as an environmental problem of that region is gradually been phased out totally. this evidence is from various activities put in place to check desertification in this region. there has been an internationally assisted programme from the world bank, katsina arid zone programme which was later called european economic community/katsina state government, (eec/ktsg). agricultural development (ifad). katsina state agricultural and community development project (ksacdp).this are all internationally assisted programmes to combat desertification in katsina state, with the study area inclusive. this evidence also correlated with the (unccd, 1997) which called for international cooperation and a partnership approach in checking desertification. it focuses on improving land productivity, application of land conservation and sustainable management of water resources. the federal government of nigeria also plays a very big role in combating desertification in the study area, through the federal ministry of environment, ecological fund, katsina afforestation project unit/federal government assisted, though ktapu is now funded by the katsina state government. the establishment of the jibia dam which has totally erased desertification on its immediate surroundings are some federal government programmes, currently on ground in katsina state. their major roles are to check desertification. these evidences will support the result gotten in this research that shows that desertification has reduced drastically from about (43.34%) in 1976 to about 1.29% in 2006. all these are efforts put in place by the federal government with the study area inclusive, these programmes have aids in reducing desertification in katsina state drastically. these are practical phenomenon that is observed by the researcher. this relates to the work done by bala (2003), who reported that various agencies have desertification control projects on ground in katsina state. these includes the eec/ktsg, world bank assisted afforestation project. katsina committee on drought and desertification control, katsina afforestation project unit ktapu, katsina state ministry of agriculture etc. their major aim is afforestation and land management to combat the menace of desertification, as an environmental problem. the mitigation strategies used: afforestation is the major mitigation strategy used to combat desertification in the study area. this is done through reserved forests, tree planting in the form of woodlots, natural regeneration, trees on farmland shelter belts establishment, orchards the use of vertiver grasses and trees on farm boundaries. the personal observations of the researcher and the literature reviewed shows that the major mitigation strategies used in the study area by katsina afforestation project unit, (ktapu). katsina agric and rural richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 143 development authority, (ktarda). european economic community / katsina state government,eec/ktsg. adopted afforestation as the major mitigation strategy in checking desertification in the study area. the jibia dam also plays a very important role in checking desertification in the study area. this was supported by findings done by sani (1996). all the evidences given from the results obtained from the research and personal observations of the researcher has justified the findings which said desertification has reduced drastically in the study area. 4. conclusion the assessment of the success of the strategies used in combating desertification in the study area revealed that there has been an appreciable effort put in place to mitigate the effects of desertification. the area coverage of desertification determined from the satellite imageries shows that the spread was much at the first decade of the study, with an area coverage of about 43.34% in 1976 but it shrinked in size overtime to about 1.29% in 2006. afforestation statistics derived from the satellite imageries also shows reserve forest which the area coverage in 1976 was only 2.57% but increased overtime to 66.53% in 2006. the area coverage of shelter belt was 5.91% in 1987 and 7.39 in 2006. with the evidences given, it can now be considered that desertification in the study area has reduced greatly. results obtained from this research, shows that the major strategy for checking desertification in the study area is afforestation and the strategies are effective. this research to some extent has proved such notions not to be totally right, especially the food and agricultural organization (fao) report on desertification in nigeria which shows that desertification is increasing at an alarming rate of about 0.6km into nigeria but in this case it is reducing drastically. references ariyo, j.a, abdullahi, c.j. stigter, o.z onyewotu and i. musa (2005). community participation in planning desertification, control interventions in northern nigeria. lessons from kano state. a paper presented at the conference on prospects and problems of agricultural development in nigeria, held in ahmadu bello university zaria. june 29th – july 2nd, 2005. auwal, u. (2006). an appraisal of desertification in arid zone of bauchi state. unpublished pgdem thesis department of geography, bayero university kano. babura, d.u. (2001). desertifucation in babura local government area. unpublished pgdem thesis. department of geography, bayero university kano. richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 144 bala, a. (2003). an evaluation of drought incidence and hazards in northern nigeria. a paper presented at a seminar on the conservation of the environment. department of geography isa kaita college of education, dutsinma, katsina state 5th november. bins, t. (1990). the threatening deserts: ox blackwell. campbell, d.j (1986). the prospects for desertification in kajiado district kenya, geg. federal office of statistics (1999). annual abstracts of statistics: facts and figures about nigeria. katsina afforestation project unit (2006). a brief on katsina afforestation project unit (fgn assisted) 1st february, 2006. katsina afforestation project unit (2006). annual reports on afforestation projects. katsina afforestation project unit (2009). annual reports on afforestation project. katsina afforestation project unit ktapu. (2009). a brief on katsina afforestation project unit (fgn assited) 5th february, 2009. katsina agricultural and rural development authority ktarda. (2006). land management\ unit, historical background to soil conservation in katsina state. katsina arid zone programme eec/ktsg (1995). soil conservation experience, a paper for ksacdp one day soil conservation strategy workshop 14th december, 1995. katsina arid zone programme eec/ktsg. (1995). historical background of soil conservation efforts in katsina state. msafirri, f. (2009). involving or not involving communities in strategies to combat desertification and drought in kenya. murtala s.k. (2003). an analysis of the problems of desertification in katsina local government area. an nce project, isa kaita college of education dutsin ma, katsina state. nasiru, i.m. (2009). combating desertification and drought in nigeria. daily trust monday, 25th. national population commission (2006). federal republic of nigeria (2009), national population commission official gazette no2, abuja 2nd february 2009 vol 96. njeru, j. (2005). monitoring and modelling crop growth, water use and production crop growth, water use and production under dry land environment, north west of mount kenya. nyong, a.o. and kanoroglou, p.s (1999). the influence of water resources and their locations on rural distribution in north eastern nigeria. a journal of environmental sciences. richard sunday thlakma and omale eche john/geosi vol 4 no 2 (2019) 124-145 145 owen and pickering (1997). global environmental issues. rutledge and new york. sagua, v.o, enabor, e.e, k.o p.r.o, ojanuga a.v, mortimore, m. and kalu, a.e. (1987). ecological disasters in nigeria. drought and desertification federal ministry of science and technology lagos. sani, m. (1996). evaluation of desertification and its effects in jibia local government area of katsina state. unpublished pgdem thesis. department of geography bayero university kano. shittu, k. (1999). an assessment on the socio economic effects of desertification in katsina state. an unpublished bsc project department of geography bayero university kano. stebbing, e.p. (1935). the encroaching sahara: the threat to west africa colonies. a geographical journal. the united nations convention to combat desertification (1997). a new response an age – old problem. united nations conversation on desertification (1977). desertification, it causes and consequences: pergmon press. united nations, department for public information (1997). the united nations convention to combat desertification. whates and jones (1992). land degradation. edward arnold london. 301 research article land cover changes based on cellular automata for land surface temperature in semarang regency fahrudin hanafi1,* , dinda putri rahmadewi1, fajar setiawan2 1department of geography, faculty of social sciences, state university of semarang, sekaran gunungpati, semarang, 50229, indonesia 2limnology research center, indonesian institute of sciences (lipi), bogor, 16911, indonesia received 7 march 2021/revised 17 november 2021/accepted 8 december 2021/published 20 december 2021 abstract land cover changes based on cellular automata for surface temperature in semarang regency has increased significantly due to the continuous rise in its population. therefore, this study aims to identify, analyze and predict multitemporal land cover changes and surface temperature distribution in 2028. data on the land cover map were obtained from landsat 7 and 8 based on supervised classification, while land surface temperature (lst) was calculated from its thermal bands. the collected data were analyzed for accuracy through observation, while cellular automata markov chain was used to predict the associated changes in 2028. the result showed that there are 4 land cover maps with 5-year intervals from 2003 to 2018 at an accuracy of more than 85%. furthermore, the existing land covers were dominated by forest with decreasing trend, while the built-up area continuously increased. the existing land surface temperature range from 20.6°c to 36.6°c, at an average of 28.2°c and a yearly increase of 0.07°c. the temperature changes are positively correlated with the occurrence of land conversion. land cover predictions for 2028 show similar forest dominance, with a 23,4% built-up area at a surface temperature of 28.9°c. keywords: land cover change; cellular automata-markov chain; land surface temperature 1. introduction according to the united nations (2018), population increase is a global problem experienced in every country, with 55% of humans presently living in urban or regional areas, likely increasing by 68% in 2050. these changes tend to affect both local and global climate components, such as the land surface temperature (lst). for example, in nigeria, there was an increase of 19,166.13 ha in urban built areas from 2002 to 2013, with a rise in lst by 6 °c (igun & williams., 2018). geosfera indonesia vol. 6 no. 3, december 2021, 301-318 p-issn 2598-9723, e-issn 2614-8528 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v6i3.23471 *corresponding author. email address : fahrudin.hanafi@mail.unnes.ac.id (fahrudin hanafi) mailto:fahrudin.hanafi@mail.unnes.ac.id 303 fahrudin hanafi et al. / geosfera indonesia 6 (3), 2021, 301-318 khandelwal et al. (2018) stated that an increase in lst tends to disrupt the climateenergy balance, such as the heat wave phenomenon experienced in 7 major european countries, namely the united kingdom (38.1 °c), germany (41.7 °c), belgium (41.8 °c), france (42.6°c), luxembourg (40.8 °c), scotland (31.6 °c), and the netherlands (40.7 °c) recorded in july 2019. in southeast asia, several major cities also experienced similar conditions. an increase in hotspots was 20% greater than the average lst in hanoi (tran et al., 2017) and at a temperature of 2.9 ° c in jakarta which is higher than in bangkok (estoque et al., 2017). land cover changes also occurred in central java province. moreover, 128 ha of rice fields were converted to settlements or used for other purposes from 2009 to 2010 (bps, 2015). on the contrary, the average air temperature in central java province from 2032 to 2040 was predicted to increase within the range of 0.81 to 0.85 ° c (bmkg, 2019). semarang regency, central java province, indonesia, had a high population growth rate (8.74%) from 2010 to 2016 (bps, 2017a). based on statistical data, in 2016, 1.014 million people with a density of 1.081 people/km2, was recorded. this figure is higher compared to the national average population density of 127 people/km2. however, from 2011 to 2016, agricultural areas were reduced by 0.94% from 60,439.96 to 59,872.49 ha, while land used for other purposes was increased by 1.64%, which is equivalent to 35,148.18 ha (bps, 2017b). this indicates that semarang regency is also susceptible to land and climate changes problems, specifically areas adjacent to the city, which has experienced rapid development and recorded an lst average of 1.32 ° c (nugraha et al., 2016). analysis carried out using past and present spatial data is considered one of the requirements for geographic studies (dadras et al., 2015). cellular automata are the commonly used spatial model of land cover change. it is dynamic and composed of interrelated cells with discrete units (wang et al., 2012). cellular automata are used mainly to generate and predict potential changes (tran et al., 2017). fu & weng (2016) stated that temporal disparities of thermal characteristics due to land cover changes and responses need to be carried out comprehensively. one of the environmental parameters analyzed in this study is lst, estimated from the single thermal channel or split window algorithm method, dependent on the number of bands used (pu et al., 2006). both have a weakness in respect to the atmospheric profile uncertainty, which strongly affects the accuracy of the result (li et al., 2013). however, this is anticipated by inputting the atmospheric profile data into the thermal band spectral radian correction made by the usgs (united states of geological surveys) (coll et al., 2010). 304 fahrudin hanafi et al. / geosfera indonesia 6 (3), 2021, 301-318 study carried out on the land cover change in semarang regency is common for land suitability, flood (susanti et al., 2012), landslide, sedimentation (apriliyana, 2015), carbon stock, and spatial planning review (pangi et al., 2017). these studies were specifically related to land and averaged surface temperatures (kalinda & bandi, 2018). therefore, this study aims to model land cover changes based on raster data using cellular automata related to its surface temperatures in the future. in addition, it also intends to (1) analyze the surface temperature distribution and land cover changes of semarang regency in 2003, 2008, 2013, and 2018, (2) evaluate the relationship between land cover changes and lst, and (3) investigate the distribution of land cover for the following 10 years. 2. methods this field survey was conducted in semarang regency, central java province, from april to june 2019. the area was considered due to the record time of the imagery data input. furthermore, simulation data input only requires 2 land cover imageries, the initial and step year. however, for the sake of detailed information, this study used those acquired in 2003 (initial), 2008 (step 1), 2013 (step 2) and 2018 (step 3), which was compared using population growth and space needed, such as the assumption based on consistent population per built area on initial, and each step. the satellite image data used are (1) landsat 7 path/row 120/65 imagery recorded on may 20, 2003; (2) landsat 7 path/row 120/65 imagery recorded on june 18, 2008; (3) landsat 8 path/row 120/65 imagery recorded on june 24, 2013; (4) landsat 8 path/row 120/65 imagery recorded on august 25, 2018. unfortunately, landsat 7 (2008) had some bad qualities due to the sensor stripping. however, usgs provided corrections using past imagery with a similar location. secondary data used to support the population growth analysis were obtained from the (1) population growth and built area of semarang regency from 2008 to 2018, then (2) slope from astergdem radar image data (usgs). road networks, activity centers, and river patterns were obtained from big and spatial planning of semarang regency data and used as constraint input on land cover simulation. sampling calculation refers to the technical guidelines for collecting and processing spatial data from the geospatial information agency (big). meanwhile, the number of sample points for each land cover type is determined using the proportional stratified sampling method, as shown in figure 1. field surveys are carried out to measure the temperature of the land surface and cover the ground check. this analysis was carried out from april to june 2019, synchronized with 305 fahrudin hanafi et al. / geosfera indonesia 6 (3), 2021, 301-318 the imagery record period. it was assumed that the weather condition, sun duration, and intensity are similar to the imagery and survey data. also, the duration (on distribution sample) is customized from 08.00 to 11.00 am to adjust the recorded time of the imagery. figure 1. location and research sample in semarang regency, central java land cover is classified (maximum likelihood) using envi 5.1 and differentiated according to the method proposed by danoedoro (2006) concerning water, forest, shrub, agricultural, open, and built areas. the classification accuracy threshold used is 85%, thereby determining its mapping by comparing the 2018 image with field observations. data from the previous year's image is compared with the temporal interpretation of google earth. accuracy is determined using a confusion matrix involving the consideration of omission and commission. overall, it indicates the probability that a pixel belongs to a certain class and its representation in the field (lillesand et al., 2004). land cover prediction in 2028 was made with selva's version of idrisi software in accordance with the markov chain method based on cellular automata. meanwhile, markov chain is used to analyze 2 land cover data realized in different years, namely past (2008) and 306 fahrudin hanafi et al. / geosfera indonesia 6 (3), 2021, 301-318 actual information (2019). the transition matrix is focused on the change of any land cover to build area using a 3x3 matrix. built area conditions control this change from the forest, agriculture, or open field, asides the opposite. agriculture is changed from the forest, or open field, besides the opposite including build area, etc. lst is estimated by transforming pixel into spectral radian values using usgs equations to correct surface reflection errors and earth curvature. meanwhile, errors due to atmospheric disturbances, specifically in terms of processing images of land surface temperatures, are determined with the equation proposed by coll et al. (2010). it contains parameters that tend to affect lst, including emissivity, transmission, upwelling and downwelling (kalinda & bandi, 2018). the profile is obtained from the atmospheric correction parameter calculator, modeled according to data input's date, time, and location (tran et al., 2017). the corrected spectral radian values are converted to brightness temperatures using the usgs formula for landsat imagery. this is estimated as lst using the equation proposed by artist & carnahan (1982) and amiri et al. (2009). it is also used to determine an accurate brightness temperature of 8-14 чm wave (artis & carnahan, 1982), while this study utilized bands 6 (10.4 to 12.5 чm) and 10 (10.60 to11.19 чm). the analysis technique is used to determine the effect of each land cover type on lst changes by comparing the t-count with the t-table. the t-test is carried out using a simple linear regression equation while the t-table size is calculated with the formula t (a/2, n-2) = t (0.05/2, 116-2) = t (0.025, 114) = 1.98099, based on the following criteria: (1) assuming the significance value is <0.05 and t-count> t-table, it means that there is an impact, and (2) assuming the significance value is > 0.05 and t-count <t-table, meaning there is no impact. 3. results and discussion 3.1 land cover changes image classification performed with the supervised method produces land cover maps for 2003, 2008, 2013 and 2018. confusion matrix analysis on table 1 shows an accuracy of 91.38%, 92.24%, 88.79% and 86.21 %. according to fariz (2016), misclassification is not only influenced by differences in recorded time as well as the misidentification of objects from residential land to the forest because tall trees cover their appearance. the accuracy test results obtained annually exceed 85%, therefore, the data is feasible and needs to be used for further analysis (susanti et al., 2012). 307 fahrudin hanafi et al. / geosfera indonesia 6 (3), 2021, 301-318 table 1. producer and overall accuracies of land cover matrix confusion land cover producer accuracy 2003 2008 2013 2018 water body 100.00% 100.00% 100.00% 100.00% forest 98.31% 98.11% 100.00% 93.33% agriculture 61.90% 60.00% 56.25% 80.95% shrubs 100.00% 88.89% 66.67% 66,67% open field 100.00% 100.00% 100.00% 77.78% built area 91.67% 100.00% 95.45% 92.00% over all accuracy 91.38% 92.24% 88.79% 86.21% the results show that the dominated land covers are forest and agricultural areas because the semarang regency is near mountains and fertile, as shown in figure 2. table 2 shows the increased number of forests recorded in 2013, possible because “sengon" and teak plantations starts with land clearing and an approximately 5 years harvest period (nuroniah & putri, 2013) and 15 to 20 years for teak (pudjiono, 2014). this result also corresponds with the semarang regency data by bps (2017), which reported a critical land decrease of 26.2% in 2013 from the previous year a program on forestry services was held to boost its increase. agricultural areas experienced a significant increase of 75.50% from 2013 to 2018. this pattern is common in rural areas, specifically in reduced forest and open fields, thereby boosting agriculture. the reverse is the case in urban areas such as agricultural lands in the nanjing region. china was converted to developed or built areas with 2.6% in 2009 (wang et al., 2016). table 2. land cover changes in semarang regency in 2003, 2008, 2013 and 2018 land cover years 2003 2008 2013 2018 (ha) (%) (ha) (%) (ha) (%) (ha) (%) forest 52,696 51.7 45,742 44.9 49,183 48.3 39,452 38.7 built area 9,903 9.7 18,293 18.0 18,642 18.3 20,012 19.7 shrubs 19,188 18.8 16,413 16.1 12,469 12.2 15,522 15.2 agricultural 11,415 11.2 9,007 8.8 8,303 8.2 14,572 14.3 waters body 967 0.9 676 0.7 996 1.0 767 0.8 open field 7,665 7.5 11,703 11.5 12,240 12.0 11,509 11.3 amount 101,834 100 101,834 100 101,834 100 101,834 100 308 fahrudin hanafi et al. / geosfera indonesia 6 (3), 2021, 301-318 3.2 land cover simulation 2028 land cover simulation processed with markov chain on cellular automata with population growth as a control. furthermore, increase in population and built areas are linearly correlated to each step year to average growth. therefore, the acquired data serves as an area of increased control when cellular automata are executed. the cell movement is constrained by slope, existent built area, road and river networks. land cover changes are influenced by several attributes, from macro (policy) to micro (regional complex) factors (figure 2). in the regional complex, semarang regency develops and changes the influence of roads, slopes, demographics, and land availability. figure 2. land cover changes in 2003-2018 the road as a driving force for mobility affects the pattern of land development, which extends along with the northern and southern parts of ungaran and tengaran districts, respectively. residents tend to build new settlements at a distance of <250 m from the main road.theslope affects development in the highlands, leading to the clustering of existing built areas. 309 fahrudin hanafi et al. / geosfera indonesia 6 (3), 2021, 301-318 population affects human space requirements. the population density in semarang regency was 889 people per km2 in 2003. however, it increased to 1,081 people per km2 in 2017. this is presumed to influence the changing of forests and agricultural lands into built areas. land availability along with its clearing increased from 2003 to 2013. this condition is also accompanied by a decrease in forests, shrubs and agricultural areas because the emergence of open land availability also promotes increased social facilities. on the land cover simulation proposed by 2028, a decline in forests, shrubs and agricultural fields was recorded in the previous 10 years, except water bodies and built -up areas, as shown in table 3. the spatial distribution shows that the developmental pattern of regions built in 2018 is clustered at the regional and economic centers. this includes east, and west ungaran, bergas, ambarawa, bawen, tengaran, suruh, and kaliwungu districts, as indicated in figure 3. however, a difference of only 284.56 ha was realized in accordance with the conditions of built area development in the same location from 1991 to 2001 (pangi et al., 2017). table 3. land cover changes in semarang regency, 2018 2028 land cover years percent changes 2003 2028 (ha) (%) (ha) (%) (%) forest 39,452 38.7 37,010 36.5 -5.68 built area 20,012 19.7 23,727 23.4 18.78 shrubs 15,522 15.2 14,295 14.1 -7.24 agricultural 14,572 14.3 14,096 13.9 -2.80 waters body 767 0.8 773 0.8 0.00 open field 11,509 11.3 11,498 11.3 0.00 amount 101,834 100 101,834 100 land cover simulation results in 2028 show an increase in built areas, a decrease in forest (6.19%), shrubs (7.90%), agricultural (3.27%), and open fields (0.09%). waters bodies such as the rawa pening lake increased by 0.88% in 2018 due to the influence of agricultural areas and shrubs. similar conditions also occurred from 2001 to 2011 when an increase in agricultural lands (2,905.79 ha)was recorded (apriliyana, 2015). the population and built areain the semarang regency linearly correlate with the equation y = 0.02x + 32.06, where y is the built area and x is the total population, as shown in figure 4. this is also used to determine an estimate of 23,770.62 ha in 2028. moreover, when compared with the predicted area determined by the cellular automata method, the 2 estimations are 43.59 ha or 0.18% deviation. this shows that the results of the cellular automata simulation of land cover and population linear regression do not contradict each other. 310 fahrudin hanafi et al. / geosfera indonesia 6 (3), 2021, 301-318 figure 3. land cover in 2018 and 2028 (modeling using the cellular automata) 2018 existing 2018 simulation 311 fahrudin hanafi et al. / geosfera indonesia 6 (3), 2021, 301-318 figure 4. linear equations for population and built-up area (prediction of built-in area in 2028) 3.3 imagery surface temperature vs survey the field survey led to the fluctuation of lst data every hour from 09:00 to 15:00 for different land covers, as shown in figure 5. this is used to ascertain the response of each land cover type to solar radiation. besides, each has a different response rate, although they generally tend to reach the peak temperature at 13:00. it is clear that the built area has the highest lst, reaching 3.6 ° c, and decreases gradually after 13:00. apart from land cover information, satellite imagery is also used to extract lst. this study produced 4 lst distributive maps in 2003, 2008, 2013 and 2018 (figure 6). meanwhile, when compared with the estimated results of the image from the closest year, a positive relationship was determined with a correlation coefficient (r) of 0.637, coefficient of determination (r2) is 0.45 with a degree of significance <0.005 (significant). according to the r-value, the relationship between lst imagery and field survey is positively correlated (fu & weng, 2016). figure 6 shows the image temperature is high, as well as the field, however, the coefficient is different due to dissimilarities in weather conditions. y = 0.02x + 32.06 15 16 17 18 19 20 21 22 23 24 25 900 950 1000 1050 1100 1150 1200 thousands people t h o u sa n d (a re a ) 311 fahrudin hanafi et al. / geosfera indonesia 6 (3), 2021, 301-318 figure 5. changes in surface temperature on each land cover per hour figure 6. linear graph of lst vs land cover changes 25 27 29 31 33 35 37 09.00 10.00 11.00 12.00 13.00 14.00 15.00 l a n d s u rf a c e t e m p e ra tu re s ° c agriculture shrub built area water body open field forest 19 21 23 25 27 29 31 33 35 37 39 1 9 2 0 2 1 2 2 2 3 2 4 2 5 2 6 2 7 l s t o f s u r v e y ( ° c ) lst of imagery (° c) time 312 fahrudin hanafi et al. / geosfera indonesia 6 (3), 2021, 301-318 3.4 surface temperature changes the results of the lst obtained using satellite imagery shows that the maximum and minimum temperatures reached were 37.6 ° c, and 20.6 ° c, respectively. the average lst and standard deviation values are 28.2 ° c and 3.39 ° c. interestingly, the lst temperature from 2003 to 2018 tended to increase, while a decrease was detected in the data acquired in 2008. the decline in land surface temperature is influenced by low solar radiation of approximately 425.55 watts/m2, accumulated over the years. this is caused by the position of the earth's aphelion to the sun, which usually occurs in june. the australian cold munson phenomenon also affects the deviation, which blows cold and dry air from the indonesian coast. it also causes upwelling followed by a decrease of not less than 3° c in the south java sea, besides this usually occurs from july to august (sukresno et al., 2018). the high-temperature area is regularly experienced in regional centers, as shown in figure 6. this shows that lst is concentrated due to the urbanization influence caused by land cover changes (peng fu, 2016). however, it is different from the phenomenon that occurred in 2008 due to the concentration of newly built areas in bancak district which has varying temperatures, depending on the various types (pal & ziaul, 2017). 3.5 surface temperature vs land cover changes to compare continuous data from lst and land cover changes (ordinal), this study collected whole coverage and point samples using grid size as the location. the lst was generated as positive or negative changes compared to the land cover, which was converted to non-changes data. the results of correlation analysis (figure 7) carried out on the land cover and lst from 2003 to 2018 was used to determine the strong relationship between the coefficient of determination (r2: 0.430) and the correlation coefficient (r: 0.s655) (sarwono, 2006). meanwhile, from the t-test on each land cover, it is evident that agricultural areas, forests, and shrubs have a dominant influence (table 4). 313 fahrudin hanafi et al. / geosfera indonesia 6 (3), 2021, 301-318 figure 7. linear graph lst vs land cover changes data land cover is associated with temperature changes, it is evident that the dominant one is the conversion of forests to agricultural areas with a temperature (averaged area) increase of 0.31 ° c/ha, as shown in figure 8 and table 5. this led to an increase in the number of farmers from 144,369 (2013) to 167,044 (2018) in semarang regency (yuliati, 2018). in addition, this condition was also experienced at the national level from 2000 to 2005, where plantations and agricultural areas were the dominant land cover types that replaced 44% of forests. the increase in average surface temperature of regional lst at the study site was raised to relatively 1.06 ° c with an average increase per decade of 0.7 ° c. lin & yu (2005) classified the lst increase in average surface temperature as being greater than the value obtained in beijing and approximately within a range of 0.25 to 0.31 ° c. based on this approach, it was estimated that the average lst in 2028 is expected to reach 28,9 ° c. figure 8. land surface temperature changes in 2003, 2008, 2013, and 2018 2003 2008 2013 2018 314 fahrudin hanafi et al. / geosfera indonesia 6 (3), 2021, 301-318 table 4. regression of land cover with land surface temperature land cover r 2 t-calculated significance forest 0.511 7.912 0.000 agriculture 0.566 3.021 0.019 open field 0.331 2.537 0.025 shrub 0.433 4.095 0.000 water body 0.078 -0.921 0.379 built area 0.285 2.360 0.033 table 5. land cover area and average area lst land cover area (ha) % area changes (°c) averaged area changes 2003 2018 forest forest 5,825.07 61.41% -0.09 -0.05 agriculture 734.58 7.74% 4.05 0.31 built area 97.83 1.03% 2.78 0.03 open field 123.84 1.31% 2.99 0.04 shrub 279.72 2.95% 2.70 0.08 agriculture agriculture 1.53 0.02% 1.22 0.00 built area 649.08 6.84% 2.62 0.18 open field 26.01 0.27% 1.61 0.00 shrub 754.11 7.95% 1.34 0.11 shrub forest 0.54 0.01% -0.31 0.00 agriculture 137.38 1.45% 2.98 0.04 built area 648.18 6.83% 3.90 0.27 open field 2.97 0.03% 2.86 0.00 shrub 204.89 2.16% 2.53 0.05 amount 9,485.73 100% 1.06 the differences in lst are not only influenced by the land cover type. the results obtained from this study differs from other studies due to regional complexes. this bias is caused by several factors such as solar radiation, topography, soil and vegetative types. the linear regressionshows that the solar radiation value has a positive effect on lst. every 1 watt/m2triggers the average lst area by 0.1 ° c from 2003 to 2018. the topography’s response was slightly different from that of the lst. in addition, its sample distribution shows an inverse comparison. the regression equation is y = -0.001x + 23.77 with r2 of 0.411. the minus sign (-) in the equation shows a negative relationship, therefore, an increase in height causes a decrease in the lst and vice versa. based on the map, the western and southern parts of the study location comprised mostly of andosols associated with brown and dark red mediterranean lithosol, regosol, and brown latosol. furthermore, soil type, texture and color affects the lst distribution. one of 315 fahrudin hanafi et al. / geosfera indonesia 6 (3), 2021, 301-318 the main ingredients of andosol soil, which is usually in the form of sand,is its ability to absorb high heat as well as to withstand low soil moisture within the range of 4 to 70% (bavel et al., 1972). meanwhile, hydromorphous alluvial soil types dominate the center, with clay as the parent material. it is also able to properly absorb a heat capacity of 0.279 calg-1 °c-1, although it is lower compared to sand (lal & shukla, 2004). vegetation is also considered to influence lst variation due to height, canopy character, and location of growth tendency. in accordance with the bps data, cloves, rubber, coffee, sengon, teak, and mostly rice fields and shrubs are cultivated in the eastern part of semarang regency. meanwhile, pine trees, fruits, bamboo, rubber, rice fields, and shrubs are cultivated in this regency at dense temperature fluctuations with high humidity and wind speed of 0.6 m/s.conversely, the cone canopy has a speed of 0.4 m/s and a higher temperature (fadlurrahman, 2018). 4. conclusion the dominant land cover in semarang regency from 2003 to 2018 was a forest with the tendency to be converted into agricultural areas. land cover predictions for 2028 also show a similar change pattern. furthermore, these changes had a positive relationship with lst and a significant effect with a correlation coefficient (r) of 0.655 (strong). forest, agricultural areas, open fields, shrubs and built-up areas affect 51.1%, 56.6%, 33.1%, 43.3%, and 28.5% on lst. land cover simulation shows that the built area is bound to increase by 18.56%, indicating dense growth in tengaran, east ungaran, bank, and kaliwungu district s. based on calculations, this caused an average increase of 28.9 ° c at a rate of 0.07 ° c/year. conflict of interest the authors declare that there is no conflict of interest with any financial, personal, other people or organizations related to the material in this study. acknowledgements the authors are grateful to the department of geography, faculty of social sciences, state university of semarang for their support in conducting this study and also to all those who provided and processed data. 316 fahrudin hanafi et al. / geosfera indonesia 6 (3), 2021, 301-318 references amiri, r., weng, q., alimohammadi, a., & alavipanah, s. k. (2009). spatial–temporal dynamics of land surface temperature in relation to fractional vegetation cover and land use/cover in the tabriz urban area, iran. remote sensing of environment, 113(12), 2606-2617. https://doi.org/10.1016/j.rse.2009.07.021. apriliyana, d. (2015). pengaruh perubahan penggunaan lahan sub das rawapening terhadap erosi dan sedimentasi danau rawapening. jurnal pembangunan wilayah dan kota, 11 (1), 103-116. https://doi.org/10.14710/pwk.v11i1.8661. artis, d.a., & carnahan, w. h. (1982). survey of emissivity variability in thermography of urban areas. remote sensing of environment, 12, 313–329. https://doi.org/10.1016/0034-4257(82)90043-8. bmkg. (2019). ekstrem perubahan iklim. retrieved from https://www.bmkg.go.id/. bps. (2015). luas penggunaan lahan menurut kabupaten/kota di jawa tengah tahun 2010. retrieved from https://www.bps.go.id/. bps (2017a). kabupaten semarang dalam angka 2017. retrieved from https://www.bps.go.id/. bps (2017b). luas lahan kritis menurut kecamatan di kabupaten semarang 2011-2016. retrieved from https://www.bps.go.id/. coll, c., galve, j m., sanchez, j.m., & casellez, v. (2010). validation of landsat-7/etm+ thermal band calibration and atmospheric correction with ground-based measurements. ieee, 48, 547–555. https://doi.org/10.1109/tgrs.2009.2024934. dadras, m., shafri, h.z.m., ahmad, n., pradhan, b., & safarpour, s. (2015). spatiotemporal analysis of urban growth from remote sensing data in bandar abbas city, iran, egypt. the egyptian journal of remote sensing and space science, 18(1), 3552. https://doi.org/10.1016/j.ejrs.2015.03.005. danoedoro, p. (2006). versatile land-use information for local planning in indonesia: contents, extraction methods and integration based on moderateand highspatial resolution satellite imagery. doctoral dissertation. university of queensland. estoque, r. c., murayama, y., & myint, s. w. (2017). effects of landscape composition and pattern on land surface temperature: an urban heat island study in the megacities of southeast asia. science of the total environment, 577, 349-359. https://doi.org/10.1016/j.scitotenv.2016.10.195. fadlurrahman, m. m. (2018). pengaruh naungan pohon dengan perbedaan bentuk tajuk dan jarak dari pohon terhadap kenyamanan termal di puspiptek serpong. doctoral dissertation. institut pertanian bogor. https://www.sciencedirect.com/science/article/abs/pii/s0034425709002405 https://ejournal.undip.ac.id/index.php/pwk/article/view/8661 https://www.sciencedirect.com/science/article/abs/pii/0034425782900438 https://www.bmkg.go.id/ https://www.bps.go.id/ https://www.bps.go.id/ https://www.bps.go.id/ https://ieeexplore.ieee.org/document/5208377 https://www.sciencedirect.com/science/article/pii/s1110982315000083 https://www.sciencedirect.com/science/article/abs/pii/s0048969716323853 317 fahrudin hanafi et al. / geosfera indonesia 6 (3), 2021, 301-318 fariz, t.r. (2016). pemanfaatan citra satelit dan sistem informasi geografis untuk pengembangan rth berdasarkan estimasi suhu permukaan daratan di kota pekalongan. jurnal geo-image, 5(1). https://doi.org/10.15294/geoimage.v5i1.11320. fu p. & weng q. (2016). a time series analysis of urbanization induced land use and land cover change and its impact on land surface temperature with landsat imagery. remote sensing of environment, 175, 205–214. https://doi.org/10.1016/j.rse.2015.12.040. igun, e., & williams m. (2018). impact of urban land cover change on land surface temperature. global j. environ. sci. manage, 4(1),47–58. https://doi.org/10.22034/gjesm.2018.04.01.005. kalinda, i. o. p., sasmito, b., & sukmono, a. (2018). analisis pengaruh koreksi atmosfer terhadap deteksi land surface temperature menggunakan citra landsat 8 di kota semarang. jurnal geodesi undip, 7 (3), 66-76. khandelwal, s., goyal, r., kaul, n., & mathew, a. (2018). assessment of land surface temperature variation due to change in elevation of area surrounding jaipur, india. egyptian journal of remote sensing and space science, 21(1),87–94. https://doi.org/10.1016/j.ejrs.2017.01.005. lal, r., & shukla, m. k. (2004). principles of soil physics. florida: crc press. li, z. l., tang, b. h., wu, h., ren, h., yan, g., wan, z., trigo, i. f., & sobrino, j. a. (2013). satellite-derived land surface temperature: current status and perspectives. remote sensing of environment, 131, 14-37. https://doi.org/10.1016/j.rse.2012.12.008. lillesand, t.m., kiefer r.w. & chipman, j. w. (2004). remote sensing and image interpretation (fifth edit). new jersey: john wiley & sons, inc. lin, x.-c., & yu, s.-q. (2005). interdecadal changes of temperature in the beijing region and its heat island effect. chinese journal of geophysics, 48(1), 47–54. https://doi.org/10.1002/cjg2.624. nugraha, s. b., sidiq, w. a. b. n., & hanafi, f. (2016). landsat image analysis for open spaces change monitoring to temperature changes in semarang city. paper presented at the lst international conference on geography and education (icge 2016), malang, indonesia. nuroniah, h. s., & putri, k. p. (2013). manual budidaya sengon. jakarta: pusat penelitian dan pengembangan peningkatan produktivitas hutan, badan penelitian dan pengembangan kehutanan. https://journal.unnes.ac.id/sju/index.php/geoimage/article/view/11320 https://journal.unnes.ac.id/sju/index.php/geoimage/article/view/11320 https://www.sciencedirect.com/science/article/abs/pii/s0034425715302625 https://www.gjesm.net/article_27798.html https://www.gjesm.net/article_27798.html https://ejournal3.undip.ac.id/index.php/geodesi/article/view/21217 https://www.sciencedirect.com/science/article/pii/s111098231730011x?via%3dihub https://www.sciencedirect.com/science/article/pii/s0034425712004749?via%3dihub https://agupubs.onlinelibrary.wiley.com/doi/10.1002/cjg2.624 318 fahrudin hanafi et al. / geosfera indonesia 6 (3), 2021, 301-318 pal, s., & ziaul, s. (2017). detection of land use and land cover change and land surface temperature in english bazar urban center. the egyptian journal of remote sensing and space sciences, 20, 125–145. https://doi.org/10.1016/j.ejrs.2016.11.003. pangi, p., ramadhan m., astuti k.d., harjanti i.m. & yesiana r. (2017). pola perkembangan ruang di kabupaten semarang dengan memanfaatkan data citra landsat. jurnal pengembangan kota, 5(1), 58-68. https://doi.org/10.14710/jpk.5.1.58-68. pu, r., gong, p., michisita, r., & sasagawa, t. (2006). assessment of multi-resolution and multi-sensor data for urban surface temperature retrieval. remote sensing of environment, 104, 211–225. https://doi.org/10.1016/j.rse.2005.09.022. pudjiono, s. (2014). produksi bibit jati unggul dari klon dan budidayanya. yogyakarta : balai besar penelitian bioteknologi dan pemuliaan tanaman hutan, direktorat jenderal bina usaha kehutanan. sarwono, j. (2006). metode penelitian kuantitatif dan kualitatif (1st ed.). sleman: graha ilmu. sukresno, b., jatisworo, d., & kusuma, d. w. (2018). analisis multilayer variabilitas upwelling di perairan selatan jawa. jurnal kelautan nasional, 13(1), 15. susanti, n.i., sanjoto t.b., & tjahjono h. (2012). aplikasi penginderaan jauh untuk analisis perubahan penggunaan lahan tahun 2002-2011 di daerah aliran sungai juana. geoimage, 1 (1), 69-74. https://doi.org/10.15294/geoimage.v1i1.949. tran, d.x., pla f., latorre-carmona p., myint, s. w., caetano, m., & kieu, h. v. (2017). characterizing the relationship between land use and land cover change and land surface temperature. isprs journal of photogrammetry and remote sensing, 124, 119–132. https://doi.org/10.1016/j.isprsjprs.2017.01.001. united nations (2018). 2018 revision of world urbanization prospects. new york: department of economic and social affairs. wang, s.q, zheng, x. q., & zang, x. b. (2012). accuracy assessment of land use change simulation based on markov-cellular automata model. procedia environmental sciences, 13, 1238–1245. https://doi.org/10.1016/j.proenv.2012.01.117. wang, s., ma, q., ding, h., & liang, h. (2018). detection of urban expansion and land surface temperature change using multi-temporal landsat images. resources, conservation and recycling, 128, 526-534. https://doi.org/10.1016/j.resconrec.2016.05.011. yuliati, a. (2018). hasil survei pertanian antar sensus (sutas) 2018 kabupaten semarang (a1 ed.). kabupaten semarang: badan pusat statistik kabupaten semarang. https://www.sciencedirect.com/science/article/pii/s1110982316301119 https://ejournal2.undip.ac.id/index.php/jpk/article/view/1000 https://www.sciencedirect.com/science/article/abs/pii/s0034425706001842 https://journal.unnes.ac.id/sju/index.php/geoimage/article/view/949 https://www.sciencedirect.com/science/article/abs/pii/s0924271617300035 https://www.sciencedirect.com/science/article/pii/s1878029612001181 https://www.sciencedirect.com/science/article/abs/pii/s0921344916301215 127 usman bolaji abdulkadir and animashaun kikelomo halimat / geosi vol 5 no 1 (2020) 127-146 inland water transport and urban mobility in ikorodu-ebutte ero route, lagos, nigeria usman bolaji abdulkadir* and animashaun kikelomo halimat department of geography and environmental management, faculty of social sciences, university of ilorin, pmb 1515, ilorin, nigeria *corresponding author: usman.ba@unilorin.edu.ng received 3 december 2019/ revised 25 march 2020/ accepted 14 april 2020/ published 27 april 2020 abstract lagos city has abundant navigable inland waterways which if fully harnessed would help minimise road traffic congestion, pollution and provide low cost means of long distance travel within the city. this study examines inland water transport services on lagos lagoon focusing on ikorodu-ebutte ero route. primary data were obtained using structured questionnaires. while, secondary data were sourced from relevant government and private agencies. data were analysed using descriptive techniques including frequency counts, tables and graphs. the results revealed an inadequate provision of terminal facilities and vessels in the area. it was also found that most (67.3%) of the trips via water transport in the were mainly for work purpose. in addition, low patronage was observed and it was found to be mostly due to comparatively high cost of fares and passenger safety concerns, as indicated by 67.4% and 58.7% of the respondents respectively. furthermore, high income earners where found to patronise this mode than low income earners. the high frequency of use of water transport by the respondents (71.3% travel by water every day) indicates that, this mode has great potential of being widely adopted, if greater attention is given to its development by both the government and private sector. there is, therefore, a need for more investment in water transportation in the area through the provision of modern infrastructure and vessels. keywords: urban mobility; inland waterways; transport services; sustainable transportation; integrated transport. 1. introduction modern cities are highly transport dependent and this makes it essential for cities to develop efficient transportation systems that provide effective links within the city and for both the national and global transportation systems (hoyle, 1993; kurniasari et al., 2018). a side from being the oldest means of transporting goods and services, inland waterways have been associated with facilitation of commerce, provision of employment and wealth creation among many other benefits (gray, 2004; fellinda, 2006; christodoulou et al., 2019; dai et al., 2019; wiercx et al., 2019; tanko et al., 2019; hossain et al., 2019). looking back to the period of the industrial revolution in europe, waterways played an essential role. they served geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.5 no. 1 (2020), 127-146, april, 2020 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v5i1.14714 accredited by the ministry of research , technology , and higher education of the republic of indonesia, no. 30/e/kpt/2019. mailto:usman.ba@unilorin.edu.ng https://jurnal.unej.ac.id/index.php/geosi https://drive.google.com/file/d/1rsnvas6cuhowhl5bj87cl2l6k5dqz7s6/view 128 usman bolaji abdulkadir and animashaun kikelomo halimat / geosi vol 5 no 1 (2020) 127-146 as initial corridors of transportation and many of them eventually became important areas of commerce and industrial development. several cities of the industrial revolution era (such as oslo, hamburg and liverpool among others) had most of their industrial and commercial activities located close to the waterfronts. however, from the mid-20th century, the importance of waterborne transport declined significantly with the increasing development of motorways and the associated inland urban sprawl development (international association of public transport, 2013). however, in the recent years, increasing congestion on urban roads has directed attention to the development of other more sustainable forms of transportation. in addition, the fact that efficient transportation systems serve as catalyst for sound land use planning is increasingly being recognised. both of these reasons have provided an opportunity for water transport to play more significant role in urban mobility schemes in many parts of the world (international association of public transport, 2013). water transport provides the opportunity for improving urban transportation by helping to provide faster (hardly experienced congestion), more efficient and better integrated transport services for the urban area (hoyle, 1993). nigeria has about 8,600 kilometres of inland waterways and an extensive area of coastland of over 800 kilometres (ndikom, 2013). up to early 1960s, inland waterways provided important routes for access from the coast to the hinterland and accounted for more than 30% of the total produce transported in the country. however, by the late 1960s the significance of this important means of transportation had declined. at present only about 3,000 kilometres of the country’s inland waterways is being harnessed (badejo, 2011). although, water transport is known to be comparatively cheaper and most efficient for riverine communities, this mode of transport is currently highly neglected and undervalued in the country (ndikom, 2013; adejare et al., 2017). lagos, the commercial capital of nigeria has been observed to possess the necessary inland waterway network capacity to transport commuters to most parts of the city, but the waterways are grossly under utilized. the existing water transport facilities are inadequate both in terms of size and access to commuters (adejare et al.,2017; ogunbajo et al., 2017). ademiluyi et al., (2016) also observe that in spite of the numerous merits of water transport such as the low cost, larger capacity and safety, this mode of transport is yet to be fully tapped to achieve the potential benefits it possesses. they, therefore, called for more attention to water transportation in the state, in terms of greater investment through public or private partnership. it has also been noted that the lagos state government’s 30 year transportation 129 usman bolaji abdulkadir and animashaun kikelomo halimat / geosi vol 5 no 1 (2020) 127-146 improvement plan of integrating the bus rapid transit (brt) with light rail schemes may not solve the congestion problem, except it also incorporatesthe water transport mode (edelman, 2015). the improvement of water transport in lagos has the potential to help address the serious road congestion and its associated problems such as extended travel time, loss of man hour, and negative effects on the environment and human health. if well-developed, water transport would help improve mobility since it could easily be organized to have fixed travel time because it hardly experiences congestion (bayode & ipingbemi, 2016; tobias et al., 2019; tannum & ulvensøen, 2019; iamtrakul & wongbumru, 2019; łapko & panasiuk, 2019; iamtrakul, 2018). focusing on water transport is important and relevant in lagos, because of its high potential for developing this mode of transport. it is also more economical and sustainable compared to road transport. this is because, in the long run, it entails less financial investment since it requires less maintenance and has higher capacity for passengers and goods. although some other studies (adejere et al., 2011; ademiluyi et al., 2016; ogunbajo et al., 2017) have been carried out on inland water transport in lagos state, this study is different from the previous ones because it specifically focuses on the ikorodu-ebutte ero route. this study also adopts both quantitative and qualitative methods essential for an indepth examination of activities on the lagos waterways. this study examines the operation of inland water transport along the ikorodu-ebute ero route in lagos city, with a view to recommend strategies for raising its capability as a mode of transportation in the area. the specific objectives are to: examine the available water transport facilities; determine its contributions to passenger movement; examine the characteristics of the passengers; as certain the problems associated with use of water transport; and to suggest possible strategies to improve water transportation in the area. 2. area of study lagos state is located between longitude 20 42' east and 30 42' east and latitude 60 22' north and 60 52' north, in the southwestern nigeria. it occupies an area of 3,475.1 km2 with 22% of the total land area consisting of creeks and lagoons. it lies entirely within the coastal plain and the land does not rise over 650 m above the sea level. most of its land area lies below 320 m above sea level and this subjects most of the areas to floods and beach erosion. 130 usman bolaji abdulkadir and animashaun kikelomo halimat / geosi vol 5 no 1 (2020) 127-146 according to the 1991 national census the state had a population of 5,725,116, which had increased to 9,113,605 by 2006. the population was estimated to have risen to 11 million by 2011 and to 12.5 million in 2016 (nigerian bureau of statistics (nbc), 2008 and 2013). the city’s metropolitan area which had a population of only 290,000 in 1950 is now estimated to have a population of over 12 million and it is expected to grow to be the world’s third largest city by 2050. seventeen out of the twenty local government areas (lgas) in the state fall within the metropolis while twelve lgas encompass riverine communities (figure 1). lagos state operates 12 ferry routes under the supervision of lagos state water authority (laswa). the routes as identified by ademiluyi (2016), bayode & ipingbemi (2016) are ikorodumarina/cms; marina-mile 2; ikorodu-addax/falomo; ikorodu-ebuteero, marinaijegunegba-ebuteojo; mile 2-marina/cms-mekwen-falomo; badore-ijede; badore-five cowries; marinaoworonshonki; ebuteojo-ijegunegba; oworonshonki-five cowries; and baiyekulangbasa. figure 1. lagos inland waterways routes transportation in the study area is mostly by road which accounts for about 90% of traffic flow in the area. despite the abundance of waterways in lagos, waterborne transport is not as popular as road transport to get around the city. apart from the few regular ferry 131 usman bolaji abdulkadir and animashaun kikelomo halimat / geosi vol 5 no 1 (2020) 127-146 services between lagos island and the mainland, fibre-covered motorised boats and canoes also operate passenger services on the lagoon and some of the creeks. 3. methods data used for this study include data on available water transport facilities, socioeconomic and travel characteristics of the passengers, passenger movement and challenges militating against the development of inland waterways in the area. secondary data were obtained from transport departments of riverine local government areas. official data were also obtained from the lagos state ministry of works and transport, lagos metropolitan area authority, lagos water authority and lagos ferry corporation. primary data were obtained through questionnaire survey using two types of questionnaire. questionnaire (a) was used to derive information from the union officials of vessel operators at the two operational jetties in the area, association of tourist boat operators of nigeria (atbownation) and sea coach water transport union. the data included number, types and capacity of vessels and number of trips made per day. other jetties in the area which are ikorodu terminal (operated by lagos state government) and metro ferry water transport were not in operation at the time of the survey. questionnaire (b) was used to gather information from users of water transport services. after it was estimated through a reconnaissance survey that about 3,000 passengers are transported through the two sampled jetties per day, five percent (150) of the passengers were sampled for the study. this is at 7.8 margin of error and 95% confidence level. systematic random sampling was used to select the passengers on whom the questionnaire was administered.the questionnaire survey was conducted with the aid of four research assistants who were adequately trained for the survey. the data collected were analysed using descriptive techniques including frequency counts, tables and graphs. 4. results and discussion 4.1 water transport facilities available in the area there are four jetties at ikorodu area of lagos state. these are the ikorodu terminal jetty (owned by the lagos state government), association of tourist boat operators and water transporter of nigeria (atbownation) jetty, metro ferry water transport jetty and sea coach water transport jetty (all privately owned). however, only two of them; atbownaton and sea coach water transport jetties were functional at the time of the study in june 2017. the main consequence of inadequate number of operational jetties in the 132 usman bolaji abdulkadir and animashaun kikelomo halimat / geosi vol 5 no 1 (2020) 127-146 area is that people were greatly restricted from accessing water transport mode in the area. the atbownaton jetty had a total of 56 vessels while sea coach jetty had 13 vessels operating from it as shown in table 1. table 1. available water transport vessels in the area name of jetty number of vessels capacity of vessels atbownation jetty 56 20 sea coach : 1. shutter 2. cruiser 3. coaster 1 2 10 2 31 35 total 69 88 as also shown in table 1, the vessels are of different capacity and quality. while the atbowanation use standard vessels of 20 passenger capacity, sea coach jetty operators use a variety of vessels with capacity between two to 35 passengers. most of the vessels were fibre covered locally manufactured vessels while a few were imported standard vessels which were more expensive. an examination of other supporting facilities in the area covered the car parking facilities, passengers’ lounge and other facilities. for instance atbownaton jetty has a car parking facility with the capacity of 80 cars while the sea coach’s facility has a capacity of 50 cars. the sea coach jetty has other facilities such as restaurant and restrooms which were not available at atbownaton jetty (table 2). table 2. other facilities at the jetty area facilities condition of facilities at sea coach jetty condition of facilities atbownation jetty car park capacity 50 cars 80 cars passenger’ lounge capacity 40 passengers 50 passengers jetty structure wooden wooden other facilities none restaurant and rest rooms 4.2 contributions of inland water transport to passengers movements in the area the study further examined the impact of water transport on movements of the people in the study area. the average number of passengers moved per day was estimated using the number and capacity of available water vehicles and the average number of trips made per day. it was found that on average, up to 2,842 passengers were transported by water per day along the ikorodu – ebutte-ero axis of lagos state (table 3). 133 usman bolaji abdulkadir and animashaun kikelomo halimat / geosi vol 5 no 1 (2020) 127-146 table 3. average number of passengers moved per day operators number of vessels capacity of vessels average trip per day total number of passengers per day atbownation 56 20 2 2240 sea coach : 1. shuttle 2. cruiser 3. coaster 1 4 10 2 31 35 2 2 1 4 248 350 total 2842 table 3 shows that atbownation jetty had a high number of passengers movement because of its larger number of water vessels (56) compared to the 15 vessels at sea coach jetty. in addition, the atbownation jetty had a bigger car park, larger waiting room and a restaurant as other facilities that could be attracting more passengers. it could however be deduced that the low number of passengers moved could not be adduced to shortage of vessels, but may be explained by a problem of low patronage. the fact that the vessels do not make more than two trips per day is a clear evidence of this problem. 4.3 characteristics of water transport passengers in the area 4.3.1 socio-economic characteristics majority (68%) of the respondents were found to be males. the preponderance of males among the passengers may be because males were more likely to take risk than females as travelling by water was perceived to be more dangerous than by road in nigeria. the long term neglect of water transport by successive governments has been observed to be responsible for travel safety concerns among the people (adeniyi, 2017). it was also found that most of the passenger fell within the middle aged group. for instance, 75.6% were between 26 – 45 years, while 58% of the passengers were married. in addition, a very high proportion (96.7%) of the respondents had secondary education and higher (table 4). this indicates that most of those who patronise water means of transport in the state were educated. furthermore, most (84%) of the passengers were employed with about 60% of them earning at least n 80,000 per month. 134 usman bolaji abdulkadir and animashaun kikelomo halimat / geosi vol 5 no 1 (2020) 127-146 table 4. social-economic characteristics of respondents characteristics characteristics frequency percentage 18 – 25 5 3.3 age 26 – 35 66 44 36 – 45 47 31.3 46 and above 32 21.3 total 150 100 single 46 30.7 married 87 58 marital status separated 5 3.3 divorced 4 2.7 widowed 8 5.3 no formal education 5 3.3 primary education level of education secondary education 8 5.3 tertiary education 83 55.3 others 54 36 private sector 73 48.7 self employed 29 19.3 government worker 24 16 occupation apprentice 0 0 student 10 6.7 unemployed 13 8.7 others 1 0.7 below ₦18,000 9 6 ₦18,000 ₦49,000 21 14 monthly income ₦50,000 ₦79,000 24 16 ₦80,000 ₦109,000 27 18 ₦110,000 and above 61 40.7 no reponses 8 5.3 4.3.2 travel characteristics the study also examines the travel characteristics of the respondents in the study area such as passengers preferred means of water transport, regularity of use of water transport and purpose of trip of the passengers among others. 4.3.2.1 preferred type of vessel this involved the examination of the respondents most preferred means of water transport among canoes, non-covered motorised vessels, fibre covered motorised vessels and ferry. results show that as high as 71.3% of the respondents preferred fibre covered motorised vessels while none of the respondents used canoe as shown in table 5. the 135 usman bolaji abdulkadir and animashaun kikelomo halimat / geosi vol 5 no 1 (2020) 127-146 preference for fibre-covered motorized vessel by majority of the respondents as shown in table 5 was expected because, it was faster and cheaper than other water vehicles in the area. meanwhile the preference for ferry by significant proportion of the respondent (23.3%) was because of its safety and better comfort when compared to the other available vessels. table 5. travel characteristics of the respondents characteristics frequency percentage preferred vessel type canoes 0 0 non-covered motorised vessel 0 0 fibre-covered motorised vessels 107 71.3 ferry 35 23.3 no response 8 5.3 total 150 100 regularity of travel by water everyday 107 71.3 at least once a week 10 6.7 at least once a month 7 4.7 occasionally 19 12.7 no respond 7 4.7 purpose of trip commerce and shopping 27 18.0 education 0 0 family and social purposes 14 9.3 work 101 67.3 others 0 0 no response 8 5.3 duration of journey less than 15 minutes 17 11.3 15-30 minutes 57 38.0 31-45 minutes 69 46.0 46 mins-1 hour 0 0 above 1 hour 0 0 no response 7 4.7 cost of journey less than ₦200 0 0 ₦200-₦500 0 0 ₦501-₦700 91 60.5 ₦701-₦1,000 53 35.3 above ₦1,000 0 0 no response 6 4.0 136 usman bolaji abdulkadir and animashaun kikelomo halimat / geosi vol 5 no 1 (2020) 127-146 4.3.2.2 regularity of travel by water transport regardingthe regularity of use of water transport by the respondents, it was found that71.3% of them travelled by water transport everyday. meanwhile, another 6.7% used it at least once a week as shown on table 5. 4.3.2.3 purpose of trips an examination of the purpose of trips shows that 67.3% of the respondents depended on water transport to travel to work, while 18% of the respondent’s used water transport for commercial and shopping journeys as also shown on table 5. most (71.3%) of the respondents were found to use water transportation on daily basis (table 5). 4.3.2.4 duration of journey the results further show that 46% of the respondents spent 31-45 minutes on their journey while the duration of trip for 11.3% was less than 15 minutes per trip as shown on table 5. it could be seen that travel time by water in the area was shorter than by road. 4.3.2.5 cost of trips the monetary cost of trips incurred by passengers who travelled by water was however found to be higher than that of road transport. for instance it was found that 60.7% of the respondent paid ₦500 ₦700 per trip, while 34.7% of them incurred between ₦701 to ₦1000 per trip as also shown in table 5. 4.4 problems associated with use of water transport in the area the users of inland water transport in the area faced some challenges associated with their usage of water transport in the area. they indicated problems such as inadequate number of water vessels, poor quality of vessels, lack of adequate security and inadequate safety equipment among others. 4.4.1 insufficient number of water vessels the study found that as high as 68% of the respondents opined inadequate supply of vessels as a problem militating against the development of water transportation in the area as shown in figure 2. as a result intending passengers often had to join long queues at the jetties to get on boats or ferries. 137 usman bolaji abdulkadir and animashaun kikelomo halimat / geosi vol 5 no 1 (2020) 127-146 figure 2. respondents’ opinion on inadequate number of water vessels as a problem 4.4.2 poor quality of vessels the results show that a high proportion of the respondents (62.6%) held an opinion that most of the vessels were of poor quality while 14.7% of the respondents strongly disagreed that poor quality of vessels was a problem of water transport in the area as shown in figure 3. figure 3. respondents’ opinion on poor quality of vessels as a problem 4.4.3 inadequate security inadequate security was seen to be a problem by 61.3% of the respondents as seen in figure 4. as a feed transport mode that did not provide door to door service, it required passengers using other modes of transport to get to the jetty from home. this may require people toparktheir personal cars at the jetty car park for the duration of office hours. figure 4. respondents’ opinion on inadequate security as a problem 33.3% 34.7% 15.3% 11.3% 0% 5.3% 0 10 20 30 40 strongly agree agree disagree strongly disagree i don't know no response 39.3% 23.3% 14.7% 14.7% 2.7% 5.3% 0 10 20 30 40 50 strongly agree agree disagree strongly disagree i don't know no response 32% 29.3% 20% 6.7% 6.7% 5.3% 0 10 20 30 40 strongly agree agree disagree strongly disagree i don't know no response 138 usman bolaji abdulkadir and animashaun kikelomo halimat / geosi vol 5 no 1 (2020) 127-146 4.4.4 inadequate transport safety results show that 58.7% of the respondents perceived transport safety as a problem of water transport in the area (figure 5). the main issues related to safety raised by the people included inadequate safety equipment particularly life jackets, poor boat condition and reckless driving by the operators. figure 5. respondents’ opinion on transport safety as a problem 4.4.5 high cost of transport cost of transport was seen as a problem by as high as 67.4% of the respondents, as seen in figure 6.for instance, a trip that would normally cost about ₦300 by road cost would cost between ₦500-₦700 by water. figure 6. respondents’ opinion on high cost of transport as a problem the results indicate that there was a gross inadequacy of terminal facilities and vessels for water transportation in the area. with only two out of five terminals in operation, the capacity of water transport to facilitate movements in the area had been greatly reduced. this was because access to this mode was denied or made difficult for many people in the area. in addition, the availability of other supporting facilities was very important because these could attract or discourage prospective passengers. this was in line with the findings of chukwuma (2014); bassey & nsa (2018) who noted that inadequate water transport facilities was a major factor impeding the development of inland water transport in nigeria. for 26.7% 32% 22% 10.7% 3.3% 5.3% 0 10 20 30 40 strongly agree agree disagree strongly disagree i don't know no response 40.7% 26.7% 18.7% 8% 0.7% 5.3% 0 10 20 30 40 50 strongly agree agree disagree strongly disagree i don't know no response 139 usman bolaji abdulkadir and animashaun kikelomo halimat / geosi vol 5 no 1 (2020) 127-146 instance, the adequately available car parking facilities allows people with personal cars to keep their cars safe while travelling by boat on a part of their trips, thereby avoiding traffic stress on lagos roads. on the daily basis, water transport contributed to the mobility of almost 3,000 people within the ikorodu-ebute ero axis of lagos city (see table 3). this was very low considering the hundreds of thousands of lagos commuters who continued to travel by road on daily basis. this was an evidence that the potential of water transport had remained mostly untapped in the area. this was in line with the observation of ademiluyi et al. (2016); bayode & ipingbemi (2016) that water transport moves only a small proportion of the total traffic in lagos state. however, while the number of commuters travelling by water in the area waslow,one should still appreciate the fact that these were people that would have added to the road traffic chaos in the area, either as public transport or personal cars passengers. improved access is therefore a major issue that needs to be addressed to maximise the utilisation of water transportation in the area. the two most preferred water vessels in the area were fibre-covered motorised vessels and ferries (table 5). the preference for fibre-covered motorised vessel by the commuters was expected because; it was faster than other water vehicles in the area. meanwhile, the preference for ferry was because of its safety and better comfort when compared to the other available vessels. this implies that the potential of this modes as an alternative to road transport will be greatly increased if more of these modern vessels are introduced into service in the area. the consistency in the use of water mode of transportation by most (71.3%) of the commutersusing this mode as seen in table 5 is a further indication of the great potentials of water transport in the city. this also in line with the findings of ademiluyi et al. (2016) who found a consistency in the use of water transport by most of the commuters traveling by water in lagos city. this further indicates that the patronage of water transport would likely increase with the provision of more jetties andother supporting infrastructure such as car parks that will provide more access to a larger number of people in the area. most of the trips via water transport in the area were based on work purpose. based on the urban transportation modelling system (utms) (flugel & flotterod, 2015) categorisation ofthe purpose of trip in the area into trip distribution based on origin and purpose, majority of the respondents fell within the home-work category. on the average travel to work by road in lagos took not less than 2-3 hours because of the prevalent traffic congestion. this resulted in lagos being regarded as the city with the highest level of road 140 usman bolaji abdulkadir and animashaun kikelomo halimat / geosi vol 5 no 1 (2020) 127-146 traffic congestion in nigeria. therefore, travelling by water at least part of the trip, allows commuters to avoid traffic congestion and reduces travel time though at higher financial cost. the higher rates charged per tripcompared to road travel can be attributed to the near monopoly enjoyed by the few private water transport operators. this is in line with the findings of ogunbajo et al. (2017) who also noted that high cost of travel is amajor problem of water transportation in lagos city. however, while on the surface it may seem more expensive because it implies substituting higher monetary cost for time, in the real sense it is more economical for the city because of the significant man-hour loses attributed to traffic congestion in lagos city. for instance, it was estimated that lagos commuters spent an average of 30 hours on traffic per week which was 75% of weekly working hours (business day online, 2018). however, for the fact that most of water transport users were of the high income earners,it can be deduced that the cost of transport likely plays a significant role in people’s decision to travel by this mode. the implication is that road travel may still continue to attract more lagos commuters because of the relatively lower rates charged. most of the problems associated with the use of water transport in the area are direct result of poor level of investment in this mode of transport. the long term neglect of inland water transport by successive governments has led to the handover of themode of transportto the hands of few private individuals and enterprises. the high cost of acquisition and maintenance of vessels became a major restriction to entrance into this line of business. this was largely responsible for the inadequate supply in the sector. for instance, a locally manufactured 15 seater open (without roof) motorised vessel cost between ₦200,000 ₦300,000 depending on whether it was made of wood or fibre (nwakunor et al., 2016). although, the wooden boats weremore common because of their lower cost, they were still not affordable to many people who may be interested in joining the business in the area. the poor quality of water vessels in the area was another evidence of the low level of development of this mode of transportation, particularly, when compared to road transport. this was another important factor that may discourage prospective passengers. for instance, while most of the boats were without roof (passengers were exposed to the elements), passengers also often had to sit on wooden planks with no backrest. only the roofed fibrecovered boats and ferries were equipped with comfortable chairs while also providing protection from the sun/rain. exposure to rain in particular has been observed to be a major complaint of water transport passengers in lagos (nwakunor et al., 2016). this is not surprising since it will be a serious discomfort to be soaked by rain while commuting to and from the office or school. 141 usman bolaji abdulkadir and animashaun kikelomo halimat / geosi vol 5 no 1 (2020) 127-146 while piracy was not identified as a problem to inland water transport in the area, traffic robberies, theft and other vices were known to be common around lagos jetties due to the presence of touts and other miscreants within and around their vicinity. therefore, passengers were sometimes exposed to some of these problems, such as breakage of their parked cars resulting in loss of valuables. in addition, operation of inland water transport in the area was largely dominated by informal business units and individual operators who wereoften uneducated, rash and aggressive just like their road transport counterparts. therefore, the passengers also often had to put up with verbal abuse and other forms of aggression. as seen in figure 5 the issue of safety was a problem to almost 60% of the commuters. passengers were particularly at risk due to non-adherence to government regulation on provision of life jackets by most operators. even when life jackets were provided they were often the cheapest ones in the market that were highly unreliable (bayode & ipingbemi, 2016). there were also other serious risks attached to navigation on the lagos lagoon such as collusion with other boats or floating logs and risk of fishing nets getting caught on propellers (adeniyi, 2017). for instance, a boat mishap which resulted in the loss of many lives was attributed to poor visibility during a night journey (punch, 2019). these hazards were particularly associated with night journeys which eventually made the state government to ban night travel on the lagos lagoon. poor condition of vessels was also reflected in form of rickety boats, for instance it is not uncommon to find vessels leaking water while travelling on the waterway. the safety issue was further compounded by the problem of overloading and over speeding and other reckless behaviour. for instance, bayode & ipingbemi (2016) attributed about 70% of accidents on the lagos waterways to human error. there was also the problem of hyacinths which often clog waterways, affecting engines and making it difficult to navigate. the high cost of water transport when compared to road mode of transport in lagos state was attributed to factors such as low supply compared to the present demand for their services and high cost of maintenance of vessels (nwakunor et al., 2016; bayode & ipingbemi, 2016).while this observation may be true for some parts of the lagos inland waterways, this conclusion cannot be deduced from this present study. this was because there was alow patronage in the area which could be seen from the low number of trips made by the available vessels. the most likely reason was probably the influence of union control which was usually very strong within the transport industry in the country. the transport unions often fixed rates and made their members abide through force and intimidation. high 142 usman bolaji abdulkadir and animashaun kikelomo halimat / geosi vol 5 no 1 (2020) 127-146 cost of transport may however be a great obstacle to widespread adoption of water transportation in the area, except measures are adopted to reduce cost of travel by this mode of transport. 4.5 possible strategies to improve water transportation in the area based on the findings of this study the following strategies are suggested: (1) to address the problems of gross inadequacy of terminal facilities and vessels for water transportation in the area, the lagos state government should invest more in inland water transportation. this will require the provision of more jetties and making abandoned ones functional. the state government can also provide ferry services to this area and other routes not presently served by government ferry services. this will go a long way in improving the capacity of this mode of transport to facilitate movement and ensure access to more people in the area; (2) there is a need for the operators to acquire modern boats and ferries that will be more reliable, safe and also provide greater comfort in terms of seating and protection from the sun and rain. this will attract more people to travel by this mode of transportation; (3) government should also provide incentives such as tax relief and as well as develop policies that would help facilitate access to credit for individuals and corporate organisations willing to invest in the this sub-sector. this will go a long way to attract investment in water transportation; (3) in addition, safety on the waterways can be improved through the strengthening of the lagos waterways authority (laswa), so that it can effectively perform the duty of enforcing safety regulations on the waterways. regulations such as the use of life jackets by all passengers and crew members, banning of night travels and adequate maintenance of vessels should be strictly enforced. this will help reduce the rate of accidents and fatalities often recorded; (4) security is a major issue that must be addressed to improve water transportation in the area. security on the waterways, areas around and within the jetties must be enforced to encourage more people to utilize this mode of transportation. in particular, car parking facilities around the jetties must be well protected so as to attract the patronage of car owners who commute partly on theroad; (5) there is also the need for public enlightenment on the need to adopt this mode of transportation, focusing on the advantages. this should mostly be directed at reducing the widespread sense of apathy concerning the use of water transport because of safety concerns among people in the area. 143 usman bolaji abdulkadir and animashaun kikelomo halimat / geosi vol 5 no 1 (2020) 127-146 5. conclusion this study examined inland water based transportation in the riverine parts of ikorodu area of lagos state. it was found that the capacity of water mode of transport was greatly reduced due to inadequate provision of jetties and other necessary facilities. therefore, access to this mode was largely denied or made difficult for many people in the area. however, despite the poor infrastructure, water transport played an important role by enhancing mobility in the area. particularly, it provided a fast and more sustainable means of movement within a city with a high level of road traffic congestion. in addition, the frequency of use by the commuters who travel by water is an indication that this mode of transport has a great potential of being adopted by a greater proportion of the population. however, relatively higher cost of journey compared to road travel, poor quality of vessels, safety related issues and poor security in the vicinity of jetties are the major obstacles that may discourage general adoption of water transportation in the area. therefore, while water transportation has great potentials in the area, there is the need for greater attention from both government and the private sector, to significantly raise its capacity to fully compliment the road transport mode. this could be facilitated through a greater investment in water transport infrastructure and provision of modern vessels. conflict of interest the authors declare that there is no conflict of interest with any financial, personal, or other relationships with other people or organizations related to the material discussed in the article. references adejare, q.a; olusina, j.o. and olaleye, j.b. (2017). empirically determined passenger ferry navigable routes within lagos lagoon. nigerian journal of technological development, 14 (2): 74-79 ademiluyi, i.a; fashola, o.k. and afolabi, o.j. (2016).analysis of intra-city water transportation in lagos.international journal of innovative research and advanced studies, 3 (8): 246-254 adeniyi, k. (2017). “lagos waterways passengers decry safety measures”. premium times online, november, 8, 2017. badejo, b. a. (2011).transportation removing the clogs to nigeria’s development. anchorage press and publishers: lagos, nigeria 144 usman bolaji abdulkadir and animashaun kikelomo halimat / geosi vol 5 no 1 (2020) 127-146 bassey, s. i. & nsa, m. e. (2018).problems and prospects of developing inland water transportation in nigeria: the case of calabar river. iosr journal of human and social sciences, 23 (7): 27-37 bayode, t. & ipingbemi, o. (2016). safety and operational characteristics of water based transportation in lagos state. scirea journal of traffic and transportation engineering, 1 (1): 13-31 business day online (2018).“lagos commuters lose 75% of weekly working hours to traffic”. december 11th, 2018. retrieved on 06/02/2019 from https://businessday.ng/news/article/lagos-commuters-lose-75-of-weekly-workinghours-to-traffic/ christodoulou, a., christidis, p., & bisselink, b. (2019). forecasting the impacts of climate change on inland waterways. transportation research part d: transport and environment, doi:10.1016/j.trd.2019.10.012 chukwuma, o. m. (2014).the characteristics of inland water transport in nigeria.iosr journal of humanities and social science, 19 (3): 119-126. dai, b. l., sheng, n., he, y. l., mu, f. h., xu, j. m., & zhu, a. f. (2019). development of an inland waterway traffic noise prediction model considering water surface adsorption and embankment shielding influences. international journal of environmental science and technology, 16(10), 5927-5936. doi:10.1007/s13762-01802186-2 edelman, d.j. (2015).an environmental plan for lagos, nigeria. international journal of social science, 3 (1): 201-279 fellinda, l. (2006). world’s water transport needs further development. transport and development, 1: 68-72 flugel, s. and flotterod (2015).traffic assignment for strategic transport model systems. paper presented at international transport economics association (itea) conference, june 17-19, 2015, university of oslo, oslo, norway. gray, l. (2004).an examination of the problems of water transportation in old degama province.journal of waterways, africa, 33: 20-26 hossain, n. u. i., nur, f., jaradat, r., hosseini, s., marufuzzaman, m., puryear, s. m., & buchanan, r. k. (2019). metrics for assessing overall performance of inland waterway ports: a bayesian network based approach. complexity, 2019 doi:10.1155/2019/3518705 hoyle, b.s. (1993). water transport and urban development: some geographical perspectives and propositions. geojournal, 31 (4): 439-448 iamtrakul, p., & wongbumru, t. (2019). exploring eco-friendly travel towards sustainable water transport in bangkok. paper presented at the iop conference series: earth and environmental science, , 398(1) doi:10.1088/1755-1315/398/1/012014 https://businessday.ng/news/article/lagos-commuters-lose-75-of-weekly-working-hours-to-traffic/ https://businessday.ng/news/article/lagos-commuters-lose-75-of-weekly-working-hours-to-traffic/ 145 usman bolaji abdulkadir and animashaun kikelomo halimat / geosi vol 5 no 1 (2020) 127-146 iamtrakul, p., raungratanaamporn, i., & klaylee, j. (2018). contribution on water transportation for resilient and sustainable lowland cities. lowland technology international, 20(3), 341-350 international association of public transport (2013).waterborne transport, a unique contribution to enhancing mobility for cities on water. a position paper of waterborne transport committee may 2013. kurniasari, e. and pramesty, d.a. (2018).the effects of vehicle intensity in sumbersari jember regency.geosfera indonesia, 3 (3): 50-58 łapko, a., & panasiuk, a. (2019). water tourism as a recipient of transport services on the example of szczecin. paper presented at the transportation research procedia, , 39 290-299. doi:10.1016/j.trpro.2019.06.031 ndikom, o.b.c. (2013). a critical assessment of the inland waterways operation and management on the development of the nigerian maritime industry. greener journal of environmental management and public safety, 2 (2): 99-107 nigerian bureau of statistics (2013).annual abstract of statistics, 2011.federal government of nigeria, abuja. retrieved on 11/06/19 from http://istmat.info/files/uploads/53129/annual_abstract_of_statistics_2011.pdf nigerian bureau of statistics (2018). 2017 demographic statistics bulletin, may. nwakunor, g.a., ajeluorou, a. and salau, g. (2016). lagos waterways: a hidden treasure untapped. retrieved on 06/11/2018 from http://m.guardian.ng/features/weekend/lagos-waterways-a-hidden-trasureuntapped/ ogunbajo, a.b., akinpelu, t.a. and odubela, c.a. (2017).the prospects and problems of water transportation in lagos metropolis.laspotech journal of scientific, engineering and technology research, 1 (1): 1-12 punch (2019). 12 bodies recovered in lagos boat mishap, five still missing. july 2 nd, 2019. retrieved on03/09/2019 from https://punchng.com/lagos-boat-accident-12-bodiesrecovered-five-still-missing/ tanko, m., cheemarkurthy, h., hall kihl, s., & garme, k. (2019). water transit passenger perceptions and planning factors: a swedish perspective. travel behaviour and society, 16, 23-30. doi:10.1016/j.tbs.2019.02.002 tannum, m. s., & ulvensøen, j. h. (2019). urban mobility at sea and on waterways in norway. paper presented at the journal of physics: conference series, , 1357(1) doi:10.1088/1742-6596/1357/1/012018 tobias, m. s. g., ramos, r. a. r., & rodrigues, d. s. (2019). use of waterway transport integrated to urban transportation systems in amazonian cities: a vision of sustainable mobility. wit transactions on ecology and the environment, 238, 615-625. doi:10.2495/sc190531 http://istmat.info/files/uploads/53129/annual_abstract_of_statistics_2011.pdf http://m.guardian.ng/features/weekend/lagos-waterways-a-hidden-trasureuntapped/ https://punchng.com/lagos-boat-accident-12-bodies-recovered-five-still-missing/ https://punchng.com/lagos-boat-accident-12-bodies-recovered-five-still-missing/ 146 usman bolaji abdulkadir and animashaun kikelomo halimat / geosi vol 5 no 1 (2020) 127-146 wiercx, m., van kalmthout, m., & wiegmans, b. (2019). inland waterway terminal yard configuration contributing to sustainability: modeling yard operations. research in transportation economics, 73, 4-16. doi:10.1016/j.retrec.2019.02.001 226 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 spatio-statistical analysis of rainfall and temperature distribution, anomaly and trend in nigeria elisha ademola adeleke* and eniola aminat orebayo department of geography & environmental management, university of ilorin, ilorin, 1515, nigeria *corresponding author: adelekeelisha@yahoo.com received 3 june 2019/ revised 16 may 2020 / accepted 14 june 2020/ available online 23 july 2020 abstract this study aims to examine the variability of rainfall and temperature based on spatiostatistical analysis. datazforzthezstudy was gotten from the nigerian meteorological agency and subjected to statistical analysis using mean, standard deviation, time series analysis, t-test and correlation. thezresultszofzthezstudyzrevealedzthatzthe mean rainfall in the area is 108.6 mm, mean temperature is 28o c and mean sunshine is 4.7 hours. the result further revealed that mean onset date in the state is 13th march, mean cessation date is 10th october while thezmeanzlengthzofzrainyzseason is 223 days. the result also showed that rainfall anomaly index in the area ranged between -2.12 and 2.28 while temperature anomaly ranged between -2.31 and 1.73. the correlation coefficient showed that cessation (0.408) and length of rainy season (0.406) is significantly related to rainfall, sunshine hours (0.380) and average temperature (0.867) is significantly related to minimum temperature, sunshine hours (-0.389) and average temperature (0.749) is significantly related to maximum temperature while onset (-0.642) and cessation (0.509) is significantly related to length of rainy season. however, there is a significant difference in onsetzdates,zcessationzdateszandzlengthzofzrainyzseasonzinzthezarea. the area is experiencing a significant increase in temperature, rainfall and sunshine hours and recommends that more tress should be planted in the area and nigerian meteorological agency should also inform farmers about the onset of the rains so as to help the farmers prepare for the planting season. keywords: climate; rainfall; anomaly; temperature; cessation; onset geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.5 no. 2 (2020), 226-249, august, 2020 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v5i2.11250 accredited by the ministry of research , technology , and higher education of the republic of indonesia, no. 30/e/kpt/2019. mailto:adelekeelisha@yahoo.com https://jurnal.unej.ac.id/index.php/geosi https://drive.google.com/file/d/1rsnvas6cuhowhl5bj87cl2l6k5dqz7s6/view 227 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 1. introduction rainfall is one of the major factors affecting food security especially in countries largely or highly dependent on rain-fed agriculture, given that, in addition to evaporation rate and soil characteristics, it controls the state of soil moisture. the role of moisture in agricultural production is even more important in the tropics, especially nigeria, where rainfall is highly seasonal over most parts and varies from year to year, while the growing season is determined by the availability of rain to meet crop water requirements (odekunle, 2004). the amount of rainfall that is normally received determines which types of agriculture that can be carried out and which crops can be cultivated in a region. the seasonal distribution of rainfall regulates the agricultural calendar in the tropics (vellinga et al., 2013). the relationship that exists between rainfall and the tropical occupation of agriculture in nigeria is that it employs over 80% of the work force. rainfall is arguably the most important meteorological parameter that has the greatest impact on human activity. rainfall distribution and pattern has been a major concern to different people in diverse field. i.e. to the agriculturist, rainfall is a crucial factor that determines the planting season and influences the type of crops to be cultivated. to the hydrologist, rainfall is important in generation of hydro electric power. the volume of water in rivers increases during the rainy season and this boost generation of electricity. morezactionszshouldzbeztakenztozsensitizezthezpubliczzaboutzzthezoccurrences ofwweatherzevents,zwhichziszfrequentznowadayszaszevidencezzofzzchangezzinzzthe climate (ayanlade et al., 2020). rainfall in nigeria is produced by the intertropical discontinuity. tropical analysts have consequently identified the boundary by several names such as the intertropical convergence zone (itcz), intertropical fronts (itf), and recently the intertropical discontinuity (itd). the itd is a warm, moist maritime air masses yielding heavy rainfall. rainfall is copious in all mouths with an annual total often being 250 cm (strahler & strahler, 1988). it is primarily a region of “maximum” surface moisture gradient, known as a humidity discontinuity (oyewo, 2005). 228 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 reductionzinzvolumezofzrainfallzandzsignificantzincreasezinzsurfaceztemperaturezwith thezfarmerszhavingzfirmzperceptionzofzthesezchanges (tarfa et al., 2020). warmer temperatures are very likely to produce more vigorous variability in climate such as increase evaporation, capacity of air to hold more moisture and thus heavier rainstorms. growing industrialization and increasing use of fossil fuels are putting pressure and affecting the regional and global temperatures that are subsequently influencing the overall precipitation levels. increasingztemperaturezandzchangingzpatternszof precipitationzarezamongzthezmanyzconsequences,zwhichzzarezzattributedzztozzclimate change (dammo et al., 2016). a change in temperature is an important indicator of global warming that directly determines the impact of climate change. recent concern about rising global temperature was justified by its negative impact in all sectors of the economy most especially water supply, ecosystems, coastal habitats, and industries. climatezchangezcouldzalterzgroundwaterzmainlyzthroughzchangeszinzthez recharge,z leadingztozmodifyzgroundwaterzlevels (guevara-ochoa et al., 2020). analysiszofzthezresponsesztozquestionszonzperceptionszofzextremezclimatezeffectszindicatedzthatzaboutz70%zofzthezfarmerszwerezawarezofzthezeffectszofzextremez climatezeventszonzcropzproductionzandzyield,zandzoverz50%zindicatedzthatztoozearly rainfall,zlatezrainfall,zprolongedzdrynesszafterzanzzinitialzrainfall,zzexcessivezzrainfall, windstormszwerezthezcommonzweather-relatedzcauseszofzlowzcropzyields (eludoyin et al.,z2017).zoceaniczand/orzatmosphericzinfluenceszonzthezzrainfallzzinzzbeninzzwere examinedzbyzinvestigatingzthezcorrelationzbetweenzthezprecipitationztimezserieszzand severalzindices (ahokpossi, 2018). furthermore, the report on cessation of the rainy season in the country indicated changes from “normal” between 1941 and 1970 to “early cessation” during the 1971 to 2000 period in most stations (nimet, 2008). nimet (2012) as certained that the period of the rainy season in the country has decline from 1941 while the signals of late onset and early cessation of the rainy season set in. thus, the length of the rainy season has remained shrinking, the annual total rainfall is almost the same, thereby giving rise to 229 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 occasional flash floods and drought occurrences during growing period. temperatures across the country showed an increasing trend from mid-20th century to date. the mean temperature anomaly indicated warming in most locations in the country. temperatures have increased from 0.2 to 0.5o c in the high ground areas of jos, yelwa and ilorin in the north and shaki, iseyin and ondo in the southwest to 0.9 to 1.9o c over the rest parts of the country. aiyelokun & odekoya (2016) stated that the temperature regimes from 1983 to 2013 in ijebu ode appears to be varying and changing statistically. furthermore, average temperature in ijebu ode is high in the dry season and low in the wet season and temperature is generally low during august break when rainfall seizes (aiyelokun & odekoya, 2016). thezwatershedzhaszbeenzsufferingzfromzirregularzandzerraticzrainfallzzduringz thezdryzseason.ztemperaturezexhibitedzazstatisticallyzsignificantzzrisingzztrendzzzwith minimumz temperaturezriseszfasterzthanzthatzofzthezmaximumztemperature (ketema &zsiddaramaiah,z2020).ztrendzforzmeanzandzminimumzaverageztemperatureszthrough timezsignificantlyzwhileztheztrendzforzmaximumztemperaturezexhibitedzaznonsignifi cantzincreasingztrendz(asfawzetzal.,z2018).zfactorszthatzmainlyzcorrelatezwithzstream flowzarezprecipitationzandzmaximumztemperaturez(tesfayezetzal.,z2017).zazwarming processzandzanzaccelerationzofzthezatmosphericzevaporativezzdemandzzzwhichzzztook zplacezespeciallyzsincezthezmid-1970s (elferchichi et al., 2017) ricezyieldzandztemperaturezhadzzgenerallyzzstatisticallyzzsignificantzzpositivez trends,zadaptationzstrategiesztozgeneticallyzmodifyzricezvarietieszandzeffectivezwaterz usezstrategieszinzareaszofzrainfallzdeficitzarezrecommendedztozensurezfoodzzsecurityz (akinbilezetzal.,z2020).zwarmzextremezdayszarezassociatedzwithzmidtroposphericzsub sidencezmotionzinzverticalzvelocityzanomalyzthatziszconnectedzwithzthezcorezofzzthez thermalzlowzandztheznetzzconvergentzzflowzzinzznigeriaz(abatanzetzal.,z2019).zthe trendszinzcoldznightszarezlargerzthanzforzcoldzdayszatzbothzthezannualzandzseasonalz scaleszinznigeriaz(abatanzetzal.,z2016). anzincreasingzztrendzzinzzbothzzrainfallzzand temperaturezinzannualzstatistics,zthough statisticallyzinsignificant (umar et al., 2019) 230 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 thezhighzvariationszofzrainfallzatzhigherzlatitudeszrevealzthezunreliableznaturezofzrain fallzaszonezprogressesztowardsznorthern guineazandzvicezversa (buba et al., 2017). thezobservedzspatiotemporalztrendszandzvariabilityzinzrainfallzarezimportantzbasiszfor guidingztargetingzofzappropriatezadaptivezmeasureszacrosszmultiplezsectors (muthoni et al., 2019). there have been limited studies concerned on spatio-statistical analysis of rainfall and temperature. therefore, this research intends to rainfall and temperature analysis based on onset, cessation and length of rainy season. this study aims to examine the variability of rainfall and temperature based on spatio-statistical analysis. 2. methods 2.1 study area the study area is ijebu ode in ogun state, nigeria (figure 1 and 2). the area experiences humid tropical climate which is characterized by alternate wet and dry season seasons like the rest of nigeria. ijebu-ode region on annual basis is under the influence of hot-wet tropical maritime air mass during the rainy season (april-october) and hot-dry tropical continental air mass during the dry season (november-march) (aiyelokun & odekoya, 2016). rainfall is generally heavy with peaks occurring in july and september (double maxima) coupled with high temperature, high evapotranspiration and high relative humidity. the average monthly rainfall for the area ranges between 7.1mm in the month of january to 208.27 mm in the month of june. the annual rainfall is between 1575 mm and 2340 mm. the temperature of the area ranges from 23o c during the dry season to 35o c during the rainy season with an average annual temperature is 27.5o c. furthermore, the area experiences relative humidity of 63 % in the dry season to as high as 95 % during the peak of the rainy season (onakomaiya, 2000). 231 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 figure 1. map of ogun state showing ijebu ode figure 2. map of ijebu ode 232 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 the vegetation of the area is of the tropical rainforest vegetation of nigeria. in terms of vegetation, the state can be divided into three distinctive zones. where the state shares a boundary with the atlantic ocean, the vegetation is of a swampy type with mangroves and other edaphic trees. about 400 km2 is of basement complex rocks of precambrian formation. the whole state is drained by flowing coastal rivers such as ogun, yewa, and shasha from oyo state through the thickly vegetated western part of the state. numerous small rivers and streams are at the south eastern parts flowing perennially through the swampy terrain. according to the national population commission (2006 census), ijebu-ode local government area has a population of 154,032, and an estimated population of 222,653 (2007). the state has enormous industrial potentials. there are also other modern industries producing high quality beer, bicycle tyres, ceramic goods, high quality clay bricks, carpet and clothing materials (onakomaiya, 2000). the data required for the study include mean and annual temperature, rainfall and sunshine hours between 1983-2017. these data were collected from the nigeria meteorological agency (nimet) at the headquarters in oshodi lagos state while the map of ijebu ode was extracted from the administrative map of nigeria using arc gis 10.3 software. onset of the rainy season will be compiled using walter (1967) formula because of its higher reliability in predicting the onset of the rains among different methods. the formula is expressed in equation 1. onset = dm (51-a) (1) tm where dm = number of days of the month containing the onset of rainfall, a = total rainfall for the previous month, tm = total rainfall for the month in which 51 mm or more is reached. the cessation of rainy season is defined as the last occasion of rainfall that record rainfall of 51 mm and above. cessation of the rainy season will be compiled using walter 233 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 (1967) formula because of its higher reliability in predicting the onset of the rains among different methods. the formula is expressed in equation 2. cessation = dm (51-a) (2) tm where dm = number of days of the month containing the cessation of rainfall, a = total rainfall for the previous month, tm = total rainfall for the month in which 51mm or more is reached. therefore, the length of the rainy season is the total number of days between the onset and cessation date. the anomaly index expresses the degree of rainfall and temperature anomaly for the relevant periods in relation to the long term mean rainfall and temperature for the study period. to calculate the rainfall and temperature anomaly for the study period, standardize rainfall anomaly index (sai) will be used. the formula is given in equation 3. sai = 𝑋− x 𝑆𝐷 (3) where x = mean annual rainfall or temperature, x = mean of entire series, sd = standard deviation of the entire series. correlation will be used to measure the relationship between the rainfall and temperature for the study period. 𝔯 = 𝑛(σ𝑥𝑦)−(σ𝑥)(σ𝑦) √[𝑛σ𝑥2−(σ𝑥)2][𝑛σ𝑦2−(σ𝑦)2] (4) where, 𝑦 = temperature, and 𝑥 = rainfall. t test was used to ascertain whether there is a significant difference between onset dates, cessation dates and length of rainy season in the area. time series is defined as a series of observation assumed by a variable over successive time periods. time series analysis helps to fit an array of time bound data on a line of best fit, it helps to show the type of trends existing in the data graphically. time series will be used to examine the trends of rainfall and temperature for the study period and for predict for the future years. the trend line equation of a time series data is as shown in equation 5. 234 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 y= a+b(x) (5) where, a =intercept, b= rate of change per time, and x= coded values of years. 3. results and discussion 3.1 descriptive statistics of onset, cessation and length of rainy season table 1 presents the onset dates, cessation dates and length of rainy season in the area for the study period. during the study period, rainfall started lately in 1983, rainy season started on 16th april (106th day of the year) while it started earliest in 2004, rainy season started on february 3rd (34th day of the year). the mean onset date of rain in the area during the study period is 13th march (72nd day of the year) with a standard deviation of 18.8 and a coefficient of variation of 25.7 %, this implies that onset date during the study period is heterogeneous. furthermore, rainy season started in february in 1982, 1986, 1987, 1991, 1993, 1996, 1999, 2003, 2004 and 2011 respectively, it started in march in 1981, 1984, 1985, 1988, 1989, 1994, 1995, 1997, 2000, 2002, 2005, 2006, 2012, 2013, 2014, 2015 and 2016 respectively while it started in april in 1983, 1990, 1998, 2001, 2007, 2008, 2009, 2010 and 2017. this result shows that rainfall starts within the month of february to april in the study period. also, during the study period, 27 % of the onset dates was in february, 46 % in march while 27 % was in the month of april. in table 1, the earliest cessation date of the rainy season in the area was in 1983 which occurred on september 22nd (265st day of the year) while the latest cessation date was in 1990 which occurred in the 10th of december (344st day of the year). the mean cessation date of the rainy season in the area during the study period is october 23rd (296th day of the year) with a standard deviation of 15.8 and a coefficient of variation of 5.3%. this implies that cessation dates during the study period was homogeneous. also, cessation dates in 1982, 1983, 1985, 1986, 1987, 1989, 1991, 1993, 1995, 1996, 2000, 2001, 2003, 2004, 2005, 2006 and 2008 are lower than the mean value of 23rd october while cessation dates in 1981, 1984, 1988, 1990, 1997, 1999. 2007, 2009, 2010, 2011, 235 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 2012, 2013, 2014, 2015, 2016 and 2017 are higher than the mean value and cessation dates in 1992, 1994 and 1998 are the same dates with the mean value of 23rd october. table 1. onset, cessation and length of rainy season year onset date julian day cessation date julian day length of rainy season 1981 15th march 74th day 1st november 305th 231 1982 25th february 56th day 17th october 290th 234 1983 16th april 106th day 22nd september 265th 159 1984 8th march 68th day 23rd october 297th 229 1985 20th march 79th day 21st october 294th 215 1986 27th february 58th day 11th october 284th 226 1987 14th february 45th day 19th october 292nd 247 1988 6th march 66th day 26th october 300th 234 1989 9th march 68th day 22nd october 295th 227 1990 11th april 101st day 10th december 344th 243 1991 23rd february 54th day 19th october 292nd 238 1992 9th april 100th day 22nd october 296th 196 1993 21st february 52nd day 20th october 293rd 241 1994 15th march 74th day 23rd october 296th 222 1995 10th march 69th day 20th october 293rd 224 1996 17th february 48th day 18th october 292nd 244 1997 23rd march 82nd day 9th december 343rd 261 1998 14th april 104th day 23rd october 296th 192 1999 26th february 57th day 26th october 299th 242 2000 21st march 52nd day 15th october 289th 237 2001 4th april 94th day 26th september 269th 175 2002 29th march 88th day 24th october 297th 209 2003 25th february 56th day 17th october 290th 234 2004 3rd february 34th day 23rd september 267th 233 2005 13th march 72nd day 28th september 271st 199 2006 7th march 66th day 20th october 293rd 227 2007 1st april 91st day 29th october 302nd 211 2008 9th april 100th day 20th october 294th 194 2009 2nd april 92nd day 13th november 317th 225 2010 11th april 101st day 11th november 315th 214 2011 21st february 52nd day 26th october 299th 247 2012 13th march 73rd day 26th october 300th 227 2013 6th march 65th day 26th october 299th 234 2014 11th march 70th day 26th october 299th 229 2015 15th march 74th day 25th october 298th 224 2016 12th march 72nd day 30th october 304th 232 2017 3rd april 93rd day 27th october 300th 207 mean 13th march 73nd day 23rd october 296th day 223 std 18.8 15.8 20.8 cv (%) 25.7 5.3 9.3 note : cv = climatic variable, std = standard deviation 236 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 as shown in table 1, the lowest length of rainy season of 159 days was recorded in 1983 while the highest of 261 days was recorded in 1997. the mean length of rainy season in the area is 223 days with a standard deviation of 20.8 and a coefficient of variation of 9.3%. this implies that the length of rainy season in the area is homogeneous. furthermore, length of rainy season in 1983, 1985, 1992, 1994, 1998, 2001, 2002, 2005, 2007, 2008, 2010 and 2017 are lower than the mean value of 223 days while length of rainy season in 1981, 1982, 1984, 1986, 1987, 1988, 1989, 1990, 1991, 1993, 1995, 1996, 1997, 1999, 2000, 2003, 2004, 2006, 2009. 2011, 2012, 2013, 2014, 2015 and 2016 are higher than the mean value of 223 days. 3.2 pattern of onset dates figure 3 presents the pattern of onset date of rainy season in the area during the study period. the trend of onset date is upward sloping, this implies that rainfall is starting late in the study period. the trend also shows that the latest date of onset was in 1983 while the earliest date was in 2004. this result implies that onset dates in the area is affected by climate change, rain now starts late in the study area. figure 3. pattern of onset dates y = 0.2065x + 43170 11-dec 31-dec 20-jan 09-feb 01-mar 21-mar 10-apr 30-apr 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005 2007 2009 2011 2013 2015 2017 o n se t d a te year onset date linear trendline 237 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 3.3 pattern of cessation dates as shown in figure 4, the trend of cessation dates in the area is upward sloping, this implies that cessation dates in the study area is getting late. furthermore, the earliest cessation date was in 1983 while the latest was in 1990. also, the trend shows that cessation dates where early between 1981 to 1996 and late between 1997 and 2017. this result shows that climate change has led to late cessation of rainfall in the area. figure 4. pattern of cessation dates 3.4 pattern of length of rainy season as shown in figure 5, the trend of length of rainy season is downward sloping, this implies that there is a decreased in the length of rain season in the area. also the result of the trend line equation y = -0.0512x + 224.3 is negative, meaning that the area has been experiencing a significant decrease in length of rainy season over the period of 35 years. this further shows a predicted rate of decrease of about -0.0512 per annum. the y = 0.1479x + 43393 08-aug 28-aug 17-sep 07-oct 27-oct 16-nov 06-dec 26-dec 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005 2007 2009 2011 2013 2015 2017 c e ss a ti o n d a te s year cessation date linear trend 238 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 decrease in the length of rainy season is as a result of late onset of rainfall and early cessation. figure 5. length of rainy season 3.5 anomalous rainfall and temperature table 2 presents the years with anomalous rainfall in the study area during the study period. 1994 experienced the driest year with an anomaly index of -2.12 while 2011 experienced the wettest year with an anomaly index of 2.28. furthermore, 1985 recorded the coldest year with a temperature anomaly index of -2.31 while 2006 recorded the hottest year with a temperature anomaly index of 1.73. y = -0.0512x + 224.3 r² = 0.0007 0 50 100 150 200 250 300 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005 2007 2009 2011 2013 2015 2017 le n g th o f th e r a in y s e a so n year length of rainy season linear trendline 239 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 table 2. anomalous rainfall and temperature year anomalous rainfall anomalous temperature 1981 0.92 -0.38 1982 -1.66 -1.15 1983 -1.47 -0.38 1984 -0.67 0 1985 0.03 -2.31 1986 -1.82 -1.35 1987 0.82 1.35 1988 1.08 0 1989 0.81 -0.58 1990 -0.69 1.35 1991 -0.47 0 1992 -0.46 -0.38 1993 -0.39 0.19 1994 -2.12 0 1995 -0.45 0.96 1996 1.09 0.58 1997 0.63 0.01 1998 -0.30 0.03 1999 1.92 0 2000 0.03 0.38 2001 -1.35 0.58 2002 0.23 0.58 2003 -0.32 0.77 2004 -0.16 0.58 2005 -1.39 -0.19 2006 -0.50 1.73 2007 1.12 -1.73 2008 0.38 -0.77 2009 0.61 -1.92 2010 1.00 -1.92 2011 2.28 -0.19 2012 0.26 0.19 2013 0.46 0 2014 0.51 0.19 2015 0.02 1.35 2016 0.32 0.58 2017 -0.29 1.35 in figure 6, 1982, 1983, 1984, 1986, 1990, 1991, 1992, 1993, 1994, 1995, 1998, 2001, 2003, 2004, 2005, 2006 and 2017 experienced negative anomaly, this implies that these years are dry experiencing rainfall below the normal while 1981, 1985, 1987, 1988, 1989, 1996, 1997, 1999, 2000, 2002, 2007, 2008, 2009, 2010, 2012, 2013, 2014, 2015 240 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 and 2016 experienced positive anomaly, rainfall received in this years are above the normal. figure 6. anomalous rainfall figure 7 presents the graph of temperature anomaly in the area for the study period. temperature recorded in 1981, 1982, 1983, 1985, 1986, 1989, 1992, 2005, 2007, 2008, 2009, 2010 and 2011 showed a negative anomaly while 1987, 1990, 1993, 1995, 1996, 1997, 1998, 2000, 2001, 2002, 2003, 2004, 2012, 2014, 2015 and 2016 showed a negative anomaly. also, 1984, 1988, 1994, 1999 and 2013 experienced a normal temperature for the study area. -2.5 -2 -1.5 -1 -0.5 0 0.5 1 1.5 2 2.5 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020 anomalous rainfall 241 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 figure 7. anomalous temperature 3.6 relationship between rainfall and temperature table 3 presents the correlation coefficients between rainfall and temperature in the study area. the minimum temperature (r = 0.084), sunshine hours (r = 0.220), cessation (r = 0.641) and length of rainy season (0.406) are positive. this implies that minimum temperature, sunshine hours, cessation and length of rainy season are directly related to rainfall amount. however, if minimum temperature, sunshine hours, cessation -3 -2.5 -2 -1.5 -1 -0.5 0 0.5 1 1.5 2 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020 anomalous temperature 242 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 and length of rainy season increases, rainfall increases and if minimum temperature, sunshine hours, cessation and length of rainy season decreases, rainfall decreases. furthermore, the maximum temperature (r = -0.191), average temperature (r = -0.044) and onset (r = -0.119) are negative; this implies that maximum temperature, average temperature and onset are inversely related to rainfall amount. if maximum temperature, average temperature and onset increases, rainfall decreases and if maximum temperature, average temperature and onset decreases, rainfall increases. the implication of this maximum temperature and average temperature influences rainfall in the area. as indicated in table 3, the correlation coefficient of maximum temperature (0.325), sunshine hours (0.380), average temperature (0.867), cessation and length of rainy season (0.080) is positive. this means that there is a directly relationship between minimum temperature and maximum temperature, sunshine hours’ average temperature and length of rainy season. however, implies that if these variables increase, minimum temperature will increase and if these variables decrease, minimum temperature will decrease. also, onset (-0.118) and cessation (-0.026) is negative; this implies that there is an inverse relationship between onset date, cessation date and minimum temperature. table 3. relationship between the climatic variables variable rainfall min. temp max. temp sunshine average temp. onset cessation lrs rainfall 1 min t. 0.080 1 max t. -0.191 0.325* 1 sunshine 0.220 0.380* -0.389* 1 average t. -0.044 0.867* 0.749* 0.069 1 onset -0.119 -0.118 -0.203 -0.141 -0.191 1 cessation 0.408* -0.026 -0.031 0.079 -0.031 0.318 1 lrs 0.406* 0.080 0.131 0.101 0.131 -0.642* 0.509* 1 note : lrs = length of rainy season, temp./t. = temperature furthermore, the correlation coefficient average temperature (r = 0.749) and length of rainy season (r = 0.131) is positive, this implies that there is a direct relationship between average temperature, length of rainy season and maximum 243 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 temperature. also, sunshine hours (r = -0.389), onset (r = -0.203) and cessation (r = 0.031) is negative, this implies that there is an inverse relationship between sunshine hours, onset, cessation and maximum temperature. in the same vein, the correlation coefficient average temperature (r = 0.069), cessation (r = 0.079) and length of rainy season (r = 0.201) is positive, meaning that there is a direct relationship between average temperature, cessation, length of rainy season and sunshine hours. further, onset (-0.141) is negative; this implies that there is an inverse relationship between onset and sunshine hours. also, the correlation coefficient length of rainy season (0.189) is positive; this implies that there is a direct relationship between length of rainy season and average temperature while onset (-0.191) and cessation (0.031) is negative, this implies that there is an inverse relationship between onset, cessation and average temperature. furthermore, the correlation coefficient, length of rainy season (-0.642) is negative, this implies that there is an inverse relationship between length of rainy season and onset. while onset (-0.642) is inversely related to length of rainy season. in the same vein, cessation (0.509) is directly related to length of rainy season. furthermore, cessation (0.408*) and length of rainy season (0.406*) are significantly related to rainfall, minimum temperature (0.325*), sunshine hours (0.380*) and average temperature (0.867*) is significantly related to minimum temperature. in the same vein, sunshine hours (-0.389*) and average temperature (0.749*) are significantly related to maximum temperature. also, onset (-0.642*) and cessation (0.509*) are significantly related to length of rainy season. 3.7 significant difference between climatic variables table 4 presents the result of student t test to determine if there is significant difference in onset dates, cessation dates and length of rainy season. since calculated t (23.539) is greater than p-value (2.028) for onset; we reject the null hypothesis and accept 244 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 the alternative hypothesis which states that there is a significant difference in onset dates in the study area. table 4. t test at 0.05 significant level test value = 0.95 t df sig. mean difference 95% confidence interval of the difference lower upper onset 23.539 36 2.028 73.13514 66.8339 79.4364 cessation 113.527 36 2.028 296.45946 291.1634 301.7555 lrs 65.148 36 2.028 223.32432 216.3721 230.2765 note : lrs = length of rainy season in the same vein, since calculated t (113.527) is greater than p-value (2.028) for cessation, thus, we reject the null hypothesis and accept the alternative hypothesis which states that there is a significant difference in cessation dates in the study area. furthermore, since calculated t (65.148) is greater than p-value (2.028) for length of the rainy season, we reject the null hypothesis and accept the alternative hypothesis which states that there is a significant difference in length of rainy season in the study area. this result implies that onset dates in the area is affected by climate change, rain now starts late in the study area. these results are similar to those reported by zhang & fueglistalerz(2019)zthatzchangeszinzthezatmosphericzcirculationzpatternzcanzzenhance rainfallzinzone placezandzsuppresszrainfallzinzanother. climate change also has led to latezcessationzofzrainfallzinzthezarea.zthesezresultszarezsimilarztozthosezreportedzzby (baezetzal.,z2019)zthatzbyzthezzoccurrencezzofzzallzzdifferentzztypeszofzzdroughtszisz associatedzwithzextremezmeteorologicalzzdroughts,zzwhichzzarezzmainlyzzcausedzzby precipitationzdeficitszinzthezwetzseasonzorzprolongedzrainfallzshortages.zthesezresults arezsupportedzbyzyacoubz&ztayfurz(2020)zthatztherezziszzpronouncedzzdecreasezzin precipitationzatzthezsouthernzregion,zreachingztozalmostzaztotalzzofz300zzmmzzdeficit innearlyz100-yearzperiod. 245 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 the trend of length of rainy season is downward sloping, this implies that there is azdecreasedzinzthezlengthzofzrainzseasonzinzthezarea.zthesezzresultszzwerezzdifferent fromzthosezofzzhangz&zzhouz(2019),zwhozreportedzthatzzforzzthezzglobalzzmonsoon regionzaszazwhole,zsignificantzzincreaseszinzzextremezprecipitationzzandzzassociations withzglobalzwarmingzare alsozidentified,zhoweverzwithzlimitedzspatialzcoverage. the years with anomalous rainfall in the study area during the study period. thesezresultszarezsimilarztozthosezreportedzby olaniyan et al. (2019) zthatzthezintertropicalzdiscontinuityz(itd)zandzzthezzseazzsurfaceztemperaturezz(sst)zzoverzzthe centralzpacific,zexhibitzdirectzteleconnectionzwithzthezonset anomaly. these results are supportedzbyzfitzpatrickzetzal.z(2019)zthatzazpotentialzusezofzlocalzonsetzregionszare presentedzthatzshowszthezlinkzbetweenzthezannualzintertropicalzfrontzprogressionzand localzagronomiczonset. if maximum temperature, average temperature and onset increases, rainfall decreases and if maximum temperature, average temperature and onset decreases, rainfall increases. thesezresultszarezsimilarztozthose reportedzby zsharma et al.z(2018)zthatzthezincreasezzinzzfrequencyzandzzmagnitudezofzextremezzrainfallzzhas beenzattributedztozthezincreasingztrendzzinzzmaximumzzandzzminimumzztemperature. thesezresultszarezsupportedzbyzmeshramzetzal.z(2018)zthatzthezzmonsoonzzandzzthez winter seasonzexhibited aznegativeztrendzinzrainfallzchangeszoverzthezperiodzofzstudy. 4. conclusion the area is experiencing a significant increase in minimum temperature, sunshine hours, rainfall and average temperature while it is experiencing a significant decrease in maximum temperature. however, rains start early in the area and ceases late, resulting to a prolonged length of rainy season because the area is experiencing a decline in the length of rainy season. it could also be noted that onset dates of rains and cessation dates are major determinants of length of rainy season as a change in any of the two variables will affect the length of the rainy season. the rainfall anomaly over all the area revealed that there was a composite nature in which. early warning systems about extreme 246 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 temperature and rainfall events should be put in place. this will help reduce the cost of destruction caused by this extreme weather events especially in the case of flood. early warning about temperature events can help prevent disease such as meningitis that is related with temperature. the response should involve flood forecasting and early warning using rainfall data, rescue and evacuation and post flood impact assessment, recovery and rehabilitation. conflict of interest the authors declare that there is no conflict of interest with any financial, personal, or other relationships with other people or organizations related to the material discussed in the article. references abatan, a. a., abiodun, b. j., adefisan, e. a., & gutowski, w. j., jr. (2019). hot days and tropical nights in nigeria: trends and associated large-scale features. theoretical and applied climatology, 137(3-4), 2077-2093. doi:10.1007/s00704-018-2713-0. abatan, a. a., abiodun, b. j., lawalc, k. a., & gutowski, w. j., jr. (2016). trends in extreme temperature over nigeria from percentile-based threshold indices. international journal of climatology, 36(6), 2527-2540. doi:10.1002/joc.4510. ahokpossi, y. (2018). analysis of the rainfall variability and change in the republic of benin (west africa). hydrological sciences journal, 63(15-16), 2097-2123. doi:10.1080/02626667.2018.1554286. aiyelokun, o., & odekoya, o. (2016). analysis of trend and variability of atmospheric temperature in ijebu-ode, southwest nigeria. international research journal of agriculture science, 6(2), 025-031. akinbile, c. o., ogunmola, o. o., abolude, a. t., & akande, s. o. (2020). trends and spatial analysis of temperature and rainfall patterns on rice yields in nigeria. atmospheric science letters, 21(3) doi:10.1002/asl.944. 247 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 asfaw, a., simane, b., hassen, a., & bantider, a. (2018). variability and time series trend analysis of rainfall and temperature in northcentral ethiopia: a case study in woleka sub-basin. weather and climate extremes, 19, 29-41. doi:10.1016/j.wace.2017.12.002. ayanlade, a., omotoso, f. e., bisiriyu, l. a., jegede, m. o., & ayanlade, o. s. (2020). communicating climate change impacts as manifested in extreme weather: a case of newspapers’ reports in nigeria. in handbook of climate services (pp. 401-421). springer, cham. bae, h., ji, h., lim, y. -., ryu, y., kim, m. -., & kim, b. -. (2019). characteristics of drought propagation in south korea: relationship between meteorological, agricultural, and hydrological droughts. natural hazards, 99(1) doi:10.1007/s11069-019-03676-3. buba, l. f., kura, n. u., & dakagan, j. b. (2017). spatiotemporal trend analysis of changing rainfall characteristics in guinea savanna of nigeria. modeling earth systems and environment, 3(3), 1081-1090. doi:10.1007/s40808-017-0356-2. dammo, m. n., yadima s. g & sangodoyin, a.y. (2016). modeling trends of temperature effects on water level of rivers in n/e nigeria. civil and environmental research. 8(4), 13-17. elferchichi, a., giorgio, g. a., lamaddalena, n., ragosta, m., & telesca, v. (2017). variability of temperature and its impact on reference evapotranspiration: the test case of the apulia region (southern italy). sustainability (switzerland), 9(12) doi:10.3390/su9122337. eludoyin, a. o., nevo, a. o., abuloye, p. a., eludoyin, o. m., & awotoye, o. o. (2017). climate events and impact on cropping activities of small-scale farmers in a part of southwest nigeria. weather, climate, and society, 9(2), 235-253. doi:10.1175/wcas-d-16-0032.1. fitzpatrick, r. g. j., bain, c. l., knippertz, p., marsham, j. h., & parker, d. j. (2016). on what scale can we predict the agronomic onset of the west african monsoon? monthly weather review, 144(4), 1571-1589. doi:10.1175/mwr-d-150274.1. guevara-ochoa, c., medina-sierra, a., & vives, l. (2020). spatio-temporal effect of climate change on water balance and interactions between groundwater and surface water in plains. science of the total environment, 722 doi:10.1016/j.scitotenv.2020.137886. 248 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 ketema, a., & siddaramaiah, d. g. (2020). trend and variability of hydrometeorological variables of tikur wuha watershed in ethiopia. arabian journal of geosciences, 13(3) doi:10.1007/s12517-020-5139-9. meshram, s. g., singh, s. k., meshram, c., deo, r. c., & ambade, b. (2018). statistical evaluation of rainfall time series in concurrence with agriculture and water resources of ken river basin, central india (1901–2010). theoretical and applied climatology, 134(3-4), 1231-1243. doi:10.1007/s00704-017-2335-y. muthoni, f. k., odongo, v. o., ochieng, j., mugalavai, e. m., mourice, s. k., hoeschezeledon, i., . . . bekunda, m. (2019). long-term spatial-temporal trends and variability of rainfall over eastern and southern africa. theoretical and applied climatology, 137(3-4), 1869-1882. doi:10.1007/s00704-018-2712-1. nimet (2008). nigeria climate review bulletin 2007. lagos: nigerian meteorological agency. nimet (2012). nigeria climate review bulletin 2012. lagos : nigerian meteorological agency. odekunle, t. o. (2004). rainfall and the length of the growing season in nigeria. international journal of climatology: a journal of the royal meteorological society, 24(4), 467-479. olaniyan, e., adefisan, e. a., balogun, a. a., & lawal, k. a. (2019). the influence of global climate drivers on monsoon onset variability in nigeria using s2s models. modeling earth systems and environment, 5(4), 1405-1428. doi:10.1007/s40808-019-00606-x. onakomaiya, s. o. (2000). ogun state: local and regional perspectives. centre for sandwich programmes (cesap), olabisi onabanjo university. oyewo o.p. (2005). trend in rainfall in northern nigeria. thesis university of ilorin, nigeria. pp. 6-19. sharma, p. j., loliyana, v. d., resmi, s. r., timbadiya, p. v., & patel, p. l. (2018). spatiotemporal trends in extreme rainfall and temperature indices over upper tapi basin, india. theoretical and applied climatology, 134(3-4), 1329-1354. doi:10.1007/s00704-017-2343-y. strahler, a.h & strahler, a.n (1988). modern physical geography, publication: john wiley & sons, inc, new york, u.s. pp. 45-82. tarfa, p. y., ayuba, h. k., onyeneke, r. u., idris, n., nwajiuba, c. a., & igberi, c. o. (2019). climate change perception and adaptation in nigeria’s guinea savanna: 249 e.a. adeleke and e.a. orebayo et al / geosi vol 5 no 2 (2020) 226-249 empirical evidence from farmers in nasarawa state, nigeria. applied ecology and environmental research, 17(3), 7085-7111. doi:10.15666/aeer/1703_70857112. tesfaye, s., birhane, e., leijnse, t., & van der zee, s. e. a. t. m. (2017). climatic controls of ecohydrological responses in the highlands of northern ethiopia. science of the total environment, 609, 77-91. doi:10.1016/j.scitotenv.2017.07.138. umar, d. a., ramli, m. f., aris, a. z., jamil, n. r., & aderemi, a. a. (2019). evidence of climate variability from rainfall and temperature fluctuations in semi-arid region of the tropics. atmospheric research, 224, 52-64. doi:10.1016/j.atmosres.2019.03.023. walter, m. w. (1967). length of the rainy season in nigeria. the nigerian geographical journal, 10(2), 123-128. vellinga, m., arribas, a., & graham, r. (2013). seasonal forecasts for regional onset of the west african monsoon. climate dynamics, 40(11-12), 3047-3070. yacoub, e., & tayfur, g. (2020). spatial and temporal of variation of meteorological drought and precipitation trend analysis over whole mauritania. journal of african earth sciences, 163 doi:10.1016/j.jafrearsci.2020.103761. zhang, w., & zhou, t. (2019). significant increases in extreme precipitation and the associations with global warming over the global land monsoon regions. journal of climate, 32(24), 8465-8488. doi:10.1175/jcli-d-18-0662.1. zhang, y., & fueglistaler, s. (2019). mechanism for increasing tropical rainfall unevenness with global warming. geophysical research letters, 46(24), 1483614843. doi:10.1029/2019gl086058. 303 evaluation of groundwater resources in aiyar basin: a gis approach for agricultural planning and development k. balasubramani 1 , m. gomathi 2, k. kumaraswamy 2* 1 school of earth sciences, central university of tamil nadu, cutn bridge neelakudy, tamil nadu, 610005, india 2 department of geography, bharathidasan university, palkalaiperur, tiruchirappalli, tamil nadu, 620024, india *corresponding author: kkumargeo@gmail.com received 19 december 2019/ revised 26 december 2019/ accepted 28 december 2019/ published 30 december 2019 abstract groundwater is an integral part of agriculture and rural development. in the present study, an attempt has been made to analyse the spatio-temporal variations of groundwater level in aiyar basin using spatial statistics and gis to associate the variations with cropping pattern; to suggest agricultural planning and development practices. the groundwater level was measured in the basin through 40 dug wells in july (premonsoon) and january (post-monsoon) besides water level data collected from 50 permanent monitoring wells for thirty-six years (1980-2015) from the state groundwater division for spatial and statistical analyses. in order to understand the fluctuations in the groundwater level of the basin, seasonal groundwater levels were computed for pre and post-monsoon seasons. to understand the regional variations in water level fluctuations, hot spot analysis is carried out using getis-ord gi* statistics in gis. based on z-score, the basin is divided into five clusters. the long-term fluctuation of groundwater level in each cluster was examined independently and the trends were determined. based on the trend of groundwater level and cropping pattern of the clusters, suggestions are drawn for each cluster for agricultural planning and development. by comparing the clusters, it is found that the foot of kollimalai and pachamalai hills (cluster4 and 5) experiences a severe drop in groundwater level. during the last 36 years, the water table of these clusters is decreased from 4 m to 10 m bgl and the rate of decline is very severe after the drought years of 2002-2003. the main reason for the declining water level in this region is the cultivation of wet crops especially paddy and sugarcane in extensive areas, although irrigation facilities are limited and the climate is conducive only for rainfed agriculture. hence, it is necessitated to reduce the acreage of wet crops and compensate by suitable dry crops in these clusters. keywords: groundwater, agriculture, gis, hot spot analysis, river basin, sdg 1. introduction groundwater resources have provided an invaluable source of irrigation to the crops but widespread and largely unregulated groundwater withdrawals by agriculture have resulted in depletion and degradation of some of the world’s most accessible and high-quality aquifers (fao, 2011). currently, agriculture uses 11 per cent of the world's land surface for crop production but accounts for 70 per cent of all water withdrawn from aquifers, streams and lakes (fao, 2016). the rapid rate of growth in irrigation is perhaps best illustrated in india, where the amount of land irrigated by surface water has doubled between 1950 and 2000, but the area irrigated from aquifers has increased by 113 times during the same period (morris et al., 2003). an increasing practice of irrigated agriculture using groundwater resources in india has already created a problem of salinization (singh, 2018). now, the groundwater shortage and groundwater quality deterioration geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.4 no. 3 (2019), 302-310, december, 2019 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v4i3.14954 accredited by the ministry of research, technology and higher education of the republic of indonesia, no. 30/e/kpt/2019. 302 303 k. balasubramani et al / geosi vol 4 no 3 (2019) 302-310 are the most common problems in irrigated agricultural areas (nachtergaele et al., 2011). the condition of groundwater resources is becoming more and more critical in the arid and semi-arid lands of the country (gupta and sharma, 2018). although agricultural production of semi-arid lands is increased steadily, groundwater extraction for irrigated agriculture in semi-arid lands has had negative effects on natural resources which become a serious threat to the food security of the country (bindraban et al., 2012). in order to satisfy human needs as well as sustaining natural resources and ecosystems, it is necessary to regulate farming systems and introduce conservation schemes preferably at a basin scale through a systematic hydrological assessment. monitoring of the groundwater level of observation wells is the principal source of information on the effects of hydrologic stresses on groundwater systems (ahmadi and sedghamiz, 2007). further, understanding the spatial pattern of groundwater level and its long-term trends are essential for making any management decision for agricultural development (reghunath et al., 2005). in recent years, several studies have reported that there are large variations in groundwater levels over many parts of india, suggesting a detailed study needs to be undertaken to elucidate the behaviour of groundwater level fluctuations in both, spatial and temporal scales for proper agricultural planning and development (anbazhagan and ramasamy, 2005; kumar et al., 2007; sivasankar et al., 2013; buvaneshwari et al., 2017). with this background, the present study attempts to assess the spatio-temporal dynamics of groundwater level in aiyar basin through gis and geostatistical modelling towards suggesting strategies for sustainable agriculture development. figure 1. base map of the study area along with its location in india 303 303 k. balasubramani et al / geosi vol 4 no 3 (2019) 302-310 the river aiyar is the major sub-basin of the middle part of the cauvery basin, tamil nadu (figure 1). the total area of the basin is 1,360 sq.km, of which about 25 per cent of the basin is covered by hilly terrain (pachamalai in the northeast and kollimalai in the northwest). the basin is mainly drained by seasonal tributaries of the river cauvery. the physical and socio-economic characteristics indicate that aiyar basin is dominated by agricultural activities and abode for four lakh rural population. the average annual rainfall for the basin is 758 mm that is gradual decreases from northern uplands to southern plains, following the general slope of the basin. the basin receives about 82 per cent of its rainfall during southwest and northeast monsoon seasons (october december) with a long dry season during remaining months. even though the basin is climatologically disadvantaged, about 70 per cent of the basin area is utilised for agricultural purposes with the help of groundwater resources. however, over a past three decades it is noticed that the average proportion of agricultural labours to the total population is in the decreasing phase (gomathi and kumaraswamy, 2016). therefore, it is pertinent to assess the potentials and dynamics of groundwater resources for suggesting suitable agricultural development measures in the basin. 2. methods in this study, seasonal groundwater levels (pre-monsoon and post-monsoon) were measured in 40 open wells across the study area during 2014-16. in order to understand the long-term fluctuations in groundwater levels, data of 36 years (1980-2015) recorded at 50 observation wells were collected from the state ground and surface water resources and development centre, chennai. the spatial pattern of groundwater level was analysed for the two seasons such as pre-monsoon (july) and post-monsoon (january) during 2014-16. the difference of water levels between pre-monsoon and post-monsoon was computed to infer the fluctuations in groundwater level and associated impacts on cropping pattern. to estimate the longterm trend of groundwater level, the average values of water level was calculated for each year. kriging interpolation technique was used to estimate the values for unknown locations. to understand the spatial variations in long-term fluctuations of groundwater level, getis-ord gi* statistic (hot-spot analysis) was computed for 90 observation wells to identify the different clusters of groundwater levels. the hot spot analysis tool in arcgis was used to calculate the statistic. this statistic identifies the clustering of high and low values based on z-score and p-value (mitchell, 2005). both z-scores and p-values are associated with the standard normal distribution of the water level data where the p-value is a probability that the observed spatial pattern was created by some random process and z-scores are simply standard deviations. statistically, the larger the positive z-score represents more clustering of high values (hot spot) where the depth to water level is deep and surrounded by well locations with deeper water levels. similarly, the negative z-score represents the clustering of shallow water levels (cold spot). the long-term fluctuation in the water level of each cluster was examined independently based on groundwater level data of respective wells for 36 years (1980-2015). the plateau region of kolli hills is identified with cold spot (shallow water level) but due to lack of long-term water level data (no monitoring wells established by groundwater division), the area was excluded from the present analysis. the agricultural data (g-return) pertaining to 130 revenue villages of the basin were also collected from district statistical offices for the period between 2010-11 and 2015-16. the location quotient method of bhatia (1965) and crop diversification method of gibbs and martin (1962) were used respectively to determine crop concentration and crop diversification of the basin. geographic information system (gis) was used to analyse and integrate the results of cropping pattern with groundwater resources and to prepare thematic maps. 304 303 k. balasubramani et al / geosi vol 4 no 3 (2019) 302-310 3. results and discussion 3.1 spatial pattern of groundwater level the groundwater level is an important variable as it indicates indirectly the groundwater potential zones, especially in the semi-arid regions (balasubramani, 2018). the groundwater level mainly depends upon rainfall, subsurface lithology and weathering. during the pre-monsoon season (july), the depth to groundwater level in the basin is found to vary from 1.8 to 29.1 m from the ground surface. due to the natural recharge of groundwater during the rainfall period (september december), the water level increases throughout the basin and varies from 1.3 to 25.8 m during the post-monsoon season (january). the groundwater levels in the study area are classified into five categories viz., <8 m (shallow), 8 – 12 m (shallow-moderate), 12 – 16 m (moderate), 16 – 20 m (deep) and >20 m (very deep). the results reveal that 30 per cent of the wells fall under very deep groundwater level category and 17 per cent of the wells fall under shallow category during the pre-monsoon period. during post-monsoon season, the condition of very deep and shallow water levels is almost reverse where 29 per cent of the wells fall under shallow and 16 per cent of the wells are observed with very deep groundwater levels. the rise of water table level in january might be the direct effect of aquifer recharge in the preceding months, especially the northeast monsoon season. figure 2. depth to groundwater level during pre and post monsoon seasons the interpolated groundwater level surface shows the spatial pattern of groundwater level for pre and post monsoon seasons (figure 2). it is inferred that the groundwater flow direction of the study area is from north to south. the water level is deeper in relatively elevated areas especially along the foot of pachamalai hills (northeastern parts) and shallower in southern plain surfaces. the plateau region of kollimalai hills is marked with isolated shallow groundwater levels. while comparing the groundwater level of post-monsoon with pre-monsoon, north-eastern parts of the study area are experiencing increased groundwater level drop 305 303 k. balasubramani et al / geosi vol 4 no 3 (2019) 302-310 and it shows that more attention should be paid to cropping pattern of these areas to prevent further degradation of groundwater potential. the seasonal water level fluctuation varies from 0 to 9.3 m. more than one-third of the wells have reported a higher level of groundwater fluctuation (> 3m). the north-eastern part of the basin is more vulnerable to groundwater fluctuation as about 60 per cent of the wells located in this region express groundwater fluctuation of more than 4 m. since a very deep water table as well as higher fluctuation is observed in the north-eastern foothills, this area requires better groundwater management practices for sustainable agricultural production. 3.2 temporal pattern of groundwater level the rise and fall of groundwater level directly depend on the rainfall pattern of a year, whether it is above or below the normal. a continued increase of extraction without adequate recharge in the aquifers will lead to the downward pull of the groundwater level over years (balasubramani et al., 2019). in order to understand the long-term fluctuations, monthly water level data of 50 monitoring wells for the period were used. the hydrograph of the basin prepared using data of monitoring wells of the basin between 1980 and 2015 shows that there is a cyclic trend of groundwater level depending upon the rainfall pattern of the basin (figure 3). however, the gap between trends in rainfall and groundwater level is widening in recent years. in 2000, the average depth to groundwater level of the basin is 5.5 m and it has declined to 13 m in 2015 with a rate of 0.5 m of lowering of water table per year (figure 4). the main reason inferred for such a declining level of groundwater in this region is the overexploitation of groundwater mainly for irrigation purposes. figure 3. hydrographs based on average water levels of monitoring wells of the study area (1980-2015) 306 303 k. balasubramani et al / geosi vol 4 no 3 (2019) 302-310 and it shows that more attention should be paid to cropping pattern of these areas to prevent further degradation of groundwater potential. the seasonal water level fluctuation varies from 0 to 9.3 m. more than one-third of the wells have reported a higher level of groundwater fluctuation (> 3m). the north-eastern part of the basin is more vulnerable to groundwater fluctuation as about 60 per cent of the wells located in this region express groundwater fluctuation of more than 4 m. since a very deep water table as well as higher fluctuation is observed in the north-eastern foothills, this area requires better groundwater management practices for sustainable agricultural production. 3.2 temporal pattern of groundwater level the rise and fall of groundwater level directly depend on the rainfall pattern of a year, whether it is above or below the normal. a continued increase of extraction without adequate recharge in the aquifers will lead to the downward pull of the groundwater level over years (balasubramani et al., 2019). in order to understand the long-term fluctuations, monthly water level data of 50 monitoring wells for the period were used. the hydrograph of the basin prepared using data of monitoring wells of the basin between 1980 and 2015 shows that there is a cyclic trend of groundwater level depending upon the rainfall pattern of the basin (figure 3). however, the gap between trends in rainfall and groundwater level is widening in recent years. in 2000, the average depth to groundwater level of the basin is 5.5 m and it has declined to 13 m in 2015 with a rate of 0.5 m of lowering of water table per year (figure 4). the main reason inferred for such a declining level of groundwater in this region is the overexploitation of groundwater mainly for irrigation purposes. figure 3. hydrographs based on average water levels of monitoring wells of the study area (1980-2015) 306 303 k. balasubramani et al / geosi vol 4 no 3 (2019) 302-310 and it shows that more attention should be paid to cropping pattern of these areas to prevent further degradation of groundwater potential. the seasonal water level fluctuation varies from 0 to 9.3 m. more than one-third of the wells have reported a higher level of groundwater fluctuation (> 3m). the north-eastern part of the basin is more vulnerable to groundwater fluctuation as about 60 per cent of the wells located in this region express groundwater fluctuation of more than 4 m. since a very deep water table as well as higher fluctuation is observed in the north-eastern foothills, this area requires better groundwater management practices for sustainable agricultural production. 3.2 temporal pattern of groundwater level the rise and fall of groundwater level directly depend on the rainfall pattern of a year, whether it is above or below the normal. a continued increase of extraction without adequate recharge in the aquifers will lead to the downward pull of the groundwater level over years (balasubramani et al., 2019). in order to understand the long-term fluctuations, monthly water level data of 50 monitoring wells for the period were used. the hydrograph of the basin prepared using data of monitoring wells of the basin between 1980 and 2015 shows that there is a cyclic trend of groundwater level depending upon the rainfall pattern of the basin (figure 3). however, the gap between trends in rainfall and groundwater level is widening in recent years. in 2000, the average depth to groundwater level of the basin is 5.5 m and it has declined to 13 m in 2015 with a rate of 0.5 m of lowering of water table per year (figure 4). the main reason inferred for such a declining level of groundwater in this region is the overexploitation of groundwater mainly for irrigation purposes. figure 3. hydrographs based on average water levels of monitoring wells of the study area (1980-2015) 306 303 k. balasubramani et al / geosi vol 4 no 3 (2019) 302-310 figure 4. trend of average water levels (2000-2015) 3.3 regional variations in trends based on z-score of the hotspot analysis, the study area is divided into five clusters namely cluster-1 (< -2.0), cluster-2 (-2.0 to -1.0), cluster-3 (-1.0 to 1.0), cluster-4 (1.0 to 2.0) and cluster-5 (> 2.0). the cluster-1 is formed in the southern flood plains where the water level is shallow and cluster-2 is formed parallel to cluster-1 on the northern side (figure 5). the clusters-4 and-5 are formed in the foot of kollimalai and pachamalai hills respectively where groundwater levels are deeper. the central portion of the study area is identified with cluster-3. the long-term fluctuation and trend in water level for each cluster was computed and shows that the average depth to the water level in cluster-1 is 6.7 m and the standard deviation is 1.2 m. since the observation wells of this region show a limited fluctuation of water level over 36 years, there is no significant change in water level. it is understood that the aquifer system of cluster-1 has relatively similar characteristics throughout the plain and has good groundwater recharge potential for wet crop cultivation practices. the average depth to the water level in cluster-2 is 9.7 m which is higher than cluster-1 and the standard deviation is 3 m. the cluster-2 has experienced a cyclic trend of water level where the period 19801991 experienced a drop in water level below the average and the period 1991-2003 observed with the rise of water level above the average. after 2003, the water level in the region is highly fluctuating and it closely depends on the rainfall pattern of the region. in general, the cluster-2 is suitable for wet crops during wet monsoon years. since the cluster-3 is dominantly covered by pediments, the average depth to the water level of this region is reported as 14 m with a standard deviation of 2.9 m. similar to cluster-2, this region is also experienced a cyclic trend of water level, but the overall trend shows a decline in water level from 13 m to 15 m. hence, the present cropping pattern should be monitored and regulated. 307 303 k. balasubramani et al / geosi vol 4 no 3 (2019) 302-310 figure 4. trend of average water levels (2000-2015) 3.3 regional variations in trends based on z-score of the hotspot analysis, the study area is divided into five clusters namely cluster-1 (< -2.0), cluster-2 (-2.0 to -1.0), cluster-3 (-1.0 to 1.0), cluster-4 (1.0 to 2.0) and cluster-5 (> 2.0). the cluster-1 is formed in the southern flood plains where the water level is shallow and cluster-2 is formed parallel to cluster-1 on the northern side (figure 5). the clusters-4 and-5 are formed in the foot of kollimalai and pachamalai hills respectively where groundwater levels are deeper. the central portion of the study area is identified with cluster-3. the long-term fluctuation and trend in water level for each cluster was computed and shows that the average depth to the water level in cluster-1 is 6.7 m and the standard deviation is 1.2 m. since the observation wells of this region show a limited fluctuation of water level over 36 years, there is no significant change in water level. it is understood that the aquifer system of cluster-1 has relatively similar characteristics throughout the plain and has good groundwater recharge potential for wet crop cultivation practices. the average depth to the water level in cluster-2 is 9.7 m which is higher than cluster-1 and the standard deviation is 3 m. the cluster-2 has experienced a cyclic trend of water level where the period 19801991 experienced a drop in water level below the average and the period 1991-2003 observed with the rise of water level above the average. after 2003, the water level in the region is highly fluctuating and it closely depends on the rainfall pattern of the region. in general, the cluster-2 is suitable for wet crops during wet monsoon years. since the cluster-3 is dominantly covered by pediments, the average depth to the water level of this region is reported as 14 m with a standard deviation of 2.9 m. similar to cluster-2, this region is also experienced a cyclic trend of water level, but the overall trend shows a decline in water level from 13 m to 15 m. hence, the present cropping pattern should be monitored and regulated. 307 303 k. balasubramani et al / geosi vol 4 no 3 (2019) 302-310 figure 4. trend of average water levels (2000-2015) 3.3 regional variations in trends based on z-score of the hotspot analysis, the study area is divided into five clusters namely cluster-1 (< -2.0), cluster-2 (-2.0 to -1.0), cluster-3 (-1.0 to 1.0), cluster-4 (1.0 to 2.0) and cluster-5 (> 2.0). the cluster-1 is formed in the southern flood plains where the water level is shallow and cluster-2 is formed parallel to cluster-1 on the northern side (figure 5). the clusters-4 and-5 are formed in the foot of kollimalai and pachamalai hills respectively where groundwater levels are deeper. the central portion of the study area is identified with cluster-3. the long-term fluctuation and trend in water level for each cluster was computed and shows that the average depth to the water level in cluster-1 is 6.7 m and the standard deviation is 1.2 m. since the observation wells of this region show a limited fluctuation of water level over 36 years, there is no significant change in water level. it is understood that the aquifer system of cluster-1 has relatively similar characteristics throughout the plain and has good groundwater recharge potential for wet crop cultivation practices. the average depth to the water level in cluster-2 is 9.7 m which is higher than cluster-1 and the standard deviation is 3 m. the cluster-2 has experienced a cyclic trend of water level where the period 19801991 experienced a drop in water level below the average and the period 1991-2003 observed with the rise of water level above the average. after 2003, the water level in the region is highly fluctuating and it closely depends on the rainfall pattern of the region. in general, the cluster-2 is suitable for wet crops during wet monsoon years. since the cluster-3 is dominantly covered by pediments, the average depth to the water level of this region is reported as 14 m with a standard deviation of 2.9 m. similar to cluster-2, this region is also experienced a cyclic trend of water level, but the overall trend shows a decline in water level from 13 m to 15 m. hence, the present cropping pattern should be monitored and regulated. 307 303 k. balasubramani et al / geosi vol 4 no 3 (2019) 302-310 figure 5. clusters of groundwater wells it is found that the foot of kollimalai hills (cluster-4) experiences a severe drop in groundwater level with a rate of 0.2 m per year. during the last 36 years, the water table of this cluster is decreased from 4 m to 10 m and the rate of decline is severe after the drought years of 2002-2003. because the average water level between 1980 and 2001 was 5.4 m and it has been doubled during the last 15 years (10.4 m). the deviation of water level from the long-term average is also higher in this cluster (3.4 m). the main reason for the declining water level in this region is the cultivation of wet crops especially paddy and sugarcane in extensive areas. the water level in the north-eastern parts of the basin (foothills of pachamalai) is deeper and statistically termed as a hot spot. the average water level of this region is 10.5 m with a standard deviation of 2.9 m. even though the long-term data of water level signifies a positive trend, the area was frequently 308 303 k. balasubramani et al / geosi vol 4 no 3 (2019) 302-310 identified with a cone of depression in the water table. the periods 1988-90, 1995-97, 2003-05 and 2013-15 are marked with a cone of depression patterns due to failure of rainfall during 1988-90, 1995, 2002 and 2011-13. this indicates that the supply of water (recharge) is slow and but extraction of groundwater is rapid and alarming. the geochemical analysis of water samples shows that the classes of poor groundwater i.e. very high salinity hazard and moderate sodium hazard are also mainly found in the cluster-5. 3.4 cropping pattern of the basin paddy and sorghum are first ranking crops over extensive parts of the basin comprising about 75 per cent of the villages. the recent distributional pattern of the dominance of these two crops reflects differences in the availability of groundwater resources. the high concentration of maize and cotton occurs mainly in the north-eastern parts of the basin and proves that the groundwater resource of this region is depleted in recent years. the diversification index value of the basin is 0.88 represents a very high crop diversification as a whole. the areas of very high crop diversification found in the foothills region, especially in north-eastern foothills, indicate that the groundwater exploitation in cluster-5 is abnormal. 4. conclusion groundwater is the basis for almost all kinds of human activities in the basin. the spatial pattern of groundwater level shows that the foot of pachamalai (north-eastern part) has very deep water table with marked seasonal fluctuations and cone of depressions. the temporal pattern of groundwater level signifies that the foot of kolli hills (north-western part) has a significant decline of groundwater level in the last two decades. at the same time, the cropping pattern of these regions is still water-intensive and highly depends on open and bore wells. therefore, conversion of wet cropping system to dry crops and implementation of water harvesting systems such as recharge wells, percolation ponds and check dams in northern parts are strongly suggested for sustainable development of agriculture in the basin. conflict of interest the authors declare that there is no conflict of interest with any financial organization regarding the material discussed in the article. references ahmadi, s. h., sedghamiz, a., (2000). geostatistical analysis of spatial and temporal variations of groundwater level. environment monitoring and assessment, 129:277–294. http://dx.doi.org/10.1007/s10661-006-9361-z anbazhagan, s., ramasamy, s.m., (2005). evaluation of areas for artificial groundwater recharge in ayyar basin, tamil nadu, india through statistical terrain analysis. journal geological society of india, 67(1):59-68. balasubramani, k., (2018). physical resources assessment in a semi-arid watershed: an integrated methodology for sustainable land use planning. isprs journal of photogrammetry and remote sensing 142:358–379. https://doi.org/10.1016/j.isprsjprs.2018.03.008 balasubramani, k., rutharvel murthy, k., gomathi, m., kumaraswamy, k., (2019). integrated assessment of groundwater resources in a semi-arid watershed of south india: implications for irrigated agriculture. geojournal, 1-23 https://doi.org/10.1007/s10708-019-10050-0 309 303 k. balasubramani et al / geosi vol 4 no 3 (2019) 302-310 bindraban, p.s. marijnvan der v., limingye, et al., (2012). assessing the impact of soil degradation on food production. current opinion in environmental sustainability, 4(5): 478-488 https://doi.org/10.1016/j.cosust.2012.09.015 buvaneshwari, s. riotte, j., ruiz, l. et al., (2017). impacts of land-use and soil properties on groundwater quality in the hard rock aquifer of an irrigated catchment: the berambadi (southern india). in proceedings of 19th egu general assembly, vienna. fao, (2011). the state of the world’s land and water resources for food and agriculture managing systems at risk. food and agricultural organization, rome. http://www.fao.org/docrep/017/i1688e/i1688e.pdf (15 november 2019) fao, (2016). land degradation assessment in drylands manual for local level assessment of land degradation and sustainable land management part-1. food and agricultural organization, rome http://www.fao.org/ publications/card/en/c/40875549-ecc8-4388-b944-26edc9b58272 (15 november 2019) gomathi, m. and kumaraswamy, k., (2016). patterns of crop concentration and diversification in aiyar basin, central tamil nadu. punjab geographer, 12:97-112. gupta, p.k., sharma, d., (2018). assessment of hydrological and hydrochemical vulnerability of groundwater in semi-arid region of rajasthan, india. sustainable water resources management, 5:847–861 https://doi.org/10.1007/s40899-018-0260-6 kumar, m., kumari, k., ramanathan, a. et al., (2007). a comparative evaluation of groundwater suitability for irrigation and drinking purposes in two intensively cultivated districts of punjab, india. environmental geology, 53:553-574. https://doi.org/10.1007/s00254-007-0672-3 mitchell, a., (2005). the esri guide to gis analysis, volume 2. esri press, red lands. morris, b.l., lawrence, a.r.l., chilton, p.j.c., adams, b., calow r.c., klinck, b.a., (2003). groundwater and its susceptibility to degradation: a global assessment of the problem and options for management. early warning and assessment report series, rs. 03-3. united nations environment programme, nairobi. nachtergaele, f. biancalani, r., petri, m., (2011). land degradation. solaw background thematic report 3. food and agricultural organization, rome http://www.fao.org/nr/solaw/thematic-reports/en/ (15 november 2019) reghunath, r., sreedhara murthy, t. r., raghavan, b. r., (2005). time series analysis to monitor and assess water resources: a moving average approach. environmental monitoring and assessment, 109:65–72. singh, a., (2018). managing the environmental problems of irrigated agriculture through the appraisal of groundwater recharge. ecological indicators, 92:388-393 https://doi.org/10.1016/j.ecolind.2017.11.065 sivasankar, v., ramachandramoorthy, t., chandramohan, a., (2013). deterioration of coastal groundwater quality in island and mainland regions of ramanathapuram district, southern india. environmental monitoring and assessment, 185(1):931-944 https://doi.org/10.1007/s10661-012-2604-2 310 upang septa putra and muhsinatun siasah masruri/ geosi vol 4 no 2 (2019) 146-163 146 the effectiveness comparison between inquiry and problem based learning towards geography learning outcomes upang septa putra1* and muhsinatun siasah masruri1 1master program of geography education, yogyakarta state university, indonesia *email : upangsepta94@gmail.com received 5 may 2019/ revised 5 july 2019/ accepted 16 july 2019/ published 20 august 2019 abstract this study aims to determine the differences of learning outcomes between students that were performed using inquiry and student who were applied using problem based learning in classes of x sma 2 plakat tinggi. this study also purposes to examine the effectiveness comparison between problem based learning and inquiry method. the research engages quantitative research with quasi-experimental type. subject selection conducts match design. the population of this study were students of class x ips in sma 2 plakat tinggi which composed of three classes. the sample selection in this study engaged purposive sampling, hereby x ips 3 was elected as experimental group 1 (problem based learning) and class x ips 1 as the experimental group 2 (inquiry) class. data collection technique performed in this study was learning outcomes in the form of written test. data analysis technique was engaging independent sample t-test, which was followed by n increased and effect size extent. the findings are differences of learning outcomes improvement between students who studied utilizing inquiry method and students who were taught using problem based learning method. problem based learning is more effective than inquiry in promoting geography learning outcomes. this is indicated through calculation result upon effect size extent, where students who were taught using problem based learning method obtain a value of 4.185, larger compared to those who were treated using inquiry method which obtain a value of 3.462. keywords: inquiry, problem based learning, geography 1. introduction the rapid development in the sense of education is increasingly improved and this developing condition requires students capacity in mastering comprehensive the subjects matter of school, especially on geography subject. since, within geography subject students are not only provided the content in the form of theory, but also directly examine geographycontent on daily basis. sumaatmadja (2001: 12) argues that geography learning is geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.4 no. 2 (2019), 146-163, august, 2019 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v4i2.10849 doi : 10.19184/geosi.v4i2.10192 upang septa putra and muhsinatun siasah masruri/ geosi vol 4 no 2 (2019) 146-163 147 essentially an image of spatial aspects of the earth surface, which is the whole symptom of nature and human life upon regional variations. in addition, during geography learning students are compulsory to investigate all human activities that are closely related to the surrounding environment, namely: atmosphere, lithosphere, hydrosphere and biosphere. the presence of geography learning is expected to establish and develop students understanding of variation and spatial organization between communities within residence and the environment on earth surface. geography obtains original features, namely thinking process, in which geography examines things or symptoms that have interdependent relationships between one symptom to another. futhermore, there is geographical manner of thinking which needs an analysis of a concrete object relationship and symptoms, whose spatial relations can be captured by the five senses. however, students were not adequately interested in geography learning, since students considered geography subject as unattractive subject which was determined through observations conducted at sma 2 plakat tinggi.when the learning process occured in the classroom, students have not been actively involved in the learning process. this fact could be observe daccording to students participation during the learning process which tended to be insufficient and passive. for instance, when teacher presented questions to students, there were only one or two students who were able to complete the answers. students behavior who have not been actively involved in geography subjects was certainly determined by several factors, both internal and external. internal factors are namely; student attitudes toward learning which was tend to be conventional, as well as insufficient interest and motivation. while external factors, for example, were related to the application of learning methods that were monotonous. most learning methods engaged at sma 2 are conventional namely coursework/lecture method and assignment completion. hence, during learning process students were basically uniterested and became bored quickly. inorder to cope all the issues, teacher must be able to arrange, design and implement effective and efficient learning. thus, it is expected to enhance students motivated during learning process and improve learning outcomes as well. futhermore, in order to provide students learning motivation, of course an appropriate learning method is required. learning method is a method engaged to implement plans that have been prepared, in the form of real and practical activities to achieve the learning objectives referring suprijono (2015: 50). utilizing suitable learning method could generate easier manner for students to understand geographic subjects that will affect improvement of student learning outcomes. there are several learning methods that can be engaged towards geography learning process namely; upang septa putra and muhsinatun siasah masruri/ geosi vol 4 no 2 (2019) 146-163 148 inquiry-based learning methods, discovery-based learning (discovery), problem-based learning (problem based learning), and project-based learning (project based learning). however, considering all the method provided, there are two the most appropriate methods to be utilizied, namely inquiry based learning and problem based learning. utilizing both methods allowing students more convenience to embrace thecontents that is directly related to the real life, including the symptom or phenomena and problems that prevails in daily life and capable in improving the value of optimal learning outcomes. alberta (2004: 1) mentions during inquiry based learning processes students are participating on to learning, formulate questions, learn comprehensively and then build new understandings, meanings and knowledge. this assumption can be interpreted that inquiry based learning (ibl) is a learning process where students are involved within formulating questions that lead to conduct investigations in an effort to construct new knowledge and meanings. inquiry process is a stage of promoting problems, obtaining information, thinking creatively in possible solutions, making decisions and arranging conclusions based existing problems. in contrary, compared to what was stated earlier, duran & dokme (2016: 2889) convinced that inquiry based learning can be defined as a learning approach in encouraging students to be active throughout the learning process, enhancing their scientific processsuitable to skills, and improving critical-thinking skills through discussions and activities. this statement is strongly associate towards opinion expressed by unver & sertac (2011: 304) argues that inquiry based learning is a learning activity that refers to student activities, where students allow to develop knowledge and understanding of scientific ideas, as well as understanding how scientists figure out about the world. increasing knowledge and understanding as well as scientific ideas gained by students, especially for subjects which are expected to improve geography learning outcomes. inquiry based learning explanation above relates to mundilarto's research (2013: 256) which concludes that inquiry approach is more effective in improving student learning outcomes compared to the conventional approaches. basically, inquiry method characteristics according to smith & walker (2010: 27) are; (a) learning is stimulated by inquiry, it is established by questions or problems, (b) learning is based on a process of constructing knowledge and new insight, (c) an active approach to learning, involves learning by doing, a student-centered approach to teaching in which the role of the teacher is a facilitator (d) anaction to self-directed learning which students are performing high responsibility upon their learning. inquiry method learning stages according to blessinger & john (2014: 11) are: upang septa putra and muhsinatun siasah masruri/ geosi vol 4 no 2 (2019) 146-163 149 exploration, problem identification, investigation, data collection and analysis, conclusions formulation obtained based on creative communication result. inquiry learning is different compared to problem based learning (pbl). according to simone (2014: 18), problem based learning is a pedagogical approach centered on learners, whichconveys students the opportunity to engage into investigations directed towardslearning subjectives. this definition is supported by yew & karen’s result (2016: 2) that problembased learning is a pedagogical approach that enables students to learn while engaging actively with problems, this is different towards previously stated,whitcombe (2013: 41) convinces that problem-based method learning attempts students the opportunity to develop skills, such as problem solving, clinical reasoning, and assist students with skills to acquire science/knowledge. regarding students skills when solving a problem, reasoning and debriefing are obtained through stages of problem-based learning method. these stages are expected to facilitate students to acquire new knowledge in order to achieve optimal learning outcomes. this matter associates towards agustini's research results (2017: 97-98) which state pbl promotes students directly in learning to dissemninate knowledge through real visualization. thereby, pbl enables improvement ofstudents learning outcomes. students during learning process within problem based learning are actively involved in preparing and communicating opinions. overall, students attitudes engaging pbl method can be consideredas active and interested in the learning process. pbl does not only improve student learning, but increases student learning outcomes problem based learning method characteristics according to barrett & moore (2010: 94-95) are: (a) the issue/problem presented must obtain more than one solution, (b) the problem must be complex, (c) the problem must be structured reasonably, (d) problem must be multidisciplinary, (e) problem concerns on teamwork, (f) problems must require ideas in problem solving, (g) problem solving requires source references, (h) problems require identification in the process learning, (i) each student or group must reflect the effectiveness of the learning solution. while, problem based learning stages according to seng (2009: 9), are featuring 5 steps as follows: (a) identifying the problem, (b) problem analyzing and learning issues formulating, (c) discovering and reporting, (d) presenting solution and reflecting, (e) and ovierview, integrating and evaluating. contrary tothe seng’s,yuniwati (2016: 17) explains the steps of problem-based learning namely: (a) identifying a problem and examining relevant information sources, (b) independent learning (self directed learning), (c) investigating a problem and performing interpretation, (d) establishing several alternative upang septa putra and muhsinatun siasah masruri/ geosi vol 4 no 2 (2019) 146-163 150 solutions to problems (high cognitive complexity), (e) integrating opinions or information data to determine problems solution, and (f) self reflecting. 2. the methods the research method used is a scientific approach to obtain data with specific objectives and uses. relating the research that would be conducted, this research is a quantitative type with a quasi-experimental approach using match subject design. research population were students of class x ips of sma 2 plakat tinggi which composed of 3 classes. then, researcher collected a sample employing a purposive sampling. hence, the sample selected was class x ips 3of 35 students as an experimental class with problem based learning method and classes x ips 1 as an experimental class using inquiry method which composedof 33 students. the data collection technique employed in this study was learning outcome in term of geography learning test with 20 multiple choice questions. the test was engaged to determine general ability before and after treatment provided. data analysis technique engaged within this research obtained two stages, namely data description stage and the hypothesis testing stage. the action performed upon data description test stage was formulating a summary of data distribution in the form of prettest and posttest using the spss 20.00 for window. while for hypothesis examination was performing independent sample t-test. data analysis regarding geography learning outcomes improvement was conducted by the n gain score. n gain score is obtained through posttest results calculation which are reduced by the prettest value in experimental classes performed inquiry and problem based learning. in calculating the n gain formula, researcher utilized the following formula: then, assessing the effectiveness of the learning method is performing by calculating the effect size (es). the formula used according to warner (2008: 202) is as follows: d = information: ez = effect size m1 = prettest mean upang septa putra and muhsinatun siasah masruri/ geosi vol 4 no 2 (2019) 146-163 151 m2 = posttest mean sp = standard posttest deviation the calculation results obtained from calculations formulated through over effect size are categorized toward criteria proposed by cohen (1988) about the level of the effect size as follows : ice ≤ 0.2 (low), 0.2 ≤ es ≤ 0.8 (moderate), and ice ≥ 0.8 (height). 3. results and discussion this research is quantitative one that applying two classes as experimental classes. learning outcomes were acquired based on two times tests, namely pretest and posttest. pretest was performed to determine thestudents initial abilities (pretest) and the final test (posttest) used to determine the ability of students after being treated with certain learning methods. 3.1 pretest results of experimental classes engaging inquiry and problem based learning description of the prettest results of student learning outcomes can be seen in table 1 as follows: table 1. description of prettest data of student geography learning outcomes no descriptive statistics results inquiry problem based learning 1 mean 44.24 46.42 2 mode 40 40 3 median 45 45 4 deviation standard 8.20 9.43 source: primary data processing (2018) based on the table, it shows that the average prettest value of students in the experimental group 1 applied using the problem based learning method obtain an average value of 46.42, mode 40, median 45 and a standard deviation of 9.43. while the average prettest value of students in the experimental group 2 applied using the inquiry method obtain an average value of 44.24, mode 40, median 45 and a standard deviation of 8.20. 3.2 posttest results of experimental classes engaging inquiry and problem based learning upang septa putra and muhsinatun siasah masruri/ geosi vol 4 no 2 (2019) 146-163 152 description of prettest data results of students learning can be seen in table 2 as follows: table 2. description of posttest data of student geography learning outcomes no descriptive statistics results inquiry problem based learning 1 mean 82.00 75.00 2 mode 80 75 3 median 80 75 4 standard deviation 8.50 9.10 source: primary data processing (2018) based on the table, it shows that the average posttest value of students in experimental group 1 applied using the problem based learning method obtain an average value of 82.00, mode 80, median 85 and standard deviation of 8.50. while, the average posttest value of students in the experimental group 2 applied using the inquiry method obtain an average value of 75.00, mode 75, median 75 and a standard deviation of 9.10. 3.3 comparison of average prettest, posttest and n gain results of geography learning outcomes student learning outcomes escalation in experimental class engaging inquiry method and problem based learning method is recognizable with comparison between prettest and posttest values figured in the gain score. based on the calculation of gain score obtain the average value of increasing student learning outcomes of experimental class treated with inquiry method is 31.51. students learning outcomes who were performed problem based learning have increased by 35.58. the gain score results of experimental class based inquiry method and problem based learning presented in table 3 below: table 3. comparison of average prettest, posttest and n gain results of geography learning outcomes no learning methods prettest posttest n gain 1 inquiry 43.18 74.69 31.51 2 problem based learning 46.42 82.00 35.58 source: primary data processing (2018) upang septa putra and muhsinatun siasah masruri/ geosi vol 4 no 2 (2019) 146-163 153 based on it table 3, it could be examined the differences of learning outcomes improvement of geography between inquiry and problem based learning within two groups. experimental group treated using inquiry method experience an incline of learning outcomes by 31.51, while the learning outcomes applying problem based learning method increases by 35.58. 3.4 first hypothesis examination table 4. statistics test of student learning outcomes using independent samples test sources: statistical results based on spss 22.00 based on the results of variance analysis calculation relating the differences of achievement upon learning outcomes between students who performed problem based learning and inquiry method with errors opportunity of (p) 0.008, it is smaller than the specified level of significance of 0.05. the output results assisted with spss 22.00 application presented in the table. it can be concluded that the value of t is equal to -2,722 with p value smaller than alpha 0.05. then h0 is rejected and ha is accepted. according to these results, it can be revealed that the null hypothesis (h0) is rejected. this means "there is a significant difference of learning outcomes intensification between students who using problem based learning method and students who learned using the inquiry method". gain score value based on calculation results between a class applied with inquiry learning and a class with problem based learning method, the percentage of the gain score in table 5 is obtained as follows: t-test for equality of means t df sig. (2tailed) mean difference geography learning results equal variances assumed -2.722 66 .008 -.10689 equal variances not assumed -2.718 65.192 .008 -.10689 upang septa putra and muhsinatun siasah masruri/ geosi vol 4 no 2 (2019) 146-163 154 table 5. percentage of gain score no learning methods test result score 1 inquiry prettest average 43.18 posttest average 74.69 gain score 31.51 % gain score 71.13 2 problem based learning prettest average 46.42 posttest average 82.00 gain score 35.58 % gain score 76.61 source: primary data processing (2018) based on the table, the gain percentage score of learning outcomes in class applied with the inquiry method is 71.13, smaller than the class applied engaging problem based learning which is 76.61. considering these data, it could be assumed that achievement upon students learning outcomes between the class applied with inquiry method and another class applied with the problem based learning method has notable differences. the two classes engaged both inquiry method and problem based learning have different learning outcomes, both pretest and posttest scores. the improvement highlight particularly emerges between posttest value and the pretest (gain score), there are prominent differences in learning outcomes (76.71>71.13). based on the study results generated, it is obvious that problem based learning enables to promote students social studies learning outcomes, since problem based learning method is an actual method and suitable within activities carried out by students in their daily lives. problem based learning method defines learning process that starts from initial stage of learning based on a problem occurs in real life. then referring to the problem, students are stimulated to examine them based on knowledge and experience they obtain previously. thereby, a new knowledge and experience will possibly formed. upang septa putra and muhsinatun siasah masruri/ geosi vol 4 no 2 (2019) 146-163 155 3.5 second hypothesis test table 6. effect size value of inquiry and problem based learning no learning methods test result score 1 inquiry prettest average 43.18 posttest average 74.69 gain score 31.51 deviation standard 9.10 effect size 3.462 2 problem based learning prettest average 46.42 posttest average 82.00 gain score 35.58 deviation standard 8.50 effect size 4.185 source: primary data processing (2018) based on the table, it can be seen that the value of the effect size on inquiry method earns a value of 3.462 which is categorized as the high category. this value is persistent towards the effect size value on problem based learning method, which also gains 4,185, that is classified as high category. according to these values, it can be concluded that problem based learning method engagement is more effective than inquiry method in term of students geographic learning outcomes of sma plakat tinggi 2. according to independent sample t-test result analysis, it shows that there are slightly differences of geography learning outcomes between students who were applied inquiry method over students who were applied problem based learning method. results of this study indicate that geography subject utilizing problem based learning method is more adequate than inquiry method. referring to students learning outcomes, presenting that student who were applied problem based learning method pose higher score than students who were performed using inquiry method. this achievement gained from statistical analysis, which is p = 0.008, smaller than the specified level of 0.05, which means significant. this result confirms that student learning outcomes based inquiry method obtain an average value of learning outcomes of 31.51, smaller comparedto problem based learning method which pose an average value of 35.58. theoretically, geography learning engages problem based learning method capable to motivate students in examining interesting problems and also challenges students to overcome a factualproblem occurs in everyday life. the similar statement is figured by upang septa putra and muhsinatun siasah masruri/ geosi vol 4 no 2 (2019) 146-163 156 wijayanti & wulandari (2016: 119) who contends that learning process within problem based learning at the beginning stage of activity motivates students to solve interesting and also challenging problems. hence, it would be more convienence for students to think at a higher level and get accustomed in solving the problems. geography learning performs problem based learning method concerned on problems utilization reinforces students to relate problems encountered in daily life. hence,students could interpret the learning material being delivered. problem solving activities within early stage of learning process provide practices and insight for students to embrace new material. a problem that does not emphasize on procedures and algorithms help students to think independently in plan making and solving problems, evaluating solutions consequences and preparing other alternative solutions. problem based learning is deliberately designed in the form of problems, thus students enable to acquire new knowledge in order to promote students proficient in solving problems, capture their own learning strategies and skills to participate in teams. the learning process performs systemic approach to solve problems or challenges needed in everyday life. futhermore, problem based learning method subjectives as follows: inaugurating flexible knowledge, developing effective problem solving skills that referring to the abilities to apply metacognitive strategies and appropriate reasoning, teachers must construct plans how learning process could achieve learning goals or not, teachers become good collaborators which, means participating effectively in small groups, assisting students to be intrinsically motivated, which usually occurs when students work on assignments for their own satisfaction, interests, or challenges (as cited in bridges et al., 2012: 3). in addition, problem based learning application is expected that students could achievesignificant knowledge and able to boost geography learning outcomes. problem based learning and inquiry method occupy different features.where problem based learning method ischaracterized of real life issues provided in daily lives of students. this is similar towards handoyono (2016: 35) that inquiry method and problem based learning have characteristics upon problem given. in which, problem within inquiry method must be identified by students themselves, whereas within problem based learning, problems are determined by teacher. thereby, problem based learning method utilization is purposed for students embracing more skills than memorizing, thinking skills, working with groups or solving problems. this is unquestionably different towards inquiry method based application that delivers assignments to students individually. hence, students tend become more occupied in performing single task in a subject. in other words, inquiry method possibly derive students become frustrated once they are unable to complete a learning process. upang septa putra and muhsinatun siasah masruri/ geosi vol 4 no 2 (2019) 146-163 157 based on the results of data analysis, it can be concluded that geography learning applied with problem based learning method is more effective in improving student learning outcomes. this result reveals through calculations results using the effect size, while problem based learning method obtains 4,185, categorized as higher category. it is larger than inquiry method which has a value of 3,462, that is categorized as high category. this also implies that students who performed problem based learning method have a posttest average value of 82.00, higher than the results of the posttest inquiry method which obtain an average score of 74.69. in general, according to mckeown et al. (2016: 2) explains that inquiry based learning is basically a question-based approach to teaching and learning that profitable for students in a number of ways including improvement and involvement in the learning process, understanding development, high-level thinking skills and research skills improvement. contrary towards what was described earlier, friesen & david (2013: 21) state that inquirybased teaching is a phenomenon that poses a challenging explanation of what they observe: devise and conduct experiments which data is collected to support or contradict their theories. within learning process using inquiry method, students are actively involved in collaborating to create a new knowledge by thinking critically and creatively and can make good discoveries through investigation, reflection, exploration and experimentation. in addition, during inquiry method students are required to be responsible for their learning. after learning process is completed, the consequences could be observed based on learning outcomes improvement. characteristics of inquiry based learning stages referring to minner et al. (2010: 476) are: (a) students are involved scientifically oriented questions, (b) students develop and evaluate every single learning outcome, (c) students allow to formulate and answer scientifically oriented questions, (d) students evaluate the problem explanation and provide alternative solutions, especially those related to scientific understanding. by engaging this indicator, makes it convenience to determine the learning process achievement extent received by students. while, the steps or syntax of inquiry-based learning process according to chu et al. (2017: 136-138) are composed of opening, immersion, exploration, identification, searching, creating and evaluating, sharing, evaluation. goodman (2018: 255) argues that problem based learning is a teaching method that encourages students active learning. basically, student work together to complete the problems. thereby, students are required to perform research and solving complex issue. problems presented of problem based learning method basically refer to contextual and upang septa putra and muhsinatun siasah masruri/ geosi vol 4 no 2 (2019) 146-163 158 authentic, that students encounter every day, whether in school or community environment. thus,students are expected to provide opportunities and determine solutions upon real life problems. problems determination upon problem based learning method have to be clear and meaningful. then students may achieve optimal learning goals, optimal learning objectives occurs along with students learning outcomes enhancement. problem based learning allows students to obtain new knowledge easier after arranging solutions towards daily life related problems. the effectiveness of problem based learning method can be noticed from students ability in performing problem solving that has been provided. thus, it is expected to promote students understanding the subject matter indaily life related problem. problem based learning method requires students to be active within solving activities. problem solving concept of pbl model is performed during group discussion. problem based learning put strong emphasis on exchanging opinions and sharing experiences. students who are highly motivated will be more interested in exploring knowledge and demanding to identify something new to solve problems related to the real world. problem based learning method is expected to improve students' creative thinking abilities in geography learning, which is based on real life problems that occur in daily life. hence, learning process will likely be much more meaningful, since students are able to formulate answers and solve problems independently. the problem provided in problem based learning is a problem related to daily life. delivering problems inactual context aims to enable students to construct their own knowledge. this is associates to trianto’s argument (2010: 67) that problem-based learning presents authentic and impressive problem situations to students, so they could provide convenience manner to conduct investigations and inquiry. through the problems given, students attempt to accomplish the problem based on students prior knowledge. then, students will possible able to find relation between the previous contentto the new one which they are performing. problems as the majorfocus of learning can be completed through team work. thereby, students are able to perform diverse learning experiences such as collaboration and interaction in groups. in addition, learning experiences related to problem solving such as formulating hypotheses, designing experiments, conducting investigations, collecting data, interpreting data data, displaying conclusions, presenting, discussing, and writing reports wijayanti & wulandari (2016: 121). this situation shows that problem based learning could implement more experience and knowledge compared to other learning methods. furthermore, problem based learning method engagement allows students to upang septa putra and muhsinatun siasah masruri/ geosi vol 4 no 2 (2019) 146-163 159 increase their understanding of what they learn in everyday life and can be applied in contextual term. the purposes of problem based learning method according to hmelo-silver (2004) are namely: constructing dynamic knowledge, developing effective problem solving skills that refer to the ability in applying metacognitive and reasoning strategies adequately, teacher ability to plan how the learning process can achieve learning goals, becoming good collaborators, which means participating effectively in small groups, supporting students to be intrinsically motivated, which occurs when students work on assignments for satisfaction, interest, or meet their own challenges (as cited in bridges et al., 2012: 3). in addition, implementation of problem based learning method within learning process is expected students achievement in term of knowledge acquisition and learning outcomes escalation. according to grady et al.(2012: 150) propose problem based learning characteristics as follows: (a) lead to learning issues, (b) interest and stimulate triggers, (c) stimulate critical reasoning, (d) promote self directed learning, (e) related to prior knowledge and (f) promote teamwork. in addition, regarding previously characteristics of problem based learning method, the learning process begins with the following steps: (a) identify a problem and explore relevant information sources, (b) independent learning (c) conduct an investigation of a problem and interpret it, (d) prioritize several alternative solutions to problems (high cognitive complexity), (e) integrate opinions or information data to determine problems solutions, (f) self-reflection (yuniawati, 2016: 17). based on problem based learning method stages could derive a significant influence in improving student learning outcomes compared to inquiry method. since, problem based learning method encourages students to recognize how to learn and cooperate in a group to determine a solution to the problems that prevails in the real world. simulation stage are conducted to activate students curiousity before starting to learn a subject. in addition, the existence of this simulation prepares students to think critically and analytically, also to acquire and perform learning resources appropriately. it can be implied that problem based learning method is a learning process which has starting point of learning based on real life problems. starts from this problem, students are stimulated to examine them according totheir knowledge and experience they had before hand. thus, students new knowledge and experience will be formed. discussion within small groups is the main point of problem based learning method implementation, as discussions would promote students exchange ideas or express opinions with each other. in addition, problem based learning method is a very effective guide in improving student learning outcomes, especially geography subject. upang septa putra and muhsinatun siasah masruri/ geosi vol 4 no 2 (2019) 146-163 160 as problem based learning (pbl) method poses many benefits compared to inquiry method, according to westwood (2008: 31) pbl offers several reasons as follows: (a) encourage self-direction in learning, (b) prepare students for critical, analytical thinking, and empower students to identify, (c) finding and using appropriate resources, (d) the problems studied are closely related to the real world. hence, it motivates students to learn, (e) promote students to be active in integrating information and skills from various scientific disciplines, knowledge and strategies tend to be restored and transferred to other learning situations, and improve the communication skills and social skills needed for teamwork and teamwork. in addition, problem based learning method poses a number of activities that must be completed for students, which expect students not only to record then memorize the subject matter, but also students are required to actively think, communicate, search and process data, and finally conclude. referring to the two learning methods, both in the form of inquiry method and problem based learning method, as well as improving student learning outcomes, both of these learning methods are able to improve student learning outcomes of geographic subject. where the calculation result of problem based learning enhances learning outcomes with average by 82.00, higher than the average value of learning outcomes applied with inquiry method which obtains a value of 74.69 4. conclusion there is a difference significant difference of learning outcomes between students who learn engaging inquiry methods and problem-based learning methods. this can be observed based on average improvement in student learning outcomes between students who were treated with learning-based method gain value of 82.00, higher than the average learning outcomes applied with inquiry method which obtains a value of 74.69. problem-based learning method is more effectively applied to geography subjects rather than inquiry method in term of improving student learning outcomes. this is indicated by calculation results of effect size, which students who were performing problem based learning method obtain value of 4.185, it is greater than the students who were applying inquiry method which obtain a value of 3.462. references agustini, d. m. (2017). pbl untuk meningkatkan hasil belajar ipa siswa tunarungu kelas iv a slbn 2 bantul. widia ortodidaktika, 6(4), 427-437. upang septa putra and muhsinatun siasah masruri/ geosi vol 4 no 2 (2019) 146-163 161 alberta. (2004). focus on inquiry: a teacher’s guide to implementing inquiry based learning. canada: learning resources centre. barret, t., & moore, s. (2010). new approaches to: problem based learning reveitalising your practice in higher education. new york: routledge. blessinger, p., & carfora, j. m. (eds.). (2014). inquiry-based learning for the arts, humanities and social sciences: a conceptual and practical resource for educators. emerald group publishing. bridges, s., mcgrath, c., & whitehill, t. l. (eds.). (2012). problem-based learning in clinical education: the next generation (vol. 8). springer science & business media. chu, s. k. w., reynolds, r. b., tavares, n. j., notari, m., & lee, c. w. y. (2017). 21st century skills development through inquiry-based learning. doi:10.1007/978981-10-2481-8 cohen j. (1988). statistical power analysis for the behavioral sciences. new york, ny: routledge academic. duran, m., & dokme, l. (2016). the effect of the inquiry based learning approach on student’s critical thinking skills. eurasia journal of mathematics, science & technology education, 12(12), 2887-2908. https://doi.org/10.12973/eurasia.2016.02311a. friesen, s., & david, s. (2013). inquiry based learning review. calgary: university of calgary. retrieved from https://www.researchgate.net/publication/312592892_inquirybased_learning_a_review_of_the_research_literature. goodman, d. (2018). problem-based learning in the mpa curiculum. journal of public affrairs education, 14(2), 253-270. retrieved from http://www.jstor.org/stable/40215813. grady, g.o., elaine h.j.y., karen, p.l.g., & henk, g.s. (2012).one day one problem an approach to problem based learning. singapore: springer. handoyono, n.a. (2016). pengaruh inquiry learning dan problem-based learning terhadap hasil belajar pkkr ditinjau dari motivasi belajar. jurnal pendidikan vokasi, 6(1). http://dx.doi.org/10.21831/jpv.v6i1.8114. hmelo-silver, c. e. (2004). problem-based learning: what and how do students learn?. educational psychology review, 16(3), 235-266. mckeown, t. r., abrams, l. m., slattum, p. w., & kirk, s. v. (2015). enhancing teacher beliefs through an inquiry-based professional development program. journal of education in science, environment and health, 2(1), 85. doi:10.21891/jeseh.30143 upang septa putra and muhsinatun siasah masruri/ geosi vol 4 no 2 (2019) 146-163 162 minner, d. d., levy, a. j., & century, j. (2010). inquiry-based science instruction-what is it and does it matter? results from a research synthesis years 1984 to 2002. journal of research in science teaching, 47(4), 474–496. doi:10.1002/tea.20347 mundilarto. (2013). keefektifan pembelajaran inquiry based learning untuk peningkatan karakter siswa pada pembelajaran fisika. jurnal cakrawala pendidikan. retrieved from https://journal.uny.ac.id/index.php/cp/article/download/1483/pdf. seng, t.o. (2009). problem based learningand creativty. singapore: cengage learning asia pte ltd. simone, c.d. (2014). problem based learning in teacher education: trajectories of change. international journal of humanities and social science, 4(12).retrieved from http://www.ijhssnet.com/journals/vol_4_no_12_october_2014/3.pdf. smith, r.s., & walker, r. (2010). can inquiry-based learning strengthen the links between teaching and disciplinary research? studies in higher education, 35(6), 723-740. https://doi.org/10.1080/03075070903315502. sumaatmadja, n. (2001). metode pengajaran geografi. jakarta: bumiaksara. suprijono, a. (2015). cooperative learning teori & aplikasi paikem. yogyakarta: pustaka pelajar trianto. (2010). model pembelajaran terpadu: konsep, strategi, dan implementasinya dalamkurikulum tingkat satuan pendidikan (ktsp). jakarta: bumi aksara. unver, a.o., & sertac, a. (2011).ovierviews on inquiry based and problem based learning methods. western anatolia journal of educational science, 303-309. retrieved from http://webb.deu.edu.tr/baed/giris/baed/ozel_sayi/303-310.pdf. warner, r.m. (2008). applied statistic. usa: sage publications. westwood, p.s. (2008).what the teacher need to know about teaching methods. camberwell, v: acer press. whitcombe s.w. (2013) problem-based learning students’ perceptions of knowledge and professional identity: occupational therapists as ‘knowers’, british journal of occupational therapy,76(1), 37-42 wijayanti, a., & wulandari, t. (2016). efektivitas model ctl dan model pbl terhadap hasil belajar ips. harmoni sosial: jurnal pendidikan ips, 3(2), 112. doi:10.21831/hsjpi.v3i2.7908 yew, e.h.j., & karen, g. (2016). problem-based learning: an overview of its process and impact on learning. journal health professions education, 2(2), 75-79. https://doi.org/10.1016/j.hpe.2016.01.004\. upang septa putra and muhsinatun siasah masruri/ geosi vol 4 no 2 (2019) 146-163 163 yuniawati. (2016). peningkatan kualitas pembelajaran ppkn melalui penerapan problem based learning di smp. jurnal pendidikan ips. retrieved from https://journal.uny.ac.id/index.php/hsjpi/article/view/7947/8576. 106 milot lubishtani et al / geosi vol 5 no 1 (2020) 106-126 infrastructural organization of geospatial data in the global level: a case study of albanian global mapping dataset milot lubishtani1, bashkim idrizi2*, subija izeiroski3, fitore bajrami lubishtani2 1 department of geodesy, polytechnic university of tirana, tirana, 1001, albania 2 department of geodesy, university of prishtina “hasan prishtina”, prishtina , 10000, kosovo 3 subsidiary struga, geo-see institute, skopje, 1000, north macedonia *corresponding author : bashkim.idrizi@uni-pr.edu received 12 january 2020/ revised 20 march 2020/ accepted 17 april 2020/ published 24 april 2020 abstract today, the development of economic and financial situation concerning the protection of environment and natural resources in a wider scope depends on the use of geospatial data. one of the main aims of the infrastructural organization of geospatial data is to provide users to be capable of acquiring complete, exact and updated dataset at the right time. this is necessary for providing an ideal environment, where all stakeholders can work collaboratively in an effective way, in order to solve environmental issues and to achieve their targets. global mapping (gm), a project established by united nations, is one of the crucial contributions to the development of global spatial data infrastructure (gsdi). this case study on albanian gm dataset was aimed at performing analyses of infrastructural organization of geospatial data in global-intercontinental level. data standardization of gm as contributor of gsdi was analyzed through developed albanian gm dataset. the main components taken into consideration for performing research analyses were data and metadata, technology, institutional framework, policies, interoperability, network services, search opportunities, and data sharing within gsdi. the main findings of this study are the necessity of infrastructural organization of geospatial data in the global level, known as gsdi, by including official geospatial datasets developed by the national mapping organizations of countries all over the world, in order to be used for environmental monitoring and protection, as well as for early warning management in international level. finally, based on the research results, four conclusions for gsdi are offered, in order to be considered as guideline for further development of unified and globally homogeneous infrastructure of spatial data set. keywords: gsdi; gm; spatial data infrastructure; albania. 1. introduction according to fereira (2005) recent technological advances in geospatial data collection, such as mobile phones, the earth observation and gps (global positioning geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.5 no. 1 (2020), 106-126, april, 2020 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v5i1.16901 accredited by the ministry of research , technology , and higher education of the republic of indonesia, no. 30/e/kpt/2019. mailto:bashkim.idrizi@uni-pr.edu https://jurnal.unej.ac.id/index.php/geosi https://drive.google.com/file/d/1rsnvas6cuhowhl5bj87cl2l6k5dqz7s6/view 107 milot lubishtani et al / geosi vol 5 no 1 (2020) 106-126 system) satellites, have created massive data sets with better spatial and temporal resolution than ever. space agencies worldwide planned to launch around 260 earth observation satellites over the next 15 years. this novel scenario points to the need and spurs on motivation for creating new infrastructures and technologies in order to efficiently store, process, analyze and disseminate large amount of spatiotemporal datasets. according to williamson et al. (2005), cignetti et al. (2019), hoffman-hall (2019), petel (2017), specka (2019), thapa et al. (2019) spatial data, also known as geospatial data or geographic information, are defined as data associated with a specific location on the earth, particularly information regarding natural phenomena, and cultural and human resources. spatial data include maps, aerial and satellite images. many organizations from local, national and regional level produce geospatial data for different purposes. nowadays, we face challenges concerning the production and use of geospatial data. some of them are: (1) in most cases data are collected by differen t organizations and are often incompatible, (2) very often data are with poor quality and poor documentation, (3) organizations that produce spatial data are often restricted to distribute high quality spatial data. the spatial data infrastructure (sdi) concept is generally used to avoid gaps within spatial datasets and duplication in data production in addition to other well -known spatial data problems. according to wu et al. (2018), thompson & de beurs (2018), yang et al. (2018), forkel et al. (2017), lu et al. (2017), chen & wang (2017), vasin & yasakov (2016) creating efficient sdis is an innovative way aiming to design an environment for collaboration and cooperation to solve environmental issues. sdi is mainly a collection of five components which are core spatial data, policies, standards, technologies and institutional arrangement that facilitate the access to geographically-related information (park et al., 2016; lee et al., 2015; choi et al., 2019; yu et al., 2016); sinnott & voorsluys, 2016); foster & mayfield, 2016). an efficient way of accessing geospatial information for public use is by developing geoportals. in fact, a geoportal within the framework of an sdi is a gateway for accessing spatial data, metadata, users and tools that are interactively linked with main aim to use geospatial data in a flexible and efficient way. at the other hand, the geoportals are not just tools but they also facilitate the searching procedures for spatial data. four key concepts underpinning all sdis are: (1) the overriding objective of an sdi is to maximize the use of spatial information. this requires ready access to the geographic information assets held by a wide range of stakeholders in both public and private sector, (2) sdis cannot be realized without coordinated action on the part of governments and agency 108 milot lubishtani et al / geosi vol 5 no 1 (2020) 106-126 partners, (3) sdis must be user driven. their primary purpose is to support decision making for many different purposes, and (4) sdi implementation involves a wide range of activities. these include not only technical matters such as data, technologies, standards, and delivery mechanisms, but also institutional matters related to organizational responsibilities and overall national information policies, as well as questions related to the availability of the financial and human resources needed for this task. concerning the organization of spatial data in the global level, there is an ongoing initiative called global spatial data infrastructure (gsdi). currently gsdi is at an early stage of development, particularly after the establishment of gsdi association in 2002 which includes the development of a proper organizational model, policy and framework, as well as the set up of different working groups for designing and conducting research on the other important components of gsdi. within the framework of this initiative, regional organizations such as eurogi and pcgiap are playing an important role. this initiative was defined by the participants at the second gsdi conference (held at chapel hill, usa, in october 1997) as generally encompassing "the policies, organizational remits, data, technologies, standards, delivery mechanisms, and financial and human resources necessary to ensure that those working at the global and regional scale are not impeded in meeting their objectives". as a result of the growing need for organization and access of geospatial data in many fields, organizations raised the need for development and implementation of spatial data infrastructures (sdi) as well as further researches related to theory and concepts of sdi. hjelmager et al. (2008) state that an sdi is an evolving concept about facilitating and coordinating the exchange and sharing of spatial data between stakeholders from different levels in the spatial data community. one of the core characteristics of well -organized spatial data is the hierarchical structure. these structures can be found nearly everywhere in nature and the man-made environment, e.g. taxonomies, organizations, databases, political systems and government, and parent-child human relationships. the properties of hierarchical systems include simplicity and complexity, upper and lower levels, as well as nested systems within the hierarchical structure. these properties have been adapted in some spatial data applications. in general, it can be said that the higher the level of the sdi, the lower the detail of the data.the hierarchy of sdi systems can be seen in a top down umbrella view (figure 1), or a bottom up building block view (rajabifard et al., 2000; williamson et al., 2005). 109 milot lubishtani et al / geosi vol 5 no 1 (2020) 106-126 figure 1. a)an umbrella view of sdi b) abuilding block view of sdi the national spatial data infrastructure is established in albania by the law and consists in the national geoportal by the state authority for geospatial information (asig). dataset resources for inspire entries are data from albanian geographic (military) institute (agmi), albanian geologic survey (ags), agency for legalization of urban and informal zones and buildings (aluizni), central technical archive in tirana, central office registration of immovable properties and parcels and its branches, national agency of forest, national agency of water, national agency of environment, national agency of territory administration, urban offices in municipalities or cities hall in albania, private companies. in the republic of albania, the organization responsible for developing nsdi is the state authority for geospatial information-asig. asig in collaboration with norway cadastre authority statens kartverk have started initial activity to establish spatial data infrastructure in albania in compliance with the european initiatives and trends. state authority for geospatial information (asig) was established in 2013, according to law 72/2012 "on the organization and functioning of the national infrastructure of geospatial information in the republic of albania" (www.asig.gov.al). the establishment of the ministry of innovation, information technologies (mitik) and communication affirms and reinforces the government's determination for the implementation of national spatial data infrastructure (nsdi). in addition, ,the adoption of the inspire directive, the establishment of an institutional and legal frame for spatial data generation and distribution, and the provision of their use in a national level, are aimed to hinder all misunderstandings and 110 milot lubishtani et al / geosi vol 5 no 1 (2020) 106-126 duplication and improve the quality of the final projects deliverable especially for infrastructure studies and the environment. the idea for developing the global map was launched as a result of unsuccessful completion of the imw (international map of the world in scale 1:1.000.000) and contemporary trends as a result of fast growing information technology in the last decade of the 20th century for preparing the digital maps. based on this idea, the global map has to replace the imw with a new map in digital form according to the accepted homogeneous standards for entire globe. if we consider the structure of the global map,especially regarding the standards listed in its specifications, since its beginning till today,we can see that the global map is not designed as a standard map, but it merely represents the gis database format with specifically defined standards. the lack of cartographic key (cartographic symbols), the lack of cartographic/graphic representation, and the absence of define d map projection are the main arguments which prove that global map is notactually a map but it is a gis database, i.e. global map itself does not contain the basic elements that characterize a map (idrizi et al., 2011). global map is a digital geographic dataset covering the global land areain the scale of 1:1,000,000 and spatial resolution of about 1km. it is, easily accessible with marginal costs, currently freely downloadable for non-profit purposes. this research case study on albanian global map data set combines both, the theoretical and practical issues, conducted, by interaction of theoretical components within practical processes for developing gm dataset for one country and analyzing the necessity for infrastructural organization of geospatial data in the global level based on national level data, known as global spatial data infrastructure (gsdi). this research offers the answer to the main question on the importance of gsdi for international cooperation from national up to global level, on issues related to the environment and official early warning global spatial datasets. the study was performed by using the process of developing the albanian global map dataset, as a case study, in which all research analyzes were conducted. 2. methods derived from a literature research, according to crompvoets (2006) the following sdi-components are to be considered as the main bricks of spatial data infrastructures, i.e.: (1) data sources (organizations generating spatial data); (2) users of spatial data (huma n resources), (3) agreed set of rules, standards (technological and data definition), protocols,procedures, instructions, guidelines); (4) policies (legislation (copyright), accessibility, finance) ; (5) institutional framework (arrangements) affecting databases, meta 111 milot lubishtani et al / geosi vol 5 no 1 (2020) 106-126 data policy,standards; (6) (networked) spatial-datasets (fundamental datasets geodetic) positioning system, digital topographic frameworks, property register, administrative boundaries, elevation model), thematic datasets (soils, hydrology, land use), historical data, and metadata); (7) clearinghouse; (8) legal and technical provision for universal connectivity among databases, directory information and legal rights to interconnect; meta databases and directories describing the content and components of databases; (9) the technologies facilitating the use and transfer of spatial data (networks, electronic data interchange, open gis, data handling facilities, data transfer media). according to idrizi (2018), the basic elements of an sdi are as follows: (1) institutional framework, including legislation, organization, policies and practices; (2) rules for financing and pricing and for handling of security, vulnerability and integrity; (3) standards, including methods for describing spatial data, searching spatial data, ordering and transferring spatial data; (4) fundamental spatial data sets, including geodetic frame, official digital map data, data on real properties, population, buildings and more; and (5) technological framework including human and technical resources, meta data and catalogue services, information network, data distribution, services which makes it easy for users to search, order and collect spatial data. within a national framework of sdi, various datasets (sometimes also indicated by authentic datasets after they have gained a legal status) may be included, such as: (1) co ordinate reference systems; (2) object catalogue including object definitions; (3) geographic name gazetteers; (4) cadastral data; (5) large scale topographic data; (6) elevation data; (7) administrative subdivisions; (8) transportation networks. on the other side, a global framework of sdi may contain a combination of national core datasets or regional datasets. these spatial datasets should be determined a common reference system, object catalogue gazetteers for different types of data in order to be allowed combined use of the different datasets for different purposes. data harmonization is an act of reconciling the definition and representation formats of data elements in a domain of interest. it entails a set of activities that improves the consistency in the use of data elements in terms of their meaning and representation format. in the process of data harmonization, a set of core data elements (data elements expressed using different vocabularies but with identical meaning) can be extracted. one of the main goals of data harmonization is to eliminate redundancies and duplication of datasets in the submission of international trade data. 112 milot lubishtani et al / geosi vol 5 no 1 (2020) 106-126 there are two general approaches for harmonizing data: input harmonization and output harmonization (peter & emily, 2016): (1) input harmonization aims to achieve standardized measurement processes and methods in all national or regional populations. comparability can be realized through standardization of definitions, indicators, classifications, training, and technical requirements, (2) output harmonization begins with different national or regional measurements, possibly derived from non -standardized measurement processes. interoperability is defined as the ability of information and communication technology (ict) systems and of the business processes they support to exchange data and to enable the sharing of information and knowledge (european commission, 2004). the state authority for geospatial information (asig) of albania, following a successful cooperation, signed on 26th of april 2018, the institutional cooperation agreement with statens kartverk for the implementation of the project was financed by the government of norway for the western balkan countries with the object: "capacity building of the state authority for geospatial information on providing geographic information to users". the objectives of this agreement are: (1) enhancing the capacity of the state authority for geospatial information to provide geographic information to users, (2) developing the plan and the first version of the integrated information system for coastal areas with testing in an are, (3) developing the curricula in mapping and cadaster in university system. the establishment of the national geoportal is in its initial phase of structuring and, performing a harmonization of geospatial data in order for users to find it as complete, accurate and up to date. for the users concerned about these geospatial information (citizens, scholars, etc..), asig suggests that the data obtained from the geoportal, firstly have to be verified and confirmed in the relevant institutions, in order that they may gainthe most accurate final information. the vector data of global map v1/v2 (national and regional version) can be downloaded in vpf (vector product format), shape and gml (geography markup language) formats. vpf is a standard format, structure, and organization for large geographic databases that are based on a geo-relational data model, combinatorial topology and set theory, and are intended for direct use (idrizi, 2017). because the use of vpf files is so limited by the existing gis software’s, on october 10th 2008 the existing gm vector data (national/regional version) has also been published in shape format, which is simpler and more user-friendly format. 113 milot lubishtani et al / geosi vol 5 no 1 (2020) 106-126 on october 25th 2009, the gml (standardized in iso 19136) format has replaced the former vpf as the official distribution format of gm data, which provides a standard format for transferring digital geographic data (idrizi et al., 2011). the global map product will encompass the entire globe, at a scale of 1:1 million. all the data sets will be consistent with this scale and these specifications (global map specifications version 2.2., 2012). on the other side, a global framework of sdi may contain a combination of national core datasets or regional datasets. these spatial datasets should be determined a common reference system, object catalogue gazetteers for different types of data in order to be allowed combined use of the different datasets for different purposes. data harmonization is an act of reconciling the definition and representation formats of data elements in a domain of interest. it entails a set of activities that improves the consistency in the use of data elements in terms of their meaning and representation format. in the process of data harmonization,a set of core data elements (data elements expressed using different vocabularies but with identical meaning)can be extracted.one of the main goals of data harmonization is to eliminate redundancies and duplication of datasets in the submission of international trade data. there are two general approaches for harmonizing data: input harmonization and output harmonization (peter & emily, 2016): (1) input harmonization aims to achieve standardized measurement processes and methods in all national or regional populations. comparability can be realized through standardization of definitions, indicators, classifications, training, and technical requirements, (2) output harmonization begins with different national or regional measurements, possibly derived from non-standardized measurement processes. interoperability is defined as the ability of information and communication technology (ict) systems and of the business processes they support to exchange data and to enable the sharing of information and knowledge (european commission, 2004). the state authority for geospatial information (asig) of albania, following a successful cooperation, signed on 26 th of april 2018, the institutional cooperation agreement with statens kartverk for the implementation of the project was financed by the government of norway for the western balkan countries with the object: "capacity building of the state authority for geospatial information on providing geographic information to users". the objectives of this agreement are: (1) enhancing the capacity of the state authority for geospatial information to provide geographic information to users, (2) developing the plan and the first version of the integrated information system for coastal areas with testing in an area, (3) developing the curricula in mapping and cadaster in university system. 114 milot lubishtani et al / geosi vol 5 no 1 (2020) 106-126 the establishment of the national geoportal is in its initial phase of structuring and, performing a harmonization of geospatial data in order for users to find it as complete, accurate and up to date. for the users concerned about these geospatial information (citizens, scholars, etc..), asig suggests that the data obtained from the geoportal, firstly have to be verified and confirmed in the relevant institutions, in order that they may gainthe most accurate final information. the vector data of global map v1/v2 (national and regional version) can be downloaded in vpf (vector product format), shape and gml (geography markup language) formats. vpf is a standard format, structure, and organization for large geographic databases that are based on a geo-relational data model, combinatorial topology and set theory, and are intended for direct use (idrizi, 2017). because the use of vpf files is so limited by the existing gis software’s, on october 10th 2008 the existing gm vector data (national/regional version) has also been published in shape format, which is simpler and more user-friendly format. on october 25th 2009, the gml (standardized in iso19136) format has replaced the former vpf as the official distribution format of gm data, which provides a standard format for transferring digital geographic data (idrizi et al., 2011). the global map product will encompass the entire globe, at a scale of 1:1 million. all the data sets will be consistent with this scale and these specifications (global map specifications version 2.2., 2012). 3. results and discussion the republic of albania has participated in global mapping project since 30th june 2016 in level b, through state authority for geospatial information (asig) as national mapping and spatial data infrastructure organization. republic of albania was the last country participating in gm project, before the dissolution of iscgm and the termination of the global mapping project on august 2016. albanian global map v2, consists both, the vector and raster layers, 8 layers in total, released on 14th of july 2016 in www.iscgm.org, as freely downloadable for non-commercial use (lubishtani & idrizi, 2016). official data wereretrieved from governmental institutions in charge of supplying the current and updated data sets as follows: (1) state authority for geospatial information (asig), (2) institute of transportation, (3) albanian institute of statistics (instat), (4) military geographical institute of albania, (5) ministry of the urban development. in order to harmonize the input data with the gm v2.2 specification, all data received converted, harmonized and generalized, as well reprocessed in cases of satellite 115 milot lubishtani et al / geosi vol 5 no 1 (2020) 106-126 images. the next table and figure,present the list of the developed layers and the directory structure of albanian gm dataset according to gm v2.2 specification for national/regional version. table 1. global map v1/v2 dataset layers national/regional version vector layers raster layers boundaries land cover drainage land use trasportation elevation population centers vegetation figure 2. gm directory structure (global map specifications version 2.2) as an output of the developed albanian gm dataset, eight maps have been compiled, as follows (lubishati & idrizi 2016; lubishtani et al., 2018): 116 milot lubishtani et al / geosi vol 5 no 1 (2020) 106-126 figure 3. figure 4. figure 5. figure 6. transportation layer population centers layer drainage layer boundaries layer figure 7. figure 8. figure 9. figure 10. land cover layer land use layer vegetation layer elevation layer from september 2016, based on the letter of approval from asig, the albanian gm data set were migrated to the united nations geospatial information section (ungis), due to decision for transfer of gm data to ungis database, which has been formalized on august 2016, in new york, during the final (23rd) meeting of iscgm (lubishtani & idrizi, 2016). everything is happening somewhere; hence, most information is related to a place. this is the field, where geographic information system (gis) comes in. a geographic information system has been described in several ways during its development and emergence as a technology. one can define gis as a system of hardware and software, procedures and people designed to capture, to store, to manipulate, to analyze, and to display geo-referenced information (longley et al., 2005). sdi interconnects gis-based servers across the internet. as stated by groot & mc laughlin (2000), an sdi encompasses first the networked geospatial databases and data handling facilities, and then other components. this leads to an argument that gis can be considered the sdi block. although the core sdi concept nests within its scope either base data collection activities or myriad applications built upon it, the infrastructure provides an 117 milot lubishtani et al / geosi vol 5 no 1 (2020) 106-126 ideal environment to connect applications to data influencing both data collection and applications construction through minimal appropriate sta ndards and policies. the role of gis within an sdi is vital. it first creates, manages and serves spatial information, then plays the same role for metadata, and finally provides access to users. briefly we can consider gis an underpinning technology for sdi. the notion that gis is considered a block of an sdi can be seen in figure 11. figure 11. gis as a block of spatial data infrastructure one of the main goals of the development of sdis is to manage and more efficiently use the spatial data assets by considering the needs and information flows from the local level, up through state, national and regional levels and finally to the global (gsdi) level. some of the essential properties of a hierarchical structure relevant for the understanding of hierarchies in general, and spatial hierarchies in particular are as follows: (1) part-whole property: where an element on the higher level consists of one or more elements on the lower level, in view of a part-whole relationship, the higher level is a whole and the lower element is its part, (2) janus-effect: an element at a hierarchical level has two different faces, one looking toward wholes in the higher level and the other looking toward 118 milot lubishtani et al / geosi vol 5 no 1 (2020) 106-126 parts in the lower level. this property was introduced as a fundamental property of all types of hierarchy, (3) near decomposability property: the third fundamental property of hierarchy is called near decomposability. it is related to the nesting of systems within larger sub-systems, and is based on the fact that interactions between various kinds of systems decrease in strength with distance. components that are closer to each other interact more strongly than components that are far apart, many of them are at the same level. figure 12 summarizes the common functional user requirements associated with the relevant steps in the resource life cycle (díaz et al., 2011). moving clockwise, resources must first be published in the sdi, so that they are available for the other stakeholders. then, these resources need to be made searchable and discoverable in the distributed system. figure 12. sdi resource life cycle as stated in idrizi (2017) the main reasons and needs for standardization of spatial data are as follows: (1) standardization lets peers communicate, (2) minimizes cost of uptake of new information, (3) maximizes utility and stability of information products, (4) permits more applications to operate under known conditions. mainly the following standardization organizations are in relation with sdi’s : (1) international organisation of standardization (iso tc 211, tc 204, jtc-1), (2) inspire, (3) world wide web consortium (w3c), opengis consortium (ogc), wsi–i (web services interoperability organization), gsdi (global spatial data infrastructure), national standards organizations. according to 119 milot lubishtani et al / geosi vol 5 no 1 (2020) 106-126 nebert (2009), many standardization activities exist with different roles and responsibilities that are relevant to implementing sdis (figure 13). figure 13. geospatial standardization in sdi (nebert, 2009) as can be seen in figure 13 there are close interactions between sdi as a platform and standardization organizations like: ogc, w3c, iso tc 211 as well as with other nsdi’s. some of the main benefits of data harmonization are: (1) provides a common basis for standardizing data for import, export and logistics information, (2) reduces data redundancy, data duplication and costs of data exchange, (3) ensures data compatibility and enables data interoperability among stakeholders, resulting in further facilitation of trade procedures, (4) provides common semantic standards for import, export and logistics information, (5) provides preparation to develop electronic trade documents, (6) supports the establishment of single window facilities: a single-entry point of standardized information and reuse of information to fulfill all import, export and transit related regulatory requirements. as previously mentioned, the interoperability is the capability to communicate, execute programs, or transfer data among various functional units in a manner that requires the user to have little or no knowledge of the unique characteristics of those units (iso 2382 1, 1993). there are four types of levels that obstruct interoperability of spatial data, i.e.: 120 milot lubishtani et al / geosi vol 5 no 1 (2020) 106-126 cross-border matching of datasets, cross-sector combinations of datasets from different sectors and different content, cross-type of data e.g. combining raster with vector data, and overlap where the same objects coming from different sources contradict both in value and in representation. the global mapping project is an effort in which national mapping organizations (nmos) from more than 180 countries and regions of the world develop global map (gm) through international cooperation (maruyama et al., 2005). the objectives of the global map project are to contribute to solving global environmental problems and achieving sustainable development. in its core meaning, global mapping is a digital geographic dataset of the whole globe which consists of eight thematic layers: boundaries, drainage, population centers, transportation, elevation, land use, land cover and vegetation. these thematic layers of gm dataset should be updated every five years. some of the primary aims of the gm project are: • monitoring and early warning systems for natural disasters; • monitoring and management of natural resources; • assessment of the trends of environmental changes; • local, national and multinational physical development planning; and • informed decision-making of policy makers with a strategic database. according to idrizi (2006), despite the fact thatthe maps are prepared in local/national standards, gm dataset will enable all data of the earth to be: • in one place, • with the same attributes, • in the same format, • in the same coordinate system, • in the same scale, and • with similar accuracy. all structure of data in gm dataset is based on the international iso standards for geographic data, i.e. iso/tc 211the development of global map utilises these following six core iso standards: • iso19136 for the data in gml format, • iso 3166 for nation codes, 121 milot lubishtani et al / geosi vol 5 no 1 (2020) 106-126 • iso 19115 of metadata of gm-v2 by using iso 19139 for encoding, • iso 15046 standard of metadata of v1, • iso 639 for language code, • iso 8601 for date code. some of the main objectives of asig during the process of building nsdi are: • creating geodetic framework to european standards to enable the support of a unique map of the entire territory of the republic of albania. • establishing national infrastructure geospatial data in the republic of albania, through geoportal where everyone can access to geospatial data that possesses albanian state. • designing and developing geo-information standards and their implementation in institutions, whether manufacturer or the geo update. having a global map dataset in digital form on disposal principally allows the modeling of real life situations and also performance of various data manipulation and spatial data analyses. in practical solving issues concerning global map dataset may have limited uses at national and local scales. however, global map dataset is needed to address global, regional, and trans-boundary and in many cases national concerns and environmental issues. therefore, the albanian gm dataset as the latest updated data set will support all types of spatial analyses. by including albanian gm dataset in the global map, direct contribution on regional environmental analyses will be enabled (lubishtani & idrizi, 2016). the concept of knowledge graph may be applied and integrated to sdis to construct knowledge bases that link the geospatial entities and concepts contained in the data. machine learning and data mining methods, such as latent semantic analysis and labeled latent dirichlet allocation may help automatic inference and generation of high quality metadata from the content of maps and services (li et al., 2015). according to hu & li (2017) sdis heavily rely on computer and information technologies, and are continuously evolving with the technological advancements. techniques commonly used in today’s sdis, such as asynchronous javascript and xml (ajax), enable asynchronous processing to speed up search performance as well as user experience. the strategy for building nsdi in albania will lead to relation of nsdi through following strategic areas: (1) cooperation infrastructure, (2) spatial data and services, (3) standardization, (4) legal framework, (5) geodetic reference system, (6) financing and pricing, (7) research, development and 122 milot lubishtani et al / geosi vol 5 no 1 (2020) 106-126 education. in this way the generation of an important infrastructure is delivered in the national level such as albpos, orthophoto for albania, increasing the level of spatial data within a global gis. in this context the mitik focuses on the implementation of the inspire directive which is considered not only a precondition for the integration of albania in eu, but also the main base to establish the national policies on eu. the following are some of the potential applications of global map datasets, i.e. developed albanian global map dataset: • monitoring and early warning systems for natural disasters; • monitoring and management of natural resources; • assessment of the trends of global environmental changes; • local, national and multinational physical development planning; • informed decision-making of policy makers with a strategic database; • global/regional/national perspective and contextual information; • developing ecosystem, drainage basins framework for environmental assessment; • quantifying trans boundary issues; • rapid response capability; • environmental priority setting, analytical studies over large areas. 4. conclusion on the basis of the previous text we can see that there are some important similarities between global map and gsdi. the similarities are the global scope of gm and gsdi, their focus on geospatial data and ability to facilitate geospatial analysis and collaboration. this collaboration in some way is slightly different, because it emphasizes o n a specific physical data product rather than spatial infrastructure development. the sdi development can be considered an important synergistic activity with global map project. therefore, the international collaboration provides a number of relevant lessons and experiences for gsdi collaboration. it is also important to note that the global map project has only been in operation for about five years. therefore, the organization may not have much operational history, but it can still offer some insights for gsdi. first of all, gsdi should focus on specific projects because such projects can help engage participants and educate them about 123 milot lubishtani et al / geosi vol 5 no 1 (2020) 106-126 the importance of sdi activities, such as the importance of metadata and collaboration between participants. with focus and participation in the development of specific spatial data product within global map activities, many countries can be assisted to recognize the importance of gsdi activities and usage. second, the gsdi should develop partnerships and define relationships with other relevant regional and international activities. with defined and developed partnerships with these organizations, gsdi may have access to leveraged resources, increased visibility, and membership. as an example, the provision of an official invitation letter by un to nmo’s to participate in global map project may strengthenth a credibility of the activity and was instrumental in motivating countries' participation. such partnerships can provide synergy and benefits for all the partners. for example, the partnership with pcgiap and pcidea helps increase global map data development and also helps these organizations develop their regional collaborations.third, gsdi needs to develop special activities in order to help developing countries to participate in the international collaborations since they often do not have the resources to participate in such activities. an important mechanism for such outreach is to facilitate country-to-country technical aid and support, such as the level c and level a membership categories in the global map project. special grants and assistance programs are also helpful in this regard, such as the japan international cooperation agency training classes and the esri grant program. fourth, gsdi should also promote and emphasize the benefits of gsdi participation which is essential to increase the active participation in the organization. global map is currently working to distribute such messages to its members to increase active participation in global map project. conflict of interest the authors declare that there is no conflict of interest with any financial, personal, or other relationships with other people or organizations related to the material discussed in the article. references chen, k., & wang, m. (2017). local whittle likelihood estimators and tests for spatial lattice data. journal of statistical planning and inference, 191, 25-42. doi:10.1016/j.jspi.2017.06.001 choi, w. -., ahn, j. -., & shin, d. -. (2019). study on the development of geo-spatial big data service system based on 7v in korea. ksce journal of civil engineering, 23(1), 388399. doi:10.1007/s12205-018-1764-1 124 milot lubishtani et al / geosi vol 5 no 1 (2020) 106-126 cignetti, m., guenzi, d., ardizzone, f., allasia, p., & giordan, d. (2019). an open -source web platform to share multisource, multisensor geospatial data and measurements of ground deformation in mountain areas. isprs international journal of geoinformation, 9(1) doi:10.3390/ijgi9010004 crompvoets, j. w. h. c. (2006). national spatial data clearinghouses: worl dwide development and impact : wageningen university. díaz, l., & schade, s. (2011). geoss service factory: assisted publication of geospatial content. in advancing geoinformation science for a changing world (pp. 423 -442). springer, berlin, heidelberg. european commission, (2004) european interoperability framework for pan-european egovernment services (vers. 1), european communities. ferreira, k. r., de queiroz, g. r., vinhas, l., câmara, g., maurano, l. e., souza, r. c. m., & sanchez, a. (2015). towards a spatial data infrastructure for big spatiotemporal data sets. in 17th brazilian symposium on remote sensing (sbsr), 2015. proceedings (pp. 7588-7594). forkel, m., dorigo, w., lasslop, g., teubner, i., chuvieco, e., & thonicke, k. (2017). a data-driven approach to identify controls on global fire activity from satellite and climate observations (sofia v1). geoscientific model development, 10(12), 44434476. doi:10.5194/gmd-10-4443-2017 foster, d., & mayfield, c. (2016). geospatial resource integration in support of homeland defense and security. international journal of applied geospatial research, 7(4), 5363. doi:10.4018/ijagr.2016100105 groot, r., & mclaughlin, j. (2000). geospatial data infrastructure: concepts, cases and good practice. oxford university press. hjelmager, j., moellering, h., cooper, a., delgado, t., rajabifard, a., rapant, p., ... & iwaniak, a. (2008). an initial formal model for spatial data infrastructures. international journal of geographical information science, 22(11-12), 1295-1309. hoffman-hall, a., loboda, t. v., hall, j. v., carroll, m. l., & chen, d. (2019). mapping remote rural settlements at 30 m spatial resolution using geospatial data-fusion. remote sensing of environment, 233 doi:10.1016/j.rse.2019.111386 holland, p., (2003). global, regional and national sdi initiatives and the global disaster information network (gdin). australian surveying and land information group. hu, y. & li, w. (2017). "spatial data infrastructures", the geographic information science & technology body of knowledge, john p. wilson (ed.). idrizi b. (2017). presentation: sdi from local up to global level, struga : macedonia. idrizi, b. (2006). developing of globally homogeneous geographic data set through global mapping project. kartografija i geoinformacije (cartography and geoinformation), 5(6), 90-101. idrizi, b. (2018). general conditions of spatial data infrastructure. international journal on natural and engineering sciences, 12 (1): 57-62 125 milot lubishtani et al / geosi vol 5 no 1 (2020) 106-126 idrizi, b., meha, m., nikolli, p., & kabashi, i. (2011). data quality of global map and some possibilities/limitations for its wide utilisation for global issues. survey review, 44(325), 134-140. lee, m. h., park, j. m., shin, d. b., & ahn, j. w. (2015). a study on the selection of core services for geo-spatial big data. journal of the korean society of surveying, geodesy, photogrammetry and cartography, 33(5), 385-396. doi:10.7848/ksgpc.2015.33.5.385 li, w., bhatia, v., & cao, k. (2015). intelligent polar cyberinfrastructure: enabling semantic search in geospatial metadata catalogue to support polar data discovery. earth science informatics, 8(1), 111-123. longley, p. a., goodchild, m. f., maguire, d. j., & rhind, d. w. (2005). geographic information systems and science. john wiley & sons. lu, q., ma, y., & xia, g. -. (2017). active learning for training sample selection in remote sensing image classification using spatial information. remote sensing letters, 8(12), 1210-1219. doi:10.1080/2150704x.2017.1375610 lubishtani m., idrizi b. (2016). developing of the albanian global map dataset. micro macro mezzo geo information, 7. lubishtani m., idrizi b., bajrami lubishtani f. (2018). the historical development of global mapping. proceedings, 1st western balkan conference on gis, mine surveying, geodesy and geomatics. tirana. albania. isbn: 978-9928-07-599-4. maruyama h., sasaki h., and takaki o., (2005). global mapping project by national mapping organizations on the globe. in gsdi-9 conference proceedings. nebert, d. (2009). “introduction to geospatial web services.” workshop presentation at global geospatial conference (gsdi11) park, j. m., yu, s. c., ahn, j. w., & shin, d. b. (2016). a study on policy and system improvement plan of geo-spatial big data services in korea. journal of the korean society of surveying, geodesy, photogrammetry and cartography, 34(6), 579-589. doi:10.7848/ksgpc.2016.34.6.579 patel, n. n., stevens, f. r., huang, z., gaughan, a. e., elyazar, i., & tatem, a. j. (2017). improving large area population mapping using geotweet densities. transactions in gis, 21(2), 317-331. doi:10.1111/tgis.12214 rajabifard a., williamson i. p., holland p. & johnstone g., (2000), from local to global sdi initiatives: a pyramid building blocks. proceedings of the 4th gsdi conference (13 – 15 march), cape town, south africa. sinnott, r. o., & voorsluys, w. (2016). a scalable cloud-based system for data-intensive spatial analysis. international journal on software tools for technology transfer, 18(6), 587-605. doi:10.1007/s10009-015-0398-6 specka, x., gärtner, p., hoffmann, c., svoboda, n., stecker, m., einspanier, u., . . . heinrich, u. (2019). the bonares metadata schema for geospatial soil -agricultural research data – merging inspire and datacite metadata schemes. computers and geosciences, 132, 33-41. doi:10.1016/j.cageo.2019.07.005 126 milot lubishtani et al / geosi vol 5 no 1 (2020) 106-126 thapa, r. b., matin, m. a., & bajracharya, b. (2019). capacity building approach and application: utilization of earth observation data and geospatial information technology in the hindu kush himalaya. frontiers in environmental science, 7 doi:10.3389/fenvs.2019.00165 thompson, e. s., & de beurs, k. m. (2018). tracking the removal of buildings in rust belt cities with open-source geospatial data. international journal of applied earth observation and geoinformation, 73, 471-481. doi:10.1016/j.jag.2018.07.007 vasin, y. g., & yasakov, y. v. (2016). distributed database management system for integrated processing of spatial data in a gis. computer optics, 40(6), 919-928. doi:10.18287/2412-6179-2016-40-6-919-928 williamson, i.p., grant, d. and rajabifard, a. (2005). ‘land administration and spatial data infrastructure’. proceedings of fig working week/ gsdi-8, cairo. wu, x., hong, d., ghamisi, p., li, w., & tao, r. (2018). msri -ccf: multi-scale and rotation-insensitive convolutional channel features for geospatial object detection. remote sensing, 10(12) doi:10.3390/rs10121990 yang, l., jin, s., danielson, p., homer, c., gass, l., bender, s. m., . . . xian, g. (2018). a new generation of the united states national land cover database: requirements, research priorities, design, and implementation strategies. isprs journal of photogrammetry and remote sensing, 146, 108-123. doi:10.1016/j.isprsjprs.2018.09.006 yu, s. -., shin, d. -., & ahn, j. -. (2016). a study on concepts and utilization of geo-spatial big data in south korea. ksce journal of civil engineering, 20(7), 2893-2901. doi:10.1007/s12205-016-0504-7 dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 105 spatio-temporal variations of wind speed during harmattan season in northeastern nigeria dantata danlami1, saidu idris1, richard sunday thlakma1 and golly sammy gwandum2 1department of geography faculty of humanities, management and social sciences federal university of kashere, pmb 0182 gombe state, nigeria. 2department of mathematics, college of education p.m.b 011 billiri, gombe state nigeria received 30 january 2019/ revised 4 july 2019/ accepted 15 july 2019/ published 2 august 2019 abstract wind speed is the principal climatic element that drives the marmaton season in west african sub region. it drives the season by conveying huge amount of dust across the northeastern nigeria. the presence of dust in the atmosphere brought by the northeast trade winds during the harmattan season plays a vital role in absorbing and scattering solar radiation. the study examines the spatial and temporal variations of wind speed in northeastern nigeria during the harmattan season with the sole aim of ascertaining its variability, patterns and trends from1984 to 2014. descriptive and statistics such as mean, standard deviation, coefficient of variation, and time series analysis with arcgis 10.3 was used in examine the temporal and spatial variations of wind speed from 1984–2014 in six synoptic stations of northeastern nigeria. the findings show that wind speed varied both temporally and spatially in the last three decades. the pattern of variations in the six synoptic stations shows rising trends within the study years. it was also found that latitude playing a crucial role in determining the speed of the wind in the study area and as the speed of the wind increases with increasing latitude. keywords: wind speed, harmattan, season, northeast, variation and itd. 1. introduction wind speed is the principal driver of the harmattan season in west african sub region. it is the northeast trade wind that seasonally conveys huge amount of dust across the region that produces the harmattan season between november and december of one year and january, february and march of the subsequent year (danlami, 2017). wind speed which is translated as its capacity for rapid motion plays a very remarkable role in influencing the harmattan season variations in northeastern nigeria. it is important to note that, the variation in wind speed distribution is also important with respect to the impacts of climate variability and change (karabulut al.,2012) and (amadiet al.,2014). wind as an element of climate always moves from geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.4 no. 2 (2019), 105-123, august, 2019 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v4i2.11474 dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 106 area of high pressure to area of low pressure system.the movement of the wind in the first place is determined by pressure gradient in the sahara desert during the period of the low sun (winter period in the northern hemisphere) and the greater the pressure of the air, the faster the wind moves. there is no gainsaying that the speed of the wind determines the amount of dust that is seasonally or annually brought into the region. therefore, assessing the speed at which this climatic parameter moves across the study area during harmattan season will go a long way in making sense out of its spatio-temporal variations in last three decades. wind speed is an environmental resource that facilitate the generation of wind energy. due to recent development in wind energy mostly in developed countries (especially in europe) with desire to reduce environmental impacts of the conventional energy resources, there is a general growing interest in the wind energy development in nigeria (adaramola and oyewola 2011). it is against this background this research examines the spatio-temporal variations of wind speed during harmattan season in northeastern nigeria by assessing its variability, patterns and trends from 1984 to 2014.the northeast trade wind controls the harmattan season in west african sub region; it drives the season by conveying huge amount of dust across the region (danlami, 2017). this wind advances into the savannah belts of nigeria due to the seasonal migrations of the inter-tropical discontinuity (itd). the itd attains its southernmost position around latitude 60.001n in january. this marks the peak of the dry season in west africa with all the areas with the exception of the coastal areas under the influence of the dry northeasterly from the sahara desert (ayoade, 2004). the north east trade wind commonly referred to as the harmattan wind; arise due to synoptic-scale of pressure gradients that align north–south across the saharan desert. high pressure to the north of the bodele intensifies the ne trade winds, leading to an increased entrainment of dust in the bodele depression. in summer, dust mobilization cannot be explained by the large scale meteorological conditions. this highlights the importance of local to regional wind systems linked to the northernmost position of the inter-tropical convergence zone (itcz) during this time (schwanghart and schutt, 2007).harmattan season is highly dependent on air pressure variability in the mediterranean area (schwanghart and schutt, 2007). when the northeast trade wind covers substantial parts of west african countries towards the coast and that is when the dry season is experienced. during the months of november and december to the months of january, february and march, the climate of the west african region is dominated by dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 107 northeasterly trade winds. the subtropical pressure belt system over north africa near latitude 300 north is responsible for the movement of the ne trade wind. the deflecting force of the earth’s rotation known as the corilis force is responsible for the northeast direction of this trade wind. winds are caused by pressure differences that induce airflow from zones of high pressure to zones of low pressure (getis el at., 2011). in other words, wind originates from region of high pressure belt and move to the region of low pressure belt. this trade wind that originates from the subtropical high pressure belt in the northern hemisphere plays a key role in influencing the climate of west africa. it is this wind that blows and pick up fine dust and sand particles otherwise known as crustal materials from the sahara desert and produce the harmattan season across west african sub region. 2. the methods the study area in this article is northeastern nigeria. it comprises adamawa, bauchi, borno, gombe and yobe states. it is approximately located between latitudes 90301n and 140.001n and longitudes 90141e and 150.001n. it shares border with niger republic to the north, lake chad to the north-east, and cameroon republic to the east. plateau and taraba states to the south and jigawa state to the west. the locations of the synoptic stations can be seen in table 1. table 1. locations of the six synoptic stations in the study area s/no synoptic stations latitude (0n) longitude (0e) elevation (m) 1 bauchi 100 28ꞌ 090 50ꞌ 616m 2 gombe 100 27ꞌ 110 10ꞌ 449m 3 maiduguri 110 27ꞌ 130 09ꞌ 300m 4 nguru 120 88ꞌ 100 29ꞌ 321m 5 potiskum 110 70ꞌ 110 04ꞌ 475m 6 yola 090 23ꞌ 120 27ꞌ 163m source: danlami (2017) the table above represents the six synoptic stations spread across northeastern nigeria where climatic data are generated by the nigerian meteorological agency (nimet). the data shows the locations and elevations of the synoptic stations in the five states of northeastern dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 108 nigeria. the bauchi station in bauchi state, gombe station in gombe state, maiduguri station in borno state, nguru and potiskum stations in yobe state, and yola station in adamawa state. from the table, it is glaring that bauchi station has the highest elevation in the western part of the study area and yola station with the lowest elevation in the southern part of the study area figure 1. study area source: danlami, (2017) the meteorological data used for the trend-surface analysis in this study was obtained from the nigerian meteorological agency (nimet). the quantitative data covered a period of 30 years (1984 – 2014). in an attempt to analyze the temporal variations and trends of wind speed in the six synoptic stations (bauchi, gombe, maiduguri, nguru, potiskum and yola) in the study area, mean monthly and mean seasonal data were plotted for each station so as to depict the variations and trends in the last three decades. 3. results and discussion the raw wind speed data was subjected to the statistical tools of mean, standard deviation, coefficient of variation; time series through the use of the statistical package for the dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 108 nigeria. the bauchi station in bauchi state, gombe station in gombe state, maiduguri station in borno state, nguru and potiskum stations in yobe state, and yola station in adamawa state. from the table, it is glaring that bauchi station has the highest elevation in the western part of the study area and yola station with the lowest elevation in the southern part of the study area figure 1. study area source: danlami, (2017) the meteorological data used for the trend-surface analysis in this study was obtained from the nigerian meteorological agency (nimet). the quantitative data covered a period of 30 years (1984 – 2014). in an attempt to analyze the temporal variations and trends of wind speed in the six synoptic stations (bauchi, gombe, maiduguri, nguru, potiskum and yola) in the study area, mean monthly and mean seasonal data were plotted for each station so as to depict the variations and trends in the last three decades. 3. results and discussion the raw wind speed data was subjected to the statistical tools of mean, standard deviation, coefficient of variation; time series through the use of the statistical package for the dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 108 nigeria. the bauchi station in bauchi state, gombe station in gombe state, maiduguri station in borno state, nguru and potiskum stations in yobe state, and yola station in adamawa state. from the table, it is glaring that bauchi station has the highest elevation in the western part of the study area and yola station with the lowest elevation in the southern part of the study area figure 1. study area source: danlami, (2017) the meteorological data used for the trend-surface analysis in this study was obtained from the nigerian meteorological agency (nimet). the quantitative data covered a period of 30 years (1984 – 2014). in an attempt to analyze the temporal variations and trends of wind speed in the six synoptic stations (bauchi, gombe, maiduguri, nguru, potiskum and yola) in the study area, mean monthly and mean seasonal data were plotted for each station so as to depict the variations and trends in the last three decades. 3. results and discussion the raw wind speed data was subjected to the statistical tools of mean, standard deviation, coefficient of variation; time series through the use of the statistical package for the dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 109 social sciences (spss) to show the variations and trends of wind speedin the last three decades. also, the study mapped out the spatial patterns over the six different synoptic stations to observe the spatial patterns over time in the arcgis 10.3 environment. the trend equations were also superimposed on the seasonal mean variations of each synoptic station so as to establish their trends over the years in the study area.the trends and variations of wind speed in all the six synoptic stations of the study area were determined by their monthly and seasonal means in the last three decades. the figures 1.2 to 1.8 show clearly the variations in wind speed in all synoptic stations of the study area. it is also glaring from the figures (1.3 to 1.8) that the speed of wind diminishes as it travels southward across the study area. danlami et al (2018) pointed out that the biu plateau is the most important geomorphologic formation in the study area and the strategic location of the biu plateau on the path of the harmattan wind is responsible for the reduction in the speed of the wind thus reducing the amount of dust reaching the extreme south of the study area resulting to moderate visibility in areas around yolastation.they opined that the plateau is a structural and topographical divide between the upper benue basin to the south and the chad basin to the north. 3.1 monthly distribution of wind speed the speed of the northeast trade wind that brings the harmattan dust from the sahara desert and engulfs the whole of west african sub region varies with time and across space. there are slight variations in the speed of wind during the five (5) months of the harmattan season. the speed of the wind is higher at the source region and decreases as it advances towards the gulf of guinea in the south. the validity of this statement can be seen in the sizes of dust particles that are blown by the wind. larger dust particles are usually dropped along the way and the finer particles are moved further down south (de longueville et al., 2010). this is because at the dust source region, the high velocity of the wind could carry larger dust particles but as the wind grows weak in the course of its journey down south, the larger dust particles are dropped and finer ones are moved further into the gulf of guinea and beyond. the speed of the wind therefore, decreases with increase in distance (space) from its source. the wind speed variations can be clearly seen on (fig. 1.2) across the six synoptic stations of the study area. yola station that is located in lowest latitude has the lowest wind speed with long-term monthly mean between 1.00 to 2.00 knots. maiduguri and potiskum stations with the highest mean monthly dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 110 wind speed between 5.00 to 6.00 knots. gombe, bauchi and nguru fall between 3.00 to 5.00 knots during the harmattan season. the mean monthly wind speeds for the whole stations fluctuate between 2.00 to 7.00 knots throughout the harmattan seasons (november, december, january, february and march) in the study area. wind speed is measured in knot in which one knot of wind speed is equal to one nautical mile or one thousand eight hundred and fifty-two meters (1852m) per hour. the international organization of standardization (iso) standard symbol for knot is kn. figure 2. long-term means monthly distribution of wind speed (1984 to 2014) 3.2 seasonal mean distribution of wind speed the northeast trade wind is the driver of the harmattan season across west africa. it drives the season by conveying huge amount of dust into the atmosphere across west african sub region and beyond. the northeast trade wind that advances into the savannah belts of nigeria due to the sudden migration of the inter-tropical discontinuity (itd) southwards in between october and november remains the dominant wind system during the harmattan season in the study area. it is interesting to note that the subtropical high pressure system is usually strong during the harmattan season and it intensifies the movement of the wind which inevitably accounts for rising of the dust over the source regions (bodele depression) in the sahara desert for onward movement across west africa and beyond. the speed of the wind therefore, determines the amount of dust it carries into the atmosphere. 0,00 1,00 2,00 3,00 4,00 5,00 6,00 7,00 8,00 jan feb mar apr may jun jul aug sept oct nov dec w in d s pe ed (k n o ts ) months windspeed bauchi mean gombe mean maiduguri mean nguru mean potiskum mean yola mean dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 111 table 2 shows the influence of latitude and some other local geographical factors that affect the seasonal means distribution of wind speed and coefficient of variations. table 2. descriptive statistics of seasonal wind speed and coefficient of variation s/no stations latitude(y) (0n) mean seasonal wind speed (knots) standard deviation cv (%) 1 bauchi 10.28 3.07 1.72 56.08 2 maiduguri 11.85 5.67 0.69 12.24 3 gombe 10.27 4.21 2.16 51.21 4 nguru 12.88 4.56 0.43 9.40 5 potiskum 11.70 7.08 2.11 29.86 6 yola 9.23 1.68 0.22 12.84 source: danlami (2017) generally, wind speed is relatively low during the harmattan season. it is in the range of 5kn to 20kn in northern nigeria and 5kn to 15kn in southern nigeria (nimet, 2014). the study has found out that wind speed ranges from 1kn to 12kn across the six synoptic stations (fig. 1.3 to 1.8) of the study area. the seasonal means distribution of wind speed in bauchi recorded its lowest in 2003/2004 and the highest in two seasons (2009/2010 and 2010/2011). gombe recorded its lowest wind speed in 1994/1995 and the highest in 2003/2004; maiduguri recorded the lowest wind speed in 1998/1999 and the highest in 2010/2011; nguru recorded the lowest wind speed in 1986/1987 and the highest in 1992/1993; potiskum recorded the lowest wind speed in 1984/1985 and the highest in 1993/1994 and yola recorded the lowest wind speed in 1995/1996 and the highest in 2005/2006. the seasonal means distribution of wind speed in all the synoptic stations in the study area have shown the fluctuating characteristics of the wind speed in all the synoptic stations. the oscillations of the distributions depict most of stationsdominated by the below dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 112 means which are clear indications that the study area is experiencing gradual reduction in the speed of the wind. although all the synoptic stations have shown rising trends; in recent times the distributions in all stations have shown declining patterns and this may not be unconnected with the environmental education and awareness through tree planting campaign as shelter belts to serve as wind breakers by countries within the sudano-sahelian ecological zones. the united nations conference on desertification that came up with “plan of action to combat desertification” has demonstrated great deal of support in promoting and coordinating the plan of action to combat desertification in north africa. figure 3. seasonal mean distributions and trend of wind speed for bauchi station (1984 to 2014) the seasonal mean distribution above shows the trend of wind speed for bauchi station from 1984 – 2014. the mean monthly wind speed is between 1.36kn recorded in 2003/2004 harmattan season and 5.56kn recorded in 2010/2011 and in 2011/2012 harmattan seasons. this fig. 1.3 shows pattern of oscillation around the linear mean where the above average wind speed coincides with the below average. it portrays the inter-annual variation of wind speed in the last thirty (30) years. y = 0,126x + 1,103 r² = 0,371 0,00 1,00 2,00 3,00 4,00 5,00 6,00 7,00 19 84 /1 98 5 19 85 /1 98 6 19 86 /1 98 7 19 87 /1 98 8 19 88 /1 98 9 19 89 /1 99 0 19 90 /1 99 1 19 91 /1 99 2 19 92 /1 99 3 19 93 /1 99 4 19 94 /1 99 5 19 95 /1 99 6 19 96 /1 99 7 19 97 /1 99 8 19 98 /1 99 9 19 99 /2 00 0 20 00 /2 00 1 20 01 /2 00 2 20 02 /2 00 3 20 03 /2 00 4 20 04 /2 00 5 20 05 /2 00 6 20 06 /2 00 7 20 07 /2 00 8 20 08 /2 00 9 20 09 /2 01 0 20 10 /2 01 1 20 11 /2 01 2 20 12 /2 01 3 20 13 /2 01 4 w in d sp ee d (k no tt s) years mean mean 5 per. mov. avg. (mean) linear (mean) dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 113 figure 4. seasonal mean distributions and trend of wind speed for gombe station (1984-2014) the seasonal mean distribution shows the trend of wind speed for gombe station from 1984 – 2014.the mean monthly wind speed is between 1.62kn recorded in 1993/1994 season and 8.34kn recorded in 2003/2004 harmattan season. it shows the pattern of movement around the mean where the above average wind speed coincides with the below average. it portrays the inter – seasonal variation within the period under review. figure 5. seasonal mean distributions and trend of wind speed for maiduguri station (19842014) y = 0,190x + 1,265 r² = 0,523 0,00 2,00 4,00 6,00 8,00 10,00 19 84 /1 98 5 19 85 /1 98 6 19 86 /1 98 7 19 87 /1 98 8 19 88 /1 98 9 19 89 /1 99 0 19 90 /1 99 1 19 91 /1 99 2 19 92 /1 99 3 19 93 /1 99 4 19 94 /1 99 5 19 95 /1 99 6 19 96 /1 99 7 19 97 /1 99 8 19 98 /1 99 9 19 99 /2 00 0 20 00 /2 00 1 20 01 /2 00 2 20 02 /2 00 3 20 03 /2 00 4 20 04 /2 00 5 20 05 /2 00 6 20 06 /2 00 7 20 07 /2 00 8 20 08 /2 00 9 20 09 /2 01 0 20 10 /2 01 1 20 11 /2 01 2 20 12 /2 01 3 20 13 /2 01 4w in d sp ee d (k no tt s) years mean mean 5 per. mov. avg. (mean) linear (mean) y = 0,013x + 5,460 r² = 0,014 2,00 3,00 4,00 5,00 6,00 7,00 8,00 19 84 /1 98 5 19 85 /1 98 6 19 86 /1 98 7 19 87 /1 98 8 19 88 /1 98 9 19 89 /1 99 0 19 90 /1 99 1 19 91 /1 99 2 19 92 /1 99 3 19 93 /1 99 4 19 94 /1 99 5 19 95 /1 99 6 19 96 /1 99 7 19 97 /1 99 8 19 98 /1 99 9 19 99 /2 00 0 20 00 /2 00 1 20 01 /2 00 2 20 02 /2 00 3 20 03 /2 00 4 20 04 /2 00 5 20 05 /2 00 6 20 06 /2 00 7 20 07 /2 00 8 20 08 /2 00 9 20 09 /2 01 0 20 10 /2 01 1 20 11 /2 01 2 20 12 /2 01 3 20 13 /2 01 4 w in d sp ee d (k no tt s) years mean mean 5 per. mov. avg. (mean) linear (mean) dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 114 the seasonal mean distribution shows the trend of wind speed for maiduguri station from 1984 – 2014. the mean monthly is between 3.36kn recorded in 1998/ 1999 season and 7.58kn in 2010/2011. the fig. 1.5 shows pattern of oscillation around the mean where the above average wind speed coincides with the below average. it shows the inter-seasonal variation within the last thirty (30) years. figure 6. seasonal mean distributions and trend of wind speed for nguru station (1984 to 2014) the seasonal mean distribution shows the trend of wind speed for nguru station from 1984 – 2014. the mean monthly win wind speed is between 3.62kn recorded in 1986/1987 season and 5.66kn in 1992/1993 season. the fig. 1.6 shows the pattern movement of the seasonal mean where the above average coincides with the below average. this shows the inter – annual variation of wind speed within the period under review. y = 0,001x + 4,544 r² = 0,000 3,00 3,50 4,00 4,50 5,00 5,50 6,00 19 84 /1 98 5 19 85 /1 98 6 19 86 /1 98 7 19 87 /1 98 8 19 88 /1 98 9 19 89 /1 99 0 19 90 /1 99 1 19 91 /1 99 2 19 92 /1 99 3 19 93 /1 99 4 19 94 /1 99 5 19 95 /1 99 6 19 96 /1 99 7 19 97 /1 99 8 19 98 /1 99 9 19 99 /2 00 0 20 00 /2 00 1 20 01 /2 00 2 20 02 /2 00 3 20 03 /2 00 4 20 04 /2 00 5 20 05 /2 00 6 20 06 /2 00 7 20 07 /2 00 8 20 08 /2 00 9 20 09 /2 01 0 20 10 /2 01 1 20 11 /2 01 2 20 12 /2 01 3 20 13 /2 01 4 w in d sp ee d (k no tt s) years mean mean 5 per. mov. avg. (mean) linear (mean) dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 115 figure 7. seasonal mean distributions and trend of wind speed for potiskum station (19842014) the seasonal mean distribution shows the trend of wind speed for potiskum from 1984 – 2014. the monthly mean for this station shows between 4.48 kn in 2012/2013 season and 9.42kn in 2002/2003 season. it depicts the pattern of movement where the above average coincides with the below average which portrays the inter – annual variation of wind speed within the period under review. y = -0,007x + 7,196 r² = 0,000 2,00 4,00 6,00 8,00 10,00 12,00 14,00 19 84 /1 98 5 19 85 /1 98 6 19 86 /1 98 7 19 87 /1 98 8 19 88 /1 98 9 19 89 /1 99 0 19 90 /1 99 1 19 91 /1 99 2 19 92 /1 99 3 19 93 /1 99 4 19 94 /1 99 5 19 95 /1 99 6 19 96 /1 99 7 19 97 /1 99 8 19 98 /1 99 9 19 99 /2 00 0 20 00 /2 00 1 20 01 /2 00 2 20 02 /2 00 3 20 03 /2 00 4 20 04 /2 00 05 20 05 /2 00 6 20 06 /2 00 7 20 07 /2 00 8 20 08 /2 00 9 20 09 /2 01 0 20 10 /2 01 1 20 11 /2 01 2 20 01 2/ 20 13 20 13 /2 01 4 w in d sp ee d (k no tt s) years mean mean 5 per. mov. avg. (mean) linear (mean) dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 116 figure 8. seasonal mean distributions and trend of wind speed for yola station (1984-2014). the seasonal mean distribution shows trend of wind speed for yola station from 1984 – 2014. the mean monthly distribution is between 1.00kn in 1995/1996 harmattan season and 2.48kn in 2005/2006 season. the station shows a pattern of oscillation around the mean where the above average coincides with the below average. this fig. 1.8 shows a decreasing speed of the wind because it is located at extreme southern part of the study area. this conforms withthe theory that states that the speed of the harmattan wind decreases southward. it shows the inter – annual variation of the speed of the wind within the last thirty (30) years. 3.3 spatial interpolation of sub periods mean of wind speed the surface visibility degradation experienced in the study area is caused by the arrival of the dust brought by the north east trade wind from the bodele depression at the heart of the sahara desert (danlami et al 2018). the arrival of this dust that usually engulfs the region is the most conspicuous sign of harmattan season and therefore, responsible for the degraded visibility. harmattan season low visibility is mainly due to transported dust from the sahara (balarabe et al., 2015). an attempt was made to look at the spatial interpolation of sub period means of surface visibility distribution in the study area with the sole aim of assessing the patterns of the distribution. kriging method of spatial interpolation was employed in this analysis so as to y = 0,001x + 1,652 r² = 0,001 0,50 1,00 1,50 2,00 2,50 3,00 19 84 /1 98 5 19 85 /1 98 6 19 86 /1 98 7 19 87 /1 98 8 19 88 /1 98 9 19 89 /1 99 0 19 90 /1 99 1 19 91 /1 99 2 19 92 /1 99 3 19 93 /1 99 4 19 94 /1 99 5 19 95 /1 99 6 19 96 /1 99 7 19 97 /1 99 8 19 98 /1 99 9 19 99 /2 00 0 20 00 /2 00 1 20 01 /2 00 2 20 02 /2 00 3 20 03 /2 00 4 20 04 /2 00 5 20 05 /2 00 6 20 06 /2 00 7 20 07 /2 00 8 20 08 /2 00 9 20 09 /2 01 0 20 10 /2 01 1 20 11 /2 01 2 20 12 /2 01 3 20 13 /2 01 4 w in d sp ee d (k no tt s) years mean mean 5 per. mov. avg. (mean) linear (mean) dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 117 determine the spatial variations of visibility in the study area. kriging is a geostatistical technique similar to idw in that it uses a linear combination of weights at known points is used to estimate values at other unknown points (willmott et al., 1985; shuman, 2007). kriging and idw methods have been often used to interpolate temperature and precipitation (su-na et al., 2010). idw measures values closest to the prediction location which will have the greatest influence on the predicted values than those farther away (johnston et al., 2001). the northeast trade wind that seasonally conveys huge amount of dust across the west african sub region that produces the harmattan season between november and december of one year and january, february and march of the subsequent year (danlami, 2017) plays a crucial role in regulating the climatic condition of the region. wind speed which is translated as its capacity for rapid motion, plays a very remarkable role in influencing the harmattan season variations in northeastern nigeria. it is important to note that, the variation in wind speed distribution is also important with respect to the impacts of climate variability and change (karabulut al.,2012; amadiet al.,2014). the movement of the wind in the first place is determined by pressure gradient in the sahara desert during the period of the low sun (winter period in the northern hemisphere). the greater the pressure of the air, the faster the wind moves from the region of high pressure to the region of low pressure system. there is therefore, no gainsaying that the speed of the wind determines the amount of dust that is seasonally or annually brought into the region. therefore, assessing the rate at which this climatic parameter moves across the study area during harmattan season will go a long way in making sense out of the spatial variations of the season in last three decades. the spatial variations and distributions of wind speed in northeastern nigeria can be seen in the six sub periods in (fig. 1.9 to 1.14). the sub period of wind speed distribution for 1984/1985 – 1988/1989 in (fig. 1.9) shows variations between 2.27kn in south to 5.79kn in the north of the study area. maiduguri shows the highest wind speed followed by areas around nguru and potiskum. areas around bauchi, gombe and yola in the south show relatively low wind speed in this sub period. the sub periods of wind speed variations and distributions for 1989/1990 – 1993/1994 and 1994/1995 – 1998/1999 in (fig. 10 and 11) show similar variations and distribution patterns. the variations in (fig. 10) and (fig. 11) cover between 1.98kn – 8.78kn and 1.79kn – 7.40kn respectively. potiskum area in both the sub periods show the highest wind speed followed by dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 118 nguru and maiduguri in the north. areas around bauchi, gombe and yola in both sub periods witnessed relatively low wind speed. the sub period of wind speed variations and distributions for 1990/2000 – 2003/2004 in (fig. 12) shows variation between 1.71 kn in the south and 7.05 kn in the north. areas around potiskum, nguru and gombe witnessed high wind speed while bauchi and yola in the south were low. the sub period of wind speed variations and distributions for 2004/2005 – 2008/2009 in (fig. 1.13) shows variations between 2.71 kn in south and 7.11 kn in the north. potiskum area shows high wind speed followed by nguru, maiduguri and gombe. bauchi and yola areas show low. the sub period for 2009/2010 – 2013/2014 in (fig. 14) shows relatively high wind speed across the study area. it varies between 3.56kn in the south and 6.62 kn in the north. maiduguri areas witnessed high wind speed followed by nguru, potiskum and gombe while bauchi and yola were low. it is important to know that the speed of the wind decreases as it moves southwards due to distance (latitudes) and friction generated by the earth-bound materials carried by the wind in the study area (danlami, 2017). moreover, the undulating plains in the chad basin formation in maiduguri and potiskum are responsible for high speed of the wind experienced in the region. it is important to state here that wind speed tends to be higher in areas where there are no barriers like shelter belts and highlands. figure 9. spatial wind speed distribution in northeastern nigeria (19984/1985 to1988/1989) dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 118 nguru and maiduguri in the north. areas around bauchi, gombe and yola in both sub periods witnessed relatively low wind speed. the sub period of wind speed variations and distributions for 1990/2000 – 2003/2004 in (fig. 12) shows variation between 1.71 kn in the south and 7.05 kn in the north. areas around potiskum, nguru and gombe witnessed high wind speed while bauchi and yola in the south were low. the sub period of wind speed variations and distributions for 2004/2005 – 2008/2009 in (fig. 1.13) shows variations between 2.71 kn in south and 7.11 kn in the north. potiskum area shows high wind speed followed by nguru, maiduguri and gombe. bauchi and yola areas show low. the sub period for 2009/2010 – 2013/2014 in (fig. 14) shows relatively high wind speed across the study area. it varies between 3.56kn in the south and 6.62 kn in the north. maiduguri areas witnessed high wind speed followed by nguru, potiskum and gombe while bauchi and yola were low. it is important to know that the speed of the wind decreases as it moves southwards due to distance (latitudes) and friction generated by the earth-bound materials carried by the wind in the study area (danlami, 2017). moreover, the undulating plains in the chad basin formation in maiduguri and potiskum are responsible for high speed of the wind experienced in the region. it is important to state here that wind speed tends to be higher in areas where there are no barriers like shelter belts and highlands. figure 9. spatial wind speed distribution in northeastern nigeria (19984/1985 to1988/1989) dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 118 nguru and maiduguri in the north. areas around bauchi, gombe and yola in both sub periods witnessed relatively low wind speed. the sub period of wind speed variations and distributions for 1990/2000 – 2003/2004 in (fig. 12) shows variation between 1.71 kn in the south and 7.05 kn in the north. areas around potiskum, nguru and gombe witnessed high wind speed while bauchi and yola in the south were low. the sub period of wind speed variations and distributions for 2004/2005 – 2008/2009 in (fig. 1.13) shows variations between 2.71 kn in south and 7.11 kn in the north. potiskum area shows high wind speed followed by nguru, maiduguri and gombe. bauchi and yola areas show low. the sub period for 2009/2010 – 2013/2014 in (fig. 14) shows relatively high wind speed across the study area. it varies between 3.56kn in the south and 6.62 kn in the north. maiduguri areas witnessed high wind speed followed by nguru, potiskum and gombe while bauchi and yola were low. it is important to know that the speed of the wind decreases as it moves southwards due to distance (latitudes) and friction generated by the earth-bound materials carried by the wind in the study area (danlami, 2017). moreover, the undulating plains in the chad basin formation in maiduguri and potiskum are responsible for high speed of the wind experienced in the region. it is important to state here that wind speed tends to be higher in areas where there are no barriers like shelter belts and highlands. figure 9. spatial wind speed distribution in northeastern nigeria (19984/1985 to1988/1989) dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 119 figure 10. spatial wind speed distribution in northeastern nigeria (1989/1990 to1993/1994) figure 11. spatial wind speed distribution in northeastern nigeria (1994/1995 to 1998/1999) figure 12. spatial wind speed distribution in northeastern nigeria (1999/2000 to2003/2004) dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 119 figure 10. spatial wind speed distribution in northeastern nigeria (1989/1990 to1993/1994) figure 11. spatial wind speed distribution in northeastern nigeria (1994/1995 to 1998/1999) figure 12. spatial wind speed distribution in northeastern nigeria (1999/2000 to2003/2004) dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 119 figure 10. spatial wind speed distribution in northeastern nigeria (1989/1990 to1993/1994) figure 11. spatial wind speed distribution in northeastern nigeria (1994/1995 to 1998/1999) figure 12. spatial wind speed distribution in northeastern nigeria (1999/2000 to2003/2004) dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 120 figure 13. spatial wind speed distribution in northeastern nigeria (2004/2005 to 2008/2009 figure 14. spatial wind speed distribution in northeastern nigeria (2009/2010 to 2013/2014) from the above analysis, it is glaring that wind speed in the study area shows a regular distribution pattern in the last three decades. the speed of the wind increases northwards i.e. relatively low in the south and high in the north. this conforms to the work of (adaramola and oyewole 2011) where they reported that wind speed is low in southern nigeria and relatively high in the northern parts of the country. the relief and other local factors in the study area could account for the variations and the distribution patterns of this climatic parameter across the region. it is important to note that maiduguri and potiskum have featured prominently as areas with high wind speed at one point or the other within the sub periods and this may not be dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 120 figure 13. spatial wind speed distribution in northeastern nigeria (2004/2005 to 2008/2009 figure 14. spatial wind speed distribution in northeastern nigeria (2009/2010 to 2013/2014) from the above analysis, it is glaring that wind speed in the study area shows a regular distribution pattern in the last three decades. the speed of the wind increases northwards i.e. relatively low in the south and high in the north. this conforms to the work of (adaramola and oyewole 2011) where they reported that wind speed is low in southern nigeria and relatively high in the northern parts of the country. the relief and other local factors in the study area could account for the variations and the distribution patterns of this climatic parameter across the region. it is important to note that maiduguri and potiskum have featured prominently as areas with high wind speed at one point or the other within the sub periods and this may not be dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 120 figure 13. spatial wind speed distribution in northeastern nigeria (2004/2005 to 2008/2009 figure 14. spatial wind speed distribution in northeastern nigeria (2009/2010 to 2013/2014) from the above analysis, it is glaring that wind speed in the study area shows a regular distribution pattern in the last three decades. the speed of the wind increases northwards i.e. relatively low in the south and high in the north. this conforms to the work of (adaramola and oyewole 2011) where they reported that wind speed is low in southern nigeria and relatively high in the northern parts of the country. the relief and other local factors in the study area could account for the variations and the distribution patterns of this climatic parameter across the region. it is important to note that maiduguri and potiskum have featured prominently as areas with high wind speed at one point or the other within the sub periods and this may not be dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 121 unconnected with the influence of the easterlies wind in shifting the flow pattern of the northeast trade wind. the spatial analysis of the wind speed in the last couple of decades has shown that it is on the rise which agrees with the temporal analysis. this sends a signal that the desert is vigorously advancing into the savannah belts of nigeria because the northeast trade wind is responsible for the desert-like conditions in the sudano-sahelian ecological zone of the study area. the spatial analysis also agrees with what (dahuwa el at., 2018) where they reported that the wind speeds for azare, bauchi state, are high enough to support wind power generation in all strong wind regions of the country. the speed of the wind during the harmattan season is seen to be stronger in the months of december and january and this conforms to what was reported by (waewsak et al., 2011). they opined that wind speedanalysis showed strong and sufficient wind for power generation occurred during the months of january to july and in the month of october 2008 in thasala district in the southern province of thailand where the south east asian monsoon is experienced which is similar to west african monsoon. fagbenle et al., (1980) reported that average wind speed across nigeria is about 3 m/s. in addition, they found that wind speeds are generally higher in the northern part of nigeria than in the southern part of the country. ojosu and salawu (1990a) studied wind speed data from 1951-1975 from 22 stations across the country and they concluded that sokoto area (in northern part) have highest wind speed of about 5.12 m/s in june and annual average of 3.92 m/s 4 conclusion wind speed is the principal climatic element that drives the harmattan season in west african sub region. it drives the season by conveying huge amount of dust from the sahara desert particularly from the bodele depression across the northeastern nigeria. the speed of the wind varied both temporally and spatially with latitude and some geographical factors playing significant role in bringing about the patterns of variations and their trends over the years i.e. it is higher in the north particularly around maiduguri and potiskum areas due to the plains of the chad basin formation and lower in the south due to some geographical factors such the fika hills in the southern part of potiskum and as well as the strategic location of the biu plateau that separate the chad basin formation to the north and the benue trough to the south. dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 122 acknowledgement we wish to acknowledge the nigerian meteorological agency (nimet) for providing us with the data to carry out this climatic study. references adaramola,m.s.andoyewola,o. m. (2011). wind speed distribution and characteristics in nigeria. asian research publishing network (arpn). journal of engineering and applied sciences.issn 1819-6608.www.arpnjournals.com amadi, s. o., udo, s. o. and ewona, i. o. (2014). trends in monthly mean minimum and maximum temperature data over nigeria for the period 1950-2012. international research journal of pure and applied physics,2(4), 1-27. ayoade, j.o. (2004). introduction to climatology for the tropics.2nd ed. spectrum books limitted, spectrum house ring road ibadan, nigeria. balarabe, m., abdallah, k., and nawawi, m. (2015). longterm trend and seasonal variability of horizontal visibility in nigerian troposphere.journal of atmosphere 6:1462-1486; doi:10.3390/atmos6101462. dahuwa, d., promise, k. u., umar, w., bello, i. and mohammed, r. (2018). analysis of wind speed and frequency inazare north eastern part of nigeria. iosr journal of applied physics (iosr-jap) e-issn: 2278-4861.volume 10, issue 1 ver. i. pp 09-17 www.iosrjournals.org doi: 10.9790/4861-1001010917 www.iosrjournals.org danlami, d., gwari, m., suleiman, s., and bara, a. (2018). temporal and spatial variations of groung surface visibility during harmattan season in north-eastern nigeria.ceylon journal science, 47(4), 337 – 346. doi: http://doi.org/10.4038/cjs.v47i4.7551. danlami, d. (2017). spatio-temporal variations of harmattan season in northeastern nigeria.m.sc. dissertation (not published) submitted to the department of geography, bayero university, kano, nigeria. de longueville, f., hountondji, y. c., henry, s. and ozer, p. (2010). what do we know about the effects of desert dust on air quality and human health in west africa compared to other regions? journal: science of total environment fagbenle, r.l., fasade, a.o., amuludun a.k. andlala,p.o.( 1980). wind power potentials of nigeria. 12th biennial conference of the west african science association, university of ife, nigeria. getis, a., getis, j., bjelland, m. and fellmann, j.d. (2011).introduction to geography. 13thed. the mcgraw-hill companies, inc., 1221 avenue of the americas, ny10020. dantata danlami, et al/ geosi vol. 4 no. 2 (2019) 105-123 123 karabulut, m., demirci, a. and kora, f. (2012). analysis of spatially distributed annual, seasonal and monthly temperatures in istanbul from 1975 to 2006.world applied sciences journal, 12(10), 1662-1675 ojosu, j.o. and salawu, r.i. (1990).an evaluation of wind energy potential as a power generation source in nigeria.solar & wind technology.elsevier.volume 7, issue 6, 1990, pages 663-673 schwanghart, w. and schutt, b. (2007). meteorological causes of harmattan dust in west africa. journal of science direct geomorphology. shuman, m. (2007) evaluation of five gis basedinterpolation techniques for estimating the radonconcentration for unmeasured zip codes in thestate of ohio, master of science degree in civil engineering, university of toledo, 28-29 pp. waewsak, j., chancham, c., landry, m. and gagnon, y (2011).an analysis of wind speed distribution at thasala, nakhon si thammarat, thailand.journal of sustainable energy & environment 2 pp 51-55 willmott, c., robeson, s. and philpot, w. (1985). smallscale climate maps: a sensitivity analysisof some common assumptions associated withgrid-point interpolation and contouring. american cartographer 12(1):5-16. acknowledgement the editorial board would like to thank and express appreciation to all peer reviewers who have reviewed the manuscripts for publication of geosfera indonesia. marinela istrate (scopus id : 56672996500) department of geography, universitatea alexandru ioan cuza, iasi, romania lucian rosu (scopus id : 56958158800) department of geography, universitatea alexandru ioan cuza, iasi, romania mihai niculita (scopus id : 55022909500) department of geography, alexandru ioan cuza university of iasi, romania tin lukic (scopus id : 54795557700) department of geography, university of novi sad, serbia fatih adiguzel (scopus id : 57204062132) , department of geography, nevşehir haci bektaş veli üniversitesi, nevsehir, turkey elan artono nurdin (scopus id : 57192649049) department of geography education, university of jember, indonesia bejo apriyanto (scopus id : 57208468203) department of geography education, university of jember, indonesia prima widayani (scopus id : 57188879871) faculty of geography, gadjah mada university, indonesia ivan taslim (scopus id : 57203022349) department of geography, universitas muhammadiyah gorontalo, indonesia efdal kaya (scopus id : 57202135756) department of architecture and urban planning, iskenderun technical university, iskenderun, turkey batuhan kilic (scopus id : 57204675825) geomatic engineering department, yildiz technical university, istanbul, turkey nailul insani (scopus id : 57208471498) department of geography, universitas negeri malang, indonesia rendra zainal maliki department of geography education, universitas tadulako, indonesia faisal arif setiawan department of geography education, universitas lambung mangkurat, indonesia aulia ulfa farahdiba (scopus id : 57208130620) , department of environmental engineering, universitas pembangunan nasional "veteran" jawa timur, indonesia guruh samodra (scopus id : 55053491600) faculty of geography, universitas gadjah mada, yogyakarta, indonesia andri estining sejati (scopus id : 57211280452) geography education study program, universitas sembilanbelas november, kolaka, indonesia wahid akhsin budi nur sidiq (scopus id : 57201676728), department of geography, universitas negeri semarang, semarang indonesia pertiwi andarani (scopus id : 55959123900), department of environmental engineering, universitas diponegoro, semarang, indonesia prama ardha aryaguna (scopus id : 56236908900), department of survey and mapping, faculty of engineering, universitas esa unggul, jakarta, indonesia ionuț minea (scopus id : 56951000900), faculty of geography and geology, department of geography, alexandru ioan cuza university, 20 a, carol i bd., 700505 iasi, romania rosmadi fauzi (scopus id : 6508044388), department of geography, university of malaya, kuala lumpur, malaysia pramaditya wicaksono (scopus id : 54279699900), faculty of geography, universitas gadjah mada, indonesia mahendra andiek maulana (scopus id : 57189494749), faculty of civil engineering planning and earth science, institut teknologi sepuluh nopember, surabaya, indonesia very dermawan (scopus id : 57190389285), water resources engineering department, universitas brawijaya, malang, indonesia geos geosfera indonesia geosfera indonesia is a journal publishes original research, review, and short communication (written by researchers, academicians, professional, and practitioners from all over the world) which utilizes geographic and environment approaches (human, physical landscape, nature-society and gis) to resolve human-environment interaction problems that have a spatial dimension. moreover, geosfera indonesia also committed to enhance and share original research, review, and short communication (written by researchers, academicians, professional, and practitioners from all over the world) on geography education and environmental education. our journal's scope includes : 1. geography education 2. physical geography 3. human geography 4. geographic information system (gis) 5. remote sensing 6. environmental science 7. environmental education 8. disaster risk reduction indexed by : geos geosfera indonesia geosfera indonesia is a journal publishes original research, review, and short communication (written by researchers, academicians, professional, and practitioners from all over the world) which utilizes geographic and environment approaches (human, physical landscape, nature-society and gis) to resolve human-environment interaction problems that have a spatial dimension. moreover, geosfera indonesia also committed to enhance and share original research, review, and short communication (written by researchers, academicians, professional, and practitioners from all over the world) on geography education and environmental education. our journal's scope includes : 1. geography education 2. physical geography 3. human geography 4. geographic information system (gis) 5. remote sensing 6. environmental science 7. environmental education 8. disaster risk reduction indexed by : geos geosfera indonesia geosfera indonesia is a journal publishes original research, review, and short communication (written by researchers, academicians, professional, and practitioners from all over the world) which utilizes geographic and environment approaches (human, physical landscape, nature-society and gis) to resolve human-environment interaction problems that have a spatial dimension. moreover, geosfera indonesia also committed to enhance and share original research, review, and short communication (written by researchers, academicians, professional, and practitioners from all over the world) on geography education and environmental education. our journal's scope includes : 1. geography education 2. physical geography 3. human geography 4. geographic information system (gis) 5. remote sensing 6. environmental science 7. environmental education 8. disaster risk reduction indexed by : sergio bernardes et al / geosi vol 5 no 3 (2020) 352-363 352 emerging geospatial technologies in environmental research, education, and outreach sergio bernardes, marguerite madden*, ashurst walker, andrew knight, nicholas neel, akshay mendki, dhaval bhanderi, andrew guest, shannon healy, thomas jordan center for geospatial research, department of geography, university of georgia, athens, georgia, ga 30602, united states of america *corresponding author: mmadden@uga.edu received 1 november 2020/ revised 16 december 2020 / accepted 22 december 2020/ published 30 december 2020 abstract drawing on the historical importance of visual interpretation for image understanding and knowledge discovery, emerging technologies in geovisualization are incorporated into research, education and outreach at the center for geospatial research (cgr) in the department of geography at the university of georgia (uga), usa. this study aimed to develop the 3d immersion and geovisualization (3dig) system consisting of uncrewed aerial systems (uas) for data acquisition, augmented and virtual reality headsets and mobile devices, an augmented reality digital sandbox, and a video wall. we were working together integrated data products from the uas imagery, including digital image mosaics and 3d models, and readily available gaming engine software to create augmented and virtual reality immersive visualizations. the use of 3dig in research is demonstrated in a case study documenting the seasonal growth of vegetables in small gardens with a time series of 3d crop models generated from uas imagery and structure from motion photogrammetry. demonstrations of 3dig in geography and geology courses, as well as public events, also indicate the benefits of emerging geospatial technologies for creating active learning environments and fostering participatory community engagement. keywords: environmental education; geovisualization; augmented reality; virtual reality; uas, photogrammetry 1. introduction there is an old saying, “seeing is believing.” regarding remote sensing and image processing for environmental research, education and outreach, the saying should be adapted to read, “seeing is believing and understanding.” long before there were computers available to analyze and classify remotely sensed imagery acquired from aerial or satellite platforms, men and women bent over light tables and examined hardcopy aerial photographs with the aid of a stereoscope and visually interpreted the features they viewed in three dimensions. anson (1968) described that “photographic interpretation originated when the images recorded on sensitized geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.5 no. 3 (2020), 352-363, december, 2020 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v5i3.20719 accredited by the ministry of research , technology , and higher education of the republic of indonesia, no. 30/e/kpt/2019. geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.5 no. 3 (2020), 301-317, december, 2020 https://jurnal.unej.ac.id/index.php/geosi doi : accredited by the ministry of research , technology , and higher education of the republic of indonesia, no. 30/e/kpt/2019. mailto:mmadden@uga.edu https://jurnal.unej.ac.id/index.php/geosi https://drive.google.com/file/d/1rsnvas6cuhowhl5bj87cl2l6k5dqz7s6/view https://jurnal.unej.ac.id/index.php/geosi https://drive.google.com/file/d/1rsnvas6cuhowhl5bj87cl2l6k5dqz7s6/view sergio bernardes et al / geosi vol 5 no 3 (2020) 352-363 353 material by radian energy were first recognized during photographic processing. the recognition process became valid for the individual who recalled or recognized a familiar object, person, or scene which created a response in the mind of the interpreter.” with the advent of computer technology, the conversion of hardcopy to digital imagery and the evolution of analog to digital image processing, researchersexplored the use ofautomated methods of image understanding while maintaining the importance of visual image assessment. the application of computerbased systems by a photo interpreter is to enhance the digitized photographs to facilitate human interpretation. although great strides have been made in applying digital image processing to automatically classify various surface features, these techniques still fall far short of the human interpreter (colwell, 1997). by the 2000s, digital image classification was well-established and great advances were made in refining image classification algorithms, multi-sensor image data fusion and mainstream use of dedicated image processing software (campbell, 2002; lillesand et al., 2003; jensen, 2007; sabins 2007). the need for visual understanding of image features remains and important component of even the most sophisticated computer algorithms. early image classifications methods (e.g., supervised image classification) relied on training sets identified by humans and of consisting o f pixels identified in an image as representative of ground features to be classified (lillesand et al., 2003). the elements of image interpretation, (i.e., tone, shape, size, pattern, association, shadow, texture and resolution) published in a seminal publication by olson (1960), integrated different aspects of image understanding into a single framework that is still used today as the basis of many image processing algorithms including pixel-based classification, object-based image analysis, automated feature extraction, machine learning and deep learning. the subject of human factors in image interpretation, cognition and remote sensing is discussed ascentral to mixed methods research, geospatial intelligence, perceptual processes and the capture of expert knowledge towards the automation of the interpretation process in white et al. (2018). current challenges include the interpretation and integration of multiple data types, especially dynamic data, while taking advantage of emerging technologies in geovisualization (hoffman, 2018). the potential of using multimedia in cartography and visualizing environments using virtual reality was recognized by early geospatial visionaries in the 1990s and early 2000s (taylor, 1994; cartwright, 1994; slocum et al., 2001). cartwright (1994) noted cartographers have always designed and produced maps using numerous media elements and tools including sergio bernardes et al / geosi vol 5 no 3 (2020) 352-363 354 computer graphics, photogrammetry, statistical analyses and geographic information systems (gis). “the ability to integrate picture, sound and movement gives the ability to assemble almost any combination of presentation package required for a particular spatial data presentation, including graphic solutions using space-time data” (cartwright, 1994). discussions on the use of geographic multimedia and hypermedia recognized the integration of new methods of digital data integration, display and interaction with users within gis and early adoption of hypertext for linking internet content within digital cartographic designs (stefanakis et al., 2006).virtual realities were also being promoted as gaming technologies evolved and cartographers recognized the advantages of virtual interfaces to geographic content for research and graphic communication (cartwright, 2006; bainbridge, 2007). the visualization of changing vegetation patterns related to terrain characteristics and disturbances such as wildfires, insect infestation and human impacts also were explored as three-dimensional, time-series geovisualizations and virtual realities (madden et al., 2006 & 2009). this study aimed to developed the 3d immersion and geovisualization (3dig) system consisting of uncrewed aerial systems (uas). 2. methods researchers at the department of geography’s center for geospatial research at the university of georgia have created a 3d immersion and geovisualization (3dig) system aimed to bring multiple technological components for data acquisition, extended reality or xr (i.e., virtual, augmented and mixed reality) and geovisualization for earth science research, education and outreach. the motivation for 3dig began with the recognition that students are increasingly visual learners. they enter universities with experience using 3d immersive video games and expectations regarding the use of modern technologies for learning. recognizing the need for geography-ready immersive technologies that support visual and experiential learning led to the design of the 3dig system. we hypothesized bringing 3d graphics and visualization technologies to traditional lectures and instructional materials would promote student learning and understanding of geographic concepts that are often difficult to grasp. sergio bernardes et al / geosi vol 5 no 3 (2020) 352-363 355 the components of 3dig include uncrewed aerial systems (uas), virtual and augmented reality headsets and mobile devices, an augmented reality sandbox and a video wall (bernardes et al., 2018, figure 1). a dji phantom 4 pro quadcopter and a dji matrice 600 pro hexacopter are used to acquire high spatial and temporal resolution images and videos. the phantom 4 pro uas has features such as attitude control, automatic take-off and landing, collision avoidance and video game-like flight controls that facilitate flying by students and young researchers with no previous exposure to uas. the matrice 600 pro hexacopter allows a heavier payload with multiple sensors such as the micasense 5-band multispectral, velodyne lidar and flir thermal sensors. the cgr personnel with remote pilot certification provide flight training, demonstrations and instruction for students to obtain their own certification required for conducting research and outreach. virtual and augmented reality goggles (e.g., oculus rift, quest and microsoft hololens) are demonstrated in classes and used by students in many courses in the geosciences and other fields to expose students to emerging technologies and provide immersive experiences in virtual and augmented landscapes, international cities and a variety of landforms (bernardes et al., 2020, figure 2). figure 1. the 3d immersion and geovisualization (3dig) system incorporates uncrewed aerial system (uas) data acquisition, virtual and augmented reality and video wall for use in research, education and outreach sergio bernardes et al / geosi vol 5 no 3 (2020) 352-363 356 the augmented reality sandbox was designed and built in-house by uga-cgr students and faculty. the system consists of two xbox kinect sensors configured to interact with the topography of the sand contained within a wooden box supported on a frame at waist height. a downward-pointing projector is connected to a laptop such that the display of geospatial data and model output can be projected onto the surface of the sand. intended to be interactive and participatory, users gather around the sandbox and are encouraged to move the sand with their hands to build “mountains and valleys” that can even recreate the topography of real locations. see petrasova et al. (2015), for a complete discussion of tangible modeling and software/hardware requirements for constructing an augmented reality sandbox. the uga-cgr sandbox was designed to be transportable with casters and a telescopic structure such that the frame can be lowered to fit through doorways and wheeled to classrooms, laboratories, other buildings or even public spaces. in this way, exposure to the augmented reality technology can be maximized and to-date the sandbox and mobile goggles have been used in 55 courses and 13 public events for over 6,000 individual interactions. figure 2. virtual reality headsets allow students access to remote environments, immersive experiences in a variety of landscapes and exposure to cultural resources sergio bernardes et al / geosi vol 5 no 3 (2020) 352-363 357 figure 3. (a) augmented reality sandboxdesigned and built in-house at the university of georgia’s geography department center for geospatial research for (b) participatory tangible experiences and geovisualization of geographic concepts the final component of the 3dig system is a video wall consisting of four nec 46-inch high-performance commercial grade video displays that are daisy chained and controlled by a single windows-based computer using tilematrix technology. visual integration of the four individuals displays is facilitated by reducing the bezel width (i.e., the outside edge of the display) to 1.9 mm (minimum) or 3.8 mm (maximum) per display. the use of serviceable wall mounts and inter-display wall calibration also provides an improved visualization experience. when combined with augmented reality goggles, multiple students in the class are able to see what the person wearing the microsoft hololens goggles is experiencing. although not in threedimensions, the two-dimensional view displayed on the video wall allows students to see the augmented reality that is otherwise invisible to everyone except the person wearing the headset (figure 4). (a) (b) sergio bernardes et al / geosi vol 5 no 3 (2020) 352-363 358 figure 4. the video wall combined with augmented reality goggles allows multiple students in the class to see what the person wearing the microsoft hololens goggles is experiencing 3. results and discussion a case study applying emerging technologies used by 3dig for research, education and outreach was performed, by using ua sand photogrammetry for small farm agricultural monitoring, research and outreach to local communities. acknowledging small farms and community gardens are important in local culture, economies and food supplies, integrated geospatial techniques of uas image acquisition, structure from motion (sfm) photogrammetry, field-based measurements of plants and 3d crop models were developed to assist farmers and community gardeners who may not normally have access to advanced geospatial technologies. a uas was used to fly low-altitude imagery of vegetable gardens throughout the growing season. digital image mosaics and 3d crop models were produced with sfm photogrammetric software (metashape by agisoft) that depict the growth forms of individual plants and can be measured to quantify changes in crop biomass over time (figure 5a). gaming engine software such as unity or unreal engine can then be used to convert 3d models to augmented reality displays to visualize virtual gardens in a classroom or public setting (figure 5b). sergio bernardes et al / geosi vol 5 no 3 (2020) 352-363 359 a) b) figure 5. (a) 3d crop models produced by photogrammetry and uas images of small gardens can be converted to augmented reality displays (b) for public viewing emerging developments in virtual, augmented and mixed reality and increased accessibility to the hardware and software required to access their implementations have led to renewed interest and new possibilities for uses in research, education and outreach. çöltekin et (a) (b) sergio bernardes et al / geosi vol 5 no 3 (2020) 352-363 360 al. (2020) provide a thorough review of research challenges and future directions in xr within the spatial sciences. noted is the need for a consensus of definitions for fundamental terms of extended reality because there is ambiguous use of virtual, augmented and mixed reality (çöltekin et al., 2020). this is especially important when these advanced technologies are being incorporated into educational materials, research manuscripts and outreach demonstrations in order to minimize confusion and harmonize the discussion of advantages and limitations. milgram & kishino (1994) presented a continuum of realities ranging from the real environment to the virtual environment and predicted future experiences will be increasingly mixed virtual and real views of the world around us. as of 2020, it is estimated that over 6,000 students, ranging from pre-kindergarten (i.e., less than five years old) to university levels of education, have been exposed to the 3dig system in 55 courses or course sessions in a variety of disciplines including physical geography, weather and climate, geographic information systems, geology, earth sciences, environmental design and psychology (bernardes et al., 2020). numerous undergraduate and graduate students have been involved in the uas data acquisition, image processing and the development of content for extended reality demonstrations (bernardes et al., 2018). current research is being conducted to assess the effectiveness of the use of extended reality to enhance the understanding of complex geospatial concepts and understanding of the physical environment. indeed, the development of the 3dig has led to the creation of the disruptive geospatial technologies laboratory within the uga center for geospatial research that further explores cutting-edge technologies for data acquisition, manipulation, teaching, learning and discovery. these technologies have been developed, implemented or modified by 23 students at uga, through a variety of on-the-job training and mentorship experiences. see digtl (2020) for additional information and updates on projects, research and teaching tools addressing critical issues in human and environment relationships. the 3dig system in research and outreach components have demonstrated both the advantages and limitations of advanced geovisualization techniques. trade-offs of enhanced and multi-dimensional visualization of our environment must be weighed against the cost of extended reality devices, the need for advanced skills in computer programming and additional training of instructors. sergio bernardes et al / geosi vol 5 no 3 (2020) 352-363 361 4. conclusion in conclusion, the 3dig system developed at the university of georgia combines geospatial technologies with photogrammetry and emerging visualization techniques to spark excitement, foster engagement and create active learning environments. emerging technologies provide opportunities for research, education and outreach that are rooted in the visual interpretation of aerial imagery and combined with technologies for state-of-the-art training, enhanced geovisualization and participatory community involvement. conflict of interest the authors declare that there is no conflict of interest with any financial, personal, or other relationships with other people or organizations related to the material discussed in the article. acknowledgements the assistance of students at the university of georgia who have volunteered their time during several phases of the project is gratefully appreciated. this research was supported by the uga center for teaching and learning, the uga center for research and education at wormsloe and the wormsloe foundation. references anson, a. (1968). photographic interpretation from color aerial photographs. manual of color aerial photography. first edition. , virginia : am. soc. photogrammetry, falls church. bainbridge, w. s. (2007). the scientific research potential of virtual worlds. science, 317(5837), 472-476. bernardes, s., howard, a., mendki, a., walker, a., bhanderi, d., le, l., ... & rukangu, a. (2019). innovative technologies in teaching and learning: incorporating recent developments in virtual and augmented reality into active learning at the university of georgia. agufm, 2019, ed11b-0873. bernardes, s., madden, m., knight, a., neel, n., morgan, n., cameron, k., & knox, j. (2018). a multi-component system for data acquisition and visualization in the geosciences based on uavs, augmented and virtual reality. isprs international archives of the photogrammetry, remote sensing and spatial information sciences, xlii–4, 45–49. https://doi.org/10.5194/isprs-archives-xlii-4-45-2018. sergio bernardes et al / geosi vol 5 no 3 (2020) 352-363 362 campbell, j. b., & wynne, r. h. (2011). introduction to remote sensing. new york : guilford press. çöltekin, a., lochhead, i., madden, m., christophe, s., devaux, a., pettit, c., … hedley, n. (2020). extended reality in spatial sciences: a review of research challenges and future directions. isprs international journal of geo-information, 9(7), 439. https://doi.org/10.3390/ijgi9070439. colwell, r. (1997). history and place of photographic interpretation. chapter 1, in, philipson, warren r. (ed-in-chief), manual of photographic interpretation, second edition, pp. 347. maryland: american society for photogrammetry and remote sensing. digtl. (2020). disruptive geospatial technologies laboratory (digtl), center for geospatial research, department of geography, university of georgia, athens, georgia, http://www.cgr.uga.edu/labs/digtl/ and http://www.cgr.uga.edu/labs/digtl/interactions.html, last accessed, 14 november 2020. hoffman, r. r. (2018). cognitive and perceptual processes in remote sensing image interpretation. in remote sensing and cognition (pp. 15-32). florida : crc press. jensen, j.r. (2007). remote sensing of the environment: an earth resource perspective. second edition, new jersey : pearson prentice hall, upper saddle river. lillesand, t., kiefer, r. w., & chipman, j. (2015). remote sensing and image interpretation. new york : john wiley & sons. maceachren, a. m., & taylor, d. f. (eds.). (2013). visualization in modern cartography. oxford: elsevier. madden, m., jordan, t., & dolezal, j. (2006). geovisualization of vegetation patterns in national parks of the southeastern united states. in geographic hypermedia (pp. 329345). , berlin, heidelberg : springer. madden, m., jordan, t., kim, m., allen, h., & xu, b. (2009). integrating remote sensing and gis: from overlays to geobia and geovisualization. manual of geographic information systems, 701-720, maryland : bethesda. milgram, p., & kishino, f. (1994). a taxonomy of mixed reality visual displays. ieice transactions on information and systems, 77(12), 1321-1329. olson, c. e. (1960). elements of photographic interpretation common to several sensors. photogrammetric engineering, 26(4), 651-656. petrasova, a., harmon, b., petras, v., & mitasova, h. (2015). tangible modeling with open source gis (p. 135). cham: springer international publishing. https://doi.org/10.3390/ijgi9070439 http://www.cgr.uga.edu/labs/digtl/ http://www.cgr.uga.edu/labs/digtl/interactions.html sergio bernardes et al / geosi vol 5 no 3 (2020) 352-363 363 sabins, f. f. (2007). remote sensing: principles and applications. , illinois: waveland press. slocum, t. a., blok, c., jiang, b., koussoulakou, a., montello, d. r., fuhrmann, s., & hedley, n. r. (2001). cognitive and usability issues in geovisualization. cartography and geographic information science, 28(1), 61–75. https://doi.org/10.1559/152304001782173998. stefanakis, e., & peterson, m. p. (2006). geographic hypermedia. in geographic hypermedia (pp. 1-21). berlin : springer. white, r. a., coltekin, a., & hoffman, r. r. (eds.). (2018). remote sensing and cognition: human factors in image interpretation. florida : crc press. https://doi.org/10.1559/152304001782173998 80 qamar zaman and shahid nawaz khan/ geosi vol 5 no 1 (2020) 80-91 the application of geographic information system (gis) and remote sensing in quantifying snow cover and precipitation in kabul basin qamar zaman* and shahid nawaz khan institute of geographical information systems, school of civil and environmental engineering, national university of sciences and technology, islamabad, 44000, pakistan *corresponding author : qamar.civil@suit.edu.pk received 16 december 2019/ revised 25 january 2020/ accepted 31 january 2020/ published 10 april 2020 abstract water resources availability is very important to social and economic well-being of the people and has huge impacts on the socio-economic scenarios of a country. precipitation and snow cover area assessment is some of the major inputs in hydrologic modelling and also for assessing and managing water resources in a basin. the change in the water availability in a basin has huge socio-economic impacts because of the water usage for food production, industries, and many others. the main aim of this study was to measure the snow cover area and precipitation from 2001 to 2015 in the kabul basin. moderate resolution image spectroradiometer (modis) and tropical rainfall measuring mission (trmm) data were used to study snow cover area and precipitation respectively during 2001-2015. 8-day snow cover product for 15 years (january) was used to analyse the snow cover while monthly data of trmm (3b43) were used to analyse the rainfall from 2001-2015. different image processing techniques were applied on the data retrieved using gis and remote sensing softwares. initially, sca was seen increasing, but during the last 3-4 years, it kept decreasing gradually. rainfall was initially recorded as low, while later on, it was recorded high and reached the highest during 2010. keywords: modis; snow cover; trmm; precipitation; kabul basin; remote sensing 1. introduction snow cover area is an important component of a regional as well as global climate system and also a critical storage system of fresh water on the surface (larson et al., 2009). equally, precipitation is also one of the important input parameters for land surface hydrological modelling of a basin and its quantification is necessary for assessing available water resources (zhang & srinivasan, 2010). both snow cover area estimation and precipitation quantification, thus, are important to assess the water resources. traditionally, snow cover is measured by monitoring the snow physically in a network which gives accurate information about the snow cover. however, the method is not feasible for long range measurement because of its spatial scale, i.e. the sparse network geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.5 no. 1 (2020), 80-91, april, 2020 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v5i1.14896 accredited by the ministry of research , technology , and higher education of the republic of indonesia, no. 30/e/kpt/2019. https://jurnal.unej.ac.id/index.php/geosi https://drive.google.com/file/d/1rsnvas6cuhowhl5bj87cl2l6k5dqz7s6/view 81 qamar zaman and shahid nawaz khan/ geosi vol 5 no 1 (2020) 80-91 having very few stations as compared to the area which is unable to deliver the amount of information needed for the accurate snow cover estimation (atif et al., 2015). similarly, rainfall is measured using rain gauges which give information about variations in trends o f precipitation monthly. nevertheless, because the rain gauges cannot be deployed in remote places and some areas are difficult to reach, they account for 25-30% of the surface of the earth (new et al., 2001). therefore, a mechanism is needed to monitor the snow cover and rainfall at a large spatial and temporal scale remotely (ershadi et al., 2005). the modern satellite system in space has the capabilities to monitor different natural and human induced dynamics at different spatial, spectral and temporal scale (daly et al., 2012). these satellite systems operate round the clock and provide the captured data of almost all of the world for, mostly, free or at some nominal price. the data retrieved from these systems can be analysed for making policy decision including water supply and demand. the moderate resolution imaging spectroradiometer (modis) which was launched in 1999 has the capabilities to study the earth’s geophysical phenomena, which include mapping the areal extent of snow using snowmap algorithm (hall et al., 1995). the snowmap algorithm was developed by using thematic mapper data to automatically map the area extent of the snow using different modis bands on a daily basis. different snow products of modis are available at national snow and ice data center from september, 13, 2000 to date which include daily and 8 days snow cover (hall et al., 2001). tropical rainfall measuring mission (trmm) is a joint mission between nasa of united states of america and national space development agency of japan, which measures the precipitation and energy exchange of tropical and subtropical regions (kummerow et al., 1998). trmm microwave imager (tmi) and visible and infrared radiometer system (virs) are primary rainfall measurement instrument on board on trmm. different products of trmm are available online, including daily 3b42 and monthly 3b43 products. previous related studies argue that the relationship between snow, global warming, and land use can influence the changes in landforms (beato bergua et al., 2019). snowfall can be identified by using a two-dimensional model, so that disaster risk reduction can be optimized (nakamura et al., 2019). snowmelt is affected by slopes and causes high infiltration (miao et al., 2019). modis-based vegetation maps can be used to calculate the capacity and intensity of snow in a basin (pyankov et al., 2018). the aster gdam and landsat 8 oli images can be used to analyse the snowfall parameters (kumar et al., 2018). nevertheless, the previous studies did not consider the aspects of rainfall as water 82 qamar zaman and shahid nawaz khan/ geosi vol 5 no 1 (2020) 80-91 resources in the snow area, therefore, it is necessary to study the use of gis and remote sensing to improve the quality of water resources. the differences in the rainfall among the regions based on latitude are very important to know in relation to climate change. hence, the main aim of this study was to measure the snow cover area and precipitation from 2001 to 2015 in the kabul basin. 2. methods the kabul river basin has a catchment area of approximately 94,000 sq. kilometers. the river drains two countries, i.e. pakistan and afghanistan, and is located in the northwestern side of pakistan and north eastern side of afghanistan (aziz, 2014). the river kabul flows from east to west, ultimately joining the indus river near attock, in pakistan khyber pakhtunkhwa province from where it finally merges into arabian sea (lashkaripour et al., 2008). many barrages have been constructed on various locations on the river to support the system of extensive agricultural irrigation. the economy of most of the people depends on agriculture. although the basin comprises of 12% area of afghanistan, it has 35% population of afghanistan (vick, 2014). major portion of the population live in the area and, mostly, the population is concentrated along the main courses of the river and adjacent areas where water is available for agriculture the production of agriculture because the main source of income in that area is agricultural production. most of the agriculture is depends on the river and, thus, is located along the adjacent areas where river water is accessible for irrigation purposes. the greater amount of water supplied in the summers results in intensive cropping in the area while some of the areas is also rain fed. in this study, modis data were used for calculating the snow cover area. modis 8 days snow cover product with a spatial resolution of 500 meters, i.e. mod10a2v6, is available at the national snow and ice data center nsidc with a spatial resolution of 500 meters. the 8-daily product is generated from the daily snow cover product mod10a1v6, which in turn is derived from normalised difference snow index ndsi (equation 1). snow cover has a high reflectance rate in visible bands and low reflectance rate in shortwave infrared swir. the normalised difference snow index reveals those differencing high values show snow covered areas. cells having ndsi>=0.4 are considered as the snow covered cells. different remote sensing and gis softwares (table 1) were used for the processing of imagery and estimation of the snow cover area. ndsi= band 4band 6/band 4+ band 6 (1) 83 qamar zaman and shahid nawaz khan/ geosi vol 5 no 1 (2020) 80-91 table 1. tools and data used for sca assessment data/tools details modis snow cover data mod10a2v6 (500 meters) trmm data 3b43 monthly data mm/hr. arcmap 10.1.4 collecting, analyzing, processing, and manipulating satellite imagery modis reprojection tool spectrally subsetting and reprojecting modis data 2.1. reprojection modis data were processed and generated as a gridded output in the sinusoidal sin projection in the hdf format. the modis reprojection tool is used for a number of preprocesses on modis data, including the spatial sub setting, spectral sub setting, format conversion, and geographic transformation to a different coordinate system. mrt was used to spectrally subset the products and retain only those bands which were needed for further processing in the study. mrt was available online for processing modis datasets, in which the data were converted from sinusoidal to projected coordinate system to enable the measurement and then were converted to tiff format so that the other softwares can conveniently read it. 2.2. image processing the aim of image processing using geospatial softwares is to extract the meaningful information from the images. many open sources and commercial geospatial image processing softwares are available to use to process the different types of satellite imagery and extract the meaningful information from it. some of the available softwares are erdas imagine, envi, idrisi, and arcmap. although arcmap is a gis software having more capabilities for vector data processing, still it is used for different kinds of image processing .images preprocessed through mrt were processed in arcmap, where snow cover areas and non-snow cover areas were separated and the final snow cover areas from those images were extracted. 84 qamar zaman and shahid nawaz khan/ geosi vol 5 no 1 (2020) 80-91 2.3. precipitation data acquisition and processing tropical rainfall measuring mission trmm monthly product 3b43 version 7 was used for quantifying liquid precipitation in the study area. these data combined the daily data from trmm and other satellites, and estimated the best possible estimate from the data at temporal resolution of one month. the data acquired from nasa was converted, reprojected, and extracted to study area using different gis softwares. the data were rescaled to 500 meters spatial resolution. many image processing and statistical techniques were applied on the data. trmm 3b43 monthly data iswere available in unit of mm/hr,. which was then converted to mm/day, and subsequently to mm/month. annual accumulated data as well as annual mean were generated using those monthly data. 2.4. snow cover area (sca) and precipitation quantification snow cover and non-snow cover areas were separated in the modis product. moreover, the snow cover area was calculated for each image, which was further averaged over the month by using all the data acquired and processed. similarly, rainfall was quantified for the study area by using monthly and annually accumulated and mean data, using different techniques. 2.5. snow cover area (sca) and precipitation maps the snow cover areas were estimated using 8-day modis snow cover product and the maps were also generated at the same interval. four maps for each month were generated, i.e. the 1st to 8th day, 9th-17th day, 18th -25th day, and last from 25th to 3rd day of next month, which was the 3rd of february. the precipitation data was averaged manually and annual accumulated maps were produced by arcmap. 3. results and discussion the results show that during the initial years i.e. 2001 onwards, there was an increase in the snow cover area which could be seen up to 2006 and 2007. there were also minor increase and decrease in the snow cover area in the successive years up to 2011. from 2012 onwards, a gradual decrease could be seen in the snow cover area which was 65,285 sq. kilometers in 2012, 63,244 sq. kilometers in 2013, 56716 sq. km in 2014, and 50,935 sq. km in 2015. researchers pointed out that the decrease in snow cover area in the next 10-15 years in pakistan will be considerable (zahid & rasul, 2011). it might not be considerably noted in the initial years, but it was observed during the last 4 years, from 2012 to 2015. from 2008 up to 2011, an irregular pattern was observed in the snow cover change, which was neither 85 qamar zaman and shahid nawaz khan/ geosi vol 5 no 1 (2020) 80-91 decreasing gradually nor increasing gradually but increased somewhere and decreased at other times. as shown in table 1 and figure 1, the snow over area gradually increased from 50,856 sq. km in 2001 to 61,406 sq. km in 2006. the snow cover changed irregularly during 2007 up to 2011, which sometimes increased or decreased. this might also be attributed to the accuracy of the data used for the study. the snow cover area was recorded the highest in 2012, which was 65,285 sq. km, from where it went on decreasing gradually towards 2015. table 2. accumulated snow cover area estimated from modis snow cover product year snow cover area (km2) year snow cover area (km 2) 2001 50856 2009 57812 2002 50721 2010 51286 2003 54307 2011 45517 2004 55629 2012 65285 2005 57201 2013 63244 2006 61406 2014 56716 2007 61221 2015 50925 2008 49599 table 2 shows that there are fluctuations in the area covered by snow. this was due to changes in the rainfall and significant temperature differences. in 2012 and 2013, the area covered was very large due to the influence of changes in the duration and pattern of the rainy season. table 3. mean annual rainfall of kabul basin estimated from trmm year mean annual rainfall (mm) year mean annual rainfall (mm) 2001 260.00 2009 599.34 2002 388.73 2010 676.43 2003 535.31 2011 584.91 2004 472.43 2012 556.61 2005 562.78 2013 648.75 2006 521.37 2014 654.67 2007 518.39 2015 642.01 2008 566.19 86 qamar zaman and shahid nawaz khan/ geosi vol 5 no 1 (2020) 80-91 the mean annual rainfall varied from 260 mm to 676 mm as shown in table 3. in the initial years, just like the snow cover, less rainfall was recorded and was restively larger in the following years. the year 2010 received the largest amount of rainfall in all 15 years which caused pakistan to suffer devastating floods in areas of khyber pakhtunkhwa, where large amount of crops were destroyed and suffered from around 1100 causalities (sayama et al., 2018). the average rainfall in table 3 does not directly affect the snow cover,. this is because the intensity of the rain also greatly influences the existence of run off. in areas with high rainfall intensity, rain will erode soil material quickly with higher exogenous power. 87 qamar zaman and shahid nawaz khan/ geosi vol 5 no 1 (2020) 80-91 figure 1. the expansion of the area covered by snow figure 1 shows the expansion of the area covered by snow over time. it shows that there are human interventions on the environment that cause climate change and snow expansion. areas that have steep slopes will be a source of melt snow that flows with high intensity to other areas; hence, there is a need for conservation efforts to overcome this. snow non snow 0 km 200 km 88 qamar zaman and shahid nawaz khan/ geosi vol 5 no 1 (2020) 80-91 when the rainy season is too short, snowmelt can cause changes in landforms with different impacts on the environment. the result of the previous research that can be compared to the results of this study is the need for water that comes from snowmelt when summer is very high, as it shows that snow has an impact on people's lives during the summer (amstrong et al., 2019). microclimate greatly influences snow characteristics in an area, so the is a need for differing planning to cope with too high rainfall (plach et al., 2019). meltsnow is the most influential source of irrigation in the area before the rainy season (biemans., 2019). meltsnow can increase run off so that it will significantly cause changes in the landform (il jeong & sushama, 2018). higher soil erosion occurs when there is snow when compared to the rainy season, so there needs to be a different conservation effort for the two seasons (wu et al., 2018). compared to the results of the previous studies, the advantage of this study lies on the temporal comparison in the low latitude region. with different rainfall, it is necessary to have different conservation in each watershed in this region. areas with higher sun exposure will affect snow characteristics, especially the ones which exposed to erosion and run off. watershed conditions that have a varied microclimate will have an impact on the diversity of vegetation and human activities. 4. conclusion remote sensing satellites have the capabilities to sense different phenomenon on the surface of earth from space. their data availability, reliability, and cost have defeated many conventional techniques to acquire data for analysing different processes on the surface of earth. it is also ssimilar to the case of snow cover area aassessment and rainfall quantification, the conventional techniques may be accurate and useful, yet they are quite expensive and, sometimes, unreliable because of human induced factors or some other effects. although satellite images are free of charge and are available on the daily basis, still, the choice of selecting the specific source of data needs much analysis and study on the analyst’s side. thise study found no considerable change in the snow cover area in the initial years, but later on in the last 3-4 years, it found a gradual decrease in the snow cover which might be due to the changing snow cover accumulation periods. related to rainfall, variations were found in which less rainfall were recorded in the initial years and, later on in 2010, the highest rainfall was recorded in which pakistan experienced devastating floods. 89 qamar zaman and shahid nawaz khan/ geosi vol 5 no 1 (2020) 80-91 conflict of interest the authors declare that there is no conflict of interest with any financial, personal, or other relationships with other people or organizations related to the material discussed in the article. acknowledgements we would like to express our sincere gratitude to dr. javed iqbal, professor and the head of institute of geographical information system department, scee, nust for his continuous support and guidance throughout the study. we would also like to thanks mr. junaid aziz khan, the lecturer, of institute of geographical information systems, nust for his support and guidance throughout the period of this study. references armstrong, r. l., rittger, k., brodzik, m. j., racoviteanu, a., barrett, a. p., khalsa, s. -. s., . . . armstrong, b. (2019). runoff from glacier ice and seasonal snow in high asia: separating melt water sources in river flow. regional environmental change, 19(5), 1249-1261. doi:10.1007/s10113-018-1429-0 atif, i., mahboob, m. a., & iqbal, j. (2015). snow cover area change assessment in 2003 and 2013 using modis data of the upper indus basin, pakistan. journal of himalayan earth sciences, 48(2), 117-128. aziz, a. (2014). rainfall-runoff modeling of the trans-boundary kabul river basin using integrated flood analysis system (ifas). pakistan journal of meteorology, 10(20). beato bergua, s., poblete piedrabuena, m. á., & marino alfonso, j. l. (2019). snow avalanches, land use changes, and atmospheric warming in landscape dynamics of the atlantic mid-mountains (cantabrian range, nw spain). applied geography, 107, 3850. doi:10.1016/j.apgeog.2019.04.007 biemans, h., siderius, c., lutz, a. f., nepal, s., ahmad, b., hassan, t., . . . immerzeel, w. w. (2019). importance of snow and glacier meltwater for agriculture on the indogangetic plain. nature sustainability, 2(7), 594-601. doi:10.1038/s41893-019-0305-3 daly, s. f., vuyovich, c. m., deeb, e. j., newman, s. d., baldwin, t. b., & gagnon, j. j. (2012). assessment of the snow conditions in the major watersheds of afghanistan using multispectral and passive microwave remote sensing. hydrological processes, 26(17), 2631-2642. ershadi, a., khiabani, h., & lorup, j. k. (2005). applications of remote sensing, gis and river basin modelling in integrated water resource management of kabul river basin. in icid 21st european regional conference. hall, d. k., riggs, g. a., & salomonson, v. v. (1995). development of methods for mapping global snow cover using moderate resolution imaging spectroradiometer data. remote sensing of environment, 54(2), 127-140. 90 qamar zaman and shahid nawaz khan/ geosi vol 5 no 1 (2020) 80-91 hall, d. k., riggs, g. a., & salomonson, v. v. (2001). mapping global snow cover using moderate resolution imaging spectroradiometer (modis) data. glaciological data, 33. il jeong, d., & sushama, l. (2018). rain-on-snow events over north america based on two canadian regional climate models. climate dynamics, 50(1-2), 303-316. doi:10.1007/s00382-017-3609-x kumar, s., srivastava, p. k., & snehmani. (2018). geospatial modelling and mapping of snow avalanche susceptibility. journal of the indian society of remote sensing, 46(1), 109-119. doi:10.1007/s12524-017-0672-z kummerow, c., barnes, w., kozu, t., shiue, j., & simpson, j. (1998). the tropical rainfall measuring mission (trmm) sensor package. journal of atmospheric and oceanic technology, 15(3), 809-817. larson, k. m., gutmann, e. d., zavorotny, v. u., braun, j. j., williams, m. w., & nievinski, f.g. (2009). can we measure snow depth with gps receivers?. geophysical research letters, 36(17). lashkaripour, g. r., & hussaini, s. a. (2008). water resource management in kabul river basin, eastern afghanistan. the environmentalist, 28(3), 253-260. miao, f., wu, y., li, l., liao, k., & zhang, l. (2019). risk assessment of snowmelt -induced landslides based on gis and an effective snowmelt model. natural hazards, 97(3), 1151-1173. doi:10.1007/s11069-019-03693-2 nakamura, k. (2019). implementation and demonstration of a system for the forecasting of surface avalanche potential caused by snowfall from a cyclone. journal of disaster research, 14(9), 1201-1226. doi:10.20965/jdr.2019.p1201 new, m., todd, m., hulme, m., & jones, p. (2001). precipitation measurements and trends in the twentieth century. international journal of climatology, 21(15), 1889-1922. plach, j., pluer, w., macrae, m., kompanizare, m., mckague, k., carlow, r., & brunke, r. (2019). agricultural edge-of-field phosphorus losses in ontario, canada: importance of the nongrowing season in cold regions. journal of environmental quality, 48(4), 813821. doi:10.2134/jeq2018.11.0418 pyankov, s. v., shikhov, a. n., kalinin, n. a., & sviyazov, e. m. (2018). a gis-based modeling of snow accumulation and melt processes in the votkinsk reservoir basin. journal of geographical sciences, 28(2), 221-237. doi:10.1007/s11442-0181469-x sayama, t., ozawa, g., kawakami, t., nabesaka, s., & fukami, k. (2012). rainfall–runoff– inundation analysis of the 2010 pakistan flood in the kabul river basin. hydrological sciences journal, 57(2), 298-312. vick, m. j. (2014). steps towards an afghanistan–pakistan water-sharing agreement. international journal of water resources development, 30(2), 224-229. wu, y., ouyang, w., hao, z., yang, b., & wang, l. (2018). snowmelt water drives higher soil erosion than rainfall water in a mid-high latitude upland watershed. journal of hydrology, 556, 438-448. doi:10.1016/j.jhydrol.2017.11.037 91 qamar zaman and shahid nawaz khan/ geosi vol 5 no 1 (2020) 80-91 zahid, m., & rasul, g. (2011). frequency of extreme temperature and precipitation events in pakistan 1965–2009. sci. int.(lahore), 23(4), 313-319. zhang, x., & srinivasan, r. (2010). gis-based spatial precipitation estimation using next generation radar and raingauge data. environmental modelling & software, 25(12), 1781-1788. md naimur rahman / geosi vol 4 no 3 (2019) 217-229 217 urban expansion analysis and land use changes in rangpur city corporation area, bangladesh, using remote sensing (rs) and geographic information system (gis) techniques md naimur rahman department of geography and environmental science, begum rokeya university rangpur city bypass, rangpur 5400, bangladesh email: 01naimur@gmail.com received 24 september 2019/ revised 27 october 2019/ accepted 6 november 2019/ published 1 december 2019/ available online 25 november 2019 abstract this study aim to attempt mapping out the land use or land cover (lulc) status of regional project coordination committee (rpcc) between 2009-2019 with a view of detecting the land consumption rate and the changes that has taken place using rs and gis techniques; serving as a precursor to the further study on urban induced variations or change in weather pattern of the cityn rangpur city corporation(rcc) is the main administrative functional area for both of rangpur city and rangpur division and experiencing a rapid changes in the field of urban sprawl, cultural and physical landscape,city growth. these agents of land use or land cover (lulc) varieties are responsible for multi-dimensional problems such as traffic congestion, waterlogging, and solid waste disposal, loss of agricultural land. in this regard, this study fulfills lulc changes by using geographical information systems (gis) and remote sensing (rs) as well as field survey was conducted for the measurement of change detection. the sources of data were landsat 7 etm and landsat 8 oli/tirs of both c1 level 1. then after correcting the data, geometrically and radiometrically change detection and combined classification (supervised & unsupervised) were used. the study finds lulc changes built-up area, water source, agricultural land, bare soil in a change of percentage is 17.23, 2.58, -9.94, -10.19 respectively between 2009 and 2019. among these changes, bare soil is changed to a great extent, which indicates the expansion of urban areas is utilizing the land to a proper extent. keywords: urban expansion; land use; land cover; remote sensing; geographic information system (gis); rangpur city corporation(rcc). 1. introduction bangladesh is a developing country with the rapid growth of the population. rangpur is also a fast-growing city in the field of urbanization, with having a population of 2.96 million. because of the fastest population growth lulc also changing the emphasizes function of geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.4 no. 3 (2019), 217-229, december, 2019 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v4i3.13921 accredited by the ministry of research, technology and higher education of the republic of indonesia, no. 30/e/kpt/2019. md naimur rahman / geosi vol 4 no 3 (2019) 217-229 218 urbanization. a satellite image is carrying many more essentialities for the proper and quick planning of lulc. for this reason, the field surveying method is considering time-consuming and costly, which is replacing by rs techniques. fasal (2000) asserted the nature of land use changes , location of agricultural land losses and for the reason of urbanization the supply of higher quality of agricultural activities is reducing. remote sensing satellites are playing a vital role in mapping land use and land cover changes and infrastructural development for several past recent years (arimoro et al., 2003). but in rcc no such application is implemented for the detection and assessment of these types of operational work (dewan and yamaguchi, 2009). land use changes arising from agriculture, pasturing, urbanization, bare soil and deforestation are some of the responsible factors to land cover changes in rcc. these changes in lulc reflect on the growth of population, consumption of land and the local climate. expansion of rcc has resulted not only in the depletion of natural resources, but a deterioration of the environment. agriculturally productive land, forestland, bare land have been transformed into different commercial, residential and other uses. the lulc is the result of social, economic, environmental phenomenon and their perspective of utilization. the collection of remotely sensed data contributes to the synoptic assessments of the function of earth-system, patterning, and change at local, regional , and global scales over time (rajeshwari, 2006). however, the objective of this study is to attempt mapping out the lulc status of rpcc between 2009-2019 with a view of detecting the land consumption rate and the changes that has taken place using rs and gis techniques; serving as a precursor to the further study on urban induced variations or change in weather pattern of the city. the changes of rapid land use are the cause of a growing population , which is reducing another area of interest like natural vegetation (nicolson, 1987). the urban centers are increasing in population , but a two-fold conversion is undergoing for the pre-urban areas; arable and non-arable land both are providing increasingly numbered of establishments such as commercial, industrial and residential (heimlich and anderson, 2001). kalnay and cai (2003) assessed that the urban area and surroundings could be altered by the local climate, which is the cause of urban expansion. instead of using traditional approaches, satellite remote sensing is essentially monitoring the change of land use with the facilities of high resolution which is associated with lower cost (belal and moghanm, 2011). md naimur rahman / geosi vol 4 no 3 (2019) 217-229 219 the lulc maps also revealed an increase in land reclamation and have an environmental impact (fellati et al, 2017; risma et al, 2019; djimadoumngar, k.-n., & adegoke, j, 2018 ). al rifat and liu (2019) found that new urban lands were generated away from the coast. edwards et al (2019) found that a restrictive zoning regime has controlled urban sprawl. the informal settlements continue to develop rapidly in each city (park et al, 2019). urban area planning must consider the development of the city vertically (he et al, 2019). land use mapping will be very helpful for proper urban area planning (navale and mhaske, 2019). previous research has not analyzed urban expansion and its relationship with coporation area, so this research has a novelty that emphasizes the interrelationship between urban expansion, land use change, corporation area , and the use of remote sensing and geographical information systems. this study aims to attempt mapping out the lulc status of rpcc between 2009-2019 with a view of detecting the land consumption rate and the changes that have taken place using rs and gis techniques 2. methods this study utilizes data for the measurement of lulc changes. remotely sensed data landsat 8 and landsat 7 of both c1 level 1 were used for the lulc change detection in between the year of 2019 and 2009 (a ten year time span). spatial characteristics of these data having the below approaches ( see table 1). in addition, these data were collected from earthexplorer.usgs.gov whist path and row were 138 and 042. table 1: spatial characteristics of data ( used) instrument month/ year of image sensors spatial resolution radiometric resolution (bit) landsat 7 february 2009 etm+ 30 16 landsat 8 may 2019 oli/tirs 30 12 universal transverse mercator (utm) was used for the collected satellite images for the map projection within zone 46 n-datum and of the co-ordinate system world geodetic system (wgs) 1984 and the pixel size is 30 meters. for the extraction of study area of rcc shape file of gis was used with having the same projection of utm and wgs 1984 , which was georeferenced. then images were taken by raster processing tool under data management tool md naimur rahman / geosi vol 4 no 3 (2019) 217-229 220 of arctoolbox in arcgis 10.5. and finally, the image classification was conducted by the combination of supervised and unsupervised classification. an extensive field survey was performed of the rcc by using gps (global positioning system), earlier the preprocessing and classification of satellite imagery. gps was used for scaling the satellite image data by comparing the field data. and this fieldwork was done in the mid of february 2019. rpcc established in 2012, which was previously known as rangpur pourasova ( established 1986), with having 442 village and 112 mouza. rpcc geographically located in between 25˚38' and 25˚52' north latitudes and 89˚05' and 89˚20' east longitudes. it is bounded by nilphamari and lalmonirhat district on the north, on the south gaibandha, on the east kurigram and dinajpur on the east with having the total area of 205.70 square kilometers ( figure 2). and population growth change of rangpur is +1.98 per year from 2001 to 2011 ; which was increased 865,927 in the year of 2014 (bbs 2015). figure 1. study area md naimur rahman / geosi vol 4 no 3 (2019) 217-229 221 4. results and discussion in this section, results are shown on the basis of lulc distribution, area measurement, percentage of covered area, change detection and changing pattern. the city of rangpur gets a haphazard expansion of urban area , which is the result of conversion of agricultural and bare land. during the period of 2009 and 2019 due to the urbanization and the cause of rangpur pourosovaturning into rcc in 2012 has made the city expanded largely into an urban area which is 5670 hectares of 17.53 percent of total area (table 3). the distribution of lulc changes rapidly in the sector of a built up area which is nearly two times higher than in 2019 also, the noticeable decreases land is agricultural which is a significant indication of 10% loss. but it decreased to a great extent of bare soil from 3439 to 145 hectares(table 2). these changes define the urban expansion where agricultural and bare soil is used to urbanized the areas. as the city population is increasing, the city has been expanded extensively to accommodate the increasing population compared to its early stage the cities spatial expansion is the modification of several constrained physical factors. however, the loss of natural resources is the cause of the development. the lulc pattern changes spatially from 2009 to 2019 (figure 3 & 4). earlier in 2009 built up area was congested at the center where other parts also carried it haphazardly in the north west, north south direction. in 2019 the urban area expanded largely northward, westward and southward where the direction of eastward expansion was very low compared with them respectively. the lulc map interpretation in between 2009 and 2019 shows that rcc is expanding in all of the following directions northwest, south-west and southern parts by filling up low lying areas. the major perspective of expanding these areas is the increasing of residential, public and privet structural development. the maximum loss of agricultural land and bare soil provides the information of the pressure of urban expansion of it. the study area urbanization is rapidly growing and if it continues it will decrease land cover areas 35.06 percent within the next 20 years which will lead to diversified and uneven expansion like present times in 2019. the contributing factors of urban sprawl are increased amount of population, poor land use policy, low land, unplanned housing md naimur rahman / geosi vol 4 no 3 (2019) 217-229 222 and expansion of industrial areas, poverty, absence of multiuse of urban areas which is creating the slums and squatters with decreasing food safety due to the loss of agricultural land. these diversification is negatively affecting of both natural environment and human health as well as for the development of near future perspectives. table 2. land use land cover distribution (areas in hectares) figure 2. land use map 2009 classification category 2009 2019 area(ha) area covered(%) area(ha) area covered(%) built up area 3468 10.73 9138 28.26 water source 1973 6.10 2805 8.68 agricultural land 23453 72.55 20245 62.61 bare soil 3439 10.64 145 0.45 total 32333 100 32333 100 md naimur rahman / geosi vol 4 no 3 (2019) 217-229 223 figure 3: land use map 2019 table 3: lulc change of rcc and its environs classification category 2009 area(ha) 2019 area (ha) difference in area(ha) difference in area(%) built up area 3468 9138 5670 17.53 water source 1973 2805 832 2.58 agricultural land 23453 20245 -3208 -9.94 bare soil 3439 145 -3294 -10.19 md naimur rahman / geosi vol 4 no 3 (2019) 217-229 224 figure 4. lulc change detection between 2009 & 2019 results of table 2 and figure 3, 4 makes an evidence of congestion of the city and haphazardly increasing number of built up area which includes residential, commercial and services, industrial, transportation, roads, mixed urban, and other urban areas within the percentage of 17.53(5670 ha) where with the same increasing trend water source also got improvement. the responsible factors for these urban expansions are mainly population growth and haphazard development of residential, industrial as well as public infrastructure. and the improvement and increased amount of water bodies proves that permanent water sources like river, permanent open water, lakes, ponds and reservoirs are extended whereas temporal or seasonal water sources like permanent and seasonal wetlands, marshy land, swamps have been decreased. 3208 hectares of agricultural land are negatively increased due to the positively extent of built up area of 5670 hectares where agricultural land indicates the agents of both cultivated and planted trees like crop fields, fallow lands , vegetable lands, roadside planted trees, mixed forest lands, homestead forest. the bare soil is providing space both for the built up area and permanent water source and for this reason, it is increased negatively of 10.19 percent of 145 hectares of the 10 years span of time. in a very recent period, bare soil indicates exposed soils, sand fill, landfill sites, and areas of active excavation. this reduction of agricultural land and bare soil is leading the fact of urbanization rapidly. lulc change detection represents the result of table 3 and figure 5 where rapid change is noticed in the factors of built up area and bare soil which is about 27.72. their individual 0 5000 10000 15000 20000 25000 built up area water source agricultural land bare soil 2009 2019 md naimur rahman / geosi vol 4 no 3 (2019) 217-229 225 approximate change indicates the built up area is most commonly responsible for this rapid change. beyond the changing pattern of built up area rapid growth of the population of the city( see figure 2) is playing an essential role. bare land is negatively changed of 10.19 , which is the indication of land use efficiency. figure 5. gdp from the sector of agriculture and forestry loss of agricultural land is the reason of gradual loss of gdp as it is the field of second largest source of gdp after manufacturing ( 20.17% gdp). as water source is increased of 2.58 percent so that agricultural activity could be benefited from it and also fisheries sector is improving for the reason of available water source (field survey). for the food safety and economic growth (see figure 6) agricultural land carries several responsibilities in bangladesh agricultural production and 84% of rural people directly or indirectly engaged with agriculture ( uddin, 2015). but it is decreased in rpcc of about 10 percent which is an alarming rate for the food safety. the results of previous study indicate the suitability of the proposed indices to discriminate between urban areas, bare soil in arid, water balance, population data and semi-arid climates (rasul et al, 2018; schilling et al, 2008; nong et al; 2015). matlhodi et al (2019) found that the need for monitoring in the catchment area to avoid land degradation. remote sensing can analyze precisely the relationship between urbanization and groundwater quality (elbeih and 0 2 4 6 8 10 12 14 16 agriculture & forestry gdp md naimur rahman / geosi vol 4 no 3 (2019) 217-229 226 el-zeiny, 2018). there is a negative impact on land changes to water quality of lake (im et al, 2014). quality water needs greatly affect patterns of land change (mondal et al, 2014). the increase in livestock has a negative impact on water quality (fucik et al, 2014). the results of the above studies are different from the results of this study. these differences are found in studies related to urban expansion. the impact of these findings is the need for policies related to urban expansion related to deforested land use. the advantage of this research compared to previous research is the existence of findings related to urban area planning related to lulc changes built up area, water source, agricultural land, bare soil 4. conclusion this study showed that the indication of the potential use of gis and rs technique for obtaining the objective specific measurement of rcc. the uneven and haphazard increasing of settlement, industrial, and commercial infrastructure are rapid, which is the indication of loss of agricultural land and bare soil. but this study also finds that the source of water is increased so this could be an indication of future development of agricultural land. and proper management of urban expansion must be implemented for the quality of cultivation; the separate zonation for the expansion of urban infrastructure could also be conducted. loss of agricultural land could be covered through multi structural use of existing agricultural and bare land with using the available water source. the extended recommendation proposes a future course of action for the field study to identify the category of several spheres of lulc changes. conflict of interest the author declares that there is no conflict of interest with any financial organization regarding the material discussed in the article. references al rifat, s. a., & liu, w. (2019). quantifying spatiotemporal patterns and major explanatory factors of urban expansion in miami metropolitan area during 1992-2016. remote sensing, 11(21) doi:10.3390/rs11212493 md naimur rahman / geosi vol 4 no 3 (2019) 217-229 227 arimoro ao, fagbeja ma, eedy w. (2002). the need and use of geographic information systems for environmental impact assessment in africa: with example from ten years experience in nigeria. ajeam/ragee, 4(2), 16-27. belal, a.a. and moghanm, f.s. (2011).detecting urban growth using remote sensing and gis techniques in al gharbiya governorate, egypt.the egyptian journal of remote sensing and space science, 14, 73-79. http://dx.doi.org/10.1016/j.ejrs.2011.09.001 dewan, a.m. and yamaguchi, y. (2009). using remote sensing and gis to detect and monitor and use and land cover change in dhaka metropolitan of bangladesh during 1960-2005. environmental monitor assessment, 150, 237249. retrieved from http://dx.doi.org/10.1007/s10661-008-0226-5 djimadoumngar, k.-n., & adegoke, j. (2018). satellite-based assessment of land use and land cover (lulc) changes around lake fitri, republic of chad. journal of sustainable development, 11(5), 71. doi:10.5539/jsd.v11n5p71 edwards, b., frasch, t., & jeyacheya, j. (2019). evaluating the effectiveness of land-use zoning for the protection of built heritage in the bagan archaeological zone, myanmar—a satellite remote-sensing approach. land use policy, 88 doi:10.1016/j.landusepol.2019.104174 fallati, l., savini, a., sterlacchini, s., & galli, p. (2017). land use and land cover (lulc) of the republic of the maldives: first national map and lulc change analysis using remotesensing data. environmental monitoring and assessment, 189(8). doi:10.1007/s10661017-6120-2 fučík, p., novák, p., & žížala, d. (2014). a combined statistical approach for evaluation of the effects of land use, agricultural and urban activities on stream water chemistry in small tile-drained catchments of south bohemia, czech republic. environmental earth sciences, 72(6), 2195-2216. doi:10.1007/s12665-014-3131-y elbeih, s. f., & el-zeiny, a. m. (2018). qualitative assessment of groundwater quality based on land use spectral retrieved indices: case study sohag governorate, egypt. remote sensing applications: society and environment, 10, 82-92. doi:10.1016/j.rsase.2018.03.001 fasal, s. (2000). urban expansion and loss of agricultural land – a gis based study of saharanpur city, india. environment and urbanization, 12(2), 133 – 149 he, s., wang, x., dong, j., wei, b., duan, h., jiao, j., & xie, y. (2019). three-dimensional urban expansion analysis of valley-type cities: a case study of chengguan district, lanzhou, china. sustainability (switzerland), 11(20) doi:10.3390/su11205663 md naimur rahman / geosi vol 4 no 3 (2019) 217-229 228 heimlich, r.e and w.d. anderson. (2001). development at the urban fringe and beyond: impacts on agriculture and rural land. 803, economic research service, u.s. department of agriculture, washington d.c., pg 80 im, n., kawamura, k., suwandana, e., & sakuno, y. (2014). monitoring land use and land cover effects on water quality in cheung ek lake using aster images. american journal of environmental sciences, 11(1), 1-12. doi:10.3844/ajessp.2015.1.12 kalnay, e., & cai, m. (2003). impact of urbanization and land-use change on climate. nature, 423(6939), 528-531. doi:10.1038/nature01675 matlhodi, b., kenabatho, p. k., parida, b. p., & maphanyane, j. g. (2019). evaluating land use and land cover change in the gaborone dam catchment, botswana, from 1984-2015 using gis and remote sensing. sustainability (switzerland), 11(19) doi:10.3390/su11195174 uddin, m. m. m. (2015). causal relationship between agriculture, industry and services sector for gdp growth in bangladesh: an econometric investigation. journal of poverty, investment and development, 8. mondal, i., srivastava, v. k., roy, p. s., & talukdar, g. (2014). using logit model to identify the drivers of landuse landcover change in the lower gangetic basin, india. paper presented at the international archives of the photogrammetry, remote sensing and spatial information sciences isprs archives, , xl-8(1) 853-859. doi:10.5194/isprsarchivesxl-8-853-2014 navale, v. b., & mhaske, s. y. (2019). land use/land cover changes in sangamner city by using remote sensing and gis. international journal of recent technology and engineering, 8(2), 4614-4621. doi:10.35940/ijrte.b3386.078219 nicolson, l.d. (1987). the greening of the cities; routledge and kegan paul, london nong, d., fox, j., miura, t., & saksena, s. (2015). built-up area change analysis in hanoi using support vector machine classification of landsat multi-temporal image stacks and population data. land, 4(4), 1213–1231. doi:10.3390/land4041213 park, h., fan, p., john, r., ouyang, z., & chen, j. (2019). spatiotemporal changes of informal settlements: ger districts in ulaanbaatar, mongolia. landscape and urban planning, 191 doi:10.1016/j.landurbplan.2019.103630 rajeshwari d. (2006). management of the urban environment using remote sensing and geographic information systems.j. hum. ecol., 20(4), 269-277. retrieved from http://www.krepublishers.com/02_journals/jhe/ md naimur rahman / geosi vol 4 no 3 (2019) 217-229 229 rasul, a., balzter, h., ibrahim, g., hameed, h., wheeler, j., adamu, b., … najmaddin, p. (2018). applying built-up and bare-soil indices from landsat 8 to cities in dry climates. land, 7(3), 81. doi:10.3390/land7030081 risma, zubair, h., & paharuddin. (2019). prediction of land use and land cover (lulc) changes using ca-markov model in mamuju subdistrict. journal of physics: conference series, 1341, 082033. doi:10.1088/1742-6596/1341/8/082033 schilling, k. e., jha, m. k., zhang, y.-k., gassman, p. w., & wolter, c. f. (2008). impact of land use and land cover change on the water balance of a large agricultural watershed: historical effects and future directions. water resources research, 44(7). doi:10.1029/2007wr006644 127 research article flash flood susceptibility mapping at andungbiru watershed, east java using ahp-information weighted method devi ratna handini, entin hidayah* , gusfan halik master program in civil engineering, department of civil engineering, faculty of engineering, university of jember, jl. kalimantan no. 37 jember, 68121, indonesia abstract flash floods are among the most frequent natural disasters caused by heavy rain associated with a severe thunderstorm, which leads to social and economic losses in infrastructure and agriculture. therefore, this research aims to map flash flood potential susceptibility (ffps) in the pekalen watershed, using geographic information system (gis) technology and statistical analysis to reduce the risk of flooding. the opinion and experience of an expert on the weight assessment method were carried out using the analytical hierarchy process (ahp). furthermore, the probability statistical methods and gis were used in flash flood areas in the pekalen watershed in andungbiru, probolinggo village. this study was carried out using geomorphological factors, namely elevation, slope, stream power index, and topographic wetness index, with a resolution of 30 m. thematic map scale of the land use, river density, distance to the river, rainfall, and geology is in the ratio of is in a ratio of 1:25,000. imagery processing was carried out using landsat 8 30 m x 30 m resolution imagery, such as the normalized difference vegetation index. the result showed that the model map of ffps obtained low 8%, low 23%, moderate 27%, moderate to high 26%, high 13%, and very high 2% index values. the next stage of modeling analysis led to validation using statistic receiver operating characteristic curve (roc) of area under curve (auc) with a value of 90.15. in conclusion, the factors that significantly trigger flash floods are distance to the river, land use, and slope. keywords: ahp-weighted; information content; ffsp; gis; geomorphology 1. introduction flash floods are one of the natural disasters affecting human life, leading to death and natural and artificial environmental damage (guzzetti et al., 2005; penning-rowsell et al., 2005; salvati et al., 2010). according to du et al. (2013), the process of measuring runoff areas and damage caused by flash floods is challenging. this is because flash flood disasters generally have varying intervals and durations (tehrany et al., 2015). *corresponding author. email address : entin.teknik@unej.ac.id (entin hidayah) geosfera indonesia vol. 6 no. 2, august 2021, 127-142 p-issn 2598-9723, e-issn 2614-8528 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v6i2. 24173 received 4 may 2021/ revised 1 june 2021/ accepted 15 june 2021/ published 17 august 2021 mailto:entin.teknik@unej.ac.id https://orcid.org/0000-0002-1233-6850 128 devi ratna handini et al. / geosfera indonesia 6 (2), 2021, 127-142 several research methods use ahp as a disaster modeling map extension. ahp is also used to calculate weight assessment based on the opinion and experience of experts (bui et al., 2019; elkhrachy, 2015; he et al., 2019). the research on potential mapping disasters using opinions and combination statistics produced good validation values, namely ahpweighted information content auc 0.893, ahp method 0.821, and information content 0.842 (he et al., 2019). this study used the ahp-weighted information content method, which combines the expert experience method and frequency distribution statistics. the model results are validated using statistics, while the area below the curve (auc) is used to calculate the accuracy of the flash flood model. mapping potential flash flood-prone areas using the ahp-weighted information content method is essential for sustainable planning (costache et al., 2020), protecting life, and maintaining a river condition environment (zhang et al., 2015). ahp is a method used for various kinds of disasters, such as landslides, flash floods, etc. this is an interesting research due to its complex nature, making it possible to carry out a spatial approach during the flash flood modeling process (he et al., 2019). there has never been a mapping of the potential for flash floods in the pekalen watershed, therefore, it is imperative to use the ahp method combined with information content weights to determine the factors that influence the accuracy of the modeling results. vulnerability is needed to determine the appropriate methods and analysis needed to map a potential flash flood (cloke & pappenberger, 2009). flash flood modeling utilizes gis mapping and remote sensing methods (pradhan & shafie, 2009). the purpose of this study is to apply the ahp-weighted information content method at in the pekalen watershed using a geographic information system (gis). this method was used to determine the distribution of potential flash flood events based on factors that have been calculated from their various weights using expert knowledge and mathematical analysis. 2. methods 2.1 study area this research was carried out in pekalen watershed, probolinggo, east java, with coordinates 1130.23 e-1130.35 e and 70.55'0 80.2'3. figure 1 shows the flash flood event area is in the village, with the area of the upper pekalen watershed covering 8,530 hectares. the flash flood event occurred at an elevation of 608 meters above sea level. 129 devi ratna handini et al. / geosfera indonesia 6 (2), 2021, 127-142 figure 1. the study area 2.2 research design the predetermined parameters used to determine flash floods are elevation, slope, spi, twi, land use, river density, distance to river, ndvi, short-term heavy rain, and geology. these parameters are essential because each region has different regional morphological characteristics (elkhrachy, 2015). data were collected from the inventory of flash flood events obtained from the survey at the site. the results consist of 70% training data (63 ha) and 30% validation (27 ha) (kia et al., 2012). the selection of factors mapping the potential of flash floods is essential in creating an insecurity map to determine the elevation, slope, twi (costache et al., 2020), spi, river density, rainfall, ndvi (bui et al., 2019), land use (costache et al., 2020), geology (cao et al., 2016), and distance from the river (popa et al., 2019). table 1 is a general description of data source and resolution information. table 1. factors used in flash flood mapping modeling flash flood factor source resolution elevation www.usgs.gov (usgs, 2020) 30 x 30 m slope derivated from srtm (nasa, 2020) 30 x 30 m spi derivated from srtm (nasa, 2020) 30 x 30 m twi derivated from srtm (nasa, 2020) 30 x 30 m land use tanahair.indonesia.go.id (big, 1999) 1 : 25,000 river density derivated from layer of river 30 x 30 m distance to river derivated from layer of river 30 x 30 m ndvi landsat 8 (usgs, 2020) 30 x 30 m rainfall derivated from layer of rainfall 30 x 30 m geology tanahair.indonesia.go.id (big, 1999) 1:25,000 http://www.usgs.gov/ 130 devi ratna handini et al. / geosfera indonesia 6 (2), 2021, 127-142 furthermore, this study comprises geomorphological and hydrological factors, with figures 2-11 showing the classification of each factor. the spatial data types are grid and vector layers. figure 2. slope map figure 3. elevation map figure 4. stream power index map figure 5. topographic wetness index map figure 6. river density map figure 7. distance to river map 131 devi ratna handini et al. / geosfera indonesia 6 (2), 2021, 127-142 figure 8. ndvi map figure 9. rainfall map figure 10. geology map figure 11. land use map a. the slope (degree) (figure 2) factor is derivated from the elevation data and marbles, which significantly influence the process of flow (khosravi et al., 2016). b. elevation (meter) (figure 3) data is obtained from nasa imagery with srtm radar resolution of 30 x 30 (m). in general, flash floods usually occur in areas with plateaus. c. topographic wetness index (twi) and stream power index (spi) imagery (figures 4 and 5) are derived from dem factors considered as variables that describe the hydrological arrangement of an area. in general, a high twi value indicates the presence of prone areas with wet topography and potential to surface runoff. similarly, spi is a topographic prediction used to model the strength of a water flow. the topographic wetness index (twi) is a spatial concept that models the accumulation of flow from each basin and the ability of water to move due to its slope and gravity. spi and twi modeling is derived from dem and processed using tools in saga gis, along with similarities from twi (eq.1) and spi (eq. 2) modeling (moore et al., 1991). 132 devi ratna handini et al. / geosfera indonesia 6 (2), 2021, 127-142 twi= 𝐿𝑛 ( 𝐴𝑠 𝛽 ) = 𝐿𝑛 ( 𝐴𝑠 𝛽 ) ......................................................................................... (1) spi= 𝐴𝑠𝑥 tan 𝛽 = 𝐴𝑠𝑥 tan 𝛽 ................................................................................... (2) where the as and β denote specific water catchment areas (m2/m) and slope angles in degrees. twi shows the amount of flow accumulated at any point in the catchment area and the tendency of water to descend to the slope using gravitational force (moore et al., 1991). d. an ndvi (ratio) is a measure that describes the vegetation characteristics of an area, factors that affect the surface flow, and the infiltration capabilities of a site (figure 8). according to tehrany et al. (2013), areas with less dense vegetation are considered more prone to flooding. e. distance to the river (meter) is a factor that is lower from the thematic map layer of the river (figure 7). this is a factor that shows the distribution of flash flood events to the position of the river (popa et al., 2019). f. the river density (km/m) that flows in watersheds influences the level and intensity of flash floods (figure 6). the river network and the surrounding areas are highly vulnerable to the manifestation of flash flood events (fernández & lutz, 2010). g. the geology map (figure 10) obtained from rupa bumi indonesia (rbi) is one of the factors contributing to the response to water flow when there is high rain (cao et al., 2016). h. rainfall (mm) is also considered an essential variable in the assessment of flash flood vulnerability (figure 9). therefore, precipitation is used to produce a map of rainfall distribution using the inverse distance weighted (idw) method (bartier & keller, 1996). figure 12. flow chart of the methodology 133 devi ratna handini et al. / geosfera indonesia 6 (2), 2021, 127-142 2.3 ahp-weighted information content method ahp-weighted information content method is a technique that combines expert monitoring and statistical calculation. the calculated value is entered into the class of each factor, while the weight is obtained from used distribution frequency formulas implemented into gis. eq. 3 is a formula for determining each class. 𝐼(𝑋𝑖, 𝐻) = 𝑙𝑛 𝑁𝑖 /𝑁 𝑆𝑖 /𝑆 𝐼(𝑋𝑖 , 𝐻) = 𝑙𝑛 𝑁𝑖 /𝑁 𝑆𝑖 /𝑆 ..................................................................................(3) where s is the area of study, n is the total area of flash floods, si is the number of disaster-causing factors, and ni is the number of flash floods distributed in the causative factors of the disaster. ahp weight assessment is calculated based on the opinion of experts, while the probability statistic model is used to determine the weight of each factor class. ffsp is calculated using the eq. 4 (he et al., 2019). 𝐹𝐹 = 𝛽1𝐺1 + 𝛽2𝐺2 + 𝛽3𝐺3 + 𝛽4𝐺4 + 𝛽5𝐺5 + 𝛽6𝐺6 + 𝛽7𝐺7 + 𝛽8𝐺8 + 𝛽9𝐺9 + 𝛽10𝐺10𝐹𝐹 = 𝛽1𝐺1 + 𝛽2𝐺2 + 𝛽3𝐺3 + 𝛽4𝐺4 + 𝛽5𝐺5 + 𝛽6𝐺6 + 𝛽7𝐺7 + 𝛽8𝐺8 + 𝛽9𝐺9 + 𝛽10𝐺10 .................................................................................................................(4) eq. 2 is the sum of the weight of each class for each factor. this summation produces a flash flood potential layer next in the process of re-class in gis to determine the index of potential flash floods (he et al., 2019). ahp-weighted information content method is used to develop the ahp method by combining it with the statistic probability of frequency distribution. the assessment process provides constant value on each factor and frequency distribution assessment to give weight to each class. furthermore, the calculated value is converted into a gis layer, then to t he numeric form and spatial data. after each factor is converted, their sum is weighed to create a potential flash flood map before proceeding to the reclassification stage to create an index class. according to khosravi et al. (2016), the selection of index class for the map of ffsp used the trusted natural breaks method because it is most suitable for the classification process of index map insecurity. validation is a critical stage in creating and identifying maps of areas vulnerable to flash floods and determining the model's quality. therefore, the modeling results are unusable, assuming they do not have validation values (biswajeet pradhan & lee, 2010). roc is a method widely used to evaluate the accuracy level of model results. tehrany et al. (2013) stated that using this method is better because the results are generally complete with good visuals. many studies use this method as an option for their validation process (5). 134 devi ratna handini et al. / geosfera indonesia 6 (2), 2021, 127-142 furthermore, in the potential mapping of flash flood disasters, the prediction model results need to be evaluated in the modeling process. this study uses the statistical analysis method to quantitatively calculate the relationship between flash floods and causal factors based on a spatial modeling approach. it also focuses on the probability of frequency distribution with the approach of geodynamic environmental data. the method combines probability data with the opinions of experts that need to be verified. 3. results and discussion calculating ahp results using weighted information content determined the weight value of each class factor. ahp is a method that uses expert opinion, such as individuals that are professionals in the field of disaster and gis, to determine the input from the weight of each factor. the opinions of these experts include the national disaster relief agency, national disaster management authority, hydrologists, gis experts, and the development planning agency at sub-national level. figure 13 is the result of an ahp weighted information content calculation. figure 13. ahp-weighted information content calculation results in figure 13, the weight calculation shows that the factor with the most significant negative value is the distance to river factor, which is in the second class with a weight value of -5.42. this is followed by the land-use and marble factors with negative values -3.22 and 2.70. the ahp-weighted information content calculation results consist of positive and negative values. the positive values indicate that the probability of events is more significant in each class than in the factor class. 135 devi ratna handini et al. / geosfera indonesia 6 (2), 2021, 127-142 algorithm natural (ln) formula produces both negative and positive values. the negative value indicates that the probability of events is less than the value of a factor class. the factor with the highest positive value, namely the land-use in the rice field feature, has a value of 3.69, followed by the rainfall factor in the sixth grade worth 2.73 and the fifth rate at 1.49. in the class of marbles, the positive score is first class with a value of 1.30, which ranges from zero to seven degrees. the case at the research site based on the probability of events and factors used in this study stated that flash floods occurred at a reasonably high elevation of 475-621 m, at a slope of 0-7 and 17-21 degrees. the incident occurred in rice fields using settlements and fields with river runoff up to 177 m during the 15 mm continuous rainfall. the gis software is used to determine the overlay of each factor. the natural interval statistical method is used to determine the classification results, consisting of six classes, namely low, low, medium, medium to high, high, and very high. the following figures (figure 14 figure 23) illustrate the weighting in each class. figure 14. elevation (m) figure 15. slope (degree) in the elevation factor (figure 14), the probability value of events in the first class with a value of one ranges from 475 – 621 m. meanwhile, in the slope factor (figure 15), the probability of the highest occurrence in the first, second, third, and fourth classes are 1.30, 0.36,-0.1 and -2.70. 136 devi ratna handini et al. / geosfera indonesia 6 (2), 2021, 127-142 figure 16. stream power index figure 17. topographic wetness index in the spi factor (figure 16), the probability value of events in class one has a value of 0.01 with a range of spi 0-324 and -0.37 in class two. in the twi factor (figure 17), the probability value of its appearance in classes one, two, three, four, five, and six are -1.31, 0.87, -0.01, 0.56, 0.80, and 1.38. figure 18. land use figure 19. river density (km/m) on the land use factor (figure 18), the value of the probability of forest occurrence is 0.00 for plantations at 1.44. the highest negative value for land use is -3.22 and -199 for settlements, while the highest for rice fields is 3.69 and -1.90 for shrubs. for the river density factor (figure 19), the value of the probability of occurrence in classes one, two, three, four, five, and six are 0, -1.38, 1.10, -0.87, 0.07, and -0.75. 137 devi ratna handini et al. / geosfera indonesia 6 (2), 2021, 127-142 figure 20. distance to the river (m) figure 21. ndvi (ratio) the distance factor to the river (figure 20) and the probability value in class one and are 0.95 and -5.42. meanwhile, in classes three, four, five, and six, it is 0.00. in the ndvi factor (figure 21), the probability event value in classes one, two, three, four, five and six are 1.27, 0.74, 0.74, -0.23, -0.58, and -0.78. figure 22. rainfall (mm) figure 23. geology in the rainfall factor (figure 22), the probability event value in grades one, two, three, and four have a score of 0.00. meanwhile, in the fifth and sixth grades, the scores are 1.49 and 2.73, respectively. in the geology factor (figure 23), the probability event value in argopuro volcanic and lamong volcanic rock are 0.23 and 0.00. the class weight value of each layer factor needs to be converted into data with a grid resolution of 30 m x 30 m using the gis. the results of the map of potential flash floods are shown in figure 24. 138 devi ratna handini et al. / geosfera indonesia 6 (2), 2021, 127-142 figure 24. map of potential flash floods table 3. table of percentage and broad proportional values on models in each class class count area (m 2 ) percentage (%) very low 7748 697.32 8 low 21577 1941.93 23 moderate 25545 2299.05 27 moderate to high 24574 2211.66 26 high 11729 1055.61 13 very high 2268 204.12 2 the calculation obtained a map of the spread of flash flood insecurity with each index class, as shown in figure 24. the study area in table 3 shows that the highest percentage value is moderate 27%, followed by moderate to high 26%, low 23%, high 13%, very low 8%, and very high with only 2%. the spatial distribution shows that the research area is fairly vulnerable because moderate to high values dominate 27% and 26%, respectively. the results of the flash flood encoding using the ahp method can carry out the validation process using the graph below the auc curve, as shown in figure 25. 139 devi ratna handini et al. / geosfera indonesia 6 (2), 2021, 127-142 figure 25. receiver operating characteristic (roc)-based analysis of the area under the curve (auc) data graph the advantage of this research is to test the performance model that uses a combination of statistics and expert statements, with the results of a map and the distr ibution of potential flood events. this research utilized factors that have been used in previous studies related to flash flood disasters in the pekalen watershed, such as elevation (bui et al., 2019; costache et al., 2020), slope (khosravi et al., 2016), twi (bui et al., 2019), spi (bui et al., 2019), land use (costache et al., 2020), distance to the river (popa et al., 2019), river density (bui et al., 2019), ndvi (bui et al., 2019), rainfall (bui et al., 2019), geology (cao et al., 2016). previous studies used various approaches to determine geomorphologica l factors; therefore, the most frequently used factors for modeling were implemented in this study. the statistic method for the validation process used the analysis method under the curve (auc) to obtain an event model value of 90.15%, as shown in figure 25. this value indicates that the modeling made based on the probability of frequency distribution has proximity between flash flood events models. in addition, the increase in performance (auc value) is supported by a selection factor that is adjusted to the type of flash flood events from similar studies, which have an auc value above 80%. the resulting flood hazard map is 30 m x 30 m resolution at a scale of 1:25,000. this map can be used as a reference in making flood risk models and regional spatial alignment, therefore, they are able to offer risk. 0 10 20 30 40 50 60 70 80 90 100 0 20 40 60 80 100 t r u e p o si ti v e r a te ( se n si ti v ty ) auc ahp weighted information content 140 devi ratna handini et al. / geosfera indonesia 6 (2), 2021, 127-142 4. conclusion in conclusion, the flash flood potential vulnerability map using the ahp-weighted information content method gives a significant result. furthermore, adjusting the resulting map of each layer produced a resolution of 30 m x 30 m on a scale of 1:25,000. of the ten factors analyzed using ahp-weighted information content, those that significantly trigger flash floods are distance to the river, land use, and slope with a weight value of four. this shows the area with a high probability of occurring in the rice field features. meanwhile, factors that have weak influence are twi, spi, and land-use factors. in this study, land use has a high value because it is a factor that affects runoff on the surface. the flash flood susceptibility potential map can be used as a reference in flood mitigation, with a resolution scale of 30 m x 30 m. furthermore, research on modeling, it required information on the previous occurrence to determine the temporal phenomena that occur. the group number of each factor needs to be varied to test the dominance of the triggering factors for a flash flood. conflict of interest the authors declare no conflict of interest. references bartier, p. m., & keller, c. p. (1996). multivariate interpolation to incorporate thematic surface data using inverse distance weighting (idw). computers and geosciences, 22(7), 795–799. https://doi.org/10.1016/0098-3004(96)00021-0. big (1999). peta rbi format shp. retrieved from https://tanahair.indonesia.go.id/portalweb. bui, d. t., tsangaratos, p., ngo, p. t. t., pham, t. d., & pham, b. t. (2019). flash flood susceptibility modeling using an optimized fuzzy rule based feature selection technique and tree based ensemble methods. science of the total environment, 668, 1038–1054. https://doi.org/10.1016/j.scitotenv.2019.02.422. cao, c., xu, p., wang, y., chen, j., zheng, l., & niu, c. (2016). flash flood hazard susceptibility mapping using frequency ratio and statistical index methods in coalmine subsidence areas. sustainability (switzerland), 8(9). https://doi.org/10.3390/su8090948. cloke, h. l., & pappenberger, f. (2009). ensemble flood forecasting: a review. journal of hydrology, 375(3–4), 613–626. https://doi.org/10.1016/j.jhydrol.2009.06.005. costache, r., pham, q. b., sharifi, e., linh, n. t. t., abba, s. i., vojtek, m., vojteková, j., nhi, p. t. t., & khoi, d. n. (2020). flash-flood susceptibility assessment using multicriteria decision making and machine learning supported by remote sensing and gis techniques. remote sensing, 12(1). https://doi.org/10.3390/rs12010106. 141 devi ratna handini et al. / geosfera indonesia 6 (2), 2021, 127-142 du, j., fang, j., xu, w., & shi, p. (2013). analysis of dry/wet conditions using the standardized precipitation index and its potential usefulness for drought/flood monitoring in hunan province, china. stochastic environmental research and risk assessment,27(2), 377–387. https://doi.org/10.1007/s00477-012-0589-6. elkhrachy, i. (2015). flash flood hazard mapping using satellite images and gis tools: a case study of najran city, kingdom of saudi arabia (ksa). egyptian journal of remote sensing and space science, 18(2), 261–278. https://doi.org/10.1016/j.ejrs.2015.06.007. fernández, d. s., & lutz, m. a. (2010). urban flood hazard zoning in tucumán province, argentina, using gis and multicriteria decision analysis. engineering geology, 111(1– 4), 90–98. https://doi.org/10.1016/j.enggeo.2009.12.006. moore, i. d., grayson, r. b., & ladson, a. r. (1991). digital terrain modeling: a review of hydrological, geomorphological, and biological applications. hydrological processes, 5(1), 3–30. https://doi.org/10.1002/hyp.3360050103. nasa (2020). shuttle radar topography mission (srtm). retrieved from https://cmr.earthdata.nasa.gov/search/concepts/c1000000240-lpdaac_ecs.html. guzzetti, f., stark, c. p., & salvati, p. (2005). evaluation of flood and landslide risk to the population of italy. environmental management, 36(1), 15–36. https://doi.org/10.1007/s00267-003-0257-1. he, h., hu, d., sun, q., zhu, l., & liu, y. (2019). a landslide susceptibility assessment method based on gis technology and an ahp-weighted information content method: a case study of southern anhui, china. isprs international journal of geo-information, 8(6). https://doi.org/10.3390/ijgi8060266. khosravi, k., nohani, e., maroufinia, e., & pourghasemi, h. r. (2016). a gis-based flood susceptibility assessment and its mapping in iran: a comparison between frequency ratio and weights-of-evidence bivariate statistical models with multi-criteria decision-making technique. natural hazards, 83(2), 947–987. https://doi.org/10.1007/s11069-016-23572. kia, m. b., pirasteh, s., pradhan, b., mahmud, a. r., sulaiman, w. n. a., & moradi, a. (2012). an artificial neural network model for flood simulation using gis: johor river basin, malaysia. environmental earth sciences, 67(1), 251–264. https://doi.org/10.1007/s12665-011-1504-z. penning-rowsell, e., floyd, p., ramsbottom, d., & surendran, s. (2005). estimating injury and loss of life in floods: a deterministic framework. natural hazards, 36(1–2), 43–64. https://doi.org/10.1007/s11069-004-4538-7. popa, m. c., peptenatu, d., draghici, c. c., & diaconu, d. c. (2019). flood hazard mapping using the flood and flash-flood potential index in the buzau river catchment, romania. water (switzerland), 11(10). https://doi.org/10.3390/w11102116. pradhan, b, & shafie, m. (2009). flood hazard assessment for cloud prone rainy areas in a typical tropical environment. disaster advances, february. https://cmr.earthdata.nasa.gov/search/concepts/c1000000240-lpdaac_ecs.html 142 devi ratna handini et al. / geosfera indonesia 6 (2), 2021, 127-142 pradhan, biswajeet, & lee, s. (2010). delineation of landslide hazard areas on penang island, malaysia, by using frequency ratio, logistic regression, and artificial neural network models. environmental earth sciences, 60(5), 1037–1054. https://doi.org/10.1007/s12665-009-0245-8. salvati, p., bianchi, c., rossi, m., & guzzetti, f. (2010). societal landslide and flood risk in italy. natural hazards and earth system science, 10(3), 465–483. https://doi.org/10.5194/nhess-10-465-2010. tehrany, m. s., pradhan, b., & jebur, m. n. (2013). spatial prediction of flood susceptible areas using rule based decision tree (dt) and a novel ensemble bivariate and multivariate statistical models in gis. journal of hydrology, 504, 69–79. https://doi.org/10.1016/j.jhydrol.2013.09.034. tehrany, m. s., pradhan, b., & jebur, m. n. (2015). flood susceptibility analysis and its verification using a novel ensemble support vector machine and frequency ratio method. stochastic environmental research and risk assessment, 29(4), 1149–1165. https://doi.org/10.1007/s00477-015-1021-9. usgs (2020). landsat 8 imagery. retrieved from https://www.usgs.gov/. zhang, d. wei, quan, j., zhang, h. bin, wang, f., wang, h., & he, x. yan. (2015). flash flood hazard mapping: a pilot case study in xiapu river basin, china. water science and engineering, 8(3), 195–204. https://doi.org/10.1016/j.wse.2015.05.002. https://www.usgs.gov/ impact of infrastructure development jalur jalan lintas selatan (jjls) on changes in land use in gadingsari village, sanden district, bantul regency, yogyakarta, indonesia hendry edy 1), m. baiquni 2), bambang triatmodjo 3) 1doctoral student in environmental sciences doctoral study program postgraduate school of universitas gadjah mada 2lecturer in doctoral program in environmental sciences postgraduate school of universitas gadjah mada and lecturer in regional development study program at the faculty of geography, universitas gadjah mada 3lecturer in doctoral program in environmental sciences postgraduate school of universitas gadjah mada and lecturer in civil engineering study program, faculty of engineering, universitas gadjah mada email: 1hendry_edy@yahoo.com, 2baiquni99@gmail.com, 2bambang.tsipil@yahoo.co.id received 23 march 2019/ revised 22 july 2019/ accepted 24 july 2019/ published 1 august 2019 abstract infrastructure development jalur jalan lintas selatan (jjls) is a national program that passes through 5 provinces in java, which is one of the provinces passed through the special region of yogyakarta. one of the villages passed by the jjls development in the special province of yogyakarta is gadingsari village, sanden district, bantul regency. in this study, it will be seen how changes in land use in gadingsari village before and after jjls. the purpose of this study was to analyze changes in land use that occurred in gadingsari village. the analytical method used is a qualitative descriptive analysis method. changes in land use were obtained from the satellite image overlay analysis in the span of time, namely before jjls was built in 2013 and after jjls was built in 2017 and strengthened with field surveys and in-depth interviews. from the results of the research, it was found that the land area for settlements in gadingsari village before and after the jjls had changed. before the existence of jjls residential area was 78.90 hectare and it expanded to 104.93 hectare after the construction of jjls, there was an increase of around 32.99% . key words: infrastructure, overlay, jjls, land 1. introduction java island belongs to the group of developing regions in its good economic growth, generally located along the northern coast of java island such as semarang, pati, rembang and jepara. the opposite condition occurs in the southern part of the island of java where geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.4 no. 2 (2019), 78-89, august, 2019 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v4i2.10014 78 hendry edy, et al/ geosi vol. 4 no. 2 (2019) 78-89 economic growth is slow and there is not much activity and movement of people or goods that occur. this happens because the road infrastructure is on the north coast where the code is good so the traffic is very heavy. in addition, when viewed from a landscape perspective the north coast is a lowland with many deltas, while the south coast coastal area is dominated by steep and thick beaches interspersed with sandy beaches. geographically, the south coast region of java consists of karts mountains and the condition of the region is dry.this condition creates a gap between regions, namely between the northern region and the southern region of java. the southern part of the island of java actually has great economic potential including fertile land, mining resources, marine resources, coastal tourism, karst cave tourism, natural and mountain tourism, forest tourism and cultural tourism (historical and cultural heritage) . these potentials have not been worked out well due to the limited infrastructure available on the south coast of java. to overcome these problems, infrastructure development is needed that can support the development of existing potentials. the availability of infrastructure can have an influence on increasing people's access to resources, thereby increasing access to productivity of resources which ultimately drives economic growth.the construction of roads in an area will open access to the area with other regions so that the flow of vehicles, goods or products can be transported quickly. with the existence of this road, there will be a lot of community efforts in order to fulfill the necessities of life such as opening stalls, restaurants or other businesses which will then move the economy of the local community. if the community along jjls cannot take advantage of this opportunity, investors will take over to take advantage of this opportunity. one of the infrastructure that is needed in this case is the road infrastructure. roads are the driving factor for economic change, regions that have a lot of road access tend to encourage land change in a direction that cannot be reversed (kubangun et al, 2016). road is one of the most important infrastructures to support economic activities to overcome the gap in the northern part of java and the southern part of java. in this southern part of java, the government built the jalur jalan lintas selatan (jjls). road is one of the most important infrastructures to support economic activities to overcome the gap in the northern part of java and the southern part of java. in this southern part of java, the government built the southern cross road (jjls). the construction of the jalur jalan lintas selatan (jjls) is one of the government's efforts through the ministry of public works to increase the availability of infrastructure in the southern part of java. the southern crossroad road was built to reduce the density of transportation on the north java coast (pantura) and to spur the development of the region in the south java region. in addition, the construction of the jalur jalan lintas selatan (jjls) is 79 hendry edy, et al/ geosi vol. 4 no. 2 (2019) 78-89 also expected to increase access to mobility so that it can encourage economic growth in the areas traveled by jjls. the jalur jalan lintas selatan (jjls) will connect 5 provinces in java, namely banten, west java, central java, yogyakarta and east java. the implementation of infrastructure development especially roads is expected to provide a variety of positive impacts on the community. the construction of the southern cross roadway is expected to be able to provide various implications for the surrounding communities. in principle, every implementation of development will always be an interaction or conflict of interest between the components of activities and environmental components so that it will cause changes in the environment. the land affected by jjls construction in gadingsari village is the sultan ground which belongs to the sultanate of yogyakarta. although its ownership is the sultanate of yogyakarta, the yogyakarta sultanate gives the opportunity to the community to manage and utilize the land for the benefit of the community. regulations that must be obeyed by the community are not allowed to build permanent buildings on the sultan ground land, so that there are no permanent buildings along jjls in gadingsari village.road construction will be able to exert influence on the area it passes through, both social, economic and other impacts. plans for the construction of the java southern cross road network of the special province of yogyakarta are carried out through 3 (three) stages of work, namely short-term, mid-term and long-term programs. in further developments the short-term program (20052007) connected between congot (central java province boundary) srandakan poncosari kretek parangtritis girijati klampok planjan baron duwet (central java province boundary) along 130, 305 kilometers by utilizing existing roads through widening the road to 7 m. the long-term program (2008-2025) connects between congot (central java provincial boundary) srandakan kretek parangtritis baron-duwet (central java province boundary) along 117.60 kilometers with a road body of 24 m (2 x 7 m asphalt ), make roads and bridges and tunnels. especially for tunnel construction, it is still in the discourse so that it is not included in the amdal study study. the target for the construction of the southern cross road in the special region of yogyakarta is divided into 2 programs, namely short-term programs and long-term programs. the short term program is basically to connect the road network across the southern island of java by utilizing the existing road network. while the long-term program is the construction of a long-term road and bridge network not entirely through network routes in short-term programs due to several technical matters and other considerations. the route used in the long-term program in the bantul regency area has a slight shift in the route with a road 80 hendry edy, et al/ geosi vol. 4 no. 2 (2019) 78-89 length of 6.82 kilometers (dirt road) connecting through the srandakan iii bridge, the total length for the segment congot-srandakan is 25.65 kilometers. the route from srandakanprangtritis passes an existing road network with a segment length of 23.40 kilometers. the route from srandakan parangtritis passes an existing road network with a segment length of 23.40 kilometers. parangtritis route baron is still awaiting the results of further studies to determine the final route (there is a separate study of the possibility of making tunnels) baron route duwet uses an existing route in accordance with the route developed for short-term programs. the length of this route is 41.09 kilometers. one of the villages passed by the construction of the jalur jalan lintas selatan (jjls) is gadingsari village, located in sanden district, bantul regency, special region of yogyakarta. the construction of the road in gadingsari village began in 2013. road construction was carried out by widening the existing roadway. after the completion of the construction of the jalur jalan lintas selatan (jjls) in gadingsari village, land use changes occurred, especially the increase in land used for settlements. the purpose of this study is to find out changes in land use that occurred in gadingsari village before the construction of the jalur jalan lintas selatan (jjls) in 2013 and after the existence of the jalur jalan lintas selatan (jjls) in 2017. the construction of jjls is expected to support economic activities and will tackling the gap in the northern part of java and the southern part of java. in this study we will look at the impact of jjls development on changes in land use. most of the land before the construction of jjls was land in the form of moor, gardens or rainfed rice fields which would be transformed into residential land. 2. the methods gadingsari village is located in sanden subdistrict, bantul regency with an area of 811.74 hectares with regional boundaries as follows: north side: caturharjo village, pandak district south side: indonesian ocean west side: poncosari village, srandakan district east: murtigading and gadingharjo village, sanden district the research location is gadingsari village, sanden district, bantul regency can be seen in figure 1. 81 hendry edy, et al/ geosi vol. 4 no. 2 (2019) 78-89 figure 1. map of research location in gadingsari village in this study the tool used is a computer (hardware) that is used to digitize maps, software (gis software) to process spatial data: arcgis 10.2 and google earth take digital images and gps (global positioning system) used in fieldwork to shows the position so that it matches the predetermined point. the material used in this study is the map of sindutan village administration, maps of sindutan village land use in 2013 and 2017 sourced from existing images on google earth, secondary data of sindutan village monograph and other data related to research. data collection techniques in this study are documentation, image interpretation, observation and in-depth interviews. as the primary data in this study are the images obtained from google earth sindutan village, sanden subdistrict, bantul regency in 2013 and 2017. the primary data in this study is satellite imagery for the sindutan village area. furthermore, for secondary data can be obtained directly through the agency government agency at the research location. imagery can be interpreted as a visible picture of an object being observed, as a result of coverage or recording of a monitoring device / sensor, both optical, electro optical, optical-mechanical, or electromagnetic (kusumaningrat et al, 2017). image requires a process of interpretation or interpretation in advance in its use. in this research, image interpretation is done using the arcgis 10.2 program. in the form of visual interpretation, by interpreting or digitizing images to separate certain objects to produce a 82 hendry edy, et al/ geosi vol. 4 no. 2 (2019) 78-89 map of land use change. based on image interpretation, it can be seen land use, and area of use in each year of shooting, so that from this interpretation results obtained two tentative maps of land use (in 2013 and 2017). the results of this interpretation are tentative and incomplete maps. this tentative map so that it becomes a complete map and has a high level of trust, it is necessary to do a field check (observation). observation is a way to collect research data through observation, recording, and visiting agencies to get the data needed. from the observation activities data can be obtained that may not be obtained from the image so that the map of the interpretation results can be corrected according to the latest data and can become the actual map. during this observation, in-depth interviews were also conducted. the purpose of the interview was to look at land use in the research area when conducting field checks. is the condition appropriate or not in accordance with the appearance shown in the image. interviews were conducted with residents around the land use and knowing the history of the land use. the data analysis technique in this study was carried out by analysis of the geographic information system. analysis of changes in land use by utilizing temporal spatial data is very useful, especially to find out the locations where changes in land use occur (nuraeni, et al, 2017). in this study data was obtained from the results of image interpretation analyzed, namely the 2013 land use map and 2017, then the data was analyzed. the analysis at this stage is the reinterpretation (reinterpretation) of the map done after testing the accuracy and observation. from the reinterpretation process, an overlayed land use change map will be produced (data for 2013 and 2017). analysis of changes in land use, area of each land use, extent of change, with analysis of geographic information systems. each of the different land use maps is stacked with the overlay technique, so that changes in type, area, and area of land change can be identified to produce information in the form of land use change maps in sindutan village, sanden district, bantul regency. after doing the geographic information system (gis) analysis technique with the overlay technique then qualitative descriptive analysis techniques were carried out. descriptive analysis is used to explain the findings in the field. the findings of the study included extensive changes in land use and types of land use. 3. results and discussion the land use map is taken from the imagery that is on google earth temporal, then a visual interpretation of each temporal is carried out with the arcgis 10.2 program. from the 83 hendry edy, et al/ geosi vol. 4 no. 2 (2019) 78-89 results of the land use map analysis in 2013 which can be seen on the land use map in gadingsari village in figure 2 and the area for each land use in table 1. the lake area is 0.50 hectares, bushes of 3.39 hectares, for gardens covering 281.73 acres of settlement covering 78.9 hectares, irrigated rice fields covering 226.09 hectares, moorlands covering 94.59 hectares, land sand covering an area of 78.72 hectares and grass area of 6.05 hectares. table 1. table of 2013 land use maps no land use large (hectares) 1. lake 0,50 2. bushes 3,39 3. garden 281,73 4. settlement 78,90 5. irrigated rice fields 226,09 6. moorings 94,59 7. land sand 78,72 8 grasses 6,05 source: interpretation of google earth images 2013 figure 2. map of land use in gadingsari village in 2013 whereas the land use of gadingsari village in 2017 can be seen on the land use map in figure 3 and the area of each land use can be seen in table 2. lake area is 0.50 hectares, bushes are 3.39 hectares, for gardens covering 259.95 hectares, settlement 104.93 hectares, irrigated rice 84 hendry edy, et al/ geosi vol. 4 no. 2 (2019) 78-89 fields covering 226.09 hectares, moorlands covering 94.59 hectares, land sand covering an area of 75.74 hectares and grasses covering an area of 6.05 hectares. table 2. table of 2017 land use maps source: interpretation of google earth images 2017 figure 3. map of gadingsari village land use in 2017 changes in land use in 2013 to 2017 can be seen in figure 4. the extent of land use change that occurred from 2013 before the jjls and in 2017 after the jjls can be seen in table 3. no land use luas ( hectares ) 1. lake 0,50 2. bushes 3,39 3. garden 259,95 4. settlement 104,93 5. irrigated rice fields 226,09 6. moorings 93,32 7. land sand 75,74 8. grasses 6,05 85 hendry edy, et al/ geosi vol. 4 no. 2 (2019) 78-89 the change in garden land into a settlement of 21.78 hectares, changes the dry land is a settlement of 1.27 hectares while the land sand is a residential area of 2.98 hectares. table 3. table of changes in land use in 2013 to 2017 source: interpretation of google earth images 2013-2017 figure 4. map of changes in land use of gadingsari village from 2013 to 2017 in the study of land use change in gadingsari village, land use changes occurred before the south cross road (jjls) occurred in 2013 and after the existence of jjls in 2017. changes in land use that occurred on agricultural land turned into residential land and land no land use large (hectares) change (hectares ) 2013 2017 increase reduced 1. lake 0,50 0,50 2. bushes 3,39 3,39 3. garden 281,73 259,95 21,78 4. settlement 78,90 104,93 26,03 5. irrigated rice fields 226,09 226,09 6. moorings 94,59 93,32 1,27 7. land sand 78,72 75,74 2,98 8. grasses 6,05 6,05 86 hendry edy, et al/ geosi vol. 4 no. 2 (2019) 78-89 changes. the road along the jjls gadingsari village found many flower gardens that were deliberately made by the surrounding community. these botanical gardens are tourist attractions for tourists, tourists can take pictures in the park with payment of retribution, so that this retribution can provide information for people who manage the land around jjls gadingsari village. there are several other studies related to changes in land use. fadilla restu et al, 2018 agreed on the conformity analysis of changes in land use to spatial / regional plans in the districts of penjaringan, north jakarta administration, using geographic information systems. this study discusses the suitability of the plan with the existing conditions in the field with mapping. this study focuses more on 2013 land use suitability for the jakarta spatial planning (rtrw) in 2030. ahardi m. ardhi et al .'s research in 2015 on the effect of changes in land use on changes in land value zones in gayamsari sub-district, semarang city in 2004 and 2014. the results of this study indicate the total area of land use change in gayamsari subdistrict in 2004 to 2014 was 106 ha. the biggest change in land use occurs in the use of dry land into settlements with an area of 24 ha. beatus m. laka et al., 2017 examined the changes in land use in sirimau district, ambon city. based on the results of the study it was concluded that the change in the area of land use in sirimau district, ambon city, in the last 10 years was very large for settlements of 1036.1 ha from the previous year amounting to 966.9 ha.another researcher who examined the related changes in land use was sadewo m nur et al, 2018 which examined simulation of changes in land use due to cellular automata-based kendal industrial estate (kik) development. based on the results of the research that has been done, it can be concluded that the cellular automata model is able to predict land use in 2031 in east kendal with the influence of kik development with a model accuracy rate of 95.68%. murdaningsih, et al., 2017 conducted a study on spatial analysis of changes in agricultural land use to support food independence in indramayu regency. the results showed that land use in indramayu in 1994 was dominated by paddy fields with an area of 133,716 ha (65%), farms covering an area of 18,780 ha (9%) and settlements covering an area of 16,627 ha (8%). in 2015, wetland area fell to 132,097 ha (64%) and settlements increased to 18,625 ha (9%). changes in paddy fields will affect food availability.nuraeni, r., et al., 2017 examined the analysis of changes in land use and regional land use directives in bandung regency. the results showed that land use in bandung regency experienced a change with the pattern of dominant change, namely forest into built land, plantations into built land, wetland agricultural plants (tplb) 87 hendry edy, et al/ geosi vol. 4 no. 2 (2019) 78-89 into built-up land, tplb became dry land agricultural crops (tplk) and tplk became builtup land . the existing condition of land use in 2012 shows a mismatch with a space allocation of 54 ha. kusumaningrat m., et al 2017 examined the analysis of changes in land use and utilization of the 2009 and 2017 regional spatial planning (case study: boyolali regency). from the results of the study there was a change in land use to get results, economic activities decreased by 1275.9 hectares, social activities increased by 91.41 hectares, utilization of dwellings increased by 1363.16 hectares and classification of no use decreased by 210.61. changes in land suitability over a period of 8 years increased by 1291.19 hectares or 1.18%. another researcher who examined land use change was kubangun, et al. 2016 who conducted a study on the change / land use change model for critical land identification in bogor regency, cianjur regency and sukabumi regency.the results of this study indicate that land classified as critical includes sloping land with converted land use / land use. the main factor causing land conversion is the high demand for food, clothing, and shelter, due to increasing population density. 4. conclusion from the results of the research conducted by the authors it can be concluded that the construction of the southern cross road (jjls) which passes through gadingsari village, sanden district, bantul regency has an impact on land use in gadingsari village. changes in land use occurred before the construction of jjls in 2013 and after the construction of jjls in 2017. prior to the jjls settlement area of 78.90 hectares and expanded to 104.93 hectares after the construction of jjls, there was an expansion of around 32.99%. which initially amounted to 94.59 hectares to 93.32 hectares, decreased by about 1.34%, the area experienced a reduction in area from which initially had an area of 281.73 hectares to 259.95 hectares, an area of 7.73% decreased and land area reduced by 78.72 hectares to 75.74 hectares reduced around 3.78%. references ahardi muhammad a., sawitri s. & abdi s. (2015). pengaruh perubahan penggunaan lahan terhadap perubahan zona nilai tanah di kecamatan gayamsari kota semarang tahun 2004 dan 2014jurnal geodesi undip, 4(4), 316–324. 88 hendry edy, et al/ geosi vol. 4 no. 2 (2019) 78-89 beatus m. laka, uca sideng & amal (2017). perubahan penggunaan lahan di kecamatan sirimau kota ambon .jurnal geocelebes, 1(2), 43–52. fadilla restu , sudarsono b. & bashit n.(2018). analisis kesesuaian perubahan penggunaan lahan terhadap rencana tata ruang/wilayah di kecamatan penjaringan kota administratif jakarta utara menggunakan sistem informasi geografis. jurnal geodesi undip, 7(1), 109–119. kubangun siti hadjar, haridjaja o.&gandasasmita k. (2016). model perubahan penutupan / penggunaan lahan untuk identifikasi lahan kritis di kabupaten bogor , kabupaten cianjur dan kabupaten sukabumi majalah ilmiah globe, 18(1), 21–32. kusumaningrat merpati d., sawitri subiyanto&yuwono b. d. (2017) analisis perubahan penggunaan dan pemanfaatan lahan terhadap rencana tata ruang wilayah tahun 2009 dan 2017 (studi kasus : kabupaten boyolali). jurnal geodesi undip, 3, 28–43. murdaningsih, widiatmaka, munibah, l. & ambarwulan, w. (2017). analisis spasial perubahan penggunaan lahan pertanian di kabupaten indramayu. majalah ilmiah globe, 19(2), 175–184. nuraeni, r., sitorus, s.r p. & panuju, d.r. (2017). analisis perubahan penggunaan lahan dan arahan penggunaan lahan wilayah di kabupaten bandung. buletin tanah dan lahan, 1(1), 79–85. sadewo m nur, imam b. (2018). simulasi perubahan penggunaan lahan akibat pembangunan kawasan industri kendal (kik) berbasis cellular automata. majalah geografi indonesia, 32(2), 115–122. https://doi.org/10.22146/mgi.33755 wahyuni, s., guchi, h., & hidayat, b. (2014). analisis perubahan penggunaan lahan dan penutupan lahan tahun 2003 dan 2013 di kabupaten dairi. jurnal online agroekoteknologi, 2, 1310–1315. wahyunto, m.z. abidin, a. priyono &sunaryo (2001). studi perubahan penggunaan lahan di sub das citarik, jawa barat dan das kaligarang, jawa tengah. in prosiding seminar nasional multifungsi lahan sawah (pp. 39–40). 89 147 implementing google earth to enhance student’s engagement and learning outcome in geography learning ebid rocky alfatikh*, elizabeth titiek winanti, sukma perdana prasetya, eko budiyanto department of geography education, postgraduate program, state university of surabaya, lidah wetan, surabaya, 60213, indonesia *corresponding author : ebidgeografi91@gmail.com received 12 july 2019/ revised 28 march 2020/ accepted 16 april 2020/ published 30 april 2020 abstract this study aims to examine the effects of google earth on students’ engagement in learning and their learning outcome. this study employed pre-experimental design with the one-shot case study design. from the exploration directed crosswise over various areas of evaluation of 12 students in the school, it is demonstrated that dynamic learning of students in was high since it was above 75% and learning outcomes reached an average of 80. this is good considering that the passing grades set in the school was 70. the application of experiential learning methods can produce satisfactory output when viewed from student participation. by looking at the characteristics of schools where students number was less than 20, the teacher is required to develop innovative learning methods. if implemented, this may yield in the improving circumstance of the currently marginalised geography. keywords: google earth; student`s activities; geography learning. 1. introduction the absence of time is a significant hindrance to actualising gis in educational programs due to the requirement for instructors to gain proficiency with the product and to comprehend the hidden information. additionally, teachers need to prepare materials for students’ exercises, so as to allow more time for the students to become familiar with the product and fuse the device in the learning experience. teachers' emphasis on gis instruments has often been challenging because of the measure of time required to learn and apply the devices. the time related to learning gis applications has been an extensive factor in gis and related advances having just restricted execution in classrooms. fullan & langworthy (2014) state the content review changed the focus of the class to one of deep learning. one of the solution to solve this problem is the use the simple artificial intelligence that may facilitate interactions between teachers and students. google earth is geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.5 no. 1 (2020), 147-159, april, 2020 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v5i1.11987 accredited by the ministry of research , technology , and higher education of the republic of indonesia, no. 30/e/kpt/2019. 148 ebid rocky alfatikh et al / geosi vol 5 no 1 (2020) 147-159 very good to introduce the “real world” to students because it can bring students to the reality of earth surface. google composes the stage which enable the instructor ‘to bring a universe of data alive’ for students’. other study mentions that google earth is anything but difficult to utilise and shows, in a visual geospatial setting, a lot of data that applies to points that are tended to in geoscience courses and numerous other instructive settings. hong (2018) investigates approaches to upgrade basic citizenship through the instruction and learning of topography. aydin (2010) composes that geography instruction should occur in the dynamic investment of students during the time spent all encompassing and significant connections, while preparing subjects and multi-dimensional reasoning aptitudes. thankachan & franklin (2013) propose that the utilisation of google earth in the classrooms builds the consideration of the students, especially among the rudimentary students. during the investigation, through the homeroom perception, the scientists saw more consideration being paid to the exercise among primary school students than the secondary school students when google earth was being utilised. phadke (2010) argues that there are important risks and costs involved in investing in the use of google earth imagery for rhetorical communication. cuviello (2010) proposes that google earth has a spot in the classrooms, conveying a class solely with google earth is compelling at displaying the material covering the goals of the class. there is nothing to state that a blend of various strategies during one talk period is not appropriate. students need to learn. a portion of the strategies educators use in class will work for certain students and not with others. in the event that educators center around the significant foci and integrate techniques to show those things, a greater number of the students will be provided with the opportunities to learn. this strategy makes students to be actively engaged in the classroom and to actively participate in discussions. ademe (2010) proposes that dynamic learning techniques are procedures which make students dynamic members during the educating learning process. accordingly. drake (2012) states that dynamic learning offers some desire for expanding theoretical comprehension, its absence of suitable center leaves it experiencing blended discoveries. johnson et al. (2011) states that google earth can possibly bring the best of instructive innovation into instructors' study halls. it enables students to go past basic maps and worksheets to give them a special, intuitive, and connecting with taking a gander at our planet. given its assortment of additional items and layers, it is equipped for being utilised in a wide assortment of substance territories. far and away superior, google earth is an instrument that can move students over the whole globe like a flash, allowing them a chance 149 ebid rocky alfatikh et al / geosi vol 5 no 1 (2020) 147-159 to explore regions of our planet that they will in all probability never travel to. its usability, free cost, and versatility make google earth an unquestionable requirement for any educator's homeroom. conceivably, no other subject can benefit more from utilising google earth than that of geoscience training. instead of different maps or charts of land information, it is presently consolidated into a virtual, intelligent, three-dimensional model. luckily, geoscience instructors at all levels comprehend that potential and have steadily attempted to put google earth into their homerooms. patterson (2007) argues that google earth engages students by giving them the way to finish complex undertakings and by giving them significant scope in the plan of ventures. students are encouraged to mindful of spatial patterns and suggestions while not unequivocally realising they are learning geography, this can be both a potential quality and shortcoming. despite the fact that google earth does not have a huge number of apparatuses and abilities as does a genuine gis, it empowers students to find out about spatial examples and think spatially. it likewise makes way for students to participate in gis as they pose progressively mind-boggling and definite inquiries after they arrive at the utmost of google earth's utility. innovation has incessantly become part of our education: from kindergartens to graduate schools, new learning devices are progressively utilised either for in-class exercises or for learning appraisal (cauley et al., 2009). so as to plan students for the science, technology, engineering, and mathematics (stem) fields, educators in their comparing instructive controls have become pioneers in embracing instructional advancements and empowering scientific thoughts (marshall, 2009). students’ achievements on each indicator is measured as lessons on the topic of remote sensing and gis take place. students will independently operate the google earth software and interpret land appearances on the surface of the earth, then students also do labeling and temporally analyse the changes in land that occur based on aerial photographs on google earth. although it is not as complex as gis software, it is expected that this simple software can represent the existence of remote sensing technology and gis because so far the difficulty in teaching this topic is the small number of teachers using technology to aid their teaching. gökçea (2015) states that the impact of various strategies and methods over students’ aptitudes ought to be resolved. schools' framework ought to be refreshed and redesigned, and separate examinations researching the impact of schools' foundation over students’ abilities ought to be structured. in-administration preparing projects ought to be led so as to assist 150 ebid rocky alfatikh et al / geosi vol 5 no 1 (2020) 147-159 educators with finishing their insufficiencies in planning and utilising maps, for example, gis, google map, and google earth. previous studies do not measure in depth the activities of students in the class relating to their interactions with teachers and peers to overcome the problem of learning geography by using google earth. this research not only examines in theory but also the application of google earth software in increasing student activity, focus of research is to observe the correlation between use of google earth and student’s activities. this study measures the indicators of student’s activities, such as (1) participation in carrying out their learning tasks; (2) involvment in problem solving; (3) questions for other students or teachers if they do not understand the problems they face; (4) involvement in group discussions according to the teacher's instructions;(5) assessment of his ability and results the results obtained;(6) training in solving problems;(7) ability to complete tasks. this study aims to examine the effects of google earth on students’ engagement in learning and their learning outcome. 2. methods this study employed pre-experimental design with the one-shot case study design. data were collected by using observation sheets. analysts at that point gauge data from a writing survey in light of their own worries and circumstance. field observations were used to measure students activity during interpreting images with criteria as follows: (1) participating in carrying out their learning tasks; (2) involving in problem solving; (3) asking other students or teachers if they cannot solve aproblem ; (4) trying to find various information needed for problem solving; (5) carrying out group discussions in accordance with the teacher's instructions; (6) assessing his abilities and the results obtained; (7) training themselves in solving problems or similar problems; (8) using or applying what is obtained in completing the task or problem it faces. there were external variables that influenced the shape of the dependent variable. therefore, the experimental result which was the dependent variable was not solely affected by the independent variable. this was because there was no control variable and the sample was not randomly selected. table 1. treatment schemes in the experimental and observation classes group dependent variable observation (r) experiment x o 151 ebid rocky alfatikh et al / geosi vol 5 no 1 (2020) 147-159 x = treatment using google earth o = observation during the activity the researcher wanted to find out the effects of the treatment given to students in the form of aerial photo interpretation activities from google earth and temporally analyze their chosen location. this study used the following scheme: (a) participating in carrying out their learning tasks, (b) involving in problem solving, (c) asking other students or teachers if they do not understand the problems they face, (d) trying to find various information needed for problem solving, (e) carrying out group discussions according to the teacher's instructions, (f) assessing his ability and results the results obtained, (g) training in solving problems; (h) completing tasks. table 2. description of each aspect scoring remark 1 need improvement 2 fair 3 good 4 very good calculation of the average percentage of indicators of student participation above are as follows:iks= ∑ x 100% (1) i ks : student activity index∑s ∶ the total number of students average score f : frequency of students 3. results and discussion the assessment of the activities of students in the interpretation of aerial photographs were based on the accuracy of the object recognition made by students, because this is the most vital part in image interpretation. aerial photography as the oldest image in remote sensing has the most complete element of interpretation compared to the interpretation of other images. the aerial photo in question is an aerial photo from google earth. google earth is an interactive mapping application released by google. google earth displays a map of the globe, topography, terrain that can be overlaid by road, location building or other geographic information. after going through instrument validation, the following are the results obtained in this study. 152 ebid rocky alfatikh et al / geosi vol 5 no 1 (2020) 147-159 table 3. results of observation of student activity student’s name aspect of activities observed (scores) total % mean a b c d e f g h student a 4 3 3 4 3 2 2 3 24 67 77 student b 4 4 4 4 4 4 3 3 30 83 student c 3 4 3 4 4 3 3 3 27 75 student d 3 3 3 4 4 4 4 3 28 78 student e 3 4 4 4 4 3 3 3 28 78 student f 4 4 3 3 3 4 3 4 28 78 student g 3 4 4 3 3 3 4 4 28 78 figure 1. aspect of activities observed the present investigation was intended to comprehend the effect on students’ learning in a social examinations study hall with google earth intervened guidance. google earth enables students to finish complex assignments by providing them the and extensive scope in the structure of ventures. students were made mindful of spatial patterns and suggestions while not expressly realizing they were learning topography, this can be both a potential quality and shortcoming. students freely worked on the google earth programming and 0 10 20 30 40 50 60 70 80 90 100 a b c d e f g percentage (%) 153 ebid rocky alfatikh et al / geosi vol 5 no 1 (2020) 147-159 translated land appearances on the outside of the earth, at that point students likewise did marking and transiently dissect the adjustments in a land that happen dependent on airborne photos on google earth. in spite of the fact that google earth does not have a huge number of devices and capacities as does a genuine gis, it empowers students to find out about spatial examples and think spatially. the utilization of google earth in the study hall will build consideration of the students. table 4. student’s scores (learning outcome) students scores mean student a 75 80 student b 90 student c 80 student d 80 student e 85 student f 80 student g 70 figure 2. student’s learning outcome 0 10 20 30 40 50 60 70 80 90 100 a b c d e f g scores 154 ebid rocky alfatikh et al / geosi vol 5 no 1 (2020) 147-159 based on table 3 above, it can be seen that the learning outcomes of students reached an average of 80. this was very good considering the passing grades in the school was below it, namely 70. based on the results of the aboveit is known that the application of experiential learning methods can produce satisfactory output when viewed from student participation. the results of this study are reinforced by prawindia (2016) proposition that based on the results of observation and identification of geographic teaching materials used by students, there are still some shortcomings. analysis of geographic content includes the use of geographic concepts and formal geographic objects in the form of linkages of objects in terms of spatial, territorial, and environmental aspects. with expanding student support, different elements are relied upon to increment in particular self-efficacy. self efficacy is an individual's beliefin their capacity to prevail with regard to accomplishing objectives. palmer (2013) states that students reacted decidedly to learning landforms and their related developmental procedures utilizing google earth and advantageous representations. the results of this study are reinforced by collins (2018) compared customary paper maps and computerized maps to decide if various media significantly effective to improve students' mindfulness and specific sorts of spatial reasoning aptitudes. in light of the examination of inside and out meetings with center school students and educators in the wake of executing a progression of geospatial learning exercises, the creators reason that expanded introduction to maps and spatial reasoning exercises can improve students' spatial reasoning abilities paying little mind to media. yuda (2011) states that spatial learning has a different way of testing students' spatial thinking skills, namely by means of games, such as puzzles, video games, and maps. this was done because his research involved elementary education studentsas respondents, so that such tests were considered to be more familiar and not to change the situation. the results of the study for three meetings showed an increase in the activity of teachers and students at each meeting with an average of 92.15%, categorized as very good. experience-based learning is useful because the application of experiential learning learning models with correct steps is proven to increase the value of the process and student learning outcomes. furthermore, the researchers also provide advice to schools to complement learning media that support the learning process so that learning can take place actively, innovatively, creatively and pleasantly. jo & hong (2018) investigate that urge proceeded with look into endeavors to amass information about educational program, guidance, and evaluation, just as 155 ebid rocky alfatikh et al / geosi vol 5 no 1 (2020) 147-159 instructors' expert advancement that can assist students with turning out to be 21st century residents furnished with geospatial proficiency. fieldwork also needs to be developed in experiential learning, because field practice is very good for stimulating students' brains to be able to remember the activities and knowledge carried out. components in product development need to be considered, because they are tailored to the learning needs of students. a more specific explanation for each indicator is as follows: table 4 shows that of all of 7 students showed very good participation in carrying out their learning tasks. 3 students showed very good indicators in the contribution of completing their assignments. while the other 4 students were known to get a score of 3 which was a good indicator. abdullah et al. (2012) argue that the students concurred on the significance of friends in the learning procedure. notwithstanding, students like to be in a gathering like them in terms of decisiveness in the study hall. in general, the two gatherings of inactive and dynamic students recognized the significance of students to shout out in the class. from table 4 it is known that from a total of 7 students, 5 students got very good indicators and only 2 students got good indicators. this shows that students are able to contribute to problem solving in class discussions. samson’s (2015) techniques that draw in and persuade students advances further learning and encourages the improvement of powerful critical thinking and basic reasoning aptitudes. from table 4 it is known that from a total of 7 students, 3 students got very good indicators and 4 students got good indicators. this shows that students were able to develop the skill to ask questions during the discussion process. from table 4 it is known that from a total of 7 students, 5 students got very good indicators and only 2 students got good indicators. this shows that students are able to solve the problems contained in the discussion theme. from table 4 it is known that from a total of 7 students, 4 students got very good indicators and 3 students got good indicators. this shows that students are able to carry out group discussions according to the teacher's instructions. instructors need to discover approaches to fuse dynamic procedures such that sparkles intrigue and enthusiasm for students. consolidating a constructivist structure that supports such a methodology might be an answer, alongside the preliminary work in preparing students to take part in such an educational move, as in certain orders this training strategy might be considered outside of the standard of what is normal for certain students in the classrooms setting. 156 ebid rocky alfatikh et al / geosi vol 5 no 1 (2020) 147-159 from table 4 it is known that from a total of 7 students, 3 students got very good indicators, 3 students got good indicators and 1 student got fair indicator. this shows that students are able to assesstheir ability and their learning result. explicit criteria to elevate quality criticism should be grown with the goal that coordinated effort can be increasingly effective and advantageous to every student and accordingly elevate students' chances to assume liability for their learning (ndoye, 2017). oral and moment input should be underscored and advanced dependent on the consequences of this examination. advantages from self and friend appraisal can be expanded additionally if exercises are planned in a manner that enables students to apply their evaluative aptitudes. these evaluative abilities will assist students with surveying their work and that of others regarding expected execution criteria so as to become dynamic students and better arranged to take part in deep rooted learning. while this examination shows the advantages of companion and self-appraisal, apparently not all students saw their interconnection and how they should expand on one another. earlier research (reinholz, 2016) has demonstrated the need not exclusively to build up the connection among friends and self-appraisal, however, to make evident and clarify the systems through which this linkage occurs. from table 4 it is known that from a total of 7 students, 2 students got very good indicators, 4 students got good indicators and 1 student got fair indicator. this shows that students are able to train in solving problems or similar problems. learning the pace of selfguideline in students with preparing in critical thinking abilities is altogether more than students without these training (ahghar, 2012). from table 4 it is known that from a total of 7 students, 2 students got very good indicators and 2 students got good indicator. this shows that students were able to be trained in solving problems or similar problem. students' view of authority and execution objectives demonstrated various examples of connection with learning techniques, the inclination for testing assignments, the frame of mind toward the class, and convictions about the reasons for progress and disappointment. marra et al. (2015) explore that students praise the exploration of their fieldwork area using google earth and qgis, and both the students that did and did not use gis during the fieldwork indicate the preparatory gis-assignment as the most valuable for their fieldwork. this is certainly very good if it is correlated with the situation of marginalized geography (yunus, 2010). with the increasing activity of students, it is expected that this can eliminate the impression that geography is a science that is not too favored by students. in spite of the fact that google earth enables students to investigate the earth in increasingly unique and 157 ebid rocky alfatikh et al / geosi vol 5 no 1 (2020) 147-159 intuitive manners, there are a few constraints in instructive settings, for example, high data transfer capacity request, and requirement for preparing to comprehend the google earth interface. 4. conclusion . the application of learning methods which utilsied google earth technology has proven to have an impact on increasing student activity. therefore, students were able to develop their hard and soft skills. this can be good if applied in all schools. because geography subject of the remote sensing and gis chapter can be less effective if conducted by the lecturing method. the teacher must be able to understand the characteristics of students and the characteristics of the chapter to be taught because each chapter in geography is unique. when students are engaged in the learning, they will enjoy to study geography, so that this can eliminate the impression that geography is a difficult lesson which involes a lot of memorizing activities. it is expected that if more schools implement this method, tgeography marginalization will fade away and will eventually disappear. this is our shared responsibility as stakeholders and actors in the field of geography. conflict of interest the authors declare that there is no conflict of interest with any financial, personal, or other relationships with other people or organizations related to the material discussed in the article. references abdullah, m. y., bakar, n. r. a., & mahbob, m. h. (2012). student's participation in classroom: what motivates them to speak up?. procedia-social and behavioral sciences, 51, 516-522. ademe, b. (2010). general learning-teaching methods and techniques. addis ababa: addis ababa university press. aydin, f., & kaya, h. (2010). geography teachers’ views towards vocational geographic information systems (gis) seminar. middle-east journal of scientific research, 6(6), 631-636. cauley, f. g., aiken, k. d., & whitney, l. k. (2009). technologies across our curriculum: a study of technology integration in the classroom. journal of education for business, 85(2), 114-118. 158 ebid rocky alfatikh et al / geosi vol 5 no 1 (2020) 147-159 collins, l. (2018). student and teacher response to use of different media in spatial thinking skill development. international journal of geospatial and environmental research, 5(3), 3. cuviello. (2010). evaluating google earth in the classroom. thesis. united states military academy: faculty professional development program. drake, j. r. (2012). a critical analysis of active learning and an alternative pedagogical framework for introductory information systems courses. journal of information technology education, 11, 39-52. fullan, m., & langworthy, m. (2014). a rich seam: how new pedagogies find deep learning. london: pearson gökçe, n. (2015). social studies in improving students’ map skills: teachers’ opinions. educational sciences: theory & practice, 15(5) hong, j. e. (2018). critical citizenship education through geography. international journal of geospatial and environmental research, 5(3), 7. jo, i., & hong, j. e. (2018). geography education, spatial thinking, and geospatial technologies: introduction to the special issue. international journal of geospatial and environmental research, 5(3), 1. johnson, n. d., lang, n. p., & zophy, k. t. (2011). overcoming assessment problems in google earth-based assignments. journal of geoscience education, 59(3), 99-105. marra, w. a., van de grint, l., alberti, k., & karssenberg, d. (2017). using gis in an earth sciences field course for quantitative exploration, data management and digital mapping. journal of geography in higher education, 41(2), 213-229. marshall, s. p. (2009). re-imagining specialized stem academies: igniting and nurturing decidedly different minds, by design. roeper review, 32(1), 48-60 palmer, r. e. (2013). learning geomorphology using aerial photography in a web-facilitated class. review of international geographical education online, 3(2), 118-137. patterson, t. c. (2007). google earth as a (not just) geography education tool. journal of geography, 106(4), 145-152.doi:10.1080/00221340701678032 phadke, r. (2010). defending place in the google earth age. ethics, place & environment, 13(3), 267-281.doi:10.1080/1366879x.2010.516495 prawindia, l., fatchan, a., & astina, i. k. (2016). pengembangan bahan ajar geografi struktur buku cambridge fundamentals of geography untuk kelas xi sma/ma materi sebaran barang tambang. jurnal pendidikan geografi: kajian, teori, dan praktek dalam bidang pendidikan dan ilmu geografi, 21(1), 53-62. samson, p. l. (2015). fostering student engagement: creative problem-solving in small group facilitations. collected essays on learning and teaching, 8, 153-164. 159 ebid rocky alfatikh et al / geosi vol 5 no 1 (2020) 147-159 thankachan, b., & franklin, t. (2013). impact of google earth on student learning. international journal of humanities and social science, 3(21), 11-16 yuda, m. (2011). effectiveness of digital educational materials for developing spatial thinking of elementary school students. procedia-social and behavioral sciences, 21, 116-119. yunus, h.s., (2010). metodologi penelitian wilayah kontemporer, yogyakarta : pustaka pelajar research article seasonal variability of waterlogging in rangpur city corporation using gis and remote sensing techniques md. naimur rahman1,*, sajjad hossain shozib2 1department of geography and environmental science, begum rokeya university, rangpur, park mor, modern, rangpur, 5404, bangladesh 2department of environmental engineering, nanjing forestry university, no.159 longpan road, nanjing, 210037, china received 28 november 2020/revised 17 july 2021/accepted 28 july 2021/published 17 august 2021 abstract waterlogging hazard is a significant environmental issue closely linked to land use for sustainable urbanization. ndwi is widely and effectively used in identifying and visualizing surface water distribution based on satellite imagery. landsat 7 etm+ and landsat 8 oli tirs images of pre and post-monsoon (2002, 2019) have been used. the main objective of this study is to detect the seasonal variation of waterlogging in rangpur city corporation (rpcc) in 2002 and 2019. in the present study, we used an integrated procedure by using arcgis raster analysis. for pre and post-monsoon, almost 93% accuracy was obtained from image analysis. results show that in 2002 during the pre and post-monsoon period, waterlogged areas were about 159.58 km2 and 32.32 km2, respectively, wherein in 2019, the changes in waterlogged areas are reversed than 2002. in 2019, during pre-monsoon, waterlogged area areas were 122.79 km2, and during post-monsoon, it increased to 127.05 km2. the research also depicts that the trend of the waterlogging situation largely depends on seasonal rainfall and a flawed drainage system. keywords : seasonal variation; waterlogging; remote sensing; gis; rangpur city corporation 1. introduction waterlogging is considered a global concern, affecting 10-15 million hectares of wheat land annually and causes 20% 50% of total global yield loss. loss of grain crops such as field peas, canola, barley, lentils, lupins, and chickpeas also get affected due to severe waterlogging worldwide. in the usa, 16% of soil, in russia 10% of agricultural croplands and irrigated crop production in bangladesh, india, china, and pakistan get harmed just because of waterlogging (bakker et al., 2007; hossain & uddin, 2011; romina et al., 2018; solaiman et al., 2007; yaduvanshi et al., 2012). *corresponding author. email address : naimurbrur@gmail.com (md. naimur rahman) geosfera indonesia vol. 6 no. 2, august 2021, 143-156 p-issn 2598-9723, e-issn 2614-8528 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v6i2.21006 143 *corresponding author. email address : naimurbrur@gmail.com (md. naimur rahman) mailto:01naimur@gmail.com mailto:01naimur@gmail.com 144 md. naimur rahman & sajjad hossain shozib / geosfera indonesia 6 (2), 2021, 143-156 water does not usually penetrate deep into the flat terrain, which increases the depth of groundwater since the subsurface land is filled. it is indeed a significant environmental hazard and is found worldwide (bowonder et al., 1986), such as in bangladesh (minar et al., 2013), india (choubey, 1998; chowdary et al., 2008; sahu, 2014), china (quan et al., 2010), pakistan (qureshi et al., 2008) and others. northern bangladesh is exceptionally susceptible to environmental and quasi-natural potential hazards, such as waterlogging. siltation has become one of the key reasons for waterlogging that blocks the river water flow and causes congestion by the upstream drainage. in southern bangladesh, thousands of speople have lost their ability to make a proper living just because of waterlogging, particularly poor and landless farmers, share-holders, daily wage laborers, small traders, and others (shaibur et al., 2019). various previous studies have shown that gis and rs techniques are useful for detecting and mapping waterlogged areas for different study areas (guha et al., 2020; hassan & mahmud-ul-islam, 2014; khine et al., 2018; mahmud et al., 2017; sar et al., 2015). few authors mentioned adaptation strategies of waterlogging in some districts of southern bangladesh which have been described in the following literature (islam et al., 2020; shaibur et al., 2019). the causes and consequences of waterlogging have been shown in (awal & islam, 2020) after analyzing using gis and rs image analysis. visualization of waterlogged areas was carried out using traditional methods, as well as the land survey. still, these methods are time-consuming for regional studies and not even economically feasible. the combination of gis with rs is an incredible alternative to the conventional method and assessment strategies in the degree of spatiotemporal differences in waterlogged regions (chowdary et al., 2008). a very few research papers have been found about the detection of waterlogging areas in different areas of bangladesh, especially focusing on seasonal variation of waterlogging. most importantly, found researches were focusing on some southern districts of bangladesh. to date, no researches have been found which is focusing on any part of northern bangladesh. this paper is could be the pioneer of its category of novelty for evaluating the seasonal variation of waterlogging area detection for northern bangladesh using gis and rs, especially for emerging cities like rangpur city corporation (rpcc). in a new city like rpcc, waterlogging is one of the most severe problems because of improper drainage systems and narrow drains in the city area. this research is unique in a way that will help respective authorities and planners to realize the actual situation and develop a proper and planned drainage system to avoid waterlogging. ndwi application has significant importance in classifying waterlogged areas and determining waterlogged risk 145 md. naimur rahman & sajjad hossain shozib / geosfera indonesia 6 (2), 2021, 143-156 assessment and hazard mapping quickly, efficiently, and accurately. therefore, the main objective of this study is to assess waterlogged areas in rpcc for both pre-monsoon and post-monsoon seasons in 2002 and 2019 where a reasonable attempt using gis and rs has been undertaken. 2. methods rangpur is one of the new city corporations in bangladesh, with an area of 203 km2. rangpur city corporation is located on the banks of the river ghaghat. this river serves as the natural drainage of the city. the human-made shyamasundari canal is the leading wastewater channel in the city. rpcc is located at the coordinate of 25°37ʹ to 25°54ʹ north latitude and 89°09ʹ to 89°21ʹ east latitude. rangpur is classified as a high-temperature climatic zone because of its tropical wet and dry climatic phenomena (islam & sarker, 2016). in the rpcc, permanent water sources such as rivers, lakes, ponds, and reservoirs cover 2235 ha, while seasonal water sources such as floods, swamps, and marshy areas cover 2032 ha. furthermore, in the research area, planted trees, cultivated land, uncultivated soil, and built up area each contributed 1016, 4267, 3251, and 7518 ha, respectively (islam & sarker, 2016). figure 1. study area with physical features (rangpur city corporation). source: adopted, modified and regenerated from islam & sarker (2016) 146 md. naimur rahman & sajjad hossain shozib / geosfera indonesia 6 (2), 2021, 143-156 the research was carried out with satellite multitemporal landsat 7 and landsat8 images collected from the us geological survey (https:/earthexplorer.usgs.gov/). however, the path and row were selected 138 and 042 for image acquisition (table 1) for 2002 and 2019. depending on the april and november months of the valued year, the collected satellite images representing the pre-monsoon and post-monsoon seasons. the cloud-free environment for preparing the ndwi classification was ensured by obtained images (chen & zhu, 2020). ndwi mapping, image classification, image processing, and change detection were performed through arcmap10.6. to show a comparison of the average rainfall of bangladesh and rpcc and more rainfall in april 2002 (figure 4) data has been collected from bangladesh meteorological department (2019) and origin pro 8.5 has been used to prepare the figure. figure 2. methodological flow chart of waterlogging in rpcc 147 md. naimur rahman & sajjad hossain shozib / geosfera indonesia 6 (2), 2021, 143-156 table 1. landsat images season satellite image date of acquisition sensor path/ row spectral resolution projection pre-monsoon landsat 7 april 13, 2002 etm+ 138/42 landsat 8 april 20, 2019 oli tirs post-monsoon landsat 7 november 7, 2002 etm+ 138/42 landsat 8 november 30, 2019 oli tirs 3.2 classification and accuracy assessment of normalize difference water index (ndwi) normalize difference water index(ndwi) was developed to detect water bodies' changes (mcfeeters, 1996). in this study, ndwi is used (mahmud et al., 2017) to analyze the seasonal waterlogged area in rpcc. the index can be seen in eq.1 : ndwi = pg pnir/pg + pnir (1) where spectral reflectance is pg in the green band, and spectral reflectance in nir is indicating pnir. the classified method could be more specified for landsat 7 and landsat 8 derivation method, can be seen in eq.2 : ndwi for landsat 7: band 2 (green) – band 4 (nir)/ band 2 (green) + band 4 (nir) (2) ndwi for landsat 8 can be seen in eq.3 : band 3 (green) – band 5 (nir)/ band 3 (green) + band 5 (nir) (3) in these methods’ positive high reflectance of ni rand green band is the indication of water bodies. furthermore, positive and negative ndwi value demonstrates water and vegetation range from -1 to +1 value (özelkan, 2020). later, accuracy evaluation was applied to obtain the ndwi 's transparent pixel value. in addition, validation of the kappa coefficient, overall precision, and accuracy was carried out (guha et al., 2020; khine et al., 2018). following the google earth photos, 350 points were randomly selected for the application of precision assessment. study region means rainfall data were compared to country mean rainfall data to provide a clear overview between rainfall and waterlogging based on the month from 2002 to 2019. furthermore, rainfall data were collected from bangladesh meteorological department (2019). 138/42 138/42 30 m 30 m utm/wgs 84 utm/wgs 84 148 md. naimur rahman & sajjad hossain shozib / geosfera indonesia 6 (2), 2021, 143-156 4. results and discussion table 2 illustrates the overall accuracy and kappa coefficient. the demonstration also shows overall accuracy is higher than 89% in each period of 2002 and 2019. in addition, we observed the kappa coefficient more than 0.83 in all images. a measurement of comparison was taken between sampling points (350 points) and google earth images for the same period to validate ndwi classifications. besides, more than 90% validation values are counted for each period. author opinions here as good accuracy was identified for kappa statistics, overall accuracy, and validation. table 2. accuracy assessment user accuracy producer accuracy classification accuracy kappa statistics period vegetation and builtup area waterlogged area vegetation and builtup area waterlogged area premonsoon 2002 85 100 75.84 100 91.00% 0.899 postmonsoon 2002 96 89 90 100 89.57% 0.835 premonsoon 2019 100 90 100 95 93.95% 0.900 postmonsoon 2019 90 100 83.33 100 96.88% 0.937 in the years 2002 and 2019, waterlogged areas during pre-monsoon and post-monsoon periods in the study site were defined by gis and rs techniques. the areas where waterlogged condition remains all-around year are perpetual waterlogged areas. satellite images of april have been considered for pre-monsoon (most dry season) after excerpting areas under small lakes and ponds. in opposite, throughout the monsoon period, excessive rainfall causes seasonal inundation. therefore, satellite images of water bodies for november have been considered (after the monsoon period) to detect the change of waterlogged areas (seasonal). for the year 2002, figure 3(a) shows that mostly the northwestern part is waterlogged during pre-monsoon (early monsoon), but those areas are not permanently waterlogged. because figure 3(b) shows only a very few areas across rpcc are waterlogged, which is noticeable. however for the year 2019, in figure 4(a) it is found that the north-west central part of rpcc is mostly waterlogged, not other parts, north-east central and southcentral part of rpcc is less waterlogged during pre-monsoon. after the monsoon, figure 149 md. naimur rahman & sajjad hossain shozib / geosfera indonesia 6 (2), 2021, 143-156 4(b) defines more areas than pre-monsoon area waterlogged, which means that estimated waterlogged areas increased. figure 3. (a) map showing waterlogged areas in rpcc during pre-monsoon in 2002 (left), (b) map showing waterlogged areas in rpcc during post-monsoon in 2002 (right). monsoon in 2002 was early (figure 5a), especially in april rainfall was third highest of 2002 (in mm). therefore, during the pre-monsoon period in 2002 waterlogging areas in rpcc was more than comparatively in 2019 pre-monsoon (figure 4a). 150 md. naimur rahman & sajjad hossain shozib / geosfera indonesia 6 (2), 2021, 143-156 figure 4. (a) map showing waterlogged areas in rpcc during pre-monsoon in 2019 (left), (b) map showing waterlogged areas in rpcc during post-monsoon in 2019 (right). figure 5. (a) showing average rainfall of the year 2002. where in april rpcc containing heavy average rainfall. (b) comparison of average rainfall in bangladesh and rpcc (bangladesh meteorological department, 2019) 151 md. naimur rahman & sajjad hossain shozib / geosfera indonesia 6 (2), 2021, 143-156 based on image analysis of the gis environment, in rpcc, waterlogged areas changes have been considered (table 3). it is found that in 2002 during the pre and postmonsoon period, waterlogged areas were about 159.58 km2 and 32.32 km2, respectively, which is 49.35% and 9.99% of the total area of rpcc. the result clearly shows decreased waterlogged area during post-monsoon than pre-monsoon 127.26 km2 by area (39.36%). for the year 2019, the changes in waterlogged areas are reversed than in 2002. in 2019, during pre-monsoon, waterlogged area areas were 122.79 km2 (37.98%), and during post-monsoon, it increased to 127.05 km2, where the increase rate is 1.31%. table 3. waterlogged areas variation during pre-monsoon and post-monsoon periods in 2002 and 2019 in rpcc year pre-monsoon post-monsoon seasonal variation km2 % km2 % km2 % 2002 159.58 49.35 32.32 9.99 127.26 39.36 2019 122.79 37.98 127.05 39.29 4.25 1.31 lack of a proper drainage system and heavy rainfall in the monsoon period causes waterlogging in rpcc. figure 5 is showing, at some points, rainfall in the rpcc area is more than the average rainfall of bangladesh. the study revealed high accuracy and validated data, which indicates transparent and essential observation. an analyzed value of more than 89% for overall accuracy, kappa > 0.83 and validation value > 90 was observed where various investigations found kappa > 0.75 is very good for measuring accuracy (abbas et al., 2020; foody, 2020; morales-barquero et al., 2019). hazard and risk for waterlogging issue is a global problem that causes any country's impact economy (sar et al., 2015). in recent times it is reported that the study area is vulnerable to waterlogging due to heavy rainfall (the daily star, 2021). after analyzing landsat images, the waterlogging problem is found in the current study area during both the pre and post-monsoon periods. unpsredictable monsoon rainfall has been found from this study in both 2002 and 2019, wherein in the year 2002 there had been early monsoon, and in 2019 it was regular monsoon rainfall. however, waterlogging, floods, drought, and massive life losses could be determined through rainfall variability (rahman & islam, 2019; ullah et al., 2018). the present study reveals the net change of waterlogged area for pre-monsoon is reduced from 49.35% to 37.98% where the post-monsoon inundated area is increased largely which is 9.99% to 39.29%. thus, meteorological observation in figure 5 and table 3 demonstrates an increase of waterlogged area in 2002 for the pre-monsoon season which corresponds to 2019. hence, in the pre-monsoon season of 2002 high land, orographic 152 md. naimur rahman & sajjad hossain shozib / geosfera indonesia 6 (2), 2021, 143-156 rainfall, deep and low depressional behavior caused heavy rainfall as well as waterlogged area in the present area of study (mannan & karmakar, 2008). additionally, we detected heavy rainfall in the post-monsoon season for the year 2019 compared with 2002. in recent times the geographical condition of the northern part of bangladesh as it is situation closely assam and meghalaya hill and complex climate change pattern is the responsible factor for higher rainfall intensity during the post-monsoon season in rpcc (montes et al., 2021; islam et al., 2020). furthermore, islam et al. (2020) found an upward trend of rainfall, leading to an increased amount of waterlogged areas in the study area. the present study also demonstrates the compared rainfall data of the study area and the entire country, which indicates the measurement of higher rainfall trend during monsoon season except for the pre-monsoon period of 2002, which indicates increased rainfall during the mentioned pre-monsoon period. however, seasonal flooding also causes waterlogged areas (huda et al., 2019; shaibur et al., 2019). when analyzing our data, we found that the study area is vulnerable to seasonal flooding (talukdar et al., 2020). about flooding study area getting higher waterlogged areas, which varies seasonally. besides, rising monsoon rainfall, upstream river flow by human intervention, unplanned aquaculture, and infrastructure can be explained as causes of waterlogging in the study area (awal & islam, 2020; ayyam et al., 2019; islam et al., 2020). 4. conclusion waterlogging hazard, risk, and vulnerability in rpcc combined with raster modeling by using integrated gis and rs techniques can be useful for developing the drainage system of the city and sustainable management of water resources. the current study's outcome can be used by city planners, engineers, local people, and policymakers to identify and locally develop the most waterlogged areas. thus an advanced drainage pattern could be developed based on the identified location of the findings. however, this research can be done using substantially more data for a long period to derive a trend in progress and seasonal fluctuations in waterlogging. enormous statistical analysis can enhance the subtraction of ndwi for a more accurate depiction. the construction, upgrading of the necessary infrastructure of local weld, and excavation of silted ghaghat river beside rpcc and shyamasundari canal in rpcc can also be as useful to mitigate the waterlogging problem in the rpcc area. conflict of interest the authors declare that there is no conflict of interest. 153 md. naimur rahman & sajjad hossain shozib / geosfera indonesia 6 (2), 2021, 143-156 acknowledgements authors would like to acknowledge ruhul amin for his for his valuable comments on this study, md. morshadul islam for his suggestions to improve language of this manuscript. references abbas, z., & jaber, h. s. (2020). accuracy assessment of supervised classification methods for extraction land use maps using remote sensing and gis techniques. in iop conference series: materials science and engineering (vol. 745, no. 1, p. 012166). iop publishing. awal, m. a., & islam, a. t. (2020). water logging in south-western coastal region of bangladesh: causes and consequences and people’s response. asian journal of geographical research, 9-28. https://doi.org/10.9734/ajgr/2020/v3i230102. ayyam, v., palanivel, s., & chandrakasan, s. (2019). land and water conservation: dealing with agriculture and aquaculture conflicts. coastal ecosystems of the tropicsadaptive management (pp. 391-406): springer.http://dx.doi.org/10.1007/978-981-138926-9_17. bakker, d., hamilton, g., houlbrooke, d., spann, c., & van burgel, a. (2007). productivity of crops grown on raised beds on duplex soils prone to waterlogging in western australia. australian journal of experimental agriculture, 47(11), 1368-1376. https://doi.org/10.1071/ea06273. bangladesh meteorological department (2019). climate data portal. retrieved from http://live3.bmd.gov.bd/. bowonder, b., ramana, k., & rajagopal, r. (1986). waterlogging in irrigation projects. sadhana, 9(3), 177. https://doi.org/10.1007/bf02811964. chen, j., & zhu, w. (2020). consistency evaluation of landsat-7 and landsat-8 for improved monitoring of colored dissolved organic matter in complex water. geocarto international, 1-12. https://doi.org/10.1080/10106049.2020.1734872. choubey, v. (1998). assessment of waterlogging in sriram sagar command area, india, by remote sensing. water resources management, 12(5), 343-357. https://doi.org/10.1023/a:1008053705535. chowdary, v., chandran, r. v., neeti, n., bothale, r., srivastava, y., ingle, p., . . . sharma, j. (2008). assessment of surface and sub-surface waterlogged areas in irrigation command areas of bihar state using remote sensing and gis. agricultural water management, 95(7), 754-766. https://doi.org/10.1016/j.agwat.2008.02.009. foody, g. m. (2020). explaining the unsuitability of the kappa coefficient in the assessment and comparison of the accuracy of thematic maps obtained by image classification. remote sensing of environment, 239, 111630. https://doi.org/10.1016/j.rse.2019.111630. guha, s., govil, h., & besoya, m. (2020). an investigation on seasonal variability between lst and ndwi in an urban environment using landsat satellite data. geomatics, natural hazards and risk, 11(1), 1319-1345. https://doi.org/10.1080/19475705.2020.1789762. https://iopscience.iop.org/article/10.1088/1757-899x/745/1/012166/meta https://iopscience.iop.org/article/10.1088/1757-899x/745/1/012166/meta https://iopscience.iop.org/article/10.1088/1757-899x/745/1/012166/meta https://doi.org/10.9734/ajgr/2020/v3i230102 http://dx.doi.org/10.1007/978-981-13-8926​-9_17 http://dx.doi.org/10.1007/978-981-13-8926​-9_17 https://doi.org/10.1071/ea06273 http://live3.bmd.gov.bd/ https://doi.org/10.1007/bf02811964 https://doi.org/10.1080/10106049.2020.1734872 https://doi.org/10.1023/a:1008053705535 https://doi.org/10.1016/j.agwat.2008.02.009 https://doi.org/10.1016/j.rse.2019.111630 https://doi.org/10.1080/19475705.2020.1789762 154 md. naimur rahman & sajjad hossain shozib / geosfera indonesia 6 (2), 2021, 143-156 hassan, m. s., & mahmud-ul-islam, s. (2014). detection of waterlogging areas based on passive remote sensing data in jessore district of khulna division, bangladesh. international journal of scientific and research publications (ijsrp), 4 (12). hossain, m. a., & uddin, s. n. (2011). mechanisms of waterlogging tolerance in wheat: morphological and metabolic adaptations under hypoxia or anoxia. australian journal of crop science, 5(9), 1094. huda, n., terao, t., murayama, s., & suenaga, y. (2019). detection of waterlogging floods in bengal mega-delta from people’s perception underpinned by hydrometeorological dataset. journal of recent advances in marine science and technology, 13. islam, a., rahman, m. s., khatun, r., & hu, z. (2020). spatiotemporal trends in the frequency of daily rainfall in bangladesh during 1975–2017. theoretical and applied climatology, 141(3), 869–887. https://doi.org/10.1007/s00704-020-03244-x. islam, e., khan, s. a., khaleque, m. a., & ahammed, s. s. (2020). waterlogging in the southwest coastal areas of bangladesh: local adaptation techniques and challenges. american scientific research journal for engineering, technology, and sciences (asrjets), 68(1), 112-119. islam, w., & sarker, s. c. (2016). monitoring the changing pattern of land use in the rangpur city corporation using remote sensing and gis. journal of geographic information system, 8(04), 537. https://doi.org/10.4236/jgis.2016.84045. khine, m. m., maw, y. y., & win, k. m. m. (2018). change analysis of indices (ndwi, ndvi, ndbi) for mawlamyine city area using google earth engine. j. myanmar acad. arts sci., 16 (5). mahmud, m. i., mia, a. j., uddin, m. r., rahman, m. m., & rahman, m. h. (2017). assessment on seasonal variations in waterlogging using remote sensing and gis techniques in satkhira district in bangladesh. barisal university journal, 4(1):67-80. mannan, m., & karmakar, s. (2008). climatic feature of heavy rainfall activities in monsoon season and its socio-economic impact in bangladesh. in proceedings of saarc seminar on application of weather and climate forecasts in the socio-economic development and disaster mitigation (pp. 5-7). mcfeeters, s. k. (1996). the use of the normalized difference water index (ndwi) in the delineation of open water features. international journal of remote sensing, 17(7), 1425-1432. https://doi.org/10.1080/01431169608948714. minar, m. h., hossain, m. b., & shamsuddin, m. (2013). climate change and coastal zone of bangladesh: vulnerability, resilience and adaptability. middle-east journal of scientific research, 13(1), 114-120. doi: 10.5829/idosi.mejsr.2013.13.1.64121. https://doi.org/10.15244/pjoes/110447. montes, c., acharya, n., hassan, s. m. q., & krupnik, t. j. (2021). intense precipitation events during the monsoon season in bangladesh as captured by satellite-based products. journal of hydrometeorology. https://doi.org/10.1175/jhm-d-20-0287.1 http://www.ijsrp.org/research-paper-1214.php?rp=p363487 https://www.cropj.com/alamgir_5_9_2011_1094_1101.pdf https://www.cropj.com/alamgir_5_9_2011_1094_1101.pdf https://www.researchgate.net/publication/346937518_detection_of_waterlogging_floods_in_bengal_mega-delta_from_people's_perception_underpinned_by_hydrometeorological_dataset https://doi.org/10.1007/s00704-020-03244-x https://asrjetsjournal.org/index.php/american_scientific_journal/article/view/5882 https://asrjetsjournal.org/index.php/american_scientific_journal/article/view/5882 https://doi.org/10.4236/jgis.2016.84045 http://maas.edu.mm/research/admin/pdf/16.%20myo%20myo%20khine%20(297-314).pdf http://maas.edu.mm/research/admin/pdf/16.%20myo%20myo%20khine%20(297-314).pdf https://bu.ac.bd/uploads/buj1v4i1/7.%20illias%20mahmud.pdf. https://www.researchgate.net/profile/samarendra-karmakar/publication/288989212_climatic_feature_of_heavy_rainfall_activities_in_monsoon_season_and_its_socio-economic_impact_in_bangladesh/links/5687fbdd08aebccc4e1550b5/climatic-feature-of-heavy-rainfall-act https://www.researchgate.net/profile/samarendra-karmakar/publication/288989212_climatic_feature_of_heavy_rainfall_activities_in_monsoon_season_and_its_socio-economic_impact_in_bangladesh/links/5687fbdd08aebccc4e1550b5/climatic-feature-of-heavy-rainfall-act https://www.researchgate.net/profile/samarendra-karmakar/publication/288989212_climatic_feature_of_heavy_rainfall_activities_in_monsoon_season_and_its_socio-economic_impact_in_bangladesh/links/5687fbdd08aebccc4e1550b5/climatic-feature-of-heavy-rainfall-act https://doi.org/10.1080/01431169608948714 https://doi.org/10.15244/pjoes/110447 https://doi.org/10.1175/jhm-d-20-0287.1 155 md. naimur rahman & sajjad hossain shozib / geosfera indonesia 6 (2), 2021, 143-156 morales-barquero, l., lyons, m. b., phinn, s. r., & roelfsema, c. m. (2019). trends in remote sensing accuracy assessment approaches in the context of natural resources. remote sensing, 11(19), 2305. https://doi.org/10.3390/rs11192305. özelkan, e. (2020). water body detection analysis using ndwi indices derived from landsat-8 oli. polish journal of environmental studies, 29(2), 1759-1769. https://doi.org/10.15244/pjoes/110447. quan, r.-s., liu, m., lu, m., zhang, l.-j., wang, j.-j., & xu, s.-y. (2010). waterlogging risk assessment based on land use/cover change: a case study in pudong new area, shanghai. environmental earth sciences, 61(6), 1113-1121. https://doi.org/10.1007/s12665-009-0431-8. qureshi, a. s., mccornick, p. g., qadir, m., & aslam, z. (2008). managing salinity and waterlogging in the indus basin of pakistan. agricultural water management, 95(1), 1-10. https://doi.org/10.1016/j.agwat.2007.09.014. rahman, m. s., & islam, a. r. m. t. (2019). are precipitation concentration and intensity changing in bangladesh overtimes? analysis of the possible causes of changes in precipitation systems. science of the total environment, 690, 370-387. https://doi.org/10.1016/j.scitotenv.2019.06.529. romina, p., abeledo, l. g., & miralles, d. j. (2018). physiological traits associated with reductions in grain number in wheat and barley under waterlogging. plant and soil, 429(1-2), 469-481. https://doi.org/10.1007/s11104-018-3708-4. sahu, a. s. (2014). a study on moyna basin water-logged areas (india) using remote sensing and gis methods and their contemporary economic significance. geography journal, 2014, 1–9. https://doi.org/10.1155/2014/401324. sar, n., chatterjee, s., & adhikari, m. d. (2015). integrated remote sensing and gis based spatial modelling through analytical hierarchy process (ahp) for water logging hazard, vulnerability and risk assessment in keleghai river basin, india. modeling earth systems and environment, 1(4), 31. https://doi.org/10.1007/s40808-015-0039-9. shaibur, m. r., shamim, a. h. m., rizvi, m. m., amara, u., & sarwar, s. (2019). local adaptation strategies with waterlogging condition in beel kapalia region, jashore, bangladesh. environmental and biological research, 1(1), 22-31. https://doi.org/10.1155/2014/401324. solaiman, z., colmer, t., loss, s., thomson, b., & siddique, k. (2007). growth responses of cool-season grain legumes to transient waterlogging. australian journal of agricultural research, 58(5), 406-412. https://doi.org/10.1071/ar06330. talukdar, s., ghose, b., salam, r., mahato, s., pham, q. b., linh, n. t. t., . . . avand, m. (2020). flood susceptibility modeling in teesta river basin, bangladesh using novel ensembles of bagging algorithms. stochastic environmental research and risk assessment, 34(12), 2277–2300. https://doi.org/10.1007/s00477-020-01862-5. the daily star (2021). heavy rain disrupts life in dhaka. retrieved from https://www.thedailystar.net/tags/heavy-rain. https://doi.org/10.3390/rs11192305 https://doi.org/10.15244/pjoes/110447 https://doi.org/10.1007/s12665-009-0431-8 https://doi.org/10.1016/j.agwat.2007.09.014 https://doi.org/10.1016/j.scitotenv.2019.06.529 https://doi.org/10.1007/s11104-018-3708-4 https://doi.org/10.1155/2014/401324 https://doi.org/10.1007/s40808-015-0039-9 https://doi.org/10.1155/2014/401324 https://doi.org/10.1071/ar06330 https://doi.org/10.1007/s00477-020-01862-5 https://www.thedailystar.net/tags/heavy-rain 156 md. naimur rahman & sajjad hossain shozib / geosfera indonesia 6 (2), 2021, 143-156 islam, a. r. m. t., rahman, m. s., khatun, r., & hu, z. (2020). spatiotemporal trends in the frequency of daily rainfall in bangladesh during 1975–2017. theoretical and applied climatology, 141(3), 869–887. https://doi.org/10.1007/s00704-020-03244-x. ullah, s., you, q., ullah, w., & ali, a. (2018). observed changes in precipitation in chinapakistan economic corridor during 1980–2016. atmospheric research, 210(c), 1–14. https://doi.org/10.1016/j.atmosres.2018.04.007. yaduvanshi, n., setter, t., sharma, s., singh, k., & kulshreshtha, n. (2012). influence of waterlogging on yield of wheat (triticum aestivum), redox potentials, and concentrations of microelements in different soils in india and australia. soil research, 50(6), 489–499. https://doi.org/10.1071/sr11266. https://doi.org/10.1007/s00704-020-03244-x https://doi.org/10.1016/j.atmosres.2018.04.007 https://doi.org/10.1071/sr11266 210 modeling land use and land cover dynamic using geographic information system and markov-ca millary agung widiawaty1, arif ismail1,2*, moh. dede3, n. nurhanifah1 1 department of geography education, faculty of social sciences education (fpips), universitas pendidikan indonesia, bandung city, west java, 40154, indonesia 2 study program on survey, mapping and geographic information, faculty of social sciences education (fpips),universitas pendidikan indonesia, bandung city, west java, 40154, indonesia 3 master program on environmental science, postgraduate school (sps), universitas padjadjaran, bandung city, west java, 40132, indonesia *corresponding author : arifismail@upi.edu received 27 april 2020/ revised 30 june 2020 / accepted 5 july 2020/ available online 12 july 2020 abstract the need for built-up area increases along with a rise in population growth in many regions. this phenomenon leads to a tremendous change in agricultural land and decrease in the environmental carrying capacity. therefore, this study aims to determine land use and land cover (lulc) dynamics and the drivers used for its modeling in 2030. this is a quantitative study, which uses the dynamic models of geographic information system (gis) and markovca. data were obtained from the cnes-airbus satellite imageries in 2009, 2014, and 2019 by using google earth at east cirebon. the drivers include road density, distance to cbd, total population, distance to settlements, land slope and distance to rivers. the interaction between drivers and lulc change was analyzed using binary logistic regression. the results showed that the rise of built-up area reached 36.4 percent and causes the loss of 0.78 km2 of agricultural land from 2009 to 2019. the lulc simulation in 2030 shows an increase in the built-up area by 82.85 percent with probabilities above 0.6. meanwhile the significant drivers for changes include road density and distance to settlements. in conclusion, efforts to reduce lulc change in agricultural land into built-up area is by re-strengthening spatial planningbased environmental awareness for the community. keywords: built-up area; gis; lulc; markov-ca; spatial modeling geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.5 no. 2 (2020), 210-225, august, 2020 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v5i2.17596 accredited by the ministry of research , technology , and higher education of the republic of indonesia, no. 30/e/kpt/2019. mailto:arifismail@upi.edu mailto:arifismail@upi.edu https://jurnal.unej.ac.id/index.php/geosi https://drive.google.com/file/d/1rsnvas6cuhowhl5bj87cl2l6k5dqz7s6/view 212 millary agung widiawaty et al / geosi vol 5 no 2 (2020) 210-225 1. introduction land is a valuable resource formed from biotic and abiotic components on the earth's surface (asselen & verburg, 2013). its various forms and uses are referred to as land use and land cover (lulc) (aspinal & hill, 2008). land growth rates and human needs have varying patterns, although it is a limited resources– its value typically appreciates over time. it has both direct and indirect impacts on humans which leads to the dynamic phenomenon of lulc, such as the transformation of agricultural land into built-up area (gashaw et al., 2017). this condition is caused by several factors or drivers, from the physical and social environment (kusratmoko et al., 2017). in indonesia, the rate of land conversion follows a linear pattern from 1.8 percent to 2.1 percent (bps, 2013). there is an increase in the demand for built-up areas such as housing, amenities, infrastructure as well as employment in the industrial sector due to the 2030 demographic dividend. this led to the shrinkage of productive-agricultural lands that served as food barns. cirebon is one of the regions which has agricultural comparative-advantage, as well as a similar pattern of lulc conversion (dede et al., 2016; dede et al., 2019). this is evident in the emergence of its regional planning (rtrw) from 2018 to 2038 and regional regulation on sustainable agricultural land (lp2b), these two policies have the directives to protect 45,000 hectares of agricultural land against lulc change. lulc change in the western region of cirebon occurred due to industrialization, while in the eastern part, it is caused by the development of new residential and industrial areas for numerous multinational companies. another region that experiences this change is gebang sub-district. its development is rapidly instigated by the local government because this region has poor economic growth than the western region of cirebon. this actualization was realized by the residential and industrial projects carried out on lands formerly used for agricultural purposes. assuming, the rate of lulc change is not properly controlled, it tends to cause several impacts as well as a decline on environmental carrying capacity (hidajat et al., 2013). the factors that affects this phenomenon is geographically determined through an efficient method referred to as spatial modeling . its dynamic nature is predicted using spatial modeling and geographic information system (gis) subsequently, the use of vector and raster data based on remote sensing imageries is ideal for future purposes (dan-jumbo et al., 2018). an lulc spatial modeling relating to physical and social factors is capable of determining (didactic) and illustrating the dynamic process (heuristic) to produce useful outcomes for the regional development planning (sanders, 2007; kangalawe 211 212 millary agung widiawaty et al / geosi vol 5 no 2 (2020) 210-225 & lyimo, 2010). it is also used to evaluate the changes in probability, the influence of the factors or drivers, and dynamic scenario based on certain trends in space and time (kumar et al., 2015). markov-cellular automata (ca) is a dynamic spatial model composed of cells (pixels or grids), each of which is systematically arranged. it is also robust in predicting the transitions or spatial and temporal dynamics among a number of lulc types…. 2014). this model is a computational method for determining dynamic systematic changes that depend on certain rules developed temporally (liu, 2012). it functions in accordance with the principle of game play, it is sensitive to cell size, and neighborhood configuration or similar to three or more existent parcels (moreno, 2008). markov-ca, when compared with other dynamic models has advantages such as the ability of individuals to boost information that has under the regular principles, regulates their evaluation, and analysis of the spatial (space) characteristics, used to easily predict land use in the future (gambo et al., 2018). knowledge of existing lulc changes and the probability of its dynamics in the future is important for regional development, particularly in rural areas proposed as growth centers such as gebang district, and cirebon regency. previous studies generally examined the lulc changes in critical watershed, peri-urban, metropolitan, and megapolitan regions (lahti, 2008; chavula et al., 2011; li et al., 2019). furthermore, the studies carried out in rural areas, primarily focuses on the use of land for agricultural purposes and forestry (sodikin et al., 2018; voight et al., 2019). according to previous studies, its factors or drivers tend to have an effect on the biogeophysical aspects rather than the regional socio -economic conditions. therefore, efforts to examine lulc changes in rural areas with potentially significant landscapes are essential for adaptive and sustainable regional development policies. this study aims to determine the dynamics of lulc in gebang district representing the eastern cirebon and the future application of gis and markov-ca models. 2. methods 2.1 study area this research was carried out at gebang sub-district, east cirebon regency, west java. this area is situated between cirebon, kuningan and brebes regency. it has a tropical climate characterized by an average temperature of 32o celsius and annual rainfall of approximately 2000 to 2500 mm. gebang has an altitude of 0 to 37 m above sea level and the region is suitable for the cultivation of rice, pulses and sugarcane, however it is quite susceptible to flood and tidal rising. this study applied saturated sampling in 14 villages 212 millary agung widiawaty et al / geosi vol 5 no 2 (2020) 210-225 (figure 1). subsequently, lulc dynamic model is an input for environmental conservation as well as efforts to protect productive agricultural land. 2.2 data acquisitions basic information on lulc was obtained using the 2009 cnes-airbus imagery which had a spatial resolution of 0.96 meters. the analysis of land changes were initiated based on a temporal span of 10 years which was due to the independent implementation of development policies in the region – in the early 2000s, gebang was separated from babakan. the second temporal (time) data was obtained with the 2014 cnes-airbus imagery. meanwhile, the first law of geography refers to the dynamics of lulc's spatial modeling which stated that everything is related, however those that are closer are more influential than distant things (sui, 2004; de smith et al., 2007; foresman & luscombe, 2017). consequently, all spatial phenomena are formed due to reciprocal relationships with their neighboring environment, which leads to geographical closeness that offers stronger and more influential interactions. this is common in cross-sectional phenomena such as land use, therefore the markov-ca, is a suitable mathematical model (hamad, et al., 2018; hua, 2017). figure 1. study area this study utilized primary data obtained from field surveys carried out as part of testing land use in 2019, however secondary data was derived from reliable sources, namely 213 214 millary agung widiawaty et al / geosi vol 5 no 2 (2020) 210-225 scientific articles, official reports of government and non-governmental institutions (table 1). these data are validated according to geospatial criteria in order to enable lulc dynamic spatial modeling. table 1. data acquisition and research variables variable or driver data data acquisition land slope (x1) raster aster dem (2019) distance to rivers (x2) vector field survey (2019) and buffering hot-osm bnpb data (2019) distance to cbd (x3) vector buffering based on field survey (2019) total population (x4) atribut indonesian statistical agency (bps) (2019) road density (x5) vector big tanah air-geoportal (2019) distance to settlements (x6) vector buffering based on visual-supervised classification of cnes-airbus (2019) land use and land cover (y) vector and raster visual-supervised classification of cnes-airbus imageries (2019) and field survey (2019) 2.3 data analysis this research applied a quantitative approach for making interpretation and drawing inferences from changes in the dynamic system which occurs due to its drivers and the lulc predictions by the markov-ca model. supposing the outcome is combined with nonparametric statistical analysis, the determinants or drivers influencing this phenomenon are discerned (quan et al., 2006; deng et al., 2009). therefore, the results from markov-ca were combined with the logistic regression method to obtain the probability value in the modeling of lulc in gebang (equation 1). logistic regression is defined as a type of non parametric statistics, which involves the interaction between variables relating to an actual situation in the absence of classical assumption test. the modelsproduce potential lulc dynamics in the future. the probability of spatial dynamics is determined by the transformation of standardized z values (hosmer, 2013). through this model, the intervention of independent variables that are highly significant pr oduces several scenarios of lulc probabilities. ln ( p 1-p ) = α + β1 x1 +β2 x2 + …. + βn xn ( (1) where ln is the natural logaritmic, p probability value, α regression constant, and β predictor coefficient. the results from the validation of spatial modeling were obtained using data from ground truth which involves 30 lulc samples from all villages in gebang sub-district. this 215 millary agung widiawaty et al / geosi vol 5 no 2 (2020) 210-225 effort is evident in the overall accuracy and kappa values (as shown in equation 2 and 3) (widiawaty et al., 2018). overall accuracy = l1 + l2 + …. + ln n ( (2) overall kappa = oa ea 1 ea ( (3) where l is lulc types, n total samples, oa observed, and ea expected agreement. 3. results and discussion the analysis of lulc dynamics started in 2009 because the study area showed the independent implementation of development policies after it was separated from babakan sub-district in the early 2000s. during this period lulc was dominated by agricultural land and salt-fisheries with an area of approximately 29.11 km2 (82.38 percent), other large proportion consist of built-up areas (2.93 km2) and plantations (2.60 km2). in 2014, the builtup area gained a significant increase of approximately 0.93 km2, five years later. however, various conditions caused a decline at the plantations and agricultural lands to relatively 0.26 – 0.58 km2 (as shown in figure 2). in accordance with the aquacultural sector, there was a decline in areas utilized as salt-fisheries and they were transformed into mangrove forests due to lack of management. it is assumed that the prediction of lulc information during the final periods are based on the interpretation and classification of imageries, obtained in 2019 and 2030 using gis and markov-ca model. the model used a redundant temporal dynamics with pixel resolution 5 m x 5 according to the geospatial regulation in indonesia (law 4/2011 of geospatial information). the lulc model has an overall accuracy of 93.33 percent and kappa of 0.92, therefore it is valid and needs to be recommended for future purposes. the high-level of accuracy is considered prevalent due to the detection of lulc using high satellite imagery resolution with an accuracy of relatively 0.80 (ustuner et al., 2017). the lulc model in 2019 showed several changes in built-up areas, furthermore its increase caused a decline in agricultural lands, plantation, etc (figure 3). the occurrence of accretion led to the development of mangrove vegetation of approximately 0.02 km2. sediment materials from ci beres and ci sanggarung accumulated in the shoreline of gebang. in 2030, gebang sub-district is expected to be highly-dynamic because the built-up areas was approximately 20.67 percent, tend to increase to 3.99 km2 due to the function of non-vegetated land and plantations with a probability of 0.43 – 0.45. changes in lulc were 216 millary agung widiawaty et al / geosi vol 5 no 2 (2020) 210-225 also detected in agricultural land and shrubs with a probability of relatively 0.10 as shown in table 2. the direction of the dynamics in this region starts with the exhaustion of agricultural land which is converted to non-vegetated land till it is covered with marshes and woody plants. initially, it was made up of agricultural land which gradually became compact and used to build settlements as well as other infrastructures to support human needs. this is common in various parts of the world to prevent subsidence thereby resulting in the conversion and utilization of inappropriate human activities to manage the environment (minderhoud et al., 2018). therefore, the agricultural land is directly converted to built-up areas. figure 2 shows that agricultural land decrease every time. figure 2. lulc change in gebang and prediction in the future table 2. lulc change probabilities lulc type probability wb ma pt nv ba al mr sf water bodies (wb) 0.322 0.049 0.171 0.002 0.114 0.089 0.023 0.231 mangroves (ma) 0.182 0.029 0.047 0.003 0.038 0.029 0.008 0.666 plantations (pt) 0.029 0.002 0.346 0.001 0.447 0.167 0.002 0.007 non-vegetated (nv) 0.015 0.005 0.042 0.009 0.437 0.162 0.001 0.331 built-up area (ba) 0.021 0.001 0.090 0.000 0.870 0.015 0.001 0.002 agricultural land (al) 0.003 0.000 0.063 0.009 0.122 0.789 0.000 0.014 marsh (mr) 0.042 0.007 0.158 0.002 0.126 0.149 0.078 0.439 salt area & fisheries (sf) 0.047 0.022 0.011 0.007 0.053 0.054 0.001 0.804 mean 0.083 0.014 0.116 0.004 0.276 0.181 0.014 0.312 210 millary agung widiawaty et al / geosi vol 5 no 2 (2020) 210-225 lulc transition shows that human intervention in agricultural activities has the tendency to change the land into a built-up area. this condition is driven by lack and the pragmatic attitude of young people to become farmers – due to the fact that poverty aided in accelerating the rate of land conversion in the cirebon regency, particularly in gebang district. the results from the gain and loss analysis show that the developed area was approximately 4.38 km2, while the agricultural land was reduced to 4.22 km2 as shown in table 3. the lulc dynamics shows that a significant interaction exists between the decline in agricultural land and increase of built-up area. this pattern leads to food inequality because the human population continues to grow while there is a decline in agricultural lands, particularly in developing countries due to modernization and industrialization (ouedraogo et al., 2010; mhawish & saba, 2016). figure 3 shows the expansion of built-up area in previous periods tends to be close to the road. figure 3. lulc dynamic map of gebang 3.1 driven factors of lulc change lulc change in a dynamic system occurs due to various factors. the ca model produces predictions which combines with non-parametric statistical analysis useful in 217 218 millary agung widiawaty et al / geosi vol 5 no 2 (2020) 210-225 determining the various factors that influences this phenomenon referred to as drivers (kamwi et al., 2018; munthali et al., 2019). therefore, the lulc modeling in gebang subdistrict is combined with the markov-ca logistic regression methods to obtain the probability value of the dynamics. the testing involved 6 (six) factors or drivers known as independent variables namely land slope, distance to rivers, distance to cbd, population, road density, and distance to the built-up area which were analyzed and reclassified as shown in figure 4. lulc change is a dependent variable which consists of both changed and nonchanged lands. figure 4. drivers of lulc changes 219 millary agung widiawaty et al / geosi vol 5 no 2 (2020) 210-225 table 3. gain and loss all types of lulc in gebang lulc type area (km 2 ) gain & loss (%) 2009 2014 2019 2030 2009 2014 2019 2030 water bodies (wb) 0.52 0.51 0.49 0.50 -0.89 -3.93 2.10 mangroves (ma) 0.05 0.12 0.10 0.04 129.5 -18.02 -62.78 plantations (pt) 2.60 2.34 2.41 2.19 -9.96 3.01 -8.99 non-vegetated (nv) 0.08 0.13 0.11 0.06 74.27 -16.83 -43.62 built-up area (ba) 2.93 3.86 3.99 7.30 31.79 3.52 82.94 agricultural land (al) 20.6 20.0 19.9 16.8 -2.78 -0.92 -15.36 marsh (mr) 0.05 0.04 0.03 0.03 -25.46 -14.99 -3.59 salt area & fisheries (sf) 8.49 8.29 8.34 8.41 -2.36 0.54 0.86 table 4. interaction between drivers and lulc variable or driver β exp(b) sig. status land slope (x1) 0.021 1.021 0.746 not significant distance to rivers (x2) 0.032 1.033 0.442 not significant distance to cbd (x3) -0.090 0.914 0.254 not significant total population (x4) -0.061 0.941 0.415 not significant road density (x5) 0.228 1.256 0.001 significant distance to settlements (x6) 1.776 5.907 0.000 significant constant -8.647 0.000 0.000 significant table 5. lulc dynamic model validity model accuracy and drivers influence accuracy (percent) nagelkerke test (r and r 2 ) significance without drivers using drivers p-value α 50.2 66.0 0.493 and 0.243 0.00 0.05 goodness of fit (gof) hosmer-lameshow chi-square value chi-square table dof p-vaue α status 10.61 15.51 8 0.225 0.05 fit relative operative characteristics (roc) 0.73 ln ( p 1-p ) = 8.65 + 0.02 x1+ 0.03 x2 0.09 x30.06 x4 + 0.23 x5 + 1.18 x6 (4) the result from logistic regression test implies that road density and distance to built up area have a significant influence of approximately 95 percent confidence level (table 4). this condition shows that the pattern of lulc changes tends to be close to the existing builtup area which has quality accessibility (saputra & lee, 2019). in addition, six drivers simultaneously have a significant influence on lulc change, the r -value obtained from the 220 millary agung widiawaty et al / geosi vol 5 no 2 (2020) 210-225 nagelkerke test is0.493, and an increase was detected in the value of markov-ca based on gof and roc (as shown in table 5). however, lulc changes also occur without influencing the drivers. this is evident in the 0.757 value of the epsilon which shows that other factors such as socio-economic conditions and political policies also influences the lulc preferences (yirsaw et al., 2017). the interaction value between the drivers and lulc change in the regression model is shown in equation 4. the statistical results also known as the drivers of socio-economic aspects are more influential than the biogeophysical aspects in gebang. these are certainly different from previous studies which stated that slope and distant water bodies are significant drivers (hassen & assen, 2017; dibaba et al., 2020). this shows that abrupt knowledge of the socioeconomic condition is necessary in the analysis of lulc change, although the nature of these drivers tends to be dynamic and difficult because they are the two main causes of urbanization – in the context of the development of rural and urban landscape (han et al., 2015). 3.2 probability lulc in 2030 the values of the input independent variable (drivers) stated in equation 4 predicts the probability of lulc change in 2030. out of the six drivers, four of them are constant namely slope, distances to the river, built-up area, and cbd. therefore, the spatial probability of lulc in gebang is only affected by two dynamic drivers namely population number and road density which are both significant variables. population number in 2030 is obtained from the prediction of the population growth from 2009 to 2019. gebang sub -district has a population growth of 1.42 percent per year, therefore in 2030 it is predicted to be 67,449 people (approximately 10.77 percent). the increasing road density in 2030 is derived from the national average road development which is relatively 0.12 percent per year (istiono, 2014). the results from processing and inputting data for the drivers into a logistic regression equation produced a probability scenario of lulc change as shown in figure 5. this pattern of change is similar to the research carried out by mienmany (2018) which predicts that almost all types of lulc have a potential change towards the built-up area. in 2030, the probability of lulc change is predicted to be high in four villages – gebang kulon, gebang ilir, gebang mekar, and gebang udik. these areas are close to the gebang cbd and have high density, due to the influence of national arterial roads (pantura). its existence offers a variety of socio-economic benefits for the population due to the role of 221 millary agung widiawaty et al / geosi vol 5 no 2 (2020) 210-225 interregional interaction, and the presence of built-up areas (mcandrews et al., 2017; yesuph & dagnew, 2019). the total area of 0.55 km2 has a probability of approximately 0.4. this value is smaller when compared to the land probability of 0.001 – 0.1 with an area of 3.06 km2, irrespective of the changes. figure 5. a) pattern of lulc change transition and b) probability change of lulc gebang in 2030 4. conclusion the integration of gis and markov-ca led to the emergence of a dynamic lulc model and information on various factors which influenced its changes in the gebang subdistrict. this research discovered that from 2009 to 2030 there tends to be an increase in built-up area accompanied by a decline in agricultural land and plantations. the predictions of 2030 also showed that the developed area was expanded to appr oximately 20.67 percent, while the largest land loss of relatively 18.5 percent occurred in agricultural land. two drivers that have significant influence on lulc change is road density and distance to built 222 millary agung widiawaty et al / geosi vol 5 no 2 (2020) 210-225 up area. in addition, the total chances of lulc occurrence in this region was approximately 4.31 km2. conflict of interest the authors declare that there is no conflict of interest with any financial, personal, or other relationships with other people or organizations related to the material discussed in the article. acknowledgements this research is part of spatial dynamic project which were supported by fpips univesitas pendidikan indonesia (upi). the authors are grateful to dr. iwan setiawan (head of spig program, department of geography education, fpips-upi) and nurul huda (math teacher of sma negeri 1 babakan, cirebon regency) for their various contributions. references aspinall, r. j. & hill, m. c. (2008). land use change, science, policy and management. new york: taylor & francis. asselen, s. & verburg, p. h. (2013). land cover change or landuse intensification, simulating land system change with a global scale land change model. global change biology, 19(12): 3648-3667. bps. (2013). proyeksi penduduk indonesia 2010-2035. jakarta: bps. chavula, g., brezonik, p. & bauer, m. (2011). land use and land cover change (lulc) in the lake malawi drainage basin 1982-2005. international journal of geosciences, 2 (2): 172-178. dan-jumbo, n. g., metzger, m. j. & clark, a. p. (2018). urban land-use dynamics in the niger delta: the case of greater port harcourt watershed. urban science, 2(4): 1-24. de smith, m. j. (2007). geospatial analysis: a comprehensive guide to principles, te chniques and software tools. leicester: troubador publishing. dede, m., sahidin, r. b. s., yutika, m. & ramadhan (2016). analisis potensi perekonomian sektor pertanian, kehutanan, dan perikanan serta pertambangan dan penggalian di pantura jawa barat. prosiding seminar nasional epicentrum geografi, 5.5: 100-108. dede, m., widiawaty, m. a., pramulatsih, g. p., ismali, a., ati, a. & murtianto, h. (2019). integration of participatory mapping, crowdsourcing and geographic information system in flood disaster management (case study ciledug lor, cirebon). journal of information technology and its utilization, 2(2): 44-47. 223 millary agung widiawaty et al / geosi vol 5 no 2 (2020) 210-225 deng, j. s., wang, k., hong, y. and jia, g. q. (2009). spatio-temporal dynamics and evolution of land use change and landscape pattern in response to rapid urbanization. landscape and urban planning, 92(3): 187-198. dibaba, w. t., demissie, t. a., & miegel, k. (2020). drivers and implications of land use/land cover dynamics in finchaa catchment, northwestern ethiopia. land, 9(4) doi:10.3390/land9040113. foresman, t., & luscombe, r. (2017). the second law of geography for a spatially enabled economy. international journal of digital earth, 10(10), 979-995. doi:10.1080/17538947.2016.1275830. gambo, j., shafri, h. z. m., shaharum, n. s., abidin, f. a. & rahman, m. t. (2018). monitoring and predicting land use-land cover (lulc) changes within around krau wildlife reserve (kwr) protected area in malaysia using multi-temporal landsat data. geoplanning: journal of geomatics and planning, 5(1): 17-34. gashaw, t. (2017). evaluation and prediction of land use/land cover changes in the andassa watershed, blue nile basin, ethiopia. environmental systems research, 6(17): 1-15. hamad, r., balzter, h., & kolo, k. (2018). predicting land use/land cover changes using a ca-markov model under two different scenarios. sustainability (switzerland), 10(10) doi:10.3390/su10103421. han, h., yang, c., & song, j. (2015). scenario simulation and the prediction of land use and land cover change in beijing, china. sustainability (switzerland), 7(4), 4260-4279. doi:10.3390/su7044260. hassen, e. a. & assen, m. (2017). land use/cover dynamics and its drivers in gelda catchment, lake tana watershed, ethiopia. environ. syst. res., 6 (4): 1-13. hidajat, m., sitorus, s. r. p. & rustiadi, e. (2013). urban sprawl effect on settlement areas in urban fringe of metropolitan area. journal of environment and earth science, 12(3): 172-179. hosmer, d. (2013). applied logistic regression. new jersey: john wiley & sons. hua, a. k. (2017). application of ca-markov model and land use/land cover changes in malacca river watershed, malaysia. applied ecology and environmental research 15(4): 605-622. istiono. (2014). perubahan perilaku pengguna jalan yang berkeselamatan (safer road users) guna menekan tingkat kecelakaan. jakarta: the indonesian center for police and security studies. kamwi, j. m., cho, m. a., kaetsch, c., manda, s. o., graz, f. p. & chirwa, p. w. (2018). assessing the spatial drivers of land use and land cover change in the protected and communal areas of the zambezi region, namibia. land, 7(131): 1-13. 224 millary agung widiawaty et al / geosi vol 5 no 2 (2020) 210-225 kangalawe, r. y. m & lyimo, j. g. (2010). population dynamics, rural livelihoods and environmental degradation: some experiences from tanzania. environment, development and sustainability, 12(6): 985-997. kumar, k. s., valasala, n. v. a., subrahmanyam, j. v. v., mallampati, m., shaik, k. & ekkirala, p. (2015). prediction of future land use land cover changes of vijayawada city using remote sensing and gis. international journal of innovative research in advanced engineering, 3(2): 91-97. kusratmoko, e. (2017). modelling land use/cover changes with markov-cellular automata in komering watershed, south sumatera. iop conf. series: earth and environmental science, 54(17): 5-8. lahti, j. (2008). modelling urban growth using cellular automata: a case study of sydney, australia. master thesis. international institute for geo-information science and earth observation, enschede, the netherlands. li, s., yang, h., lacayo, m., liu, j., & lei, g. (2018). impacts of land-use and land-cover changes on water yield: a case study in jing-jin-ji, china. sustainability (switzerland), 10(4) doi:10.3390/su10040960. liu, y. (2012). modelling sustainable urban growth in a rapidly urbanising region using a fuzzy constrained cellular automata approach. international journal of geographical information science, 26(1): 151-167. mcandrews, c., pollack, k. m., berrigan, d., dannenberg, a. l. & christopher, j. (2017). understanding and improving arterial roads to support public health and transportation goals. american journal of public health, 107(8): 1278-1282. mhawish, y. m. & saba, m. (2016). impact of population growth on land use changes in wadi ziqlab of jordan between 1952 and 2008. international journal of applied sociology, 6(1): 7-14. mienmany, b. (2018). analysis of land use and land cover changes and the driving forces:a case study in kaysone phomvihan district, laos. master thesis. faculty of arts, universidade do porto, portugal. minderhoud, p. s. j., coumou, l., erban, l. e., middelkoop, h., stouthamer, e. and addink, e. a. (2018). the relation between land use and subsidence in the vietnamese mekong delta. sci. total environ., 634: 715–726. moreno, n. l. (2008). a vector-based geographical cellular automata model to mitigate scale sensitivity and to allow objects geometric transformation. phd thesis. university of calgary. munthali, m. g., davis, n., adeola, a. m., botai, j. o., kamwi, j. m., chisale, h. l. w., & orimoogunje, o. o. i. (2019). local perception of drivers of land-use and landcover change dynamics across dedza district, central malawi region. sustainability (switzerland), 11(3) doi:10.3390/su11030832. 225 millary agung widiawaty et al / geosi vol 5 no 2 (2020) 210-225 ouedraogo, i., tigabu, m., savadogo, p., compaoré, h., oden, p. c. & ouadba, j.m. (2010). land cover change and its relation with population dynamics in burkina faso, west africa. land degradation & environment, 21(5): 453-462. quan, b., chen, j. f., qiu, h. l., romkens, m. j. m., yang, x. q., jiang, s. f. & li, b. c. (2006). spatial-temporal pattern and driving forces of land use changes in xiamen. pedosphere, 16(4): 477-488. sanders, l. (2007). model in spatial analysis. london: iste, ltd. saputra, m. h., & lee, h. s. (2019). prediction of land use and land cover changes for north sumatra, indonesia, using an artificial-neural-network-based cellular automaton. sustainability (switzerland), 11(11) doi:10.3390/su11113024. sodikin, sitorus s. r. p., prasetyo l. b. & kusmana c. (2017). spatial analysis of mangrove deforestation and mangrove rehabilitation directive in indramayu regency, west java, indonesia. aacl bioflux, 10(6):1654-1662. sui, d. z. (2004). tobler’s first law of geography: a big idea for small world?. annals of the association of american geographers, 94(2): 269-277. ustuner, m., sanli, f. b. & dixon, b. (2017). application of support vector machines for landuse classification using high-resolution rapideye images: a sensitivity analysis. european journal of remote sensing, 48(1): 403-422. voight, c., hernandez-aguilar, k., garcia, c., & gutierrez, s. (2019). predictive modeling of future forest cover change patterns in southern belize. remote sensing, 11(7) doi:10.3390/rs11070823. widiawaty, m. a., dede, m. & ismail, a. (2018). analisis tipologi urban sprawl di kota bandung menggunakan sistem informasi geografis. seminar nasional geomatika, 3:547-554. yesuph, a.y. & dagnew, a.b. (2019). land use/cover spatiotemporal dynamics, driving forces and implications at the beshillo catchment of the blue nile basin, north eastern highlands of ethiopia. environ. syst. res., 8(21): 1-30. yirsaw, e., wu, w., shi, x., temesgen, h., & bekele, b. (2017). land use/land cover change modeling and the prediction of subsequent changes in ecosystem service values in a coastal area of china, the su-xi-chang region. sustainability (switzerland), 9(7) doi:10.3390/su9071204. geosfera indonesia published by: department of geography education university of jember e-issn 2614-8528 p-issn 2598-9723 geos. ind. vol. 6 no. 2, august 2021 available online since 17 august 2021 at : https://jurnal.unej.ac.id/index.php/geosi geosfera indonesia published by: department of geography education university of jember e-issn 2614-8528 p-issn 2598-9723 geos. ind. vol. 6 no. 2, august 2021 available online since 17 august 2021 at : https://jurnal.unej.ac.id/index.php/geosi geosfera indonesia published by: department of geography education university of jember e-issn 2614-8528 p-issn 2598-9723 geos. ind. vol. 6 no. 2, august 2021 available online since 17 august 2021 at : https://jurnal.unej.ac.id/index.php/geosi geosfera indonesia, vol. 6 no. 2 (2021) accredited (sinta 2) by the ministry of research and technology of the republic of indonesia (ristekbrin), no. 200/m/kpt/2020 . editorial team editor in chief fahmi arif kurnianto (scopus id: 57208473928) department of geography education, university of jember, indonesia advisory international editorial boards mihai ciprian margarint (scopus id : 36698019400) department of geography, alexandru ioan cuza university of iasi, romania fahrudi ahwan ikhsan (scopus id : 57208469257) department of geography education, university of jember, indonesia mustafa ustuner (scopus id : 56246446800) department of geomatics engineering, yildiz technical university, turkey bashkim idrizi (scopus id : 55937683800) department of geodesy, university "mother teresa" -skopje, macedonia guillermo hector re (scopus id : 7102894803) department of geology, universidad de buenos aires, buenos aires, argentina laras tursilowati (scopus id : 55317967300) indonesian national institute of aeronautics and space (lapan), indonesia m. asyroful mujib (scopus id : 57217104177) department of geography education, university of jember, indonesia lyubka pashova (scopus id : 6506546577) national institute of geophysics, geodesy and geography, bulgarian academy of sciencesdisabled, sofia, bulgaria mohmadisa hashim (scopus id : 55214571400) department of geography & environment, universiti pendidikan sultan idris, malaysia layout editors yucha risdarani (department of geography education, university of jember, indonesia) m. mitasari (department of geography education, university of jember, indonesia) giofani ginolla ardiyanto (department of geography education, university of jember, indonesia) copyright (c) 2021 geosfera indonesia and department of geography education, university of jember focus and scope geosfera indonesia is a journal publishes original research, review, and short communication (written by researchers, academicians, professional, and practitioners from all over the world) which utilizes geographic and environment approaches (human, physical landscape, naturesociety and gis) to resolve human-environment interaction problems that have a spatial dimension. moreover, geosfera indonesia also committed to enhance and share original research, review, and short communication (written by researchers, academicians, professional, and practitioners from all over the world) on geography education and environmental education. our journal's scope includes : 1. geography education 2. physical geography 3. human geography 4. geographic information system (gis) 5. remote sensing 6. environmental science 7. environmental education 8. disaster risk reduction publication information geosfera indonesia (geos. ind.) : | issn: 2598-9723 (print)| issn: 2614-8528 (online) is an international open access and peer-reviewed journal, published by department of geography education, university of jember, indonesia. its published three times a year in april, august, and december. geosfera indonesia is accredited (sinta 2) by the ministry of research and technology of the republic of indonesia (ristekbrin), no. 200/m/kpt/2020. this journal has been covered by following indexing and abstracting services: (1) cabi : cab abstracts ; (2) directory of open access journal (doaj); (3) ebsco; (4) google scholar (5) one search (national library of republic of indonesia), (6) web of science. secretariat of geosfera indonesia department of geography education, university of jember, fkip building, jl. kalimantan 37, jember, east java, 68121, indonesia. telp. (0331) 334988 / 330738 email : geografi.fkip@unej.ac.id website : https://jurnal.unej.ac.id/index.php/geosi copyright (c) 2021 geosfera indonesia and department of geography education, university of jember table of contents flash flood susceptibility mapping at andungbiru watershed, east java using ahp-information weighted method 127-142 devi ratna handini, entin hidayah, gusfan halik seasonal variability of waterlogging in rangpur city corporation using gis and remote sensing techniques 143-156 md. naimur rahman, sajjad hossain shozib potential utilization analysis of river waste in jakarta, indonesia 157-172 rahajeng hasna safira, mega mutiara sari, suprihanto notodarmojo, takanobu inoue, regil kentaurus harryes mapping of soil quality index (sqi) for paddy fields using sentinel-2 imagery, laboratory analysis, and principal component analysis 173-188 putri tunjung sari, indarto indarto, marga mandala, bowo eko cahyono spatial database designing for environmental monitoring and decision making in mitrovica region, the republic of kosovo 189-204 bashkim idrizi, edon maliqi, lyubka pashova 205-221 analysis on factors influencing geography teachers’ ability in constructing high-order thinking skills (hots) assessment instrument suhendro suhendro, dede sugandi, mamat ruhimat the influence of soil conditioning on soil infiltration rate in urban facilities searphin nugroho, wahyono hadi 222-240 copyright (c) 2021 geosfera indonesia and department of geography education, university of jember cover geosfera 62.pdf (p.1) editor.pdf (p.2) focus and scope agusutus1.pdf (p.3-4) 173 research article mapping of soil quality index (sqi) for paddy fields using sentinel-2 imagery, laboratory analysis, and principal component analysis putri tunjung sari1,*, indarto indarto1, marga mandala1, bowo eko cahyono2 1department of natural resources and environmental management, university of jember, jl. kalimantan no. 37 jember, 68121, indonesia 2faculty of mathematics and natural sciences, university of jember, jl. kalimantan no. 37 jember, 68121, indonesia received 2 june 2021/revised 15 july 2021/accepted 26 july 2021/published 17 august 2021 abstract the use of intensive chemical inputs causes lower availability of nutrients, organic matter, cation exchange capacity, and soil degradation.therefore, this study aims to assess the soil quality index (sqi) for paddy fields in jember, east java, indonesia. input data for this study consist of land cover (interpreted from the sentinel-2 image), soil type, and slope maps. furthermore, the procedure to calculate soil quality index (sqi) include (1) spatial analysis to create the land unit, (2) preparation of soil sampling, (3) soil chemical analysis, (4) principal component analysis (pca), and (5) reclassifying soil quality index (sqi). the pca results showed that three variables i.e., % sand, totalp, and % silt were strongly correlated to sqi, while three classes namely very low, low, and medium of sqi were sufficiently used to describe the spatial variability of the paddy field. furthermore, approximately 41.14% of the paddy field area were classed as very low while 52.23%, and 6.63% were categorized as low and medium sqi respectively. based on the results, about 93.37% of paddy fields in jember regency still require improvement in soil quality via the addition of ameliorants such as organic fertilizers to increase quality and productivity. this application needs to focus on areas with very low-low quality hence, the quality increased to the medium category. keywords: mapping; soil quality index (sqi); pca; paddy field 1. introduction the increasing population and food demand have forced farmers to intensify and extend agricultural land to improve productivity (ren et al., 2020). agricultural intensification is an activity that aims to optimize agrarian land by providing additional inputs to increase productivity (xie et al., 2019). meanwhile, extensification involves expanding agricultural land and minimizing external inputs (van grinsven et al., 2015). the use of intensive chemical inputs such as fertilizers and pesticides indicates agricultural intensification activities. however, most farmers do not understand the concept of sustainable agriculture (johannes et al., 2019;terano et al., 2015). *corresponding author. mmm email address: putritunjung36@gmail.com (putri tunjung sari) geosfera indonesia vol. 6 no. 2, august 2021, 173-188 p-issn 2598-9723, e-issn 2614-8528 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v6i2.24506 *corresponding author. mmm email address: putritunjung36@gmail.com (putri tunjung sari) mailto:putritunjung36@gmail.com mailto:putritunjung36@gmail.com 174 putri tunjung sari et al. / geosfera indonesia 6 (2), 2021, 173-188 the continuous use of chemical fertilizers and pesticides has negative impacts on the soil (li et al., 2018). a previous study stated that fertilizer and pesticide residues settle in the soil thereby increasing its acidity (asvini & jithesh, 2018). other impacts observed include lower availability of nutrients, organic matter, and cation exchange capacity (hung et al., 2019; maas et al., 2017). agricultural extensification is usually conducted by land conversion and forest clearing. mohawesh et al. (2015) stated that changes in land-use affect soil quality, while pierzynski et al. (2005) defined soil quality as multicriteria analysis results of chemical, physical and biological properties. furthermore, the characteristics of good soil usually comprise (1) good drainage, (2) good water holding capacity (whc), (3) less erosion, and (4) high nutrient content (seifu & elias, 2018). good quality soil supports optimal plant productivity. meanwhile, soil quality assessments are used to identify, evaluate and determine the appropriate technology for land management and sustainability (roy et al., 2015). rice is widely known as the principal food of the indonesians, therefore, the presence of paddy fields is essential to support agricultural land and fulfill food demand. generally, farmers overuse fertilizers and pesticides, which in turn decrease the land quality. moreover, the input cost of chemical fertilizers and pesticides is expensive compared to the benefit in the form of increase in production (xie et al., 2019). this condition has also been exacerbated by the increased price of chemical fertilizers in the market, hence, farmers spend much money for less productive results. the benefits of calculating sqi include (1) increase farmers' awareness of land mismanagement, (2) mapping complex land variability, and (3) as a guide for sustainable management plan (ren et al., 2020; lin & fukushima, 2016). previous studies only referred to one of the soil's chemical, physical or biological properties to determine sqi (supriyadi et al., 2019; supriyadi et al., 2018). however, this study combines the three parameters to categorize the soil quality (bahnemiri et al., 2019). soil quality analysis based on remote sensing is needed to assess land variability (reddy et al., 2020). meanwhile, remote sensing technology is commonly used to classify land, based on several criteria with high accuracy (hore et al., 2020). the combination of remote sensing and principal component analysis (pca) is effective in assessing soil quality. the pca method is used for data reduction and selection of the primary indicator that best represents the analysis and the results are presented in the form of a minimum data set (mds). furthermore, the mds component reduces the burden of indicators in the sqi calculation model and prevents data redundancies (mukherjee & lal, 2014). 175 putri tunjung sari et al. / geosfera indonesia 6 (2), 2021, 173-188 sqi was more interpolated using the inverse distance weighting (idw) method which predicts value base on the distance between the data point and the expected location. the expected value is calculated as the number of measured data points located in a specific search environment on the predicted site (bofana & costa, 2017). abdel rahman et al. (2021) stated that the idw technique is the most commonly used method to predict soil properties. only a few studies focused on assessing soil quality based on one soil characteristic. also, there are limited studies on the physical, chemical, or biological properties only. therefore, this study aims to assess soil quality based on the physical, chemical, and biological properties by combining spatial analysis. 2. methods this study was conducted from december 2020 to april 2021, and the study area covers all paddy fields in jember regency, east java, indonesia (figure. 1). figure 1. study area and classified land cover map (2019) 176 putri tunjung sari et al. / geosfera indonesia 6 (2), 2021, 173-188 2.1 input data and tool used the three maps (table 1) were used as input data for this study. table 1. research materials material sources land cover map sentinel 2a satellite image data processing (usgs, 2019) soil type map (balai penelitian tanah, 2015) slope map derived from demnas (big, 2019) the tools used in this study consist of soil sampling and laboratory analysis equipment, as well as software for processing. soil sampling equipment consists of a soil drill, shovel, tape measure, and plastic clips, while the laboratory equipment includes atomic absorption spectrophotometer (aas), ph meter, and oven (table 2). the data obtain were analyzed using multispect, gis software, and statistical tools. table 2. list of tools used tool specification and function soil drill to take soil samples shovel to take soil samples aas soil potassium analysis musltispec land cover analysis q-gis soil quality index (sqi) calculations source: (supriyadi et al., 2018) 2.2 research procedure the research procedure consists of (1) determination of land unit, (2) soil sampling, (3) laboratory analysis, (4) principal component analysis (pca), (5) scoring and classification, and (6) assessment of soil quality index (sqi). 2.2.1 land unit and soil sampling the number of the land unit was determined by overlaying and intersecting three input maps, i.e., land cover, soil type, and slope maps, as illustrated in figure 2. first, the land cover map was classified into two namely paddy fields and non-paddy fields, then, the paddy field was converted from raster to polygon vector layer. furthermore, the soil type and slope map were clipped with polygon paddy field maps. the two maps results are united to create a land unit map. 177 putri tunjung sari et al. / geosfera indonesia 6 (2), 2021, 173-188 figure 2. procedure to determine the land unit and soil sampling the soil samples were collected from each land unit map, while four samples for each land unit were then compiled using the soil drill method. furthermore, each land unit was divided into four regions, and sampling was carried out in each area. table 3 shows the 24 samples locations,the samples for each class were then mixed and compiled. figure 3 shows the different soil color photographs taken from (9) nine locations. 178 putri tunjung sari et al. / geosfera indonesia 6 (2), 2021, 173-188 table 3. description of sampling point no point location soil type (usda) slope 1 8° 9'35.03"s and113°52'15.78"e entisols >15% 2 8°28'32.64"s and 113°44'11.57"e entisols >15% 3 8°25'33.69"s and 113°33'22.83"e entisols >15% 4 8°12'36.80"s and 113°49'35.96"e entisols >15% 5 8° 4'5.05"s and 113°41'34.13"e inceptisols >15% 6 8° 3'32.04"s and 113°41'14.87"e andisols >15% 7 8°15'46.99"s and 113°26'39.22"e entisols >15% 8 8° 5'7.33"s and 113°55'41.86"e entisols >15% 9 8° 7'24.08"s and 113°32'10.28"e inceptisols >15% 10 8°22'33.31"s and 113°29'9.56"e entisols >15% 11 8° 3'47.32"s and 113°54'46.28"e entisols 0-15% 12 8° 9'52.26"s and 113°49'8.08"e entisols 0-15% 13 8°25'20.38"s and 113°38'26.77"e alfisols 0-15% 14 8°21'8.97"s and 113°43'32.91"e entisols 0-15% 15 8°23'18.30"s and 113°29'55.03"e alfisols 0-15% 16 8°22'29.71"s and 113°27'25.17"e entisols 0-15% 17 8°11'42.78"s and 113°48'39.85"e entisols 0-15% 18 8° 8'8.48"s and 113°43'37.86"e inceptisols 0-15% 19 8°19'13.73"s and 113°39'55.27"e alfisols 0-15% 20 8°13'53.39"s and 113°36'39.03"e entisols 0-15% 21 8°24'10.97"s and 113°35'25.46"e entisols 0-15% 22 8° 5'51.76"s and 113°55'0.90"e entisols 0-15% 23 8°10'43.78"s and 113°34'45.28"e inceptisols 0-15% 24 8°17'0.95"s and 113°21'10.73"e entisols 0-15% interpreted from: (usda soil survey staff, 2014). figure 3. soil sampling location 179 putri tunjung sari et al. / geosfera indonesia 6 (2), 2021, 173-188 2.2.2 laboratory analysis laboratory analysis was used to measure the physical, chemical, and biological properties of the soil samples. the soil samples were initially dried and sieved. the physical properties were analyzed using a 2 mm sieve, while the chemical analysis used a 0.5 mm sieve. table 4 shows the physical, chemical, and biological properties of soil samples used in this study. table 4. physical, chemical, and biological properties variable sample type method chemical properties ph disturbed soil the soil-water suspension (1:25) total phosphorus disturbed soil percolation with hcl 25% available potassium (k) disturbed soil neutral n nh4oac physical properties % sand disturbed soil pippet % silt disturbed soil pippet % clay disturbed soil pippet effective soil depth disturbed soil measurement biological properties c-organic disturbed soil curmis sources: (japan international cooperation agency (jica), 2014; panday et al., 2019) 2.2.3 principal component analysis (pca) the soil properties determined via laboratory analysis were then used as input for correlation and principal component analysis (pca). the data processed by pca include ph, total phosphorus (p), available potassium (k), % sand, % silt, % clay, effective soil depth, and c-organic. meanwhile, the procedure for this method includes (1) analyzing the correlation between factors, (2) conducting principal component analysis (pca), and (3) determining the minimum data set. 2.2.4 assessment of soil quality index (sqi) sqi was calculated and performed using gis software. first, the mds variable component was added to the sampling points,then, the indicator was interpolated using inverse distance weighted (idw). the results were then used to calculate sqi, using the formula in equation 1 (eq.1): sqi = (1) where, wi = weighting factor; and si = the indicator score for variable i. then, table 5 shows the score and class used to determine the sqi. 180 putri tunjung sari et al. / geosfera indonesia 6 (2), 2021, 173-188 table 5. class of soil quality index score class of soil quality index 0.80 – 1.00 very good 0.60 – 0.79 good 0.40 – 0.59 medium 0.20 – 0.39 low 0.00 – 0.19 very low sources: (nusantara et al., 2018) 3. results and discussion 3.1 land unit map the number of land units were determined by overlaying and intersecting three input maps, i.e., land cover, soil type, and slope maps. the land cover map was interpreted from the sentinel-2 image of the area of interest (aoi) downloaded from the usgs website, which was then processed, and classified. after the pre-treatment task i.e., atmospheric correction, a mosaic of 4 scenes, composite, and image enhancement, the sentinel images were then classified using the supervised method and maximum likelihood algorithm following the standard image processing procedure of multispec tm. furthermore, the land cover classification accuracy reached 99%, while the thematic land cover obtained from the classification processes showed 5 primary classes, namely (1) annual vegetation which includes forested area and plantation, (2) settlement representing urban and pavement area, as well as other public facilities, (3) dryland or shrubland, (4) marginal land representing area occupied by heterogeneous agricultural land, cropland, and rural areas, (5) water body, and (6) paddy field, as shown in figure 1. soil type map was extracted from layer database and obtained from the soil research institute ( sri, 1966). the soil type map scale was 1:250.000, and the layer was then clipped with a regency boundary. furthermore, the slope map was derived from demnas (digital elevation model at the national level) downloaded from the official website of the national geospatial agency (big). the demnas had spatial pixel resolution relatively similar to sentinel image (± 10m). therefore, jember regency has six (6) land unit classes, representing paddy fields as shown in figure 4. 181 putri tunjung sari et al. / geosfera indonesia 6 (2), 2021, 173-188 1 (inceptisols soil type and slope > 15%) 2 (entisols soil type and slope > 15%) 3 (andisols soil type and slope > 15%) 4 (entisols soil type and slope 0-15%) 5 (inceptisols soil type and slope 0-15%) 6 (alfisols soil type and slope 0-15%) figure 4. land unit map 3.2 soil properties of paddy fields table 6 contains the soil properties measured using laboratory analysis. soil properties were collect at 24 sampling points, meanwhile, the laboratory analysis results of the chemical, physical and biological properties varied. each parameter affects the availability of plant nutrients. table 6. soil properties variables mean se min max ph 7.01 0.45 6.04 7.8 total p (mg/100 g) 12.29 4.81 4.86 29.83 available k (me/100 g) 1.25 0.52 0.47 1.25 sand (%) 48.10 23.22 4.97 88.99 silt (%) 24.39 22.76 1.85 89.08 clay (%) 27.50 16.16 5.22 65.26 soil depth (cm) 36.36 10.25 25 70 c-organic (%) 2.42 0.44 1.28 3.27 note : se= standart error 182 putri tunjung sari et al. / geosfera indonesia 6 (2), 2021, 173-188 the results show the variability in chemical, physical, and biological characteristics of soil samples with ph values ranging from 6.04 7.8, and an average of 7.01. this value is classified as slightly acidic to slightly alkaline (li et al., 2018).when the soil ph is too alkaline, nutrients become unavailable for plants, meanwhile, the optimal soil ph for plants is 6.5-7 (hanafiah, 2018). the total p-value between 4.86 29.83 mg /100g was categorized as the very low to intermediate class (eviati & sulaeman, 2009). p nutrients are essentially needed by plants, especially in the generative phase (yao et al., 2020). furthermore, plants absorb p elements in the form of primary and secondary orthophosphates ions (h2po4 and hpo4 2-). plants absorb p in the form of h2po4 when the ph is low and hpo42under high ph (hanafiah, 2018). table 6 shows a relatively neutral ph value, hence, plants absorb p in the form of hpo4 2-. the potassium (k) value ranged between 0.47 1.25 me / 100 g and is classed as the medium to high category. this nutrient is essentially needed by plants to fill rice grains (banerjee et al., 2018). potassium is a mobile element, hence leaching easily occurs. furthermore, the high amount of potassium needs to be balanced with high organic c which reduces the rate of erosion hence, the amount of leaching is reduced. table 6 shows that the c-organic value ranged between 1.28 3.27% ( from low to high). this content serves as an energy source for soil microorganisms, reduces erosion, improves soil texture and structure (arunrat et al., 2020). soil texture is the ratio between the fraction of sand, silt, and clay. meanwhile, clay fraction is very critical in providing soil nutrients. clay is a is negatively charged soil fraction that binds to cations needed by plants (arunrat et al., 2020). the texture analysis results of the 3 fractions (sand, silt, clay) also vary (table 6). soil dominated by clay fraction has more nutrients compared to sand fraction. sandy soils loss water rapidly and are unable to hold nutrients. the rice fields in jember regency also have varying soil depths. table 6 shows that the effective soil depth values ranged from 25 70 cm. it is defined as the depth of the soil that plant roots are able to penetrate. rice fields are managed intensively through a process of plowing, this condition causes silting of the soil adequate depth. 3.3 principal component analysis (pca) the principal component analysis consists of correlation analysis and determination of the minimum data set (mds). mds is a variable used in determining the soil quality index 183 putri tunjung sari et al. / geosfera indonesia 6 (2), 2021, 173-188 (sqi), while correlation analysis is used to determine the relationship between the observed variables. table 7 shows the correlation analysis results. table 7. correlation analysis total p available k c-organic soil depth ph sand silt clay total p 1.000 available k 0.206 1.000 c-organic 0.222 0.262 1.000 soil depth -0.328 -0.243 -0.389 1.000 ph -0.062 0.036 0.018 0.113 1.000 sand 0.096 -0.138 -0.543* 0.264 -0.155 1.000 silt 0.118 0.048 0.125 -0.073 0.312 -0.213 1.000 clay -0.157 -0.017 0.443 -0.100 0.374 -0.836* 0.245 1.000 note: * significant table 7 shows the correlation analysis results for each soil variable. sand and clay fractions have the highest correlation compared to other variables, with a value of -0.836. a negative value indicates that the relationship between the two is reversing. when the sand fraction value is high, the clay fraction value tends to be low and vice versa. furthermore, the lowest correlation result was found between c-organic and ph variables with a value of 0.018, which is in the shallow category. fetene & amera (2018) stated that c-organic has more effect on soil porosity and volume weight. the next procedure was extraction via principal component analysis (pca). the extraction results were in the form of minimum data sets used in scoring and determining the soil quality index (sqi). table 8 shows the principal component extraction results. the p-total as well as silt,and clay fraction variables were used in the sqi assessment. the significance level of the three variables was determined by the eigen value (mukherjee & lal, 2014). to be used as an mds indicator, this value needs to be > 1 (romadhona & arifandi, 2020). the eigen values for the principal components (pc) 1, 2, and 3 were all greater than one, hence, the three are applicable as mds indicators. the eigenvectors > 90% of the maximum value in each pc were used as an mds indicator (supriyadi et al., 2018). table 8 shows the three indicators of mds, i.e., clay and silt fraction, as well as total p. the mds factor weight was obtained by dividing the variance (%) by the cumulative (%) on pc3 with values of 0.477, 0.309, and 0.214 respectively. this weight value was used in the calculation of the soil quality index (sqi). 184 putri tunjung sari et al. / geosfera indonesia 6 (2), 2021, 173-188 table 8. pca results pcs pc1 pc2 pc3 eigenvalue 2.58 1.68 1.16 % of variance 32.28 20.96 14.45 cumulative % 32.28 53.24 67.68 eigenvectors p_total 0.117 0.696* 0.406 k_available 0.294 0.493 0.178 c_organic 0.743 0.312 -0.200 soil depth -0.445 -0.623 0.080 ph 0.341 -0.478 0.585 sand -0.874 0.184 0.295 silt 0.410 -0.150 0.677* clay 0.827* -0.423 -0.163 note: * mds variable 3.4 assessment of soil quality index (sqi) soil quality index assessment only used the pca result variable. three main factors were used to determine the soil quality index, i.e., the clay and silt fraction, as well as p-total. the results were categorized into three classes, i.e., very low, low, and medium (figure 5). furthermore, the map analysis results showed that 41.14% was in the very low category, 52.23% was in a low class, and 6.63% was in the medium category. figure 5. soil quality index (sqi) paddy fields in jember regency 185 putri tunjung sari et al. / geosfera indonesia 6 (2), 2021, 173-188 the low quality of paddy fields is due to intensive soil management and chemical inputs. in addition, majority of farmers use only chemical fertilizers without any organic supplement. meanwhile, organic fertilizers are released slowly, and the results are not visible (maas et al., 2017). the application of chemical fertilizers has a direct effect on plants (asvini & jithesh, 2018), therefore, most farmers do not use organic fertilizers. this condition shows that there is a need to improve the quality of the paddy soil to support sustainability. soil quality improvement needs to focus on improving soil fertility without damaging the environment. meanwhile, soil fertility is a determining factor in plant growth and development (karamanoli et al., 2017). organic fertilizers are applied to increase nutrient availability and soil physical properties (kidinda et al., 2015). 4. conclusion based on the results, three variables were found to strongly influence soil quality assessment namely total p, as well as clay and silt fraction. approximately 93.37% of the paddy field area was classed as very low-low quality due to the intensive use of chemical fertilizers without organic supplements. the addition of ameliorants such as organic fertilizer is needed to improve the soil's physical, chemical, and biological properties. this application is to be focused on areas with very low – low soil quality to increase the quality to medium. conflict of interest the authors declare no conflict of interest. references abdel rahman, m. a. e., zakarya, y. m., metwaly, m. m., & koubouris, g. (2021). decisphering soil spatial variability through geostatistics and interpolation techniques. sustainability (switzerland), 13(1), 1–13. https://doi.org/10.3390/su13010194. arunrat, n., kongsurakan, p., sereenonchai, s., & hatano, r. (2020). soil organic carbon in sandy paddy fields of northeast thailand: a review. agronomy, 10(8), 1–25. https://doi.org/10.3390/agronomy10081061. asvini, b., & jithesh. (2018). impact of using artificial fertilizer in soil. international journal of pure and applied mathematics, 119(17), 47–55. bahnemiri, a. k., abkenar, k. t., kooch, y., & salehi, a. (2019). valuation of soil and litter quality indices using analysis hierarchical process (ahp) in hyrcanian beech forest stands, northern iran (case study: korkoroud forests in noshahr). journal of forest science, 65(10), 397–407. https://doi.org/10.17221/54/2019-jfs. https://www.acadpubl.eu/hub/2018-119-17/1/5.pdf 186 putri tunjung sari et al. / geosfera indonesia 6 (2), 2021, 173-188 balai penelitian tanah (2015). soil type map. retrieved from https://balittanah.litbang.pertanian.go.id/ind/. banerjee, h., ray, k., dutta, s. k., majumdar, k., satyanarayana, t., & timsina, j. (2018). optimizing potassium application for hybrid rice (oryza sativa l.) in coastal saline soils of west bengal, india. agronomy, 8(12), 1–14. https://doi.org/10.3390/agronomy8120292. big (1999). seamless digital elevation model (dem) dan batimetri nasional. retrieved from h http://tides.big.go.id/demnas/. bofana, j. do r., & costa, a. c. c. (2017). comparison of spatial interpolators for variability analysis of soil chemical properties in cuamba (mozambique). african journal of agricultural research, 12(25), 2153–2162. https://doi.org/10.5897/ajar2016.12415. eviati & sulaeman. (2009). petunjuk teknis analisis kimia tanah, tanaman , air dan pupuk. jakarta : balai penelitian tanah. fetene, e. m., & amera, m. y. (2018). the effects of land-use types and soil depth on soil properties of agedit watershed, northwest ethiopia. ethiopian journal of science and technology, 11(1), 39. https://doi.org/10.4314/ejst.v11i1.4. hanafiah, k. . (2018). basic of soil science. depok : raja grafindo persada. hore, r., chakraborty, s., bari, m. f., shuvon, a. m., & ansary, m. a. (2020). soil zonation and the shaking table test of the embankment on clayey soil. geosfera indonesia, 5(2), 196–209. https://doi.org/10.19184/geosi.v5i2.17873. hung, d. t., hughes, h. j., keck, m., & sauer, d. (2019). rice-residue management practices of smallholder farms in vietnam and their effects on nutrient fluxes in the soilplant system. sustainability (switzerland), 11(1641), 1–15. https://doi.org/10.3390/su11061641. japan international cooperation agency (jica) (2014). soil analysis manual. bandung : ntc international co., ltd. johannes, h. p., priadi, c. r., & herdiansyah, h. (2019). organic rice farming: an alternative to sustainable agriculture. iop conference series: materials science and engineering, 546(2). https://doi.org/10.1088/1757-899x/546/2/022008. karamanoli, k., papaioannou, a., & sofogianni, s. (2017). soil fertility and productivity estimation of pinus pinaster aiton reforestations in central and northeast chalcidice in northern greece. journal of forest science, 63(10), 470–475. https://doi.org/10.17221/68/2017-jfs. kidinda, l. k., bandi, b. t. k.-, mukalay, j. b., kabemba, m. k., ntata, c. n., ntale, t. m., tamina, d. t., & kimuni, l. n. (2015). impact of chicken manure integration with mineral fertilizer on soil nutriments balance and maize (zea mays) yield: a case study on degraded soil of lubumbashi (dr congo). american journal of plant nutrition and fertilization technology, 5(3), 71–78. https://doi.org/10.3923/ajpnft.2015.71.78. 187 putri tunjung sari et al. / geosfera indonesia 6 (2), 2021, 173-188 li, d., nanseki, t., chomei, y., & fukuhara, y. (2018). impact of soil chemical properties on rice yield in 116 paddy fields sampled from a large-scale farm in kinki region, japan. iop conference series: earth and environmental science, 185(1). https://doi.org/10.1088/1755-1315/185/1/012026. lin, h. c., & fukushima, y. (2016). rice cultivation methods and their sustainability aspects: organic and conventional rice production in industrialized tropical monsoon asia with a dual cropping system. sustainability (switzerland), 8(529), 1–23. https://doi.org/10.3390/su8060529. maas, e. d. v. l., lal, r., coleman, k., montenegro, a., & dick, w. a. (2017). modeling soil organic carbon in corn (zea mays l.)-based systems in ohio under climate change. journal of soil and water conservation, 72(3), 191–204. https://doi.org/10.2489/jswc.72.3.191. mohawesh, y., taimeh, a., & ziadat, f. (2015). effects of land-use changes and soil conservation intervention on soil properties as indicators for land degradation under a mediterranean climate. solid earth, 6(3), 857–868. https://doi.org/10.5194/se-6-8572015. mukherjee, a., & lal, r. (2014). comparison of soil quality index using three methods. plos one, 9(8), 1–16. https://doi.org/10.1371/journal.pone.0105981. nusantara, r. w., aspan, a., alhaddad, a. m., suryadi, u. e., makhrawie, fitria, i., fakhrudin, j., & rezekikasari. (2018). peat soil quality index and its determinants as influenced by land use changes in kubu raya district, west kalimantan, indonesia. biodiversitas, 19(2), 540–545. https://doi.org/10.13057/biodiv/d190229. panday, d., ojha, r. b., chalise, d., das, s., twanabasu, b., & tejada moral, m. (2019). spatial variability of soil properties under different land use in the dang district of nepal. cogent food & agriculture, 5(1), 1–19. https://doi.org/10.1080/23311932.2019.1600460. pierzynski, g. m., sims, j. t., & vance, g. f. (2005). soil and environmental quality. florida : crc press taylor and francis group. reddy, r. s., babu, g. a., & reddy, a. r. m. (2020). geospatial approach for the analysis of forest cover change detection using machine learning. geosfera indonesia, 5(3), 335–351. https://doi.org/10.19184/geosi.v5i3.20157. ren, x., chen, f., ma, t., & hu, y. (2020). soil quality characteristics as affected by continuous rice cultivation and changes in cropping systems in south china. agriculture (switzerland), 10(10), 1–11. https://doi.org/10.3390/agriculture10100443. romadhona, s., & arifandi, j. a. (2020). indeks kualitas tanah dan pemanfaatan lahan sub daerah aliran sungai suco kabupaten jember. geography: jurnal kajian, penelitian dan pengembangan pendidikan, 8(1), 37–45. roy, r., chan, n. w., & xenarios, s. (2015). sustainability of rice production systems: an empirical evaluation to improve policy. environment, development, and sustainability, 18(1), 257–278. https://doi.org/10.1007/s10668-015-9638-x. 188 putri tunjung sari et al. / geosfera indonesia 6 (2), 2021, 173-188 seifu, w., & elias, e. (2018). soil quality attributes and their role in sustainable agriculture: a review. international journal of plant & soil science, 26(3), 1–26. https://doi.org/10.9734/ijpss/2018/41589. supriyadi, mustikaningrum, i. a., herawati, a., purwanto, p., & sumani, s. (2018). soil quality assessment in organic and non-organic paddy fields in susukan, indonesia. bulgarian journal of agricultural science, 24(5), 777–784. supriyadi, s., sih dewi, w., nugrahani, d., rahmah, a. a., haryuni, h., & sumani, s. (2019). the assessment of soil quality index for paddy fields with indicator biology in jatipurno districts, wonogiri. modern applied science, 14(1), 20–33. https://doi.org/10.5539/mas.v14n1p20. terano, r., mohamed, z., shamsudin, m. n., & latif, i. a. (2015). farmers sustainability index: the case of paddy farmers in state of kelantan, malaysia. journal of the international society for southeast asian agricultural sciences, 21(1), 55–67. usda soil survey staff. (2014). keys to soil taxonomy. washington dc : usda. usgs (2019). sentinel-2 imagery. retrived from https://www.usgs.gov/centers/eros/science/usgs-eros-archive-sentinel-2. van grinsven, h. j. m., erisman, j. w., de vries, w., & westhoek, h. (2015). potential of extensification of european agriculture for a more sustainable food system, focusing on nitrogen. environmental research letters, 10(2). https://doi.org/10.1088/17489326/10/2/025002. xie, h., huang, y., chen, q., zhang, y., & wu, q. (2019). prospects for agricultural sustainable intensification: a review of research. land, 8(11), 1–27. https://doi.org/10.3390/land8110157. yao, h., chen, x., yang, j., li, j., hong, j., hu, y., & mao, x. (2020). effects and mechanisms of phosphate activation in paddy soil by phosphorus activators. sustainability (switzerland), 12(9), 1–15. https://doi.org/10.3390/su12093917. http://agrojournal.org/24/05-07.html https://www.researchgate.net/profile/rika-terano-3/publication/282985792_farmers_sustainability_index_the_case_of_paddy_farmers_in_state_of_kelantan_malaysia/links/56751a7408aebcdda0e10f61/farmers-sustainability-index-the-case-of-paddy-farmers-in-state-ofhttps://www.researchgate.net/profile/rika-terano-3/publication/282985792_farmers_sustainability_index_the_case_of_paddy_farmers_in_state_of_kelantan_malaysia/links/56751a7408aebcdda0e10f61/farmers-sustainability-index-the-case-of-paddy-farmers-in-state-ofacknowledgement the editorial board would like to thank and express appreciation to all peer reviewers who have reviewed the manuscripts for publication of geosfera indonesia. marinela istrate (scopus id : 56672996500) department of geography, universitatea alexandru ioan cuza, iasi, romania lucian rosu (scopus id : 56958158800) department of geography, universitatea alexandru ioan cuza, iasi, romania mihai niculita (scopus id : 55022909500) department of geography, alexandru ioan cuza university of iasi, romania tin lukic (scopus id : 54795557700) department of geography, university of novi sad, serbia fatih adiguzel (scopus id : 57204062132) , department of geography, nevşehir haci bektaş veli üniversitesi, nevsehir, turkey elan artono nurdin (scopus id : 57192649049) department of geography education, university of jember, indonesia bejo apriyanto (scopus id : 57208468203) department of geography education, university of jember, indonesia prima widayani (scopus id : 57188879871) faculty of geography, gadjah mada university, indonesia ivan taslim (scopus id : 57203022349) department of geography, universitas muhammadiyah gorontalo, indonesia efdal kaya (scopus id : 57202135756) department of architecture and urban planning, iskenderun technical university, iskenderun, turkey batuhan kilic (scopus id : 57204675825) geomatic engineering department, yildiz technical university, istanbul, turkey rendra zainal maliki department of geography education, universitas tadulako, indonesia faisal arif setiawan department of geography education, universitas lambung mangkurat, indonesia aulia ulfa farahdiba (scopus id : 57208130620) , department of environmental engineering, universitas pembangunan nasional "veteran" jawa timur, indonesia guruh samodra (scopus id : 55053491600) faculty of geography, universitas gadjah mada, yogyakarta, indonesia wahid akhsin budi nur sidiq (scopus id : 57201676728), department of geography, universitas negeri semarang, semarang indonesia pertiwi andarani (scopus id : 55959123900), department of environmental engineering, universitas diponegoro, semarang, indonesia https://www.scopus.com/authid/detail.uri?authorid=56672996500 https://www.scopus.com/authid/detail.uri?authorid=56958158800 https://www.scopus.com/authid/detail.uri?authorid=55022909500 https://www.scopus.com/authid/detail.uri?authorid=54795557700 https://www.scopus.com/authid/detail.uri?authorid=57204062132 https://www.scopus.com/authid/detail.uri?authorid=57192649049 https://www.scopus.com/authid/detail.uri?authorid=57208468203 https://www.scopus.com/authid/detail.uri?authorid=57188879871 https://www.scopus.com/authid/detail.uri?authorid=57203022349 https://www.scopus.com/authid/detail.uri?authorid=57202135756 https://www.scopus.com/authid/detail.uri?authorid=57204675825 https://scholar.google.co.id/citations?user=qivrcmkaaaaj&hl=id prama ardha aryaguna (scopus id : 56236908900), department of survey and mapping, faculty of engineering, universitas esa unggul, jakarta, indonesia ionuț minea (scopus id : 56951000900), faculty of geography and geology, department of geography, alexandru ioan cuza university, 20 a, carol i bd., 700505 iasi, romania rosmadi fauzi (scopus id : 6508044388), department of geography, university of malaya, kuala lumpur, malaysia mahendra andiek maulana (scopus id : 57189494749), faculty of civil engineering planning and earth science, institut teknologi sepuluh nopember, surabaya, indonesia very dermawan (scopus id : 57190389285), water resources engineering department, universitas brawijaya, malang, indonesia geos geosfera indonesia geosfera indonesia is a journal publishes original research, review, and short communication (written by researchers, academicians, professional, and practitioners from all over the world) which utilizes geographic and environment approaches (human, physical landscape, nature-society and gis) to resolve humanenvironment interaction problems that have a spatial dimension. moreover, geosfera indonesia also committed to enhance and share original research, review, and short communication (written by researchers, academicians, professional, and practitioners from all over the world) on geography education and environmental education. our journal's scope includes : 1. geography education 2. physical geography 3. human geography 4. geographic information system (gis) 5. remote sensing 6. environmental science 7. environmental education 8. disaster risk reduction indexed by : m. musnajam et al / geosi vol 5 no 2 (2020) 250-267 the facies and metamorphism types determination of metamorphic rock in the part of mekongga complex m. musnajam1*, ahmad tarmizi abd karim2,n. nurfadillah3, fahrudi ahwan ikhsan4, andri estining sejati5 1mining engineering study program, universitas sembilanbelas november kolaka, jl. pemuda 339, kolaka, 93561, indonesia 2faculty of civil and environmental engineering, universiti tun hussein onn malaysia, parit raja, batu pahat johor, 86400, malaysia 3department of geology engineering, universitas halu oleo, kampus hijau bumi tridharma anduonou, kendari, 93132, indonesia 4department of geography education, universitas jember, jl. kalimantan 37, jember, 68121, indonesia 5geography education study program, universitas sembilanbelas november kolaka, jl. pemuda 339, kolaka, 93561, indonesia *corresponding author : musnajam3@gmail.com received 5 april 2020/ revised 15 july 2020 / accepted 21 july 2020/ available online 28 july 2020 abstract lambolemo village is geomorphologically dominated by hilly slopes morphology. lithology in the form of metamorphic rocks are mica schists and chlorite schists. the present research aimed to determine the facies and metamorphism types of metamorphic rocks in lambolemo village. the research methods engaged were field observation and laboratory observation utilizing petrographic analysis. observations stage generated texture data and set of mineral both macroscopically and microscopically. the minerals were discovered within metamorphic rock of the research area, namely: muscovite, quartz, biotite, and chlorite. these findings then classified into two zones, there were chlorite zone and biotite zone. these zones were embodied into greenschist facies with chlorite mineral index. the greenschist facies was characterized with chlorite, albit, epidote, and actinolite minerals appearance. the metamorphic rock had a foliation structure. the structure was commonly generated by a regional metamorphic process, which was particularly a feature of the clear alignment, translucent minerals from flat minerals, such as : mica, chlorite and minerals that obtained fibers or scents. keywords: determination; facies; metamorfism type 1. introduction the rock cycle illustrates the process of rock formation, started from magma to magma. rock that located in extreme deep point experiences changes from pressure and temperature. according to ahmed et al. (2017) the process of rock forming until turns to geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.5 no. 2 (2020), 250-267, august, 2020 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v5i2.17340 accredited by the ministry of research , technology , and higher education of the republic of indonesia, no. 30/e/kpt/2019. 250 mailto:musnajam3@gmail.com https://jurnal.unej.ac.id/index.php/geosi https://drive.google.com/file/d/1rsnvas6cuhowhl5bj87cl2l6k5dqz7s6/view 251 m. musnajam et al / geosi vol 5 no 2 (2020) 250-267 magma is known as the rock cycle. according to (kurnianto et al., 2018) ijen volcano existence is the example of volcanic rock deposits producing, which means rock is derived from magma. the deep zone rock, once reaches a certain temperature, would melt into magma. rock that have not reached the melting zone then changes into metamorphic rock. the process is known as the metamorphism process. according to hasria et al. (2017) metamorphic rock development is a result of magma and pressure. according to (ca et al., 2019) one of the basement rocks envolved is metamorphism. the metamorphism process leads texture and mineral composition from previous rock changed. both of these components could determine facies metamorphism that formed in a region zone. metamorphic facies is metamorphic rock group with similar condition which is characterized by a group of permanent mineral. according to geng et al. (2018) facies metamorphism in china is the outlined of the metamorphic rock map zone. lambolemo village is an area located in samaturu district, kolaka regency. this area is geomorphologically dominated with the sloping hills. based on the pre-research stage, the lithology of this area was composed of metamorphic mica schist and chlorite schist. then, the findings of mineral rock composition were optic mineral, facies, and metamorphism types. referring to the geological map of the lasusua-kendari sheet, this area is dominated by metamorphic rocks. the region is attached to the mekongga complex which is the oldest rock constituent formation in the southeast arm of sulawesi. according to hamimu et al. (2019) there are two metamorphic rock complexes in southeast sulawesi, namely pompangeo complex and mekongga complex. considering the results of early measurements of foliation upon research location, metamorphic rocks were generally dominated by the southeast-northwest direction. the southeast-northwest direction was the general direction of the strike slip fault on the southeastern arm of sulawesi. referring to surono (2013) both kolaka fault and the konaweha fault are active and affecting the surrounding rock. furthermore, according to (maulana et al., 2018) the fault direction likely affect the development of metamorphic rock zone. the research object was simulating, since it recorded complex geological information. research regarding rock determinism which concerned facies and metamorphism types in the mekongga complex has not been conducted. geological maps were slightly limited to the general type of rocks. according to tóth & schubert (2018) the formation of complex metamorphic rocks has become a distinctive study as in the körös complex in hungary. 252 m. musnajam et al / geosi vol 5 no 2 (2020) 250-267 the relevant research (soesilo et al., 2015) identified the metamorphism type of metamorphic belt in the area between java sea and mangkalihat peninsula and also western part of central sulawesi. the research (setiawan et al., 2015) revealed the metamorphic evolution through determining the facies and metamorphism type of meratus complex in south kalimantan. the research (chen et al., 2018) investigated the metamorphic rocks in wuliangshan mountains with the facies and metamorphism types. nugraha & hall (2018) focused in wallace biodiversity area that determined the petrology and heavy mineral with depositional environments. the research (moniruzzaman et al., 2014) concerned in determining the mineral elements for human nutritions. the research (kurnianto & nurdin, 2020) conducted observation of rock stratigraphy by investigating the patterns and types of rocks and also engaging digital elevation model (dem) and medium format photo. there have been limited studies concerned on how to determine the other minerals (facies and metamorphism type such as depositional, nutrients, and dem). therefore, this research intended to collect detail findings relating metamorphic rocks that were not tagged neither in the geological map nor in other rock research within mekongga complex section. the objective of this research was to determine the facies and metamorphism types of metamorphic rock in part of mekongga complex in lambolemo village, samaturu district, kolaka regency, southeast sulawesi, indonesia. 2. methods the research types of this study were field research and laboratory research. field research in the sense of lithological observation and measurement of foliation. while, laboratory research in the form of rock slice obsevaration sample used petrographic methods. this research was conducted in may, 2017 in lambolemo village, samaturu district, kolaka regency, southeast sulawesi. according to (anggara et al., 2018) the petrographic method is engaged in obtaining the microscopic data. the research data consisted of primary and secondary data. primary data was attained from direct observations in the field and laboratory analysis results of the texture and mineral type of metamorphic rocks. field data in the form of lithology and foliation data, while the results of laboratory analysis in the form of texture and mineral type of metamorphic rocks. secondary data was obtained from regional geological maps within research area. according to (idrus et al., 2014) regional geological map performs as a complement in analyzing the metamorphic rock complex. according to (amaluddin et al., 2019; nursalam et al., 2019) 253 m. musnajam et al / geosi vol 5 no 2 (2020) 250-267 geological and geography maps are functioning as additional and instant information for research. the research instruments is described in the table 1 below. table 1. the research instruments no. instrument functions 1. topography map on scale 1:25.000 based map for field orientation, plotingfield point observation, and identified topography condition. 2. gps (global positioning sistem) recorded the coordinate point 3. geology compass determined the picture and drawing direction 4. geology hammer collected sampling 5. loupe observed the rock constituent minerals in the field 6. field note media to record data observation 7. stationery recorded the results of field observations 8. meterrol measured outcrop dimensions 9. sample bag a safety to put rock samples 10. camera captured images 11. microscope investigated rock samples microscopically research procedures followed 4 steps. first step was preparation. preparation is all kinds of preparation activities regarding field equipment and literature study. field equipment has been described in table 1 above. literature study was objected to determine regional geological conditions, research methods and literature of metamorphic rocks. second step was collecting both primary and secondary data. third step was data analysis. during this step, rock samples were selected for petrographic analysis. the rock samples being analyzed were sliced with a thickness of 0.03 mm and 0.05 mm to be observed under a polarization microscope. the tool used in analyzing metamorphic rocks was a nikon ufx-dx series magnification of the 10x ocular lens and 10x, 20x and 40x magnification objective lenses. the meaning of microscopic,since it used the polarization microscope to determine the slice of minerals. the macroscopic means to analyze the mineral not guiding by microscope or determination by direct observation. fourth was formulating conclusion based on rock samples observation using petrographic method as the results of texture and metamorphic rock minerals similarities within the reseach area. according to this data, it could be used to determine the metamorphism facies formed in the reseach area and the metamorphism type of the research 254 m. musnajam et al / geosi vol 5 no 2 (2020) 250-267 area by investigating the classification of metamorphism facies and the metamorphism type determination. the figure 1 shows the research flow diagram. figure 1. research flow diagram 3. results and discussion the research area covered two types of rocks namely mica schist and chlorite schist. macroscopic and microscopic description of mica schist macroscopically had a gray appearance in fresh condition and brown-colored in weathered condition. rock texture was lepidoblastic, with foliation rock structure. the mineral composition were muscovite, quartz, and biotite. figure 2 shows the rock figure of mica schist location. figure 2. mica schist rocks with photo direction n 2500 e preparation steps literature study data collection steps primary data: lithology& foliation secondary data: regional geology map macroscopic and microscopic data analysis field tools petrography metamorphic rock texture facies classification and metamorphic type determination facies and metamorphic type biotite muscovite 255 m. musnajam et al / geosi vol 5 no 2 (2020) 250-267 each mineral description that formed rock could be seen in the table 2 below. table 2. the description of minerals of rock framer in mica schist no. mineral percentage mineral description 1. muscovite 70 gray, white spout, glass luster, perfect cleavage, concoidal fracture, 2.5 mohs hardness scale 2. quartz 15 white-colored, white spout, glass luster, no cleavage, concoidal fracture, 6.5-7 mohs hardness scale 3. biotite 15 black, black spout, glass luster, no cleavage, concoidal fracture, hardness 2.5 mohs hardness scale table 3 shows the result mica schist mineral sample. table 3. rock framer of mica schist identification sample number structure type microscopic 1 schistosic the slice was purplish blue-shaped, lepidoblastic in texture, mineral composition formed of muscovite, quartz, biotite and opaque minerals. 3 schistosic the slice was purplish blue-shaped, lepidoblastic in texture, mineral composition formed of muscovite, quartz and opaque minerals. 4 schistosic the slice was purplish blue-shaped, lepidoblastic in texture, mineral composition formed of muscovite, quartz and opaque minerals. 6 schistosic this stone slice was brown, lepidoblastic texture, mineral composition formed of muscovite, quartz, biotite and opaque minerals. 7 schistosic this slice was purplish blue-shaped, lepidoblastic in texture, mineral composition formed of muscovite, quartz, oxide minerals and opaque minerals. 8 schistosic the slice was purplish blue-shaped, lepidoblastic in texture, mineral composition formed of muscovite, quartz, biotite and opaque minerals. 9 schistosic the stone slice was purplish blue-shaped, lepidoblastic texture, mineral composition formed of muscovite, quartz and opaque minerals. 11 schistosic the stone slice was purplish blue-shaped,lepidoblastic texture, mineral composition formed of muscovite and quartz. 12 schistosic the slice was purplish blue-shaped, lepidoblastic in texture, mineral composition formed of muscovite, quartz, biotite and opaque minerals. figures 3 and 4 illustrate the result mica schist mineral sample 256 m. musnajam et al / geosi vol 5 no 2 (2020) 250-267 figure 3. mica schist sample number 1 figure 4. mica schist sample number 12 the description of macroscopic and microscopic of the chlorite schist. macroscopically, it had gray-colored appearance in fresh conditions and brown in weathered conditions. the rock texture was lepidoblastic with foliation rock structure. mineral composition were chlorite and muscovite. figure 5 shows the rock in the chlorite schist location. 257 m. musnajam et al / geosi vol 5 no 2 (2020) 250-267 figure 5. chlorite schist rocks with photo direction n 1620 e each mineral description that formed rock could be seen in the table 4 below. table 4. the description of rock framer minerals of chlorite schist no mineral percentage mineral description 1. chlorite 70 greenish, white spout, glass luster, no cleavage, concoidal fracture, 2.5 mohs hardness scale 2. muscovite 15 gray, white spout, glass luster, perfect cleavage, concoidal fracture, 2.5 mohs hardness scale table 5 shows the result chlorite schist mineral sample. table 5. rock framer of chlorite schist identification sample number structure type microscopic 2 schistosic these rock slices were green, lepidoblastic texture, mineral formed of chlorite and muscovite. 5 schistosic these rock slices were green, lepidoblastic in texture, mineral composition formed of chlorite and muscovite. 10 schistosic this slice of rock was grayish green, lepidoblastic in texture, mineral formed of chlorite, quartz and opaque minerals. chlorite muscovite 258 m. musnajam et al / geosi vol 5 no 2 (2020) 250-267 figure 6 and 7 present the result of chlorite schist mineral sample. figure 6. chlorite schist sample number 2 figure 7. chlorite schist sample number 10 the metamorphic descriptions in megascopic are based on color appearance, texture, structure and mineral composition. color is a physical property of minerals that can be 259 m. musnajam et al / geosi vol 5 no 2 (2020) 250-267 directly observed. color does not entirely reflect the original color of the mineral, since the mineral color is not only derived from the mineral itself, but also occurs from other substances which pollute the mineral. according to (nelson eby et al., 2015) first identification and description relating to mineral is based on the color, for example the glass green in color. lepidoblastic texture is a metamorphic rock texture based on mineral form, this texture is dominated by the presence of flat rock-forming minerals. foliation structure is the presense of a planar structure in a rock mass. according to (bucher & rodney, 2011) the texture and structure of the rock characterize the identification of rock minerals, one of which is the foliation structure. according to (cárdenes et al., 2013) the mica matric of muscovite has typical lepidoblastic texture. this foliation could occur due to the juxtaposition of minerals into layers (gneissossity), grain orientation (schistossity), planar cleavage surface (cleavage). foliation is can combine of its. according to (usda, 2012) foliation shaped from gneissosity, schistosity, cleavage, and banned rock with code 7-10. according to (song & suh, 2014) across foliation could be found upon rock samples that were taken in the mid-west region of south korea. mica schist microscopically had purplish-blue, lepidoblastic texture, schistose structure. the mineral composition composed of muscovite, quartz, biotite, and opaque minerals. figure 8 shows the rock figure found in the mica schist of the small slice. figure 8. schist mica rock in the small slice (a) muscovite, (b) quarts, (c) biotite, (d) opaque mineral, (e) clay mass based d b c e a 260 m. musnajam et al / geosi vol 5 no 2 (2020) 250-267 each mineral description that formed rock could be seen in the table 6 below. table 6. optic description of mica schist mineral mineral composition percentage optic mineral information muscovite (a) 50 purplish blue-colored interference, dichroic pleochroism, subhedral shape, 1-way cleavage, no fracture, high relief, high intensity, mineral size 0.01-0.10 mm, darkenss angle 42°, oblique darkness type. quarts (b) 15 grayish white interference color, dichroic pleochroism, subhedral-anhedral shaped, no cleavage, no fracture, low relief, low intensity, mineral size 0.02-0.5 mm, darkness angle 47°, corrugated darkness type. biotite (c) 15 brown interference color, dichroic pleochroism, subhedralanhedral shaped, no cleavage, no fracture, moderate relief, moderate intensity, mineral size 0.02-0.5 mm, darkness angle 90 °, parallel darkness type. opaque mineral (d) 10 colorless, anhedral (glass) shaped, low intensity, low relief, size 0.1-0.10 mm. clay mass base (e) 10 black, translucent, subhedral-anhedral shaped, the high mineral intensity with high relief and mineral size 0.020.08 mm. chlorite schist microscopically was green-colored, lepidoblastic texture, schistocic structure. mineral composition composed of chlorite and muscovite. figure 9 shows the rock figure found in chlorite schist of the small slice. figure 9. schist chlorite rock in the small slice: (a) muscovite, (b) chlorite, (c) opaque mineral, (d) oxide mineral b c d a 261 m. musnajam et al / geosi vol 5 no 2 (2020) 250-267 each mineral description that formed rock could be seen in table 7. table 7. optic description of chlorite schist mineral mineral composition percentage optic mineral information muscovite (a) 20 purplish blue-colored interference, dichroic pleochroism, subhedral-shaped, 1-way cleavage, no fracture, high relief, high intensity, mineral size 0.010.8 mm, darkenss angle 38°, oblique darkness type. chlorite (b) 65 green interference-colored, dichroic pleochroism, anhedral-shaped, 1-way cleavage, no fracture, high relief, high intensity, mineral size 0.01-0.10 mm, darkness angle 27°, oblique darkness type. opaque mineral (d) 5 black, translucent, subhedral-anhedral shaped, the high mineral intensity with high relief and mineral size 0.01-0.2 mm. oxide mineral (e) 10 brown, anhedral-shaped, the moderate mineral intensity, moderate relief, and mineral size 0.01-0.8 mm. the microscopic description of metamorphic rocks is based on color appearance, texture, structure, and mineral composition. color is a representation of absorption appearance or wave length absorption upon light entering anisotropic minerals. lepidoblastic texture is a metamorphic rock texture composed of mineral form, this texture is dominated by the presence of flat rock-forming minerals. foliation structure is the appearance of a planar structure in a rock mass. foliation structures and concepts follow concepts (ahmed et al., 2017; bucher & rodney, 2011; usda, 2012). observation of mineral colors with megascopic handkerchief samples was significantly different compared to color observation microscopically. muscovite had dichroic pleochroism, since there were changes in two different colors, the shape of the mineral was observed by perceiving or observing the boundary areas as well as boundary lines of the mineral. muscovite had a sub hedral mineral form, in which the crystal was limited to only a part of the crystal itself. according to (singh et al., 2012) petrological samples have various type depending to the purpose, the megascopic or proximate analysis is thicker than microscopic or petgorraphic and chemical purpose. according to (xu et al., 2017) the minerals of oregon sunstones have dicroic, due to the color shifting from red to green. rocks found in the research area were mica schist and chlorite schist. mica schist was composed of muscovite, biotite, and quartz minerals. chlorite schist was composed of 262 m. musnajam et al / geosi vol 5 no 2 (2020) 250-267 chlorite, muscovite and quartz minerals. the four minerals were flat-shaped, each rock had a schistose structure and lepidoblastic in texture, naming the structure and texture referring to the structure and texture type division according to (usda, 2012). schistose is a foliation structure produced by the alignment of relatively large flat minerals such as mica and chlorite. lepidoblastic is a metamorphic rock texture that is dominated by flat minerals and shows a parallel orientation such as biotite and muscovite minerals. the determination of the type of protolith rock was based on the petrographic analysis. through thin slice petrography analysis, it was recognized that the metamorphic rock in the research area was dominated by quartz and muscovite minerals, a side from there was also a clay base mass, which indicated the protolith of the schist within research area was originated from sedimentary rock, namely claystone. according to (bucher & rodney, 2011; kohn, 2014; lanari et al., 2019) slicing is a technique to anaylize rocks and minerals. based on schist constituent mineral in the research area, it was divided into 6 mineral groups. the rock constituent minerals were chlorite and muscovite; chlorite and quartz; muscovite and quartz; muscovite, quartz, biotite, and chlorite; muscovite, quartz, and biotite; biotite and quartz. according to (lewerentz, 2017) the mineral assemblage of chlorite and muscovite, chlorite and quartz, as well as muscovite and quartz are embodied into chlorite zone which is characterized by the presence of quartz, chlorite, muscovite and albite minerals. furthermore (lewerentz, 2017) describes the set of mineral muscovite, quartz, biotite and chlorite; muscovite, quartz and biotite; and biotite and quartz are embodied into the biotite zone which is characterized by the presence of quartz, muscovite, biotite, chlorite, and albite minerals. other reinforcement concepts by (kohn, 2014) related to names given to various facies. the name is based on a set of mineral groups that will develop in mass mafic compositions under various pressure, temperature and mineral conditions that define each facies. especially related to temperature through temperature-time analysis. based on zoning by (lewerentz, 2017), schist of the study area was embodied into the chlorite zone and biotite zone, both zones were included in the greenschist facies with index minerals, namely chlorite. chlorite was located at the bottom of the schist, then with high temperature of the greenschist the low-schist green high was characterized by the presence of biotite with 4250-4500 c temperature, in line with the metamorphism facies chart by (kohn, 2014). according to (noor et al., 2016) the greenschist facies are characterized by chlorite, biotite, muscovite, clay, and codierite. 263 m. musnajam et al / geosi vol 5 no 2 (2020) 250-267 according to the metamorphic rocks observation of the research area, it had a foliation structure. foliation structure was marked through the alignment of metamorphic minerals and schistosic structures, a structure in which flat minerals (biotite, muscovite) were more dominant than granular minerals. this structure was primarily a result of a regional metamorphosis process, very typical were the clear pieces of flat minerals such as mica, chlorite and fibers mineral. according to (bucher & rodney, 2011) regional metamorphism occurs in a significant wide area while local metamorphism occurs in quite a narrow area ranging from a few meters to kilometers. according to (candan et al., 2016) the gabbroic dikes in tauride block, western turkey is one of several small locations samples that is wellpreserved as locally metamorphic rock converted into eclogitic metagabbros and amphibolites. there have been limited studies concerning on how to determine the mineral (facies and metamorphism type such depositional by (nugraha & hall, 2018), nutrients by (moniruzzaman et al., 2014), and digital elevation model (dem) by (kurnianto & nurdin, 2020). the research finding was related to the determination of facies and metamorphism types of metamorphic rock. according to (moniruzzaman et al., 2014) the determination of minerals occupies important information about mineral from various regions for human life benefits. the finding research indicated the minerals determination within mekongga complex section that mica schist and chlorite schist were included in the greenschist facies and regional metamorphis process. prior this, the mineral was described macroscophic and microscophic. this revealed the research novelty, that the facies and metamorphis type part of mekongga complex in lambolemo village displayed differences towards the findings of the metamorphic rocks that were not contained neither in the geological map nor the other rock research, specially in the mekongga complex section. 4. consclusion the metamorphic rocks in lambolemo village as part of mekongga complex reveals that mica schist and chlorite schist obtain lepidoblastic textures. the mica schist composed of muscovite, quartz, biotite, and opaque minerals. the chlorite schist composition formed of chlorite and muscovite. the schist mineral was embodied into the chlorite zone and biotite zone, both zones were embodied to wards the greenschist facies. both mica schist and chlorite schist metamorphism types were regional metamorphism. 264 m. musnajam et al / geosi vol 5 no 2 (2020) 250-267 conflict of interest the authors declare that there is no conflict of interest with any financial, personal, or other relationships with other people or organizations related to the material discussed in the article. acknowledgments thanks to universitas sembilanbelas november kolaka and the collaboration team in the universiti tun hussein onn malaysia, universitas jember, and universitas halu oleo that developed the engineering geography topic. references ahmed, k. j., zaki, m. m., rizvi, h. a., zoheb, m. m., & ansari, a. s. (2017). a review on rock cycle. international journal of emerging technologies and innovative research, 4(12), 100–102. http://www.jetir.org/papers/jetir1712021.pdf. amaluddin, l. o., rahmat, r., surdin, s., ramadhan, m. i., hidayat, d. n., sejati, a. e., purwana, i. g., & fayanto, s. (2019). the effectiveness of outdoor learning in improving spatial intelligence. journal for the education of gifted young scientists, 7(3), 667–680. https://doi.org/10.17478/jegys.613987. anggara, f., pamungkas, d., & prakoso, w. g. (2018). canwe identify macroscopic texture of coal under microscopic analysis using standard petrographic method?.journal of applied geology, 3(1), 32. https://doi.org/10.22146/jag.40005. bucher, k., & rodney, g. (2011). petrogenesis of metamorphic rocks. london: sparinger. https://doi.org/10.1007/978-3-540-74169-5. ca, a., oj, a., & lo, a. (2019). empirical relationship between gravimetric and mechanical properties of basement rocks in ado-ekiti, southwestern nigeria. j geol geophys, 9(1), 1–14. https://doi.org/10.35248/2381-8719.19.9.470. candan, o., koralay, o. e., topuz, g., oberhänsli, r., fritz, h., collins, a. s., & chen, f. (2016). late neoproterozoic gabbro emplacement followed by early cambrian eclogitefacies metamorphism in the menderes massif (w. turkey): implications on the final assembly of gondwana. gondwana research, 34(1), 158–173. https://doi.org/10.1016/j.gr.2015.02.015. cárdenes, v., rubio-ordoñez, a., monterroso, c., & calleja, l. (2013). geology and geochemistry of iberian roofing slates. chemie der erde, 73(3), 373–382. https://doi.org/10.1016/j.chemer.2012.11.004. chen, q., zhao, z., jiang, q., tan, s., & tian, y. (2018). identification of metamorphic rocks in wuliangshan mountains (southwest china) using aster data. arabian journal of geosciences, 11(12), 1–18. https://doi.org/10.1007/s12517-018-3635-y. 265 m. musnajam et al / geosi vol 5 no 2 (2020) 250-267 geng, y., shen, q., & song, h. (2018). metamorphic petrology and geology in china: a review. china geology, 1(1), 137–157. https://doi.org/10.31035/cg2018012. hamimu, l., ngkoimani, l. o., jahidin, j., asfar, s., & usmardin, u. (2019). analysis of the sub-surface distribution of graphite minerals using the geoelectrical resistivity method in the sabilambo village, kolaka regency,southeast sulawesi province. journal of geoscience, engineering, environment, and technology, 4(3), 149–157. https://doi.org/10.25299/jgeet.2019.4.3.2406. hasria, h., idrus, a., & warmada, i. w. (2017). the metamorphic rocks-hosted gold mineralization at rumbia mountains prospect area in the southeastern arm of sulawesi island, indonesia. journal of geoscience, engineering, environment, and technology, 2(3), 217–223. https://doi.org/10.24273/jgeet.2017.2.3.434. idrus, a., prihatmoko, s., gendoet hartono, h., idrus, f., & setiawan, i. (2014). some key features and possible origin of the metamorphic rock-hosted gold mineralization in buru island, indonesia. indonesian journal on geoscience, 1(1), 9–19. https://doi.org/10.17014/ijog.v1i1.172. kohn, m. j. (2014). himalayan metamorphism and its tectonic implications. annual review of earth and planetary sciences, 42(1), 381–419. https://doi.org/10.1146/annurev-earth060313-055005. kurnianto, f a, & nurdin, e. a. (2020). analysis of stratigraphy and lithology in forming gold minerals in east java with digital elevation model and medium format photo. iop conf. ser.: earth environ. sci, 485, 12145. https://doi.org/10.1088/17551315/485/1/012145. kurnianto, fahmi arif, apriyanto, b., nurdin, e. a., ikhsan, f. a., & fauzi, r. bin. (2018). geographic information system (gis) application to analyze landslide prone disaster zone in jember regency east java. geosfera indonesia, 2(1), 45. https://doi.org/10.19184/geosi.v2i1.7524. lanari, p., ferrero, s., goncalves, p., & grosch, e. g. (2019). metamorphic geology: progress and perspectives. in geological society special publication478(1), 1–12. https://doi.org/10.1144/sp478-2018-186. lewerentz, a. (2017). fluid-induced alteration of metasedimentary rocks in the scottish highlands. dissertation, geology, stockholm university. retrieved from https://www.diva-portal.org/smash/get/diva2:1135383/fulltext01.pdf. maulana, a., jaya, a., & sitha, k. (2018). field characteristic of metamorphic-hosted gold deposit in sulawesi, indonesia: an insight into awak mas prospect, south sulawesi. international journal of engineering and science application, 4(2), 105–112. http://pasca.unhas.ac.id/ojs/index.php/ijesca/article/view/1385. moniruzzaman, m., alamgir, m., chowdhury, z., rahman, m. a., sulaiman, s. a., & gan, s. h. (2014). determination of mineral, trace element, and pesticide levels in honey samples originating from different regions of malaysia compared to manuka honey. biomed research international, 2014(359890), 1–10. 266 m. musnajam et al / geosi vol 5 no 2 (2020) 250-267 https://doi.org/10.1155/2014/359890. nelson eby, g., charnley, n., pirrie, d., hermes, r., smoliga, j., & rollinson, g. (2015). trinitite redux: mineralogy and petrology. american mineralogist, 100(2–3), 427–441. https://doi.org/10.2138/am-2015-4921. noor, m. k., tonggiroh, a., & maulana, a. (2016). type of gold hydrothermal deposits on metamorphic rock district buru, province maluku. international journal of engineering and science applications, 3(1), 39–45. http://pasca.unhas.ac.id/ojs/index.php/ijesca/article/view/276. nugraha, a. m. s., & hall, r. (2018). late cenozoic palaeogeography of sulawesi, indonesia. palaeogeography, palaeoclimatology, palaeoecology, 490, 191–209. https://doi.org/10.1016/j.palaeo.2017.10.033. nursalam, l. o., arisona, a., harudu, l., harianto, e., & kasmiati, s. (2019). mapping of subsurface geological structure and land cover using microgravity techniques for geography and geophysic surveys : a case study of maluri park , malaysia. geosfera indonesia, 4(3), 280–290. setiawan, n. i., osanai, y., nakano, n., adachi, t., & asy’ari, a. (2015). metamorphic evolution of garnet-bearing epidote-barroisite schist from the meratus complex in south kalimantan, indonesia. indonesian journal on geoscience, 2(3), 139–156. https://doi.org/10.17014/ijog.2.3.139-156. singh, p. k., singh, m. p., singh, a. k., naik, a. s., singh, v. k., singh, v. k., & rajak, p. k. (2012). petrological and geochemical investigations of rajpardi lignite deposit, gujarat, india. energy exploration & exploitation, 30(1), 131–151. https://doi.org/10.1260/0144-5987.30.1.131. soesilo, j., schenk, v., suparka, e., & abdullah, c. i. (2015). the mesozoic tectonic setting of se sundaland based on metamorphic evolution. proceedings indonesian petrolium association. http://archives.datapages.com/data/ipa_pdf/2015/ipa15-g-205.htm. song, i., & suh, m. (2014). effects of foliation and microcracks on ultrasonic anisotropy in retrograde ultramafic and metamorphic rocks at shallow depths. journal of applied geophysics, 109, 27–35. https://doi.org/10.1016/j.jappgeo.2014.07.011. surono. (2013). geologi regional sulawesi tenggara. badan geologi kementerian energi dan sumberdaya mineral. retrieved from https://www.academia.edu/35832171/geologi_regional_sulawesi_tenggara?auto=dow nload. tóth, t. m., & schubert, f. (2018). evolution of the arc-derived orthogneiss recorded in exotic xenoliths of the körös complex (tisza megaunit, se hungary. journal of geosciences (czech republic), 63(1), 21–46. https://doi.org/10.3190/jgeosci.253. usda. (2012). geology national engineering handbook chapter: engineering classification of rock materials.washington dc: united states department of 267 m. musnajam et al / geosi vol 5 no 2 (2020) 250-267 agriculture, natural resources conservation service. xu, h., hill, t. r., konishi, h., & farfan, g. (2017). protoenstatite: a new mineral in oregon sunstones with “watermelon” colors. american mineralogist, 102(10), 2146–2149. https://doi.org/10.2138/am-2017-6186 2. methods 92 p.i. ifabiyi et al / geosi vol 5 no 1 (2020) 92-105 water poverty assessment in olorunsogo local government area of oyo state, nigeria p.i. ifabiyi1, b. oladele 1 , and salau wahab2* 1department of geography and environmental management, faculty of social sciences, university of ilorin, pmb 1515, ilorin, nigeria 2department of geography, faculty of humanities, management and social sciences, federal university of kashere, pmb 0182, gombe state, nigeria *corresponding author : salawiy@fukashere.edu.ng received 12 august 2019/ revised 21 december 2019/ accepted 5 january 2020/ published 10 april 2020 abstract poor access to water is often linked to poverty, human welfare, health, nutritional status, and household labour. this paper is aimed at contributing to the debate surrounding water poverty in the rural areas. primary data obtained covering water resources, access, capacity, uses, and environment were collected using closed-ended questionnaires. altogether, 370 household heads were sampled and were selected by systematic random sampling technique. multiple correlations, factor analysis and multiple regression methods were used to determine the level of relationship between the water poverty index (wpi) components. the results revealed that: wpi is the highest in elenke/sagbo (72.3%) and the lowest in onigbeti ii/sagbon (55.5%). also, wpi has a strong positive relationship with resources (r = .656), capacity (r = .705) and environment at 95%. percentages of explanations of wpi ranges from 86.45% in onigbeti i to 50.99% in aboke.the results of multiple regression between wpi and components showed that components were weak predictors in 5 wards (onigbeti iii &iv, onigbeti ii , onigbeti i, seriki agbele aboke and abogun wards). the paper posits that access to water in olorunsogo local government area (lga) is generally reasonable. the paper suggests stronger government presence to improve and sustain the level of access. keywords : water poverty; access; capacity; uses; environment; resources; factor analysis 1. introduction in 2002, the united nations development programme (undp) ranked nigeria as the 26th poorest nation in the world. a relevant poverty type in nigeria is that of water. waterrelated poverty emerges when water resources constrain or impact upon people’s livelihood options and assets. water poverty arises as a result of inadequate availability of water or lack of proper accessibility to potable water for man’s use and consumption. water itself is an essential geosfera indonesia p-issn 2598-9723, e-issn 2614-8528 vol.5 no. 1 (2020), 92-105, april, 2020 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v5i1.13438 accredited by the ministry of research , technology , and higher education of the republic of indonesia, no. 30/e/kpt/2019. mailto:salawiy@fukashere.edu.ng https://jurnal.unej.ac.id/index.php/geosi https://drive.google.com/file/d/1rsnvas6cuhowhl5bj87cl2l6k5dqz7s6/view 93 p.i. ifabiyi et al / geosi vol 5 no 1 (2020) 92-105 resource to man and it takes up a vital role in everyday activities of man. it is of great importance for domestic, cultural and various industrial uses. it harbors various life forms which are generally classified as hydrophytes and aquatic animals. according to the world health organization (who), a person requires roughly 25 liters of water per day to promote healthy living. with man’s ever demanding attitude for water and other climatological factors, the supply of water has drastically reduced over the years. this tends to exert stress on the available water resources. in other words the available water may become insufficient for the demanding population. this could be a result of the increase in human population. water poverty is measured by the water poverty index (wpi) (falkenmark et al., 1989; sullivan, 2002; ifabiyi & ogunbode, 2004; falkenmark & rockstron, 2004; heideck, 2006; fenwick, 2019). water poverty tends to prevail in developing and less developed nations of the world where there are improper management of water in supply, usage and recycling. water scarcity; may results in environmental, agricultural, and various economical and health issues. the finite nature of renewable fresh water makes it critical to examinenatural resources in the context of population growth. as population grow, the average amount of renewable fresh water available to each person declines. hence, hydrologists and other water experts agree that when certain ratios of water stress and outright scarcity are all but inevitable, then the population is heading towards water poverty. water poverty has various implications on national development. in nigeria, studies of water supply are mainly focused on water supply and demand with little emphasis on water scarcity and water poverty (ifabiyi & ogunbode, 2014) despite the fact that water scarcity has already been widely experienced. spatial and temporal analysis can reduce the potential for water poverty in certain areas (kallio et al., 2018). precipitation index, vegetation condition index, and soil moisture content index affect the potential for drought in an area (mohmmed et al., 2018). water quality can affect the health and welfare of the community in the long term (borgomeo et al., 2018). one of the government policies that greatly influences the development of settlements in cities is by displacing settlements that are unable to provide access to quality water (davis & ryan, 2017). developing countries need to pay attention to the distribution of clean water in each region due to its vulnerability to poverty aspects. the above studies do not discuss the relationship between the water poverty index, resources, access, 94 p.i. ifabiyi et al / geosi vol 5 no 1 (2020) 92-105 capacity, uses and environment in a comprehensive manner. it is crucial to conduct this study due to the fact that community needs related to clean water are not only related to physical aspects, but also often related to social problems. access and capacity are novel aspects to study and relate to aspects of nature and the environment. this study is aimed at contributing to the debate surrounding water poverty in rural areas. 2. area of study olorunsogo local government is located in the northern part of oyo state, nigeria. its coordinates are lat 8°45 ‘0’’n and long 4°7 ‘0’’e. it is one of the 33 local governments in oyo state nigeria. its headquarters is in the town of igbeti. it has an area of 1,069 m2 and a population of 81, 759 at the 2006 census. it has 10 wards as shown in the table 1. table 1. list of wards in olorunsogo local government area the climate of the area is characterized by dry and wet seasons with high relative humidity. dry season is between novembermarch while the wet season starts from april and ends in october. average daily temperature ranges between 25°c (77.0°f) and 35°c (95.0°f) almost throughout the year. precipitation varies from an average of 1200mm. however, during the wet season,high surface runoff with high humidity usually occurs. this study area has the guinea savannah vegetation type. aquifers are of restricted vertical and lateral extent, but since the tropical climate affords the necessary conditions for deep and rapid chemical decay, thick, sandy clayey, lateritic overburdens serve as potential aquifers.this area is underlain by metamorphic rocks of the basement complex, which outcrop over many parts. geographical features such as the iyamopo and the agbele hill are the dominant relief systems. rocks consist s/n name i. aboke ( aboyunogun) ii.. apataalaje iii. elenke/ sagbo iv. ikolaba/ obadimo v. onigbeti i vi. onigbeti ii/ sagbon vii. onigbeti iii & iv viii. opa/ ogundiran ix. seriki i & (abosino) x. seriki ii & (agbele) 95 p.i. ifabiyi et al / geosi vol 5 no 1 (2020) 92-105 of old hard rocks and dome shaped inselberg hills, which gently rise from about 500metres in the southern part and reaching a height of about 1,219metres above sea level in the northern part around igbeti town. the local government area has been regarded as suitable for agricultural purposes. igbeti has a large food market with marketers from every part of nigeria. market products include: yam, yam flour and cassava flour. a large proportion of the residents engage in agriculture either in small or in large scale. the extensive marble deposit in igbeti led to the presence of the nigerian mining company limited in1984. quarrying is also a prominent activity in the lga. tourism is also an important activity due to the prominent hills and the old oyo national park which extend to ogundiran area of olorunsogo local government area. figure 1. igbeti and environs 96 p.i. ifabiyi et al / geosi vol 5 no 1 (2020) 92-105 3. methods data used in this study were collected by structured questionnaires. data were sourced from the 10 political wards in olorunsogo local government area of oyo state. these include: information on water availability, accessibility to water supply, capacity of water resources, water use and environment. online sample size calculator was used to determine the total number of questionnaires to be administered after estimating the population size using equation 1. pn= po (1+r/100) x (1) where: po= population size (according to the 2006 census figure) r = population growth rate x = number of years (2015-2006) = 9 years pn = 81,759 (1+34/100) 9 pn = 81,759 (1+0.34) 9 pn = 110,465 with the population figure of 110,465 and a household size of 8, the krejice and morgan sample size calculator arrived at the use of 370 questionnaires with 37 copies of questionnaires for each of the 10 wards in the lga. a closed ended questionnaire was used in which the respondents were allowed to choose from the available options only. systematic random sampling technique was adopted to select respondents in the 10 wards. accessibility to water can be quantified by using several indicators such as: human development index, water supply stress index, population growth impacts of water resource availability, e.t.c. out of the above indices, the water poverty index (wpi) was used because it is found to be the most effective tool to access water availabilit y of the regions. wpi is easy to calculate, easy to implement and is mainly based on the existing data. water poverty index (wpi) as defined by sullivan et al. (2002) is mathematically defined as: 97 p.i. ifabiyi et al / geosi vol 5 no 1 (2020) 92-105 𝑊𝑃𝐼= 𝑊1×𝑅 + 𝑊2×𝐴 + 𝑊3×𝑈 + 𝑊4× 𝐶 + 𝐶5×𝐶 (2) 𝐶1+𝐶2+𝐶3+𝐶4+𝐶5 the weights (𝑊i) applied to each of the five components (𝑅,𝐴,𝐶,𝑈&𝐸) are constrained to be non-negative and sum to unity. all parameters are standardized to fall in the range of 0-1, where value 0 is assigned to the poorest level (i.e highest degree of water poverty), and 1 to optimum conditions. the wpi defines water poverty according to the five components, i.e.: resources, access, capacity, use and environment. 4. results and discussion 4.1 components of water poverty the score of resources in this study`is 87.6% in elenke /sagbo ward, suggesting that the ward had more than one sources of water. the lowest availability was in apata /alaja ward with limited sources of water. generally, the lga had reasonable score on resources with all the wards scoring above 50%. rain fell for a minimum of 7 months. access to water was the highest in apata/alaje with a score of 89.3% and the lowest in seriki ii with 50%. all wards scored above 50%. there were many hand dug wells in this ward. capacity was at its highest score in elenke/ sagbo ward (67.6%). this was an expected result due to the significant number of employed people in this ward. capacity scored above 50% in all the political wards. uses of water had the highest score in ikolaba/obadimo ward. this was expected in view of the fact that water was used in this ward for block making and other cottage industrial uses. the lowest value of 40% was recorded in onigbeti/sagbon ward. uses of water were largely domestic in the lga. aboke/aboyun-ogun had a score of 87.1%, which was the highest value; the lowest value was in onigbeti ii/ sagbon ward. environment plays a dominant role in water supply as it is responsible for sustaining river flow and groundwater level. 98 p.i. ifabiyi et al / geosi vol 5 no 1 (2020) 92-105 figure 2. pattern of distribution of water poverty components in the political wards: water poverty pattern 0 50 100 aboke/aboy un ogun apata alaje elenke/ sagbo ikolaba/ obadimo onigbeti i onigbeti ii/ sagbon onigbeti iii & iv opa/ ogundiran seriki i & (abosino) seriki ii & (agbele) figure 2 (a): resources 0 50 100 aboke/aboy … apata alaje elenke/ sagbo ikolaba/ … onigbeti i onigbeti ii/ … onigbeti iii … opa/ … seriki i & … seriki ii & … figure 2 (b) access 0 50 100 aboke/a… apata… elenke/… ikolaba/… onigbeti i onigbeti… onigbeti… opa/… seriki i &… seriki ii… figure 2 (c ): capacity 0 50 100 aboke/a… apata… elenke/… ikolaba/… onigbeti i onigbeti… onigbeti… opa/… seriki i &… seriki ii… figure 2 (d) uses 0 50 100 aboke/aboyu… apata alaje elenke/ sagbo ikolaba/… onigbeti i onigbeti ii/… onigbeti iii &… opa/… seriki i &… seriki ii &… figure 2 (e): environment 99 p.i. ifabiyi et al / geosi vol 5 no 1 (2020) 92-105 figure 2 depicts the patterns of wpi from aboke/ aboyunogun ward to seriki ii & agbele ward of the local government area. water resources were the highest in elenke/ sagbo with 87.6% and lowest in apataalaje (53.1%). water was most accessible in apata alaje (89.3%) and least accessible in seriki (abosino). capacity was the highest in elenke/ sagbo and lowest (53.8%)in serikiabosino. water use was the highest in ikolaba/obadimo ward with (61.2%) and lowest in onigbeti ii/ sagbon with 40%. the environment was clean and free from most environmental challenges with the highest value in aboke/aboyun ogun (87.1%) and lowest in onigbeti ii/ sagbon with 51.9%. on the values of wpi, elenke/ sagbo was the highest (72.3%), while onigbeti ii/sagbon ward was the lowest with 55.5%. the value recorded in this study was relatively higher than the value of 44% obtained as the national value for nigeria and was higher than that of many african nations (egypt=28.71%, niger= 44%, ghana=47.50%, south africa=41.51%) but lower than that of some other countries (equatorial guinea =87.99%, gabon 78.15%, angola=65.86%, etc). the value range was medium to low, indeed none of the communities had severe water poverty situation (table 3). this suggests that the level of scarcity is not severe. water resources is generally relatively available. the values recorded in table 3 showed that there was reasonable access to water in the lga as no ward had less than 55% access. this feat was made possible as a result of government intervention in water provision and due to the numerous hand-dug wells which was common to almost every household. igbeti lga is situated within interfluves with relatively rich, shallow regolith aquifer, which supply water reasonably to shallow wells. in addition to this, government also provided a number of hand pumps and motorized boreholes within the various communities in the study area. hence, this had alleviated the burden of water scarcity. 100 p.i. ifabiyi et al / geosi vol 5 no 1 (2020) 92-105 figure 3. pentagrams representation of the wpi in olorunsogo local government area 63.7 59.6 6652.5 87.1 0 50 100 resources access capacityuses environ… fig 3 (a) wpi of aboke/aboyun-ogun 53.1 89.3 62.654 68.8 0 50 100 resources access capacityuses environment fig 3 (b): wpi of apata alaje 64.7 71 59.661.2 63.1 40 60 80 resources access capacityuses environment fig 3 (d) wpi of ikolaba/ obadimo 57 57 61.4 43.6 77.3 0 50 100 resources access capacityuses environment fig 3 (e) wpi of onigbeti i 56.1 69.3 60.2 40 51.9 0 50 100 resources access capacityuses environm ent fig 3 (f) wpi of onigbeti ii 54.2 55.6 63.654.8 80.6 0 50 100 resources access capacityuses environment fig 3 (g) wpi of onigbeti iii & iv 60.6 64.3 61.443.5 86.4 0 50 100 resources access capacityuses environment fig 3 (h) wpi of opa ogundiran 65.8 50 53.856.6 69.7 0 50 100 resources access capacityuses environme nt fig 3 fig 2 (i) wpi of seriki abosino 60.8 62.7 59.148.5 53.4 0 50 100 resources access capacityuses environme nt fig 3 (j) wpi of seriki ii &agbele 64.7 71 59.661.2 63.1 50 60 70 80 resources access capacityuses environment fig 3 (c) wpi of elehike/sagbo 101 p.i. ifabiyi et al / geosi vol 5 no 1 (2020) 92-105 4.2 the relationships between wpi, resources, access, capacity, uses and environment as indicated in table 2, the relationship between wpi and its five components (resources, access, capacity, uses and environment) were used to calculate water poverty. wpi has a strong positive relationship with resources (r = .656), capacity (r = .705) and environment (r = 0.683) which are statistically significant at 95% confidence level, this suggest that as resources, capacity and environmental factor increases in the study, wpi also increases. on the other hand, wpi has a weak and mild positive relationship with access (r = .240) and uses (r = .566) respectively which were not statistically significant at 95% confidence level. however, access has a weak negative relationship with resources (r = -.215) and environment (r = -.289) but the relationships are not statistically significant at 95% confidence level. ever y component exhibits weak positive relationship with each other. the weak relationship between the wpi and water accessibility can be explained by the distance to the source of water and the household size. these two factors have a high magnitude of association with access (r = .240) in the study area. resource availability in the study area is also high as farming activities take place within the local government and this enhances the trading activities which includes foreigners from several parts of the country. trade itself is a catalyst to economic growth and this has led to the provision of infrastructural facilities which include water supply in the study area. water usage or water demand in the study area is about 70% of the availability. about 74% of this is diverted for agricultural use while the remaining 26% is accountable for domestic, industrial recreational, commercial, and other uses. table 2. relationship between wpi, resources, access, capacity, uses and environment components resources access capacity uses environment wpi .656* .240 .705* .566 .683* resources -.215 .321 .422 .340 access .214 .033 -.289 capacity .051 .589 uses .173 102 p.i. ifabiyi et al / geosi vol 5 no 1 (2020) 92-105 table 3. water poverty index (wpi) of olorunsogo local government area ward resources access capacity uses environment wpi aboke/aboyun ogun 63.7 59.6 66 52.5 87.1 65.7 medium low apata alaje 53.1 89.3 62.6 54 68.8 65.6 medium low elenke/ sagbo 87.6 63.6 67.4 56.9 85.8 72.3 low ikolaba/ obadimo 64.7 71 59.6 61.2 63.1 63.9 medium low onigbeti i 57 57 61.4 43.6 77.3 59.3 medium onigbeti ii/ sagbon 56.1 69.3 60.2 40 51.9 55.5 high onigbeti iii & iv 54.2 55.6 63.6 54.8 80.6 61.8 medium low opa/ ogundiran 60.6 64.3 61.4 43.5 86.4 63.2 medium low serikii & (abosino) 65.8 50 53.8 56.6 69.7 59.2 medium seriki ii & (agbele) 60.8 62.7 59.1 48.5 53.4 56.9 medium table 4. determinants of water poverty in olorunsogo lga political wards multiple regression properties factor % regression factor analysis % regression % aboke/ aboye access nil 54.99 31.71 apata alaje capacity (31.71) resources (29.81) resources (76.4) capacity(5) 61.53 82.0 ikolaba/obadimo usage (34.88) environment (23.70) environment (50) 58.58 50.0 onigbeti i i. resources (35.24) access (29.1) capacity (22) resources (41.0) 86.45 41.0 onigbeti ii environment capacity environment capacity 65.28 2.90 onigbeti iii & iv resources usage usage resources 65.28 2.90 ogunderin/opa resources access usage resources usage 77.70 96.5 seriki/abiso usage access usage 56.80 56.4 seriki/ agbele environment resources capacity 79.88 17.2 elenko/sagbo resources access resource access 68.82 99.2 103 p.i. ifabiyi et al / geosi vol 5 no 1 (2020) 92-105 the indices of water poverty differ in their dominance from ward to ward. as shown in table 4. the resources had the highest rate of reoccurrence (6 times), access appeared 5 times, capacity and water uses featured 4 times, while environment featured only 3 times.this distributionsupportsthe relatively fair pattern of water access whereby at least all lgas had wpi of greater than 50%. meanwhile, the percentages of explanation were generally strong, ranging from 86.45%in onigbeti i to 50.99% in aboke. previous studies discovered that, among others, community social status influences access and management to clean water (ngarava et al., 2019), investment growth can affect the expansion of settlements in coastal areas and have an impact on water quality degradation (hoque et al., 2019), land use for agriculture is more optimal when carried out in rural areas with consideration of market access and better water availability (harmanny & malek, 2019), the majority of the poor finds it difficult to access clean water pipes due to cost issues (carrard et al., 2019),increasing the ability of the community to manage water resources is needed to reduce social barriers in the use of clean water (panthi et al., 2019). meanwhile, this study found the role of access and capacity of the community in reducing the potential for lack of clean water. the results of this study shows that access to clean water is not only related to natural conditions such as aquifers, but also related to the ability of governments and communities to manage clean water. providing access to the community does not only take the form of water infrastructure development, but also reduces prices to access the water infrastructure. the relationship between wpi and component was slightly different in many wards, such as onigbeti iii &iv, onigbeti ii , onigbeti i, seriki agbele aboke and abogun. the components of wpi, provided weak explanations, suggesting that in these wards, access to water may be due to other reasons such as politics, culture, technology, and other variants which are beyond the scope of this papers. however, in the other 5 lgas, wpi were better predictors of water access. 5. conclusion water supply in the study area was adequate; therefore, there was low level of water scarcity in the study area. the results revealed that: wpi was the highest in elenke/sagbo (72.3%), wasthe lowest in onigbeti ii/sagbon (55.5%).this supportedthe relatively high pattern 104 p.i. ifabiyi et al / geosi vol 5 no 1 (2020) 92-105 of water access, whereby at least all lga had wpi of greater than 50%. the paper posits that access to water in olorunsogo lga was generally reasonable and that the impacts of wpi differed from ward to ward as certain variables were dominant in certain ward compared to the others. the paper suggests stronger government presence to improve and sustain the level of access and poverty margin. conflict of interest the authors declare that there is no conflict of interest with any financial, personal, or other relationships with other people or organizations related to the material discussed in the article. references borgomeo, e., hall, j. w., & salehin, m. (2018). avoiding the water-poverty trap: insights from a conceptual human-water dynamical model for coastal bangladesh. international journal of water resources development, 34(6), 900-922. doi:10.1080/07900627.2017.1331842 carrard, n., madden, b., chong, j., grant, m., nghiêm, t. p., bùi, l. h., . . . willetts, j. (2019). are piped water services reaching poor households? empirical evidence from rural viet nam. water research, 153, 239-250. doi:10.1016/j.watres.2019.01.026 davis, m. f., & ryan, n. (2017). inconvenient human rights: water and sanitation in sweden’s informal roma settlements. health and human rights, 19(2), 61-72. falkenmark, m. and rockström, j. (2004).balancing water for humans and naturethe new approach in ecohydrology.london: earth scan. falkenmark, m., lundqvist, j., &widstrand, c. (1989).macro-scale water scarcity federal republic of nigeria (2000), water supply and sanitation interim strategies note fenwick, c. (2019). identifying the water poor: an indicator approach to assessing poverty in rural mexico. a phd thesis submitted to department of civil, environmental and geomatic engineering, university college, london. pg. 270. guppy, l. (2014) the water poverty index in rural cambodia and vietnam: a holistic snapshot to improve water management planning. natural resources forum. 38: 203-219 harmanny, k. s., & malek, ž. (2019). adaptations in irrigated agriculture in the mediterranean region: an overview and spatial analysis of implemented strategies. regional environmental change, 19(5), 1401-1416. doi:10.1007/s10113-019-01494-8 105 p.i. ifabiyi et al / geosi vol 5 no 1 (2020) 92-105 hoque, s. f., hope, r., arif, s. t., akhter, t., naz, m., & salehin, m. (2019). a socialecological analysis of drinking water risks in coastal bangladesh. science of the total environment, 679, 23-34. doi:10.1016/j.scitotenv.2019.04.359 ifabiyi i.p. & ogunbode t. o. (2014): the use of composite water poverty index in assessing water scarcity in the rural areas of oyo state nigeria. an international journal of science and technology, 3 (2):51-65. kallio, m., guillaume, j. h. a., kummu, m., & virrantaus, k. (2018). spatial variation in seasonal water poverty index for laos: an application of geographically weighted principal component analysis. social indicators research, 140(3), 1131-1157. doi:10.1007/s11205017-1819-6 kini, j. (2017). inclusive water poverty index: a holistic approach for helping local water and sanitation services planning. water policy, 19(4), 758-772. doi:10.2166/wp.2017.075 maheswari, j.u. & chaithanya, s.m. (2015) water poverty index facts and figuresa review. international civil engineering symposium. doi: 10.13140/rg.2.13681.1369. mohmmed, a., zhang, k., kabenge, m., keesstra, s., cerdà, a., reuben, m., . . . ali, a. a. s. (2018). analysis of drought and vulnerability in the north darfur region of sudan. land degradation and development, 29(12), 4424-4438. doi:10.1002/ldr.3180 ngarava, s., zhou, l., & monde, n. (2019). gendered water insecurity: a structural equation approach for female headed households in south africa. water (switzerland), 11(12) doi:10.3390/w11122491 panthi, j., khatiwada, k. r., shrestha, m. l., & dahal, p. (2019). water poverty in the context of climate change: a case study from karnali river basin in nepal himalaya. international journal of river basin management, 17(2), 243-250. doi:10.1080/15715124.2018.1531421 sullivan, c. (2002), calculating a water poverty index. world development journal, 30 (7): 1195-1210. umamahheswari, j., bukke, s. & chaithanya, s.m. (2017) water poverty index as a water management :a micro level study in tamil nadu, india. a paper presented 6thconference on water and food management (icwfm, 2017) research article rethinking urbanization: a transit-information-communication –technology-oriented development path for the developing countries and post-industrial towns schuman lam*, heng li , ann t.w. yu department of building and real estate, the hong kong polytechnic university, block z, hung hom, kowloon, hong kong received 24 november 2020/revised 21 march 2021/accepted 28 march 2021/published 25 april 2021 abstract this study explores a new path of urbanization to enhance the conventional economy-led urban development practice by conducting an urban quality of life (uqol) survey. it analyzes the uqol evaluation gap caused by demographic attributes between developing countries, developed countries, and post-industrial town. we adopted a mixed-methods research design, including a literature review and an uqol survey, to suggest the transit-oriented-development (tod) and information-communication-technology (ict) based urban-rural development concept. the finding indicates a disparity of uqol mean score rankings among the developing countries, developed countries, and the marginalized post-industrial town. it highlights the health, transportation, socio-economic, and technological development in the developing countries strongly desired. furthermore, kruskal-wallis h-test and mann-whitney u-test results show significant differences in economy, technology-ict, smart living, and lifestyle within education, profession, age, and country groups. it clarifies that the well-being gap is shaped by demography and exhibited geographically, which implies tod-ict advancement can break down geographical barriers for achieving sustainable growth in remote areas. supported by the planetary urbanization theory, the human-technology-driven urban development process would facilitate the maturity and implementation of the proposed todict-based urban-ruralism (uxr) concept for enhancing the future global urbanization process. keywords : human and social geography; information-communication-technology; urban policymaking; transit-oriented-development; urban quality of life 1. introduction nowadays, pressing global urban issues caused by overdevelopment appeals to practical solutions. unsustainable urban development policy driven by industrialization and adopted by the developed countries has been proved to be the due cause (club of rome, 2018). economy-led industrialization and urbanization have been reshaping our urban landscape in both the developed and the developing countries of the world (unicef, 2020) geosfera indonesia *corresponding author. email address : 14900559r@connect.polyu.hk (schuman lam) 1 vol. 6 no. 1, april 2021, 1-19 p-issn 2598-9723, e-issn 2614-8528 https://jurnal.unej.ac.id/index.php/geosi doi : 10.19184/geosi.v6i1.20810 http://orcid.org/0000-0002-3187-9041 mailto:14900559r@connect.polyu.hk 2 schuman lam et al. / geosfera indonesia 6 (1), 2021, 1-19 with an impressive record of economic growth while causing damage to other aspects of urban quality of life (uqol) and the ecological environment (dong et al., 2016). regarding the urban problems left from industrialization we are all facing, world leaders and policymakers must rethink their urban development roadmap to improve their citizens' livelihoods while preserving enough resources to accommodate the next generations' needs. in developing countries, where most of their bare landscapes are yet for development, the kind of sustainable development path adopted by the developing countries in asia and africa is extremely critical to the fight against climate change and degradation of living quality. thus, the ways of life preferences of people from these regions become the primary study for policymakers and this study's vital task. climate change and a series of urban problems are the adversaries and predicament affecting people's well-being. for a long time, every government has tried to tackle the problems by designing and implementing the needed urban policies. unfortunately, their effort has not been paid off because the rhetoric approach lacks flexibility and operability. although the general definition of uqol would be pure rhetoric to understand, its implication on government policies considering individual needs must be evaluated and communicated among the stakeholders effectively because the uqol evaluation result can inform policymakers and planners the essential information to build and manage the city in a sustainable manner (marans, 2015). the relationship between quality of life evaluation, industrialization-urbanization, and sustainable urban development (sud) determines uqol survey location: developing countries, developed countries, and developed post-industrial mirafiori town. quality of life (qol) is a critical topic in urban development due to its function in monitoring public policies as a useful tool (rezvani et al., 2013). however, its multi-faceted and quite inter-disciplinary subjective nature makes it challenging to understand and evaluate the real meaning comprehensively and precisely for mutual communication and cooperation among the stakeholders. the study of qol started in the usa in the 30s. in the social indicator movement period, chicago school began to study qol by mixing social science and geography (mikkelsen & di nucci, 2015).then the realization of objective indicators as the measurement of qol was in its maturity in the 60s, which was expanded to include the disciplines of politics, economics, geography, planning, architecture, environmental studies, psychology, medicine, education, and others (mikkelsen & di nucci, 2015), but not much in the field of sustainable urban development (sud). in this period, a top-down policy-driven approach for studying and evaluating qol centered around economic development was adopted: objective indicators like gdp, employment data, mortality and morbidity rate, and 3 schuman lam et al. / geosfera indonesia 6 (1), 2021, 1-19 crime rates have been used to evaluate qol because living conditions and standard of living to the implementation of economic and social policies were the new approaches to study qol (land et al., 2012). between the 1970s and 1980s, qol became a multi-dimensional concept, including other dimensions of human life (rodriguez, 2015). in the past 20 years, a resurgence of the qol study movement was driven by the research community (academic and private), city government, and world institutions (marans & stimson, 2011), especially by public policy, urban governance, planning, and management, and sustainable development for enhancing uqol (mccrea et al., 2006). many of the studies were nation or city ranking reports mainly driven by economic growth to serve the capital-led development trajectory. in the 1990s-2010s, there was the advocacy of establishing a more comprehensive mechanism (top-down policy-driven and bottom-up subjective-well-beingsurvey swbs) for studying qol by (diener, 1995; marans & kweon, 2011). still, the research market on the direct link of qol and sud is missing. more research on (qol + sud = uqol) in both qualitative and quantitative studies should be encouraged, while sud has been well advocated by the world institutions such as united nations (un) and world commission on environment and development (wced, 1987) because sud aims for uplifting qol. until the 2010s onward, there were different types of qol ranking reports attending to evaluate people's well-being and livelihoods in the context of mobility, sustainability, happiness, social progress, and technology. the uqol evaluation criteria refer to them as the base to develop the 11 uqol indicators (health, environment, mobility, governance, human capital, social, economy, technology-ict, culture, smart living, and lifestyle) to examine the uqol evaluation gap shaped by demographic and geographical attributes. as per the world health organization (dan bar-on, 1995), quality of life (qol) is individual perceptions related to their position based on the character of cultural background and values in life and life goals. their value systems have been influenced by the demographic and geographical background of the urban environment they lived in (campbell, 1976; marans & stimson, 2011; potter et al., 2012; murgaš & klobučník, 2018). wilson & jonas (2018) described that urbanization is the interface to glue the multi-layers of ways of life, from the internal thoughts to the external political, social, economic, and physical morphologies. this notion expresses that urbanization is not a form and can be interpreted as a human development process or movement, interpreted by human geography. thus, the debating planetary urbanization theory was adopted as the theoretical base to start the exploratory study. in such a notion, we argued that there are evaluation gaps between the developing countries, developed countries, and developed post-industrial towns; thus, the conventional economy-led urbanization 4 schuman lam et al. / geosfera indonesia 6 (1), 2021, 1-19 roadmap needs to be updated for securing the sustainable growth of our planet (the sustainability development goals aim to fight poverty and hunger, confront the climate crisis, achieve gender equality, and much more). the study was motivated by the sustainable development goals (united nations, 2020) advocated by the united nations. the 2-degree celsius threshold line set by the previous paris agreement (unfccc, 2016) in fighting climate change has not been materialized to deepen the fault further, rapid industrialization and urbanization in asia and africa where the developing countries are playing catch up in economic development. the performance of environmental sustainability depends on the people's engagement, particularly at the local level; mutual understanding and cooperation are needed to achieve the climate change goal set by the paris agreement. as problems accumulate faster than the solution, the evolutionary transition to a new urban development paradigm becomes necessary. we believed that a new study approach, systems, and tools enabling the transformation from a synergistic one should be explored. urbanization is a dynamic-adaptive-complex system bred in constant mutation with unique local characteristics, not a simple generic organism. since the industrial period, urbanism is being reproduced and remade worldwide according to which trajectory has been laid by capitalism (brenner & schmid, 2015). in the digital period, should we keep on walking along the same development path adopted by the developed countries? to locate a new future sustainable urban development path, we need to understand the composition of perceived uqol subject to the roles of demographic and geographical groups and then envisage the feasible route to reach the sustainable development goals. given the previous literature review regarding sustainable urban development, quality of life, and planetary urbanization, the mismatch of the human condition (value/demand) and the offering/supply of global urbanism require local investigation to redefine and refine the claim by brenner & schmid (2015), which the evaluation of uqol can contribute to the task. thus, we conducted an uqol survey to analyze and interrogate the hypothesis of the "urban quality of life (uqol) evaluation gap is caused by subjective demographic and geographical attributes in shaping the urban landscape." based on the debatable planetary urbanization theory. for a long time, gdp has been the de facto quality of life indicator for evaluating uqol in terms of economic growth alone due to market need. however, a few researches focused on studying the interrelationship of sud and qol and their undeniable role in urban policymaking. the gap between the subjective well-being and sustainable requests must be compromised through implementing a different urban development path addressing uqol beyond economic growth. this research intends to explore a new human-oriented 5 schuman lam et al. / geosfera indonesia 6 (1), 2021, 1-19 development concept to merge the well-being gaps between the developed and developing countries for reaching global sustainability. the objectives of this research are: (1) to present and discuss the uqol evaluation gap between the concerned geographical domains; (2) to locate the independent groups contributing to the uqol evaluation by examining the relationship of demographic attributes to geographical domains in ranking the well-being indicators; (3) to predict future sustainable urban development needs by analyzing the uqol mean score significant differences among the different categories of education, profession, age, developing countries, and developed countries. by comparing and discussing the relationship of urban development and various aspects of urban life requests at the community and country levels, the study provides the rationale to develop a novel tod-ict-based urban-ruralism (uxr) development concept for merging the well-being gap between the urban and rural areas and the developing and developed countries. 2. methods 2.1 research design a mixed-methods research design started with a literature review to state the motivation, evaluation gap, the theory-based argument, and the objectives for fulfilling the overall aim, validated by the data collected from an uqol survey. convenient sampling was conducted via online and offline channels for six months in 2018-19. ibm spss statistics 20 english version software was hired to run the raw data collected from the survey. the mean score (ms) test and the non-parametric kruskal-wallis h-test and mann-whitney u test produced the quantitative results. we conducted descriptive statistics, cronbach’s alpha reliability test, normality test, non-parametric ms tests to generate the scientific results. first, the cronbach’s alpha reliability test (likert scale bigger than 0.7) justified that the chosen scale was suitable, the data collection instrument was strongly reliable, and the responses were consistent with the survey to reduce the bias of results (shen et al., 2012; sullivan & artino, 2013; gokdemir & dumludag, 2011). the scientific results will then be presented with a mean score test and non-parametric kruskal-wallis h-test, and mannwhitney u test in the results and discussion section. the techniques for running the data have been practiced and illustrated (kingsford & chan, 2019). 2.2 demographic and geographical profile the sample total is 358 (64% developed countries and 36% developing countries) from 47 countries (figure 1). we analyzed data from the two geographical domains because they represent different urban development stages; the ‘developed countries’ were developed 6 schuman lam et al. / geosfera indonesia 6 (1), 2021, 1-19 with the economy-led development policies. the ‘developing countries’ are ready for progressive development whose future development path is critical for tackling climate change issues. female respondents (56%) are more than male respondents (44%). age 2635 occupies the highest portion (38%) of the sample, followed by age 16-25 (20%), 36-45 (17%), 46-55 (14%), and 56+ (11%).43% are postgraduate, 29% are undergraduate, and 28% below undergraduate. in the professional group, 36% are students, 49% are employed, and 15% are either retired or unemployed. the sample profile reflects a young diversified, and well-educated group of representation, which would serve as the applicable sample to advise the future sustainable urban development requests. figure 1. sample demographic profile female 56% male 44% percentage frequency female male 0% 5% 10% 15% 20% 25% 30% 35% 40% 16-25 (20%) 26-35 (38%) 36-45 (17%) 46-55 (14%) 56+ (11%) age percentage frequency (age) 0% 5% 10% 15% 20% 25% 30% 35% 40% 45% 50% below undergraduate (28%) undergraduate (29%) postgraduate (43%) percentage frequency (education) 0% 10% 20% 30% 40% 50% 60% student (36%) retired/unemployed (15%) percentage frequency (profession) employed (49%) 7 schuman lam et al. / geosfera indonesia 6 (1), 2021, 1-19 3. results and discussion we discuss the results in three parts. several critical issues are highlighted by comparing and analyzing the mean score (ms) ranking results of developing countries, developed countries, and developed mirafiroi community (a post-industrial town in italy was chosen to represent the historical drawback left by industrialization) and significant differences in age, education, profession, and country groups. this section illustrates the perceived well-being evaluation gap between developed countries, developing countries (a proxy of urban and rural well-being representation). it reveals a critical point of demographic groups shaping the loading pattern of geographical representation and restating the relationship of the independent demography to the dependent geography. the finding allows the further exploration of the hybrid urban-ruralism development concept. 3.1 macro: comparing uqol mean rankings by geographical domains the composition of 11 uqol dimensions was extracted from the relevant world quality of life indices (cimi, 2018; gpci, 2018; sci, 2018; scmi, 2017; mqcr, 2018; spi, 2018) guided by the global concept of sustainability development. the 11 identified uqol criteria had been discussed and tested by a professional panel composed of professors / scholars and ph.d. students are the experts in sustainable urban planning, sociology, environmental, architecture, and design engineering from the interuniversity department of regional and urban studies and planning in the politecnico di torino, italy twice. it was then verified by a mean score test at the threshold of µ≥1.5 with a respondent rate over 90% and p-value: 0.000<0.005. the respondents were asked to rank the 11 uqol indicators in a 3point likert scale set. table 1. comparing mean ranking of the 11 uqol indicators dimensions mirafiori2 developed countries3 developing countries4 rm mean sd rank r1 mean sd rank r2 mean sd rank health 98.0 2.91 .353 1 98.7 2.77 .543 1 98.5 2.76 .558 1 environment 96.0 2.65 .578 2 97.4 2.57 .632 2 96.9 2.56 .614 6 mobility 97.0 2.65 .520 2 98.2 2.50 .591 4 96.9 2.62 .578 2 governance 95.0 2.53 .664 4 96.1 2.52 .652 3 95.4 2.57 .587 5 continued 8 schuman lam et al. / geosfera indonesia 6 (1), 2021, 1-19 dimensions mirafiori2 developed countries3 developing countries4 rm mean sd rank r1 mean sd rank r2 mean sd rank human capital 93.1 2.52 .668 5 96.1 2.50 .666 4 94.6 2.59 .572 4 social 97.0 2.47 .692 6 99.1 2.46 .687 6 93.1 2.60 .598 3 economy 95.0 2.04 .807 10 96.5 2.19 .740 8 95.4 2.56 .629 6 technology ict 96.0 2.12 .832 8 95.6 2.13 .722 9 93.1 2.45 .658 8 culture 98.0 2.23 .750 7 96.9 2.21 .710 7 93.1 2.17 .691 10 smart living 93.1 2.05 .821 9 94.7 1.99 .759 10 93.8 2.22 .662 9 lifestyle 93.1 1.89 .782 11 95.2 1.96 .763 11 93.8 2.17 .712 10 note : rm = respondent rate from mirafiori; sample size of rm = 101; r1 = respondent rate from the developed countries; sample size of r1 = 228; r2 = respondent rate from the developing countries; sample size of r2 = 130. total sample size: r1 + r2 = 358; reliability test of the 11 dimensions: cronbach’s alpha (all countries = .845) (developed countries = .848) (developing countries = .825). statistical significance: 0.05; mean score ranking test: µ≥1.5 p-value: 0.000<0.05 for total sample size. 2 = mirafiori is a periphery post-industrial town situated in the capital city of piedmont, turin. turin is italy’s third-largest economic centre after milan and rome and situated in the southern part of the city is a typical marginal motor workers town awaiting revitalization. 3=developed countries: australia, austria, belgium, bulgaria, canada, croatia, czechia, finland, france, germany, greece, ireland, italy, japan, latvia, netherlands, poland, republic of korea, romania, spain, sweden, uk, usa. 4developing countries: argentina, azerbaijan, bangladeshi, benin, brazil, china, colombia, egypt, ethiopia, ghana, india, indonesia, iran, kazakhstan, lebanon, malaysia, mexico, morocco, nigeria, pakistan, philippines, russia, south africa, sri lanka. as expected from table 1, the developed mirafiori community has a similar ranking result as the developed countries, except for mobility and economy, a reflection of well-being gap can exist in the multi-scalar urban system (nation-city-town-village). overall ms scores are 2.48, 2.35, and 2.37 out of 3 for the developing countries, developed countries, and the developed mirafiori community, which can be interpreted as people from the ‘developing countries’ is more driven than from the ‘developed countries’ because the former lives less off than the latter. although the relevantly higher ms score garnered by the developing countries over the other two domains might signal that the macro uqol evaluation is geographically divided into the developed and developing regions, the below combo chart reiterates the well-being gap between the three geographical groups while showing disparities and similarities in the groups. the findings will be examined with a micro illustration. 9 schuman lam et al. / geosfera indonesia 6 (1), 2021, 1-19 figure 2. combo chart of the mean score and ranking lines of the three geographical domains (developing countries, developed countries, and developed mirafiori community) figure 2 is a visual presentation of (table 1) for easy understanding. the top-ranking of health unanimously signifies that urban development should be human-oriented, focusing on healthy social-economic-environmental development as per the need-based survey. we analyzed and discussed the results from three perspectives: (1) developing countries vs. developed countries, (2) developing countries vs. developed mirafiori community, and (3) ms ranking comparison of the three geographical domains. first, a greater uqol ms ranking division exists between the developing and developed countries. the lower the ranking number shows the stronger the well-being criteria demanded by the respondents. the developing countries perceived the environment, governance, and culture(6th, 5th and 10th) as less critical than developed countries (2nd, 3rd and 7th). the developing countries ranked mobility, social and economy criteria (2nd, 3rd and 6th) relatively stronger than the developed countries (4th, 6th and 8th). it indicates that developing countries valued mobility, economic and social development over the developed countries (ali & al nsairat, 2009). worth noting that developing countries have a similar ms of environment (2.56) as the developing countries (2.57), possibly because it has been recognized that environmental quality affects personal health. second, the developing countries and the developed mirafiori community ranked mobility at 2nd place deviated from the developed countries 4th place. it shows that transportation is lacking in the developing and the developed post-industrial town; therefore, the urban development stage might not be the factor for causing the well-being gap when we factor in geographical scale and time would 1 2 6 4 3 5 6 8 10 9 10 1 4 2 4 6 3 8 9 7 10 11 1 2 2 5 6 4 10 8 7 9 11 0 2 4 6 8 10 12 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 r a n k in g m e a n s c o re developing countries developed countries mirafiori-community developing countries developed countries mirafiori-community 10 schuman lam et al. / geosfera indonesia 6 (1), 2021, 1-19 neutralize specific well-being gaps between the two groups. the implication will be investigated in future research because it is not the primary concern of this paper. third, the similar ranking section comprises human capital, technology-ict, smart living, and lifestyle, proving that human-technological-driven as the conventional well-being needs in the digital age. noticeably, the uqol evaluation gap exists between the developing countries and developed countries. the developing countries value socio-economic development relevantly stronger than the developed regions. inside the country group, there are overlapping wellbeing needs by the developing countries and the developed post-industrial town. residents from the once-prosperous motor-town mirafiori want good health and a transport-led habitat where nature, culture, and social activities can flourish with a well-balanced urbanized style. its ms ranking result demonstrates a unique socio-spatial developed post-industrial town. characterized by the local context, constraints, and demands, which originated and built along with the economic-driven agenda, it has since evolved into its color and form to differentiate itself from developed countries. the economy's ranking is surprisingly low (10th place out of 11 indicators) from the post-industrial community; 8th place in the developed countries and 6th place in the developing countries. it demonstrates that gdp as the sole indicator to evaluate people’s well-being needs is not realistic. the economy-led development path needs a facelift to meet the market needs while securing a sustainable future. 3.2 micro: comparing mean score by demographic groups this section illustrates the pattern loading of mean score (ms) disparities by gender, education, profession, and age groups, which provides an in-depth analysis of the macro ms ranking results by geographical domains. we utilized the ms ranking report of sample demography (table 2) to examine the relationship of demographical attributes to the geographical groups while removing the systematic and random errors principally. table 2. mean score reports of sample demography 1 2 3 4 5 6 7 8 9 10 11 gender: female 2.76 2.56 2.53 2.60 2.52 2.51 2.34 2.21 2.13 2.03 2.05 male 2.84 2.61 2.63 2.50 2.60 2.57 2.39 2.32 2.28 2.14 2.01 education: 1 2.87 2.69 2.58 2.62 2.58 2.45 2.06 2.07 2.24 1.98 1.81 2 2.76 2.48 2.49 2.58 2.47 2.51 2.45 2.26 2.22 2.17 2.13 3 2.77 2.58 2.61 2.50 2.59 2.60 2.49 2.37 2.14 2.08 2.11 continued 11 schuman lam et al. / geosfera indonesia 6 (1), 2021, 1-19 1 2 3 4 5 6 7 8 9 10 11 profession: 1 2.86 2.63 2.65 2.55 2.60 2.63 2.50 2.45 2.24 2.18 2.19 2 2.71 2.53 2.50 2.55 2.54 2.48 2.37 2.26 2.21 2.10 2.03 3 2.93 2.64 2.62 2.56 2.51 2.47 1.96 1.78 2.02 1.73 1.67 age: 16-25 2.89 2.64 2.57 2.66 2.62 2.61 2.38 2.30 2.21 2.07 2.16 26-35 2.77 2.55 2.63 2.51 2.52 2.55 2.43 2.41 2.23 2.17 2.12 36-45 2.81 2.63 2.48 2.59 2.59 2.54 2.46 2.26 2.24 2.11 2.09 46-55 2.67 2.58 2.47 2.56 2.58 2.58 2.51 2.29 2.31 2.16 1.98 56+ 2.87 2.55 2.65 2.45 2.45 2.26 1.65 1.52 1.74 1.55 1.45 note : uqol dimensions: 1=health; 2=environment; 3=mobility; 4=governance; 5=human capital; 6=social; 7=economy; 8=technology-ict; 9=culture; 10=smart living; 11=lifestyle education: 1=below undergraduate; 2=undergraduate; 3=postgraduate profession: 1=student; 2=employed; 3=retired / unemployed by referring to the ms results listed in table 1 and table 2, we generated an array of radar diagrams (figure 3) to illustrate the loading pattern of uqol evaluation for discussion. in general, all groups perceived health, environment, mobility, governance, and human capital with similar ms. however, a greater disparity in the economy, technology-ict, culture, smart living, and lifestyle was indicated. the ‘below undergraduate’ perceived the importance of the economy, technology-ict, and lifestyle relatively less significant than the ‘above undergraduate’ in the education group, which needs further investigation to locate the underlying factors. in the professional group, the ‘retired-unemployed’ perceived the value of the social, economy, technology-ict, culture, smart living, and lifestyle relatively less significant than the ‘students’ and the ‘employed’. age 56+ perceived social, economy, technology-ict, culture, smart living, and lifestyle are less critical than the younger groups in the age group.it is mainly due to retired aging respondents being less active in engaging in socio-economic activities and technology-driven lifestyles. 0 1 2 3 health environment mobility governance human capital socialeconomy technology (ict) culture smart living lifestyle education below undergraduate undergraduate postgraduate 0 1 2 3 health environment mobility governance human capital socialeconomy technology… culture smart living lifestyle profession student employed retired/unemployed 12 schuman lam et al. / geosfera indonesia 6 (1), 2021, 1-19 figure 3. mean score disparities of different demographic and geographical groups in figure 3, the micro demographic groups' loading pattern is consistent with the macro country groups, which might state that the independent demographic variables affect the dependent geographical variables. based on this analysis, we revise the original hypothesis ‘urban quality of life (uqol) evaluation gap is caused by demographic and geographical attributes in shaping the urban landscape’ into ‘uqol evaluation gap is caused by demographic and exhibited geographically for shaping the urban landscape. ’by studying demographic uqol evaluation, we can locate the evaluation gap factors for informing future urban development. however, to predict the future urban development beyond the sample representation, we need to conduct the kruskal wallis h-test and mann-whitney u test to identify the statistically significant differences of uqol demands to estimate the urban supply for reaching the equilibrium state of development. 3.3 determining uqol significant differences demographically and geographically table 3 shows basically no perceived value of significant differences in the health, environment, mobility, governance, human capital, and culture criteria meaning that the governments need to distribute resources to accommodate the five well-being requests in their urban policies. kruskal-wallis h-test displays a significant variation in the social, economy, technology-ict, smart living, and lifestyle among the demographic groups. mannwhitney u test highlights significant differences between developing and developed countries in the economy, technology-ict, smart living, and lifestyle. the significant differences criteria inform policymakers to conduct an empirical study to investigate the latent reasons. 0 1 2 3 health environment mobility governance human capital socialeconomy technology (ict) culture smart living lifestyle age age: 16-25 age: 26-35 age: 36-45 age: 46-55 age: 56+ 0.00 0.50 1.00 1.50 2.00 2.50 3.00 health mobility environment human capital social governanceeconomy technology (ict) culture smart living lifestyle country developing countries developed countries 13 schuman lam et al. / geosfera indonesia 6 (1), 2021, 1-19 table 3. kruskal wallis h-test and mann-whitney u test of demographic groups and geographical domains kruskal-wallis h-test mann-whitney u-test dimensions age profession education gender country health 0.754 0.012 a 0.163 0.137 0.872 environment 0.940 0.388 0.201 0.623 0.677 mobility 0.327 0.217 0.511 0.114 0.051 governance 0.472 0.975 0.081 0.174 0.622 human capital 0.653 0.399 0.303 0.241 0.358 social 0.004 a 0.023 a 0.093 0.983 0.080 economy 0.000 a 0.000 a 0.000 a 0.434 0.000 a technology-ict 0.000 a 0.000 a 0.018 a 0.076 0.000 a culture 0.037 a 0.195 0.610 0.148 0.583 smart living 0.002 a 0.005 a 0.147 0.087 0.007 a lifestyle 0.000 a 0.001 a 0.002 a 0.605 0.015 a note : p-valuea < 0.05 shows a statistically significant difference in those dimensions. country: developing countries and developed countries although non-parametric tests were applied to run the datasets, the disproportional number of respondents between groups would inflate the respondents' rate of the bigger group causing a skewed result. the uneven distribution of sample size found among the categories is unavoidable due to conventional sampling. reservation of the findings must be noticed and resolved in the application. therefore, the theory-based scientific study still needs to perform pilot tests locally and consistently in future development. people's minds are often complicated and evolved along the line of demographic and geographical narrative; therefore, different cause-effect of urbanization engendered by people's underlying motives can be realized by studying the concept of planetary urbanization to the uqol evaluation reports. the hypothesis is verified with the three objectives fulfilled: first, the uqol evaluation results indicate the well-being gaps of mobility, economic-socialenvironmental development between the developing and developed countries (rural vs. urban). second, demographic attributes are illustrated as the independent variables to the dependent geographical factors impacting the evaluation gaps. third, the demographic groups display significant differences in the social, economy, technology-ict, smart living, and lifestyle within age, profession, and education categories contributing to most part of the significant differences in the economy, technology-ict, smart living, and lifestyle between developing and developed countries. 14 schuman lam et al. / geosfera indonesia 6 (1), 2021, 1-19 after comparing and discussing the uqol evaluation results and the significant differences, the implication to planetary urbanization theory and contribution of the study is presented for exploring the path to bridge the well-being gap identified between the urban (developed countries) and rural areas (developing countries) for revitalizing the postindustrial town and building the resilient sustainable urban-rural society in developing countries. for a long time, qol is a subjective term without an agreeable definition among people. whereas, uqol evaluation is a specific reflection of the urban condition and can inform future urban development. the study proves that the essence of well-being is health to affirm the human-oriented urban development. the uqol evaluation results by geography and demography indicate that material well-being based on aspects of gdp per person is not related to the quality of life in a country (economist intelligence unit, 2005; european commission, 2009; stiglitz, 2009; pintér et al., 2012). it implies that the current economicdriven urban development planning strategy needs to address local conditions and demands (dna), which planetary urbanization advocates, instead of just considering the overgeneralized city-centered and economy-led urbanization strategies. indeed, urbanization is a socio-economic-spatial process driven by demographic characteristics that directly affect people’s ways of life and urban landscape. it precisely suggests that geography is not the determinator of well-being requests but demography. it is slightly different from the hypothesis stated in section 1: introduction. it means that any living location can fulfill the 11 well-being needs (table 1), people will live there, disregarding urban or rural areas. in the 21st century, technological advancement facilitates transportation and catalyzes inter-connectivity and inter-exchangeability of people, commodities, information, culture, and political ideology. it formulates the new mix of social and cultural patterns, imposing a new challenge for governance. often, cultural gaps and conflicts can disturb any establishment and deteriorate the living environment and quality of life. future urban development needs to address the significant impact triggered by the ict advancement and its means-end relationship of smart living capable of integrating the urban and remote areas in a holistic system. therefore, a drastic urban model shift is expected and should be on the way (raworth, 2018; d’acci, 2019). the concept of planetary urbanization proposed by neil and schmid initiates a new approach to study urbanization apart from the inherited city-centric sprawling outwards extensively to form the capital-led global urban phenomenon. planetary urbanization recognized that urbanism is a process driven by human geography, not a form of one location (arboleda, 2016; goonewardena, 2018; schmid, 2018; wilson et al., 2019). 15 schuman lam et al. / geosfera indonesia 6 (1), 2021, 1-19 urbanization as a collective endeavor with the multifaceted, politicized, and open platform would be modified according to the constitutively hierarchical multi-dimensional urbanization processes; and the specificity of urbanization as one among a multitude of socio-spatial processes which structure the planetary ways of life today (brenner, 2018). thus, understanding the contextual urban problems and neutralizing the rural-urban opposition is necessary for bridging the theoretical and empirical gap (angelo & goh, 2020). the uqol evaluation results of the demographic and geographical groups conclude that geographical constraints are no longer viewed as significant impediments for future development. informed by the significant differences of economy, technology-ict, smart living, and lifestyle. at the same time, the complementary drivers of transit-orienteddevelopment (tod) and ict can foster economic growth for merging the well-being gaps between developed countries and developed countries. furthermore, büchs& koch's (2019) 's elsevier atlas award paper supports degrowth in developed nations is needed to preserve the well-being of future generations as an implication of creating a blend of rural and urban lifestyles. rem koolhass' "countryside the future" exhibition in the guggenheim museum of nyc predicts that the future urban development embraces ruralism. given this, a tod-ict-based urban-ruralism (uxr) concept would contribute to healthy living by releasing the economic-social-environmental pressure from the over urbanized city to the rural region, which could be furnished by the high-speed railway network, sharing economy, and ict advancement. 4. conclusion the three completed objectives conclude that the hypothesis as 'uqol evaluation gap is caused by demographic and exhibited geographically for shaping the urban landscape' by recognizing geography's dependent role on the independent demography. when demographic attributes can define urbanization in the digital period, the tod-ict-based uxr development path for the developing countries and the developed periphery towns will contribute to the future global urbanization process significantly. the study also reminds us that future urban development must focus not only on economic or materialistic requests but also on the health-mobility-social-environmental-cultural-technological strata. the different urban realities from the developing countries to the developed countries and communities appeal to a transitional human-urban-rural development pathway. on the one side, it can guide the developed countries in revitalizing their outdated urban condition to the ‘after a developed period’. on the other side, the tod-ict sustainable strategy can enrich and enhance the urban-rural landscape (human, economy, and society) virtually and physically. 16 schuman lam et al. / geosfera indonesia 6 (1), 2021, 1-19 conflicts of interest the authors declare no conflict of interest. acknowledgments thank you to the politecnico di torino: professor patrizia lombardi, dr. francesca abastante, dr. angioletta voghera, dr. isabella lami, dr. sara torabi, and mr. osman and their ph.d students for pilot testing the survey forms before bulk distribution. also, miss sara cravero has been amazingly helpful and generous in translating the english survey into the italian version. special thanks go to mrs. tecla zaia (president) and mr. sanjay sankar (manager) from the alloggi ami -ngo to distribute and collect the mirafiori survey forms. references ali, h. h., & al nsairat, s. f. (2009).developing a green building assessment tool for developing countries case of jordan. building science, 44(5), 1053– 1064.https://doi.org/10.1016/j.buildenv.2008.07.015. angelo, h., & goh, k. (2020). out in space: difference and abstraction in planetary urbanization. international journal of urban and regional research. https://doi.org/10.1111/1468-2427.12911. arboleda, m. (2016). spaces of extraction, metropolitan explosions: planetary urbanization and the commodity boom in latin america. international journal of urban and regional research, 40(1), 96–112. https://doi.org/10.1111/1468-2427.12290. brenner, n. (2018). debating planetary urbanization: for an engaged pluralism. environment and planning d society and space, 36(3), 570–590. https://doi.org/10.1177/0263775818757510. brenner, n., & schmid, c. (2015).towards a new epistemology of the urban?city (london), 19(2–3), 151–182. https://doi.org/10.1080/13604813.2015.1014712. büchs, m., & koch, m. (2019). challenges for the degrowth transition: the debate about wellbeing. futures, 105(1), 155–165. https://doi.org/10.1016/j.futures.2018.09.002. campbell, a. (1976). subjective measures of well-being. american psychologist, 31(2), 117– 124. https://doi.org/10.1037//0003-066x.31.2.117. cimi, (2018), cities in motion index, 2018. retrieved from https://blog.iese.edu/citieschallenges-and-management/2018/05/23/iese-cities-in-motion-index-2018/. club of rome. (2018). about the club rome. retrieved from https://clubofrome.org/about us/. d’acci, l. (2019). a new type of cities for liveable futures.isobenefit urbanism morphogenesis.journal of environmental management, 246(c), 128–140. https://doi.org/10.1016/j.jenvman.2019.05.129. https://doi.org/10.1016/j.buildenv.2008.07.015 https://doi.org/10.1111/1468-2427.12911 https://doi.org/10.1111/1468-2427.12290 https://doi.org/10.1177/0263775818757510 https://doi.org/10.1080/13604813.2015.1014712 https://doi.org/10.1016/j.futures.2018.09.002 https://doi.org/10.1037/0003-066x.31.2.117 https://blog.iese.edu/cities-challenges-and-management/2018/05/23/iese-cities-in-motion-index-2018/ https://blog.iese.edu/cities-challenges-and-management/2018/05/23/iese-cities-in-motion-index-2018/ https://clubofrome.org/about-us/ https://clubofrome.org/about-us/ https://doi.org/10.1016/j.jenvman.2019.05.129 17 schuman lam et al. / geosfera indonesia 6 (1), 2021, 1-19 dan bar-on, a. caria, m. tazaki, b. murphy, h. herrman, a. noji, … mick power. (1995). the world health organization quality of life assessment (whoqol): position paper from the world health organization. social science & medicine, 41(10), 1403– 1409. https://doi.org/10.1016/0277-9536(95)00112-k. diener, e. d. (1995). a value based index for measuring national quality of life. social indicators research, 36(2), 107–127. https://doi.org/10.1007/bf01079721. dong, h., fujita, t., geng, y., dong, l., ohnishi, s., sun, l., …fujii, m. (2016). a review on eco-city evaluation methods and highlights for integration.ecological indicators, 60(1), 1184–1191. https://doi.org/10.1016/j.ecolind.2015.08.044. economist intelligence unit. (2005). the economist intelligence unit’s quality-of-life index, the world in 2oo5. retrieved from http://www.economist.com/media/pdf/quality_of_life.pdf. european commission. (2009). beyond gdp: measuring progress, true wealth and the well being of nations. retrieved from https://ec.europa.eu/environment/beyond_gdp/index_en.html. gokdemir, o., & dumludag, d. (2011). subjective well-being among ethnic minorities: the dutch case. retrieved from https://mpra.ub.uni-muenchen.de/38691/. goonewardena, k. (2018). planetary urbanization and totality.environment and planning d society and space, 36(3), 456–473.https://doi.org/10.1177/0263775818761890 gpci. (2018) global power city index 2018. retrieved from http://mori-mfoundation.or.jp/english/ius2/gpci2/index.shtml. kingsford o. e., & chan, a. p. c. (2019). barriers affecting effective application of anticorruption measures in infrastructure projects: disparities between developed and developing countries. journal of management in engineering, 35(1), 04018056.https://doi.org/10.1061/(asce)me.1943-5479.0000667. land k.c., michalos a.c., sirgy m.j. (2012) prologue: the development and evolution of research on social indicators and quality of life (qol). in: land k., michalos a., sirgy m. (eds) handbook of social indicators and quality of life research. springer, dordrecht. https://doi.org/10.1007/978-94-007-2421-1_1. marans, r. w. (2015). quality of urban life & environmental sustainability studies: future linkage opportunities. habitat international, 45(p1), 47–52. https://doi.org/10.1016/j.habitatint.2014.06.019. marans r.w., & kweon bs. (2011) the quality of life in metro detroit at the beginning of the millennium. in: marans r., stimson r. (eds) investigating quality of urban life. social indicators research series, vol 45. springer, dordrecht. https://doi.org/10.1007/978-94-007-1742-8_7. marans r.w., & stimson r. (2011) an overview of quality of urban life. in: marans r., stimson r. (eds) investigating quality of urban life. social indicators research series, vol 45. springer, dordrecht. https://doi.org/10.1007/978-94-007-1742-8_1. https://doi.org/10.1016/0277-9536(95)00112-k https://doi.org/10.1007/bf01079721 https://doi.org/10.1016/j.ecolind.2015.08.044 https://ec.europa.eu/environment/beyond_gdp/index_en.html https://mpra.ub.uni-muenchen.de/38691/ https://doi.org/10.1177/0263775818761890 http://mori-m-foundation.or.jp/english/ius2/gpci2/index.shtml http://mori-m-foundation.or.jp/english/ius2/gpci2/index.shtml https://doi.org/10.1061/(asce)me.1943-5479.0000667 https://doi.org/10.1007/978-94-007-2421-1_1 https://doi.org/10.1016/j.habitatint.2014.06.019 https://doi.org/10.1007/978-94-007-1742-8_7 https://doi.org/10.1007/978-94-007-1742-8_1 18 schuman lam et al. / geosfera indonesia 6 (1), 2021, 1-19 mccrea, r., shyy, t. k., & stimson, r. (2006). what is the strength of the link between objective and subjective indicators of urban quality of life? applied research in quality of life, 1(1), 79–96. https://doi.org/10.1007/s11482-006-9002-2. mikkelsen c., & di nucci j. (2015) qualitative methodologies in geography, contributions to the study of quality of life. in: tonon g. (eds) qualitative studies in quality of life. social indicators research series, vol 55. springer, cham. https://doi.org/10.1007/978-3-319-13779-7_5. mqcr. (2018). mercer’s qol city ranking 2018. retrieved from https://www.mercer.com/newsroom/2018-quality-of-living-survey.html. murgaš, f.,& klobučník, m. (2018). quality of life in the city, quality of urban life or wellbeing in the city: conceptualization and case study. ekológia (bratislava), 37(2), 183–200. https://doi.org/10.2478/eko-2018-0016. pintér, l., hardi, p., martinuzzi, a., & hall, j. (2012). bellagio stamp: principles for sustainability assessment and measurement. ecological indicators, 17(1), 20–28. https://doi.org/10.1016/j.ecolind.2011.07.001. potter, j., cantarero, r., & wood, h. (2012).the multi-dimensional nature of predicting quality of life.procedia social and behavioral sciences, 50(c), 781–790. https://doi.org/10.1016/j.sbspro.2012.08.080 raworth, k. (2018). doughnut economics. retrieved from https://www.kateraworth.com/doughnut/. rezvani, m. r., mansourian, h., & sattari, m. h. (2013). evaluating quality of life in urban areas (case study: noorabad city, iran). social indicators research, 112(1), 203– 220. https://doi.org/10.1007/s11205-012-0048-2. rodriguez d. l. (2015) the role of context and culture in quality of life studies. in: tonon g. (eds) qualitative studies in quality of life. social indicators research series, vol 55. springer, cham. https://doi.org/10.1007/978-3-319-13779-7_3. schmid, c. (2018). journeys through planetary urbanization: decentering perspectives on the urban. environment and planning d society and space, 36(3), 591–610. https://doi.org/10.1177/0263775818765476. sci (2018). sustainable cities index, 2018. retrieved from https://www.arcadis.com/en/united-states/our-perspectives/sustainable-cities-index2018/united-states/. scmi (2017). sustainable cities mobility index, 2017. retrieved from https://www.arcadis.com/en/global/our-perspectives/sustainable-cities-mobility-index2017/. shen, l., lu, w., peng, y., & jiang, s. (2012). critical assessment indicators for measuring benefits of rural infrastructure investment in china.journal of infrastructure systems, 17(4), 176–183. https://doi.org/10.1061/(asce)is.1943-555x.0000066. spi (2018). social progress index, 2018. retrieved from https://www.socialprogress.org/. https://doi.org/10.1007/s11482-006-9002-2 https://doi.org/10.1007/978-3-319-13779-7_ https://www.mercer.com/newsroom/2018-quality-of-living-survey.html https://doi.org/10.2478/eko-2018-0016 https://doi.org/10.1016/j.ecolind.2011.07.001 https://doi.org/10.1016/j.sbspro.2012.08.080 https://www.kateraworth.com/doughnut/ https://doi.org/10.1007/s11205-012-0048-2 https://doi.org/10.1177/0263775818765476 https://www.arcadis.com/en/united-states/our-perspectives/sustainable-cities-index-2018/united-states/ https://www.arcadis.com/en/united-states/our-perspectives/sustainable-cities-index-2018/united-states/ https://www.arcadis.com/en/global/our-perspectives/sustainable-cities-mobility-index-2017/ https://www.arcadis.com/en/global/our-perspectives/sustainable-cities-mobility-index-2017/ https://doi.org/10.1061/(asce)is.1943-555x.0000066 https://www.socialprogress.org/ 19 schuman lam et al. / geosfera indonesia 6 (1), 2021, 1-19 stiglitz, j. (2009). towards a better measure of well-being. retrieved from https://www.ft.com/content/95b492a8-a095-11de-b9ef-00144feabdc0. sullivan, g., & artino, a. (2013). analyzing and interpreting data from likert-type scales. journal of graduate medical education, 5(4), 541–542. https://doi.org/10.4300/jgme-5-4-18. unfccc (2016). the paris agreement. retrieved from https://unfccc.int/process-andmeetings/the-paris-agreement/the-paris-agreement. united nations. (2020). sdg moment. retrieved from https://www.un.org/sustainabledevelopment/sdg-moment/. unicef. (2020). trend of urban population. retrieved from https://www.unicef.org/sowc2012/urbanmap/. wced (1987). report of the world commission on environment and development: our common future. retrieved from https://sustainabledevelopment.un.org/content/documents/5987our-commonfuture.pdf. wilson, d., boodram, b. & smith, j. (2019). 2. public housing, heroin addiction, and america’s industrial suburbs: a planetary urbanist perspective. in k. guney, r. keil & m. ucoglu (ed.), massive suburbanization (pp. 56-78). toronto: university of toronto press. https://doi.org/10.3138/9781487531867-005. wilson, d., & jonas, a. e. g. (2018). planetary urbanization: new perspectives on the debate. urban geography, 39 (10), 1576–1580. https://doi.org/10.1080/02723638.20