PERFORMANCE OF SWEET PEPPER UNDER PROTECTIVE STRUCTURE International Journal of Environment ISSN 2091-2854 12 | P a g e INTERNATIONAL JOURNAL OF ENVIRONMENT Volume-12, Issue-1, 2023 ISSN 2091-2854 Received: 19 August 2022 Revised: 12 January 2023 Accepted: 13 January 2023 REGENERATION STATUS AND POPULATION STRUCTURE IN TERAI COMMUNITY FOREST: EVIDENCE FROM KALYANKOT COMMUNITY FOREST, KAPILVASTU DISTRICT, NEPAL Vivek Thapa Chhetri1, Susmita Shrestha1 *, Shweta Parajuli1 and Pabitra Jha1 1Tribhuvan University, Institute of Forestry, Pokhara Campus, Pokhara 33700, Nepal *Corresponding author: susmitashrestha141@gmail.com Abstract The regeneration status of a forest is an essential metrics to assess the regeneration potential and population structure of forests. In emerging nations like Nepal, however, human dependency on forests has had a negative influence on forest diversity and sustainability. This paper analyzes the regeneration status and its link with bio-physical aspects and human disturbances. The data were collected using a systematic random sampling method and sample plots were established using the fishnet tool in ArcGIS. An inventory survey of 96 plots was carried out with nested circular sample plots with a main radius of 1261 cm. The overall regeneration condition of the forest was found to be in good condition according to Community Forestry Inventory Guideline, 2004. The majority of the tree species were determined to have a sound quality and medium (II) grades in this study. In terms of the diameter class distribution, lower diameter classes (21-60 cm) comprised more adults than the upper diameter classes (61-120 cm). This study found no significant variations in the effects of biophysical factors, such as slope and aspect, on species regeneration. The study concludes the inadequate silvicultural management interventions in the forest. This information can be useful to devise systematic plans to promote good-quality regeneration and manage the factors that are likely to affect the overall regeneration. Further research focusing on other biophysical factors as well as social factors and their influence on regeneration including its management techniques is recommended. Keywords: Biophysical variable, Diameter class distribution, Disturbances, Inventory, Seedlings mailto:susmitashrestha141@gmail.com https://orcid.org/0000-0002-6265-0303 International Journal of Environment ISSN 2091-2854 13 | P a g e DOI: https://doi.org/10.3126/ije.v12i1.52439 Copyright ©2023 IJE This work is licensed under a CC BY-NC which permits use, distribution and reproduction in any medium provided the original work is properly cited and is not for commercial purposes Introduction A forest area is comprised of different stages of species composition i.e. seedling, sapling, and tree. The seedling and sapling number in a forest indicates the regeneration status of that forest (Karyati et al., 2013). Enough number of tree species present in the forest indicates successful and satisfactory behavior (Pala et al., 2013) and reflects the productive characteristics of the forest (Chauhan et al., 2008). Natural regeneration is fundamental for forest ecosystem management as well as sustainability (Tesfaye et al., 2010) which is essential for preserving and maintaining global biodiversity (Rahman et al., 2011). Species diversity and forest structure are primarily determined by the regeneration of species over time and space as well as natural and anthropogenic disturbances (Munesh Kumar and Rajwar, 2009). The seedling and sapling population of the species determines the regeneration potential of the forest (Negi and Nautiyal, 2005). Enhancing natural regeneration in forest stands may also be the most economical strategy to create a diverse, productive stand (Pradhan et al., 2019). The study of the regeneration potential and growth status of a species is essential to determine ecosystem stability in the long run (Malik and Bhatt, 2016). Most of the rural populations highly depend on forest resources which leads to forest degradation through the activities like harvesting timber and non-timber forest products, fodder and firewood collection, and domestic grazing (Chapagain et al., 2021). In developing countries like Nepal, human dependency on forest resources challenges biodiversity conservation (Mishra et al., 2004). A healthy forest possesses good regeneration status and predicts good future regenerations (Poudel and Devkota, 2021). However, natural as well as human- induced activities may alter the species diversity, population structure, and composition of the forest ecosystems (Dutta and Devi, 2013). Human disturbances, crown cover, geographical features (slope, aspect, and altitude), soil quality, and climatic condition of the area are the most influential factors to affect the population structure of a forest (Bose et al., 2016; Sapkota et al., 2009a). Successful natural regeneration can be an achievement for long-term forest management and its sustainability (Malik and Bhatt, 2016; Saikia and Khan, 2013). Regeneration along with species richness and diversity is important for the assessment of forests for sustainability, conservation of the species, ecological significance, and policy formation (Kacholi, 2014; R. S. Tripathi and Khan, 2007). Though natural regeneration is a slow https://doi.org/10.3126/ije.v12i1.52439 International Journal of Environment ISSN 2091-2854 14 | P a g e process, it has a significant role in maintaining a stable age structure in forests (Mwavu and Witkowski, 2009), and its improvement is the most cost-effective way in achieving a productive stand with rich species (Liira et al., 2011). Hence, the study of the diverse characteristics of the forest affecting natural regeneration is essential (Mousavi et al., 2011). An understanding of the age distribution of a forest population explains its reproductive potential and predicts its future (Thakur et al., 2021). Community Forestry Inventory Guideline 2004 is a common policy tool for assessing regeneration and yield regulation which is mainly focused on sustainable management of the community forest in Nepal (Sharma, 2017). In forest management, regeneration studies show not only the current state of the forest but also clues about future changes in forest composition. Nepal's forest is a habitat for several species thus improvement of regeneration status is vital to improve the status of degraded forests (Chikanbanjar et al., 2020). As the lowland forests of Nepal are comprised of diverse wild flora and fauna (Paudel and Bhattarai, 2011), sustainable management plan to improve the regeneration is very important. The literature review reveals that there are very limited studies related to the regeneration status in lowland terai forests. Kapilvastu as a district representing lowland terai forest of Nepal and situated in the Terai Arc Landscape (TAL) of Nepal has no such study carried out to date. Thus, a study related to an assessment of population structure reflecting regeneration condition of the forest is very essential that can indicate the entire lowland terai forests of Nepal. Hence, this study was carried out with the objectives to (i) assess the overall population structure (ii) analyze the current regeneration status and (iii) analyze the factors affecting the regeneration. The results of this study are expected to be useful to the wider policy groups for developing essential plans and procedures to improve the regeneration status as well as the overall forest condition in the lowland forests of Nepal. Therefore, research and studies on regeneration provide insights into its current structure and composition contributing further forest management planning and conservation strategies such as seedling and sapling manipulation through minimization of grazing and crown cover regulation. Materials and methods Study area Kalyankot Community Forest is situated in the southern part of the Kapilvastu district of Nepal (Figure 1). The district lies between latitude 27°32′N and longitude 83°3′E at an altitudinal range of 93 to 1491 masl. Geographically, it has plain low lands of Terai and low chure hills with a humid, subtropical climate. Its average annual temperature ranges from 25°C to-19°C with a maximum of 43°C in the summer to a minimum of 4.5°C in the winter. The community forest goes up to 240m from the mean sea level and is surrounded by the Chirai river in the east; Gangate river in the west; Kalyankot (Chure Area) in the north and Indreni community forest in the south. Kalyankot is rich in wild flora and fauna. Shorea robusta (Sal), International Journal of Environment ISSN 2091-2854 15 | P a g e Anogeissus latifolia (Banjhi), Terminalia tomentosa (Sajh), Dalbergia latifolia (Satisal), Tectona grandis (Teak), Eucalyptus camuldensis (Safeda), Madhuca longifolia (Mahuwa) are the dominant tree species in the forest. Figure 1: Map of the study area Data collection Sampling The data were collected using a systematic random sampling method. Sample plots were distributed systematically using the fishnet tool in the Arc toolbox function of ArcGIS 10. 8. If the fishnet was created beyond the boundary, a clipping tool was used to locate the sample plots within the forest boundary and the GPS coordinates of the sample plots were extracted. Each plot was located in the field with the help of a Garmin eTrex 10 device. The sampling intensity of 1% was taken for inventory. The total number of sample plots and plot-to-plot distance was calculated as per the Community Forest Inventory Guidelines, 2004 using the following formulae: 𝑁 = (𝐴 ∗ 𝑆𝐼% ∗ 10000)/𝑃 Where, N= No of Sample Plots A= Area of Forest International Journal of Environment ISSN 2091-2854 16 | P a g e SI= Sampling Intensity P= Plot Size 𝐷 = √𝐴 ∗ 10000/(𝑁 + 1) Where, D= Plot to Plot Distance A= Area of Forest N= No of Sample Plots The circular plots were established for forest inventory. Trees were measured in 500 m2 (r= 12.61m) and poles were measured in 100 m2 (r= 5.64m) plots. The established regeneration (saplings) was measured in the nested concentric circular plot of 25 m2 (r= 2.82 m) and the young regeneration (seedlings) was measured in the nested concentric circular plots of size 10 m2 (r= 1.78 m). Forest inventory The inventory data were collected in the field from 14th to 21st January 2022. The extracted GPS coordinates of the sample plots were inserted in the Garmin GPS and each plot was located in the field. A total of 95 sample plots were surveyed with a 225 m distance between each sample plot. The plots were laid in a concentric and nested way in the field. Measurements (counting the number of individuals of each species) were made in the order of seedlings, saplings, and adults (trees/poles). The young regenerations (seedlings) were considered plants with a height between 30 cm to 100 cm height. The established regenerations (saplings) were considered as plants of height> 100 cm and DBH up to 9.9 cm. Poles and Trees were considered as the plants with DBH 10 cm to 29.9 cm and ≥ 30cm from 1.3 m above the ground level. In addition, canopy cover, aspect, slope, and human disturbances were recorded to find out the relationship between regeneration status and plot variables. The canopy cover (%) for each plot was estimated visually from the center of the plot following Zobel et al. (1987). The disturbance parameters such as grazing, trampling, forest fire, exposed ground, etc. were observed in and around the plot to determine the disturbances following (Haq et al., 2019). Data analysis A regression analysis was performed by SPSS 25 to determine the relationship between regeneration and plot variables. Based on extrapolation per ha basis, the density of adults, seedlings, and saplings were computed International Journal of Environment ISSN 2091-2854 17 | P a g e for the whole forest. Densities (numbers per hectare) of seedlings and saplings of each species were also analyzed to determine the regeneration status of the forest following the community forestry inventory guideline. As per the Community Forestry Inventory Guidelines 2004 (Department of Forest, 2004), the forest condition can be regarded as: (i) 'Good' if the numbers of seedlings and saplings per hectare exceed 5,000 and 2,000 respectively, (ii) 'Medium' if the numbers of seedlings and saplings per hectare lie between 2,000−5,000 and 800−2,000 respectively, and (iii) 'Poor' if the numbers of seedlings and saplings per hectare lie below 2,000 and 800 respectively. The regeneration category of the species was assessed using (Tiwari et al., 2019) as: (a) ‘Good’ if seedling > sapling> adults, (b) ‘Fair’ if seedling > sapling ≤ adults, (c) ‘Poor’ if a species survives only in the sapling stage but not as seedlings, (d) ‘None’ if a species has no seedlings and saplings, and (e) ‘New’ if the species has only seedlings and saplings. Therefore, the regeneration potential of each category was assessed by counting the total number of species in each category of regeneration and dividing by the total number of species representing a value as a percentage of the total species for each forest regeneration category. 𝑅𝑒𝑔𝑒𝑛𝑒𝑟𝑎𝑡𝑖𝑜𝑛 𝑝𝑜𝑡𝑒𝑛𝑡𝑖𝑎𝑙 = 𝑇𝑜𝑡𝑎𝑙 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑠𝑝𝑒𝑐𝑖𝑒𝑠 𝑖𝑛 𝑒𝑎𝑐ℎ 𝑟𝑒𝑔𝑒𝑛𝑒𝑟𝑎𝑡𝑖𝑜𝑛 𝑐𝑎𝑡𝑒𝑔𝑜𝑟𝑦 𝑇𝑜𝑡𝑎𝑙 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑠𝑝𝑒𝑐𝑖𝑒𝑠 ∗ 100 (Pradhan et al., 2019) The tree quality was coded for tree state as: S: sound Tree, DD: Dead and Dying, D: Diseased, TC: Top Cut, L: Leaning and tree grade as: I: Generally straight and clear bole that can potentially yield at least 3 logs of 6 feet length, II: Generally straight bole that can yield at least 2 logs of 6 feet length, and III: Generally branched, crooked with/out hollow inside, and cannot yield any logs of commercial value. Results Adult quality The highest percentage (81%) of the tree population i.e. 314 individuals were found to be in a sound state (without any damage to the tree), whereas 8% of trees were dead and dying, 5% were leaning trees, 4% were top cut and 2% were found diseased (Figure 2). International Journal of Environment ISSN 2091-2854 18 | P a g e Figure 2: Different tree quality present inside the forest Adult Grade Figure 3 shows the wood quality of the tree expressed in Tree Grades i.e. Good (I), Medium (II), and Poor (III). Maximum numbers (44%) of the species were found to be of medium (II) grade followed by 33% of good (I) grade and 23% of poor (III) grade. Figure 3: Wood quality of trees in terms of tree grade DBH classes for Adults A total of 637 tree individuals were recorded with various DBH classes. The overall population structure of tree species concerning DBH classes exhibited the tree individuals from lowest (10-20 cm) to highest (110- 120 cm) DBH class. The highest number (177) of tree individuals were recorded in the DBH class of 20- 30cm and the lowest (5) number of tree individuals were recorded in the DBH class of 10-20cm. The DBH class of 60-70cm and 70-80cm shared an equal (49) frequency of adults, whereas overall tree population structure varied with DBH classes (Figure 4). DD: Dead and Dying 8% Diseased 2% L:Leaning 5% S: Sound Tree 81% TC:Top Cut 4% DD: Dead and Dying Diseased L:Leaning S: Sound Tree TC:Top Cut 33% 44% 23% Good Medium Poor International Journal of Environment ISSN 2091-2854 19 | P a g e Figure 4: Distribution of individual trees in different DBH classes Regeneration status of Kalyankot forest In the entire sample plot of the community forest, the density of seedlings, saplings, and adults were 12756.69, 3063.95, and 305.65 individuals per ha, respectively (Table 1). The overall regeneration condition of the forest was found to be in good condition according to CF Inventory Guideline 2004, as the density of seedlings and saplings exceeded 5000 and 2000, respectively. Shorea robusta, Bauhinia purpurea, Mallotus philippensis, Syzygium cumini, and Bauhinia variegata were major species with a greater number of seedlings/ha. The major species with a greater number of saplings per hectare were Shorea robusta, Bauhinia purpurea, Mallotus philippensis, Terminalia alata, and Bauhinia variegate respectively. Shorea robusta, Anogeissus latifolius, Buchanania latifolia, Mallotus philippensis, and Terminalia alata were 5 major species with a greater density of adult/ha (Table 1). Table 1: Regeneration status of the Kalyankot Community Forest Scientific Name Common Name Family Seedlings/h a Saplings/h a Adults/h a Regeneratio n status category Senegalia catechu (L. F.) P. J.H. Hurter & Mabb. Khayar Fabaceae 0 0 0.25 None Adina cordifolia (Willd. ex Roxb.) Benth. Karam Rubiaceae 12.50 5 0 New Aegle marmelos (L.) Correa Bel Rutaceae 0 0 0.50 None Anogeissus latifolius (Roxb. ex DC.) Bedd. Banjhi Combrataceae 46.13 35 41.83 Fair Bauhinia purpurea L. Tanki, Maluka Leguminosae 1756.25 678.33 0 New 5 177 79 125 73 49 49 35 17 18 10 0 20 40 60 80 100 120 140 160 180 200 F re q u e n c y o f A d u lt s DBH classes (cm) International Journal of Environment ISSN 2091-2854 20 | P a g e Bauhinia variegata L. Koiralo, Kachnar Leguminosae 1059.23 71.67 0 New Buchanania latifolia Roxb. Pyar, Piyari Anacardiaceae 268.75 48.33 37.03 Good Careya herbacea Roxb. Kumbhi Lecythidaceae 43.75 0 2.38 Fair Casearia graveolens Dalzell Badkaule Salicaceae 0 0 1.25 None Cassia fistula L. Rajbriksh a Leguminosae 200.3 59.05 4.52 Good Citrus limon (L.) Burm. f. Nibuwa Rutaceae 0 6.67 0 Poor Colebrookea oppositifolia Sm. Dhursule Lamiaceae 62.5 25 0 New Dalbergia latifolia Roxb.* Satisal Leguminosae 16.67 5 0.5 Good Dillenia pentagyna Roxb. Agai Dilleniaceae 0 0 1.25 None Diospyrus tomentosa Roxb. Bidi pat Ebenaceae 191.37 45.71 1.67 Good Diploknema butyracea (Roxb.) H.J. Lam Chyuree Sapotaceae 0 0 0.25 None Dysoxylum binectariferum (Roxb.) Hook. Dhamina Meliaceae 12.5 5 1 Good Ehretia laevis Roxb. Datrung Ehretiaceae 12.5 5 0 New Eucalyptus camaldulensis Dehn. Masala, Safeda Myrtaceae 25 16.67 0 New Ficus benghalensis Linn. Bar Moraceae 0 0 0.25 None Ficus hispida L. Kharseto Moraceae 66.67 17.50 0 New Ficus neriifolia Sm. Dudhilo Moraceae 45.83 5 9.58 Fair Ficus religiosa L. Pipal Moraceae 0 5 0 Poor Garuga pinnata Roxb. Hook. f. ex Brandis Dabdabe Burseraceae 0 0 10.77 None Lagerstroemia parviflora Roxb. Bot Dhaiyaro Lythraceae 0 3.33 6.55 Poor Leucaena leucocephala Lam.) De Wit Ipil Ipil Leguminosae 20.96 8.33 0 New Litsea monopetala (Roxb.) pers. Kutmero Lauraceae 10.42 4.17 0 New Madhuca longifolia (Koeing) Macbride Mahuwa Sapotaceae 105.06 10 4.25 Good International Journal of Environment ISSN 2091-2854 21 | P a g e Mallotus philippensis (Lam.) Mull.- Arg. Rohini, Sindur Euphorbiaceae 1335.42 536.67 28.24 Good Phyllanthus emblica Linn. Amala Euphorbiaceae 0 4.17 2.29 Poor Schleichera oleosa (Lour.) Oken Kusum Sapindaceae 146.73 16.43 4.25 Good Semecarpus anacardium L.f Bhalayo Anacardiaceae 29.17 34.17 13.90 Poor Shorea robusta Gaertn. Sal Dipterocarpace ae 5246.13 1163.1 90.92 Good Syzygium cumini (L.) Skeels Jamun Myrtaceae 1145.83 18.1 3.46 Good Tectona grandis L.f. Teak, Sagawan Verbenaceae 50 30 3.57 Good Terminalia alata B. Heyne ex Roth Saj Combretaceae 750.89 180.95 18.57 Good Terminalia bellirica Gaertn.) Roxb. Barro Combretaceae 44.64 13.10 13.83 Fair Terminalia chebula Retz. Harro Combretaceae 32.74 4.17 2.79 Good Vitis lanata Roxb. Mahur Vitaceae 0 3.33 0 Poor Woodfordia fruticosa (L.) Kurz Dhayaro Lythraceae 18.75 0 0 New Total 12756.69 3063.95 305.65 Mean 319 77 8 SD 899 221.75 16.74 Regeneration potential Among 40 species observed at the site, 13 species showed good regeneration status, 4 species with fair regeneration, and 6 species showed poor regeneration. Among the remaining species, 10 of them showed new regeneration status while 7 species had no regeneration at all. The regeneration potential for the species under the category good, fair, poor, new, and none was 32%, 10%, 15%, 25%, and 18%, respectively (Figure 5). International Journal of Environment ISSN 2091-2854 22 | P a g e Figure 5: Regeneration status of species inside forest Effect of biophysical variables on the regeneration The majority of the crown cover range was of 0-30% (1744) followed by 30-60% (443) and least of the above 60% (221). Similarly, the highest number of plots were situated in the northern aspect (48) followed by southern (32), western (10) and the least in the eastern aspect (5). Furthermore, the majority of the regeneration were found in the disturbance-free plots from anthropogenic factors (1848) followed by human disturbance plots (560). The regression analysis of the number of regeneration and two biophysical variables i.e. slope (Figure 6) and aspect were found not to be significant (p>0.05). Figure 6: Linear regression between the number of regeneration and slope (in degree) Good 32% Fair 10% Poor 15% New 25% None 18% Good Fair Poor New None y = 0.3711x + 21.338 R² = 0.0121 0 10 20 30 40 50 60 70 80 90 100 0 10 20 30 40 N o . o f re g e n e ra ti o n Slope (Degree) No. of regeneration Linear (No. of regeneration) International Journal of Environment ISSN 2091-2854 23 | P a g e Simple linear regression was used to test if human disturbance predicted the regeneration frequency where, regeneration frequency = 27.58-7.58 (human disturbance). To confirm the level of their relationship, a t-test was performed for regeneration number and human disturbance which indicates that the human disturbance influences the number of regeneration but the effect is not very significant. Table 2Error! Reference source not found. shows that the overall regression was found statistically insignificant (R2= 0.02, p > 0.10). Table 2: Regression between human disturbance and number of regeneration Regression Statistics Multiple R 0.15 R Square 0.02 Adjusted R Square 0.01 Standard Error 21.70 Observations 95 ANOVA df SS MS F Significance F Regression 1 1135.23 1135.23 2.40 0.12 Residual 93 43808.29 471.05 Total 94 44943.53 Coefficients Standard Error t Stat P-value Intercept 27.58 2.65 10.40 2.90018E-17 Human Disturbance -7.58 4.88 -1.55 0.12 Discussion Our study found the mean of the seedlings, saplings and adults to be 319, 77 and 8 indicating the high presence of seedlings in the forest which is suitable from the forest sustainability. The results showed a high number of individuals in the lower dbh classes and a low number of individuals in the upper dbh classes which is similar to the finding of Khamyong et al. (2004). Higher frequency in the lower diameter class may be due to the restriction on felling of small-sized trees and prevailing appropriate environmental conditions, while the extraction of large-sized trees may be the reason for lower frequency in the higher diameter class (Sapkota et al., 2009b; Sarkar and Devi, 2014). High frequency in the lower diameter class represents the sustainable, stable, and good regeneration condition of the forest (Awasthi et al., 2015; Manna and Mishra, 2017) having a high resource utilization capacity (Naidu and Kumar, 2016). The majority of the tree species offered sound quality and the maximum numbers of the species were found to be of medium (II) grade, representing the productive forest which may be supported due to suitable environmental conditions and minimum disturbance factors (Sapkota et al., 2009a). The presence of Shorea robusta, Bauhinia purpurea, Mallotus philippensis, Syzygium cumini, Bauhinia variegate as dominant seedling species suggested a good ability for regeneration, which reflected the International Journal of Environment ISSN 2091-2854 24 | P a g e existing favorable environmental conditions. The study showed a greater number of seedlings per hectare than saplings which aligned with the finding of (Chikanbanjar et al., 2020) that might be due to the presence of appropriate environmental attributes suitable for seedling establishment. Our results showed a higher regeneration potential of Shorea robusta which is consistent with the result of Joshi et al. (2019). Likewise, S. robusta was found to be the dominating tree species in the community forest which is similar to the finding of the inventory (Department of Forest Research and Survey/Forest Resource Assessment, 2014). The community forest's total capacity for regeneration was considered to be satisfactory, indicating high regeneration status; nevertheless, the unsatisfactory rate of 18% regeneration may have an impact on future population trends. The regeneration potential of the forest is found highest in the good condition along with substantive poor and no regeneration potential. Tripathi and Shankar (2014) reported that Sal is always found to be a dominating species in the place of its existence to which our study agrees. There is a high number of seedlings, saplings, and poles of Sal in the forest. Moreover, some species such as Garuga pinnata, Ficus benghalensis, Diploknema butyracea, Dillenia pentagyna, Casearia graveolens, Aegle marmelos, and Senegalia catechu had no seedlings and saplings indicating the least regeneration potential. This could be because of insufficient microclimatic conditions within the forest cover, which in turn will affect tree species' ability to regenerate by seed. The composition of the species with no regeneration will also affect species composition of the forest in the future (Pradhan et al., 2019). Low or inconsistent seed supply, a lack of suitable micro-sites, and/or variables affecting early seedling growth and survival might be the contributing factor to the absence of regeneration (Gärtner et al., 2011). Many studies have assessed the effects of environmental variables in the regeneration of the tree species. The regeneration of the species may vary due to climatic, edaphic, topographic, biological and anthropogenic factors. However, Nepali et al. (2021) explained no significance of the slope and aspect on species richness which commensurate to our finding as the number of regeneration did not vary significantly with the change in slope and aspect. Shah and Shah (2016) established a relationship between slope and the number of regeneration and concluded that rolling slopes had a higher number of regeneration than regular and steep slopes. In contrast, our study did not find any significance of slope on the number of regeneration. In general, anthropogenic factors and natural phenomena affect the regeneration of species (Poudel and Devkota, 2021). Minimal openings in the canopy cover allow higher light transitivity on the forest floor favoring the light- demanding species for the seedling recruitment process (Webb and Sah, 2003). An open canopy is favorable for abundant growth of the seedlings and saplings of light-demanding species like Sal (Gautam and Devoe, 2006). So, it is concluded that thinning activities should be conducted regularly for the proper growth of the seedlings and saplings. Similarly, the effect of human disturbances in the regeneration of the species was found International Journal of Environment ISSN 2091-2854 25 | P a g e statistically insignificant which may be due to sampling bias of the study. Furthermore, this study includes the limitation of smaller sample sizes for the study of effect of biophysical variables and anthropogenic factors which should be addressed by further in-depth studies for the scientific validation. However, the current research findings will help researchers to develop insights into the effects of plot variables in regeneration and assist in developing future management strategies for the community forest. Conclusions This study represents the overall regeneration condition of the forest to be in a good condition. The forest was found to have a higher seedling density, indicating that the population may be sustained if there is no adverse impact of potential increased human interferences in future. The total number of species observed in the forest was 40. The greater species count represents the more number of undesirable species prevalent in the forest changing the vegetation ecology which may be due to insufficient tending operations such as thinning and pruning. Thus, it is recommended to follow tending operations to increase forest productivity. This study helps policymakers about current population structure of lowland terai forests. This study prompts the decision makers to adopt silviculture system based sustainable forest management model to reap forest benefits in a sustainable way without changing vegetation ecology. Further research focusing on other biophysical and social parameters and their effects on regeneration including ways of improving regeneration quality and management techniques should be carried out. Authorship contribution statement V.T. Chhetri, S. Shrestha, and S. Parajuli collected field data, reviewed the literature, and prepared a draft manuscript. P. Jha conducted data analysis, edited and reviewed the manuscript for finalization. Conflicts of interest: The authors declare no conflict of interest. Acknowledgment: We would like to acknowledge the Institute of Forestry, Pokhara Campus for the field inventory arrangement. We would also like to thank Mr. Mahendra Singh Thapa and Mr. Dhruba Bijay GC for guidance during field inventory. We thank Division Forest Office, Kapilvastu, and Kalynakot community forest for accommodation during the field inventory. We thank our colleagues Ms. Swastika Acharya, Mr. Prabin Adhikari, Mr. Rajan Pun Magar, Mr. Manish Poudel, and Mr. Mission Shrestha for their fieldwork assistance. International Journal of Environment ISSN 2091-2854 26 | P a g e References Awasthi, N., Bhandari, S. K., Khanal, Y., 2015. Does scientific forest management promote plant species diversity and regeneration in Sal (Shorea robusta) forest? A case study from Lumbini collaborative forest, Rupandehi, Nepal. 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