untitled ACTA BOT. CROAT. 75 (1), 2016 99 Acta Bot. Croat. 75 (1), 99–108, 2016 CODEN: ABCRA 25 DOI: 10.1515/botcro-2016-0004 ISSN 0365-0588 eISSN 1847-8476 Spring weed communities of rice agrocoenoses in central Nepal Arkadiusz Nowak1,2*, Sylwia Nowak1, Marcin Nobis3 1 Department of Biosystematics, Laboratory of Geobotany & Plant Conservation, Opole University, Oleska St. 22, 45-052 Opole, Poland 2 Department of Biology and Ecology, University of Ostrava, 710 00 Ostrava, Czech Republic 3 Department of Plant Taxonomy, Phytogeography and Herbarium, Institute of Botany, Jagiellonian University, Kopernika St. 27, 31-501 Kraków, Poland Abstract – Rice fi eld weed communities occurring in central Nepal are presented in this study. The research was focussed on the classifi cation of segetal plant communities occurring in paddy fi elds, which had been poorly investigated from a geobotanical standpoint. In all, 108 phytosociological relevés were sampled, using the Braun-Blanquet method. The analyses classifi ed the vegetation into 9 communities, including 7 associa- tions and one subassociation. Four new plant associations and one new subassociation were proposed: Elati- netum triandro-ambiguae, Mazo pumili-Lindernietum ciliatae, Mazo pumili-Lindernietum ciliatae caesu- lietosum axillaris, Rotaletum rotundifoliae and Ammanietum pygmeae. Due to species composition and habitat preferences all phytocoenoses were included into the Oryzetea sativae class and the Ludwigion hys- sopifolio-octovalvis alliance. As in other rice fi eld phytocoenoses, the main discrimination factors for the plots are depth of water, soil trophy and species richness. The altitudinal distribution also has a signifi cant infl uence and separates the Rotaletum rotundifoliae and Elatinetum triandro-ambiguae associations. The study shows that anthropogenic rice fi elds can harbour relatively rich rush and water vegetation. More than 80 species were noted in the vegetation plots. Several of them are considered to be extremely rare and have been recorded on the world Red List. Key words: anthropogenic habitats, Oryzetea sativae, rice fi elds, segetal communities * Corresponding author, e-mail: anowak@uni.opole.pl Introduction Rice production in Nepal plays the most important role in the agricultural economy and in food supply for the soci- ety. A half of the total crop area is devoted to rice cultiva- tion, giving ca 60% of total grain production. However, this fi gure has dropped considerably in the last decade (Gumma et al. 2011). Rice paddy fi elds are located from lowlands (e.g. Tarai) to ca. 3,000 m in the western Himalayas (Jumla valley), which is the highest elevation of rice cultivation in the world (Paudel 2011). More than 70% of the rice-grow- ing area in Nepal is under rainfed conditions. Rice is usual- ly grown only once a year, in the wet season; monsoon rain is the single source of water supply for rice cultivation. More than 60% of the rice production comes from lowland Tarai from the plain valleys of Gandaki, Narayani, Karnali. Rainfed paddies in hills intermountain basins supply main- ly local societies and are less effective. Although Nepal is the world’s second richest country in water resources, more than 18% of the fi elds are irrigated and some southern areas are threatened by draught (CBS 2007). Rice is the most economically important food crop in Nepal. Its production employs two-thirds of the national labour and supplies more than 40% of calories for the people and is crucial for national food security (Gumma et al. 2011). In most parts of Nepal, rice is grown on small family- based subsistence farms with an average size varying from less than 0.1 to 1.0 ha. This fragmentation of holdings pro- motes extensifi cation of rice production and persistence of many weed species in rice segetal agroecosystems. Weeds are considered one of the major problems in rice production in Asia, including Nepal (Papademetriou et al. 2000, Bhatt et al. 2009). Losses due to weeds have been estimated at 12% of the crop yields (Manandhar et al. 2007). Considerable progress in weed control has been achieved with various measures such as ensuring the purity of rice seed, the proper selection of cultivar and seeding rate, the proper planting method, good land preparation and NOWAK A., NOWAK S., NOBIS M. 100 ACTA BOT. CROAT. 75 (1), 2016 water management, hand weeding and chemical weed con- trol, as well as crop rotation (De Datta 1981), used together in a system of integrated weed management. The frequency and abundance of weeds varies with different methods of cultivation. In Nepal, there are several types of rice cultiva- tion, such as upland, dry-seeded, deepwater, transplanted, and wet-seeded or pre-germinated direct-seeded rice. In transplanted or deepwater plantings the weeds are limited by unsuitable conditions for establishment of plants. Direct seeded rice crops are the most weed-infested with yearly yield losses of up to 75% (Manandhar et al. 2007). Rice fi elds are still recognized globally as well as in southern Asia as important refuges for many wetland and water species. Many of them are highlighted by the IUCN as important in terms of biodiversity conservation and red-list- ed. Among others, Lindernia ciliata, Ammannia multifl ora, Ludwigia perennis, Aeschynomene indica, Cyperus miche- lianus, Geissaspis cristata, Limnophila erecta, Marsilea minuta, Hydrocera trifolia and Monochoria vaginalis can be mentioned (IUCN 2013). The increasing food demand will lead inevitably to intensifi cation of rice production and then impoverishment and degradation of rice fi eld phytoco eno- ses. Perhaps this is the last chance to document and classify the vegetation types of rice paddies in south Asia. As to maintain the withdrawing segetal weeds and to stop the impoverishment of agrocoenoses, many conserva- tion actions and research works have been implemented in recent years (e.g. van Elsen et al. 2006). Recent studies were focused mainly on the effect of cultivation methods on the fl oristic composition and richness of weed communi- ties (Kent et al. 2001, Hyvönen and Salonen 2002, Chauhan 2013). Many studies have recorded basic fl oristic and veg- etation data for rice crops, often focussing on their conser- vation value or ecological services (Barrett and Seaman 1980, Camenisch and Cook 1996, Turki and Sheded 2002, Bambaradeniya et al. 2004). Specifi c biological features which are supposed to be responsible for weed decline have received less attention (e.g. Gibson et al. 2006). Phytosoci- ological studies of rice fi eld communities have been carried out for several years mainly in the countries of southern Eu- rope (Bolòs and Masclans 1955, Piccoli and Gerdol 1981, Carretero 1989, Parras and Lorca 1993, Garcia and Benzal 2009), Japan (Miyawaki 1960), the Korean Peninsula (Kol- bek et al. 1996, Kolbek and Jarolímek 2013, Shimoda and Song 2014), Tajikistan (Nowak et al. 2013) and Thailand (Nowak et al. 2015a). To date, no detailed research into the plant communities of these specifi c ecosystems has been conducted in other important regions of rice cultivation, for example, in Indonesia, India, Madagascar or central Asian countries. Thus the main aim of the presented research is to reveal the diversity of weed associations in rice crops in Central Nepal and their syntaxonomical classifi cation with- in the Oryzetea sativae class. Material and methods Study area Nepal is located in southern Asia between 80°03′ and 88°11′E, and 26°21′ and 30°26′N, situated at altitudes be- tween 78 m and 8,848 m (Sagarmatha Peak; Fig. 1). It shares its northern border with China and from the east, south and west it is surrounded by India. The country cov- ers 147,181 km2 with a population of ca 29 million. The country is divided into fi ve main ecological zones: Himala- yas, High Hills, Mid Hills, Siwalik and lowland Terai. The area of the country is drained by three main tributaries of the Ganges: the Kosi, Gandaki and Karnali Rivers. Because of the extreme variations in altitude, topography and physi- cal condition, the agro-climatic conditions, the cultivation methods and types are very diverse in Nepal. On account of the climate there is a considerable variability of rice lan- draces found throughout the country, adapted to specifi c en- vironments. Thus, Nepal is considered a world biodiversity centre for Oryza sativa (Asian rice) diversity (van Dusen et al. 2007). It is estimated that in Nepal about 2000 different landraces of cultivated rice are in use and 4 taxa of wild rice still occurs (O. nivara, O. ruffi pogon, O. offi cinalis and O. granulata; Gupta et al. 1996). The rice paddy fi elds are cat- egorized according to the source of irrigation: seasonal streams (kholapani), rivers of snow-melt-water (gadkule) or waterlogged marshes (sim; Bajracharya et al. 2006). Nepal has tremendously varied climate conditions, from tropical in the south to temperate in the north with alpine and arctic conditions in the highest elevations of the Himala- yan range. The country area is divided into 6 climatic zones: tropical (up to 1,000 m a.s.l.), subtropical (1,000–2,000), temperate (2,000–3,000), subalpine (3,000–4,000), alpine (4,000–5,000) and nival (above 5,000 m a.s.l.). Generally fi ve major seasons are distinguished: spring, summer, mon- soon, autumn and winter. In the north, summers are cool and winters severe, while in the south summers are tropical and winters are mild. In the Tarai, summer temperatures of- ten exceed 37 °C, while winter temperatures range from 7 to 23 °C. In hilly central Nepal and valleys, summers are temperate while winter temperatures can plummet under zero. In Kathmandu the summer temperatures range be- tween 19 and 35 °C and in winter between 2 and 12 °C. The average annual rainfall is 1,600 mm, but it varies by eco- climatic zones, such as 5,500 mm in the windward slopes of Annapurna Himal to below 300 mm in the rain shadows of Mustang. According to biogeographical division of Takhtajan (1986) Nepal belongs to the Sino-Japanese region (Eastern Himalayan province), Irano-Turanian region (Tibetan Prov- Fig. 1. The study area in Central Nepal with main cities and bio- geographical zones. WEED COMMUNITIES OF RICE FIELDS IN NEPAL ACTA BOT. CROAT. 75 (1), 2016 101 ince, Western Himalayan Province), Sudano-Zambezian re- gion (Sindian Province) and Indian region (Bengal and In- dochinese provinces). Central Nepal lies generally in the Bengal province. The fl ora of Nepal counts more than 6,000 fl owering plant species with ca. 250 endemics (Press et al. 2000). This number is still being amended upwards (Ferille and Lach- ard 2013, Nobis et al. 2014a, b). Around 218 vascular plants were reported as weeds of rice paddy fi elds (Moody 1989, Bhatt et al. 2009). Data and analyses During the study, in May 2013, 108 vegetation relevés were collected in rice fi elds in central Nepal (Fig. 1). The sampling sites were located mainly in the valleys of the riv- ers: Trisuli, Kali Gandaki, Rapti, Madi, Marsyangdi, Anahi Khola and Tinau. The size of each vegetation relevé varied from 3 (some plots of water and mud communities) to 25 m2, depending on plant density, homogeneity of vegetation cover and the size of homogenous spatial units. In each relevé, all vascular plant species were recorded according to the cover-abundance scale of Braun-Blanquet (1964). The 7-degree scale was used (r, +, 1, 2, 3, 4, 5). All the relevés were stored in the JUICE program (Tichý 2002). A TWlNSPAN analysis (Hill 1979) and de- trended correspondence analyses (DCA) were performed using the fl oristic data set (presence-absence data, no down- weighting of rare species) to check the manual fl oristic-so- ciological classifi cation and to illuminate the relationships between the groups. For the ordination, CANOCO for Win- dows 4.5 was used (ter Braak and Šmilauer 2002). The rele- vés data showed a clear unimodal response, with total iner- tia of ca. 5. Vegetation classifi cation follows the sorted table ap- proach of Braun-Blanquet (1964). In the analytic tables (Tab. 1, On-line Suppl. Tabs. 1, 2), species constancies are Tab. 1. Associations of the Potametea class in rice fi elds of central Nepal during the study, in May 2013. LS – Lemno-Spirodeletum polyr- rhizae; Nm – Najadetum minoris; CLd – Community of Limnobium dubium; No – number. The cover-abundance scale of Braun-Blan- quet (1964) was used: r = 1 or 5 individuals; + = few individuals (< 20) with cover < 5%; 1 = many individuals (20–100) with cover < 5%; 2 = 5%–25% cover; 3 = 25%–50% cover; 4 = 50%–75% cover; 5 = 75%–100% cover. Successive number of relevé 1 2 3 4 5 6 7 8 9 10 11 12 N o. o f o cc ur re nc e N o. o f o cc ur re nc e N o. o f o cc ur re nc eDay/month 3/5 6/5 6/5 6/5 6/5 7/5 7/5 7/5 7/5 8/5 8/5 8/5 Water depth (cm) 15 15 20 10 13 10 4 5 15 15 15 10 Altitude (m) 568 217 217 217 217 205 190 190 205 377 377 377 Cover of herb layer (%) 70 45 40 70 85 40 55 55 25 65 40 45 Relevé area (m2) 25 25 25 25 25 25 25 25 25 3 3 3 pH 6.8 6.8 – 6.8 7.0 6.5 – 7.2 7.1 – 7.5 – Number of weeds 10 2 3 4 3 3 6 6 2 4 4 3 rel. rel. rel. Association/Community LS LS LS Nm Nm Nm Nm Nm Nm CLd CLd CLd 1–3 4–9 10–12 Cultivated plant Oryza sativa 3 3 4 3 2 3 2 3 3 2 2 2 Ass. Lemno-Spirodeletum polyrrhizae Spirodela polyrrhiza 3 3 2 1 + . . . . . . + 3 2 1 O. Lemnetalia minoris et Cl. Lemnetea minoris Azolla fi liculoides 1 . . . . . . . . . . . 1 – – Ass. Najadetum minoris Najas minor . . . 4 5 3 3 2 2 + + . – 6 2 Comm. Limnobium dubium Limnobium dubium + . . . . . . . . 4 3 3 1 – 3 Accompanying species Echinochloa colona . . . . . + + + 1 . . . – 4 – Cyperus difformis + . . . . . + . . + + 1 1 2 Alternanthera sessilis 1 . . . . . + 1 . . . . 1 2 – Cyperus iria 1 . . . . . . . . + + . 1 – 2 Centella asiatica . . . . . . 2 3 . . . . – 2 – Polygonum barbatum . 1 2 . . . . . . . . . 2 – – Elatine triandra . . . . . 1 + . . . . – 2 – Echinochloa crus-galli . . . . . + . + . . . . – 2 – Sporadic species: Commelina diffusa 1(+); Cynodon dactylon 5(+); Dopatrium junceum 10(+); Elatine ambigua 4(+); Fimbristylis mili- acea 4(+); Lindernia anagallis 1(+); Lindernia ciliata 3(+); Rotala rotundifolia 1(1); Veronica beccabunga 1(2). Locality of relevé: 1 – (274548,3; 850244,4); 2, 3, 4, 5 – (273454,5; 842941,6); 6, 7, 9 – (273459,1; 842937,5); 8 – (273522,3; 842954,5); 10, 11, 12 – (274804,5; 845203,8). NOWAK A., NOWAK S., NOBIS M. 102 ACTA BOT. CROAT. 75 (1), 2016 given in constancy classes (Dierschke 1994). In the case of fewer than 8 relevés, the absolute number of species occur- rences was specifi ed. Some newly presented communities are described as associations according to the International code of phytosociological nomenclature (Weber et al. 2000). The presented communities are arranged into a syntaxo- nomic overview at the end of the description. For documentation of basic habitat conditions govern- ing the occurrence of the community, alkalinity was deter- mined with an ELMETRON CP-105 pH meter. Plant names were adopted mainly after the International Plant Names Index (2012). The herbarium collection is hosted in OPUN (Opole University, Opole). Results General fl oristic features The number of taxa recorded in the relevés totals 82, with 68 taxa exceeding 1% constancy and 47 taxa 5%. Those with the highest constancy are: Alternanthera sessil- is (83 concurrencies), Cyperus difformis (65), Mazus pumi- lus (61), Echinochloa colona (52), Centella asiatica (45), Cynodon dactylon (44), Fimbristyllis miliacea (44), Linder- nia ciliata (39), Cyperus iria (34), Lindernia procumbens (31), Veronica anagallis-aquatica (28), Elatine triandra (26), Bacopa procumbens (25) and Marsilea minuta (21). The sampled plots of vegetation are almost exclusively composed of species originating from the Oryzetea sativae class (Miyawaki 1960). Only a few species, like Cynodon dactylon, Veronica anagallis-aquatica, V. beccabunga, Jun- cus prismatocarpus, Ranunculus sceleratus, Vicia hirsuta, Chenopodium album, Paspalum distichum and Portulaca oleracea, often occur outside the hygrophilous vegetation of paddy fi elds. They occupy mostly drier segetal and ru- deral habitats or are typical for rushes. Cynodon dactylon has a wider ecological amplitude and was spotted in mud, meadow and rush communities. There is also a distinct group of obligatory water species such as Spirodela polyr- rhiza, Limnobium dubium, Azolla fi liculoides, Nymphaea nouchalii and Vallisneria spiralis. But the majority of the taxa found are related to muddy biotopes and have an am- phibious character. Numerical ordination The detrended correspondence ordination run for the entire data set distinctively separates the water plant com- munities which are set to the left part of the diagram. Those are the Limnobium dubium community, Najadetum minoris and Lemno-Spirodeletum polyrrhizae (Fig. 2). The gradi- ents of water decrease and plots related to communities oc- curring on mud are located on the right part of the diagram. The associations of Elatinetum triandro-ambiguae and Ro- taletum rotundifoliae are positioned in the bottom part of the graph. They prefer rainfed paddy terraces with clayey, brown muds as a soil substrate and intermediate period of water inundation. Phytocoenoses concentrated in the cen- tral and right parts of the graph are similar in terms of habi- tat preferences. They occupy muddy soils with higher tro- phy and are generally composed of higher number of species despite the lower total cover of herb layer (Figs. 2, 3). Only the Marsileetum minutae association is rather spe- cies poor and occurs in rice stands during the early pheno- logical phase. The Mazo pumili-Lindernietum ciliatae as- sociation is considerably dispersed, showing the highest variability in fl oristic structure. Several plots with a greater amount of sand fraction in the soil have been classifi ed as subassociation with frequent occurrence of Caesulia axil- laris as diagnostic species. The upper section of the fi gure is occupied by plots related to Ammanietum pygmeae. This phytocoenosis is relatively species rich, however with low abundance of weeds. It develops on fertile muddy sub- strates in irrigated fi elds located in the warmest areas in the Kali Gandaki River valley. The association has a loose, open structure and was found on sites with low rice stands density. All of the defi ned plant associations are relatively distinct. Only some small overlaps occur, because of habitat similarities and there are some widely distributed, non-spe- cifi c species in common (Alternanthera sessilis, Cyperus difformis, Cynodon dactylon, Echinochloa colona). This lack of powerful discrimination between some associations in the DCA could be also due to the relatively low number of species per relevé in rice fi eld phytocoenoses and to a low degree of fi delity for some rush or aquatic species. It is widely known, that although species of hygrophilous habi- tats display certain habitat preferences, different associa- tions can thrive in the same pond (Riis et al. 2000, Hatton- Ellis and Grieve 2003, Gacia et al. 2009). Fig. 2. Detrended correspondence analysis ordination for all sam- ples (N = 108). WEED COMMUNITIES OF RICE FIELDS IN NEPAL ACTA BOT. CROAT. 75 (1), 2016 103 Syntaxa of rice fi elds in central Nepal 1. Marsileetum minutae Nowak A., Nowak S., Nobis M. 2015 (On-line Suppl. Tab. 2, rel. 43–48) Diagnostic species: Marsilea minuta This phytocoenosis has been found at a height of 200– 370 m a.s.l. in the valleys of the Rivers Seti and Anahi Kho- la. Most of the plots of this association were found on wet mud or in shallow water inundation up to 10 cm (mean: ap- proximately 5 cm). The community develops on rather fer- tile soils with close to neutral pH (7.3). The total herb layer cover is characterised by intermediate values in relation to other rice fi eld phytocoenoses. The mean cover in research plots was about 40%, ranging from ca. 5% to 50% (Fig. 3). In central Nepal, Marsileetum minutae is a community composed of 3–7 species with a clear predominance of the diagnostic species, Marsilea minuta. Within the study sites the dwarf water clover clearly dominates, reaching up to 50% cover on plot surfaces. The most frequent accompany- ing taxa of the association are Alternanthera sessilis, Cype- rus difformis and Centella asiatica. Fig. 3. Species richness, Shannon diversity index, cover of herb layer, water depth and altitudinal distribution of rice fi eld communities in central Nepal. Abbreviations: LS – Lemno-Spirodeletum polyrrhizae, Nm – Najadetum minoris, Cld – community of Limnobium dubium, Rr – Rotaletum rotundifoliae, Eta – Elatinetum triandro-ambiguae, ML – Mazo pumili-Lindernietum ciliatae, Ap – Ammanietum pygme- ae, Mm – Marsileetum minutae, Ca – Mazo pumili-Lindernietum ciliatae caesulietosum axillaris. Whiskers present minimum and maxi- mum observations within fences, block indicates fi rst and third quartile, circles the minimum and maximum value. Outliers are shown as asterisks. NOWAK A., NOWAK S., NOBIS M. 104 ACTA BOT. CROAT. 75 (1), 2016 2. Najadetum minoris Ubrizsy 1961 (Tab. 1, rel. 4–9) Diagnostic species: Najas minor This phytocoenosis occurs rarely in shallow waters of irrigated rice paddies in the surrounding of Sauraha village in Rapti River valley. It has been noted at the lowest loca- tions, around 200 m a.s.l. Najadetum minoris grows in rela- tively small patches in whole paddy surface in dens as well as in loose rice stands. It prefers warm, shallow and neutral waters with depths of 5 to 15 cm (mean approx. 10 cm; Fig. 3, Tab. 1). The herb layer of this association is relatively abundant. The mean total cover of vascular plants is ap- proximately 50%, ranging from 15% to almost 90%. How- ever, this is not refl ected in species richness, which is one of the lowest, with a mean value of approx. 4 species per plot. Apart from the diagnostic species, the greatest cover and constancy in this phytocoenosis is shared by Echinochloa colona, Centella asiatica and Alternanthera sessilis (Tab. 1). 3. Elatinetum triandro-ambiguae ass. nova hoc loco (On- line Suppl. Tab. 2, rel. 1–17) Nomenclatural type: On-line Suppl. Tab. 2, relevé 1 Diagnostic species: Elatine ambigua, E. triandra The Elatinetum triandro-ambiguae was defi ned by the abundant occurrence of the diagnostic species in rainfed paddies of the Kali Gandaki, Marsyangdi, Trisuli and Anahi Khola Rivers near Putalibazar, Aanbu Khaireni, Kurintar, Bharatpur and Siurenitar cities. It was found generally in dried-up or shallowly inundated rice fi elds with very scarce abundance of cultivated plants. The association was noted on sites with mean water depth value close to 0 cm (Fig. 3) on loamy and clayey soils with pH ca. 7.0. The herb layer develops to moderate values of approximately 15–85% (mean: ca. 45%; Fig. 3; On-line Suppl. Tab. 2). Elatinetum triandro-ambiguae is a community of intermediate species richness, with 4 to 14 taxa per plot (mean approx. 10). Cen- tella asiatica, Echinochloa colona and Dopatrium junceum are the most frequent taxa of this association. 4. Lemno-Spirodeletum polyrrhizae Koch 1954 (Tab. 1, rel. 1–3) Diagnostic species: Spirodela polyrrhiza This phytocoenosis occurs with very rare frequency in central Nepal. It was found only in two sites in the Rapti River valley (near Sauraha village) and in the Trisuli River valley (near Goganpani village). It was noted at heights of about 217 and 568 m a.s.l. The association of Lemno-Spiro- deletum polyrrhizae develops in the study area in relatively deep waters (15–20 cm; Fig. 3) on muddy ground with pH approx. 6.8. It was observed in moderately developed rice stands in early growth phases. The community is character- ised by a moderate average herb layer cover. Values of 25 to 65% were noted (mean ca. 40%; Fig. 3). As in other parts of the association range, the plots are characterised by rather low species richness, however in one plot 10 taxa were not- ed. Apart from the diagnostic plant only Polygonum barba- tum share was noticeable in research plots. 5. Mazo pumili-Lindernietum ciliatae ass. nova hoc loco (On-line Suppl. Tab. 1, rel. 1–39) Nomenclatural type: On-line Suppl. Tab. 1, relevé 17 Diagnostic species: Lindernia ciliata, Mazus pumilus This phytocoenosis appears to be the most frequent in Central Nepal, especially at lower elevations. As well as in the irrigated fi elds in Kali Gandaki and Rapti River valleys near Sauraha and Bharatpur, it was noted near Jarebagarm Goganpani and Kurintar in Trisuli River valley. This asso- ciation seems to be most typical for the mid-hills and low- lands of southern Asia within the Oryzetea sativae vegeta- tion. The community has been noted mainly at elevations of approx. 200 m with the exception of the Trisuli valley where the plots have altitudes of approx. 400–600 m a.s.l. (On-line Suppl. Tab. 1). Vegetation patches dominated by Lindernia ciliata and Mazus pumilus develop on paddies with low water depths (0–10, mean 1 cm), on clayey or loamy muds with neutral reaction (pH approx. 7.0). Values of total herb layer cover are moderate in comparison to oth- er rice fi eld associations. The noted mean value was about 35%, ranging from approx. 15% to 65%. The Mazo pumili- Lindernietum ciliatae is an association with a relatively high average number of species per plot. Approximately 11 plants were noted in each sample (range: 7 to 16). Besides the diagnostic taxa, the predominant species are Cyperus difformis, Alternanthera sessilis, Echinochloa colona, Fim- bristylis miliacea and Lindernia procumbens. The subassociation Mazo pumili-Lindernietum ciliatae typicum is widespread in central Nepal on clayey and loamy soils, inundated for a relatively long period by shallow wa- ter. The diagnostic species of the subassociation typicum and the nomenclatural type are identical with those of the association. 6. Mazo pumili-Lindernietum ciliatae caesulietosum axil- laris subass. nova hoc loco (On-line Suppl. Tab. 1, rel. 40– 48) Nomenclatural type: On-line Suppl. Tab. 1, relevé 40 Diagnostic species: Caesulia axillaris This subassociation appears to be typical for hilly landscapes with rainfed paddies on soils with a relatively high amount of the sand fraction. The plots of this syntax- on was found in the Trisuli River valley at a few sites near Chuwabote Gaun. It was also sporadically noted in low- lands near Sauraha in the Rapti River valley. The phyto- coenosis of Mazo pumili-Lindernietum ciliatae with the contribution of Caesulia axillaris develops on wet, sandy muds without inundation (Fig. 3). The soil pH reaction measured near Chuwabote Gaun was 7.8. The herbaceous layer was not abundant in plots, and had a mean value of approximately 30% (range: approx. 20%–40%). However, the phytocoenoses were relatively rich in species, having more than 10 species per plot on average. The most fre- quent and abundant taxa apart from the diagnostic ones were: Alternanthera sessilis, Bacopa procumbens, Cyper- us iria, Scirpus juncoides, Fimbristylis miliacea and Echi- nochloa colona. WEED COMMUNITIES OF RICE FIELDS IN NEPAL ACTA BOT. CROAT. 75 (1), 2016 105 7. Rotaletum rotundifoliae ass. nova hoc loco (On-line Suppl. Tab. 2, rel. 18–33) Nomenclatural type: On-line Suppl. Tab. 2, relevé 20 Diagnostic species: Rotala rotundifolia The association occurs sporadically in Central Nepal in the Trisuli and Seti River valleys (cities of Goganpani, Aambu Khaireni, Dhaptar and Damauli). It prefers higher elevations in mid-hill landscapes at altitudes of 360 to 400 m a.s.l. (Fig. 3). Rotaletum rotundifoliae is associated with loamy and clayey muds of pH approx. 6.5. The research plots were sampled in sites of moderate water depth, how- ever some patches were quite deeply inundated. The mean water depth was approx. 4 cm. Between 7 and 18 species were recorded in a single plot (mean approx. 9). The phyto- coenoses are characterised by a moderate herb layer cover. The maximum cover of weed species in the phytocoenoses was about 75%. The mean cover of whole herbaceous layer was ca. 45%. (Fig. 3). The diagnostic Rotala rotundifolia has relatively high cover in all plots, reaching up to 50% maximum value (mean approx. 25%). Among the most abundant and constant species in the phytocoenosis are Al- ternanthera sessilis, Centella asiatica, Cynodon dactylon, Dopatrium junceum and Monochoria vaginalis. Several rush species like Veronica anagallis-aquatica were also noted in the sampled plots. 8. Ammanietum pygmeae ass. nova hoc loco (On-line Sup- pl. Tab. 2, rel. 34–42) Nomenclatural type: On-line Suppl. Tab. 2, relevé 34 Diagnostic species: Ammania pygmea, Callitriche palustris var. oryzetorum, Dichostylis micheliana The association is a very distinct from other segetal weed communities noted in rice fi elds in Central Nepal. It is associated mainly with relatively open, loose rice stands with small amounts of water, often completely dried up. In the research area the Ammanietum pygmeae was noted in the lowest elevation in Chitwan National Park vicinity in the Rapti River valley (near Sauraha, Ratnanagar and Bharatpur) within the altitudinal range between 184 to 217 m a.s.l. (Fig. 3). The association develops on wet and fer- tile muds in irrigated fi elds in the bottoms of the river val- leys. The soil is neutral or slightly acidic (pH 6.4–7.1). Plots of the association are relatively rich in species, hav- ing from 10–14 taxa (mean approx. 12). The total cover of weed species in the phytocoenoses rarely exceeds 60%, and in most cases it varies about 35% (Fig. 3). Typical of the observed plots was the insignifi cant cover of the diag- nostic species – Ammania pygmaea, which reaches the av- erage value of approx. 3%. However this species as well as Dichostylis micheliana and Callitriche palustris var. oryzetorum contribute only to this phytocoenosis. Among other species, the highest constancy is found in Echino- chloa colona, Fimbristylis miliacea, Lindernia procum- bens, Mazus pumilus and Vernonia cinerea. The last spe- cies is typical rather for ruderal wet wastelands and its occurrence is related to high openness of the Ammanietum pygmeae. 9. Limnobium dubium community (Tab. 1, rel. 10–12) Diagnostic species: Limnobium dubium (Syn. Hydrocharis dubia) This community was noted in only 3 spots in the Trisulu river valley in the very early stages of rice cultivation. The community was noted at an elevation of ca. 380 m a.s.l. (Fig. 3). The species is typical of various kinds of natural as well as artifi cial bodies of water in subtropical and tropical southern and south-eastern Asia as well as northern Austra- lia (eFlora 2014). Due to the scarcity of phytosociological data as well as the extreme simplicity of the community, it cannot be defi ned as an association at present state of re- search. Synopsis of syntaxa Based on this study, we propose the following classifi - cation for the weed communities of rice fi elds in central Nepal: Class: Lemnetea minoris R. Tx. 1955 O: Lemnetalia minoris R. Tx. 1955 All: Lemnion gibbae R. Tx. et A. Schwabe 1974 in R. Tx. 1974 1. Lemno-Spirodeletum polyrrhizae Koch 1954 Class: Potametea Klika in Klika et Novák 1941 O: Potametalia Koch 1926 All: Potamion Miljan 1933 2. Najadetum minoris Ubrizsy 1961 3. Limnobium dubium community Class: Oryzetea sativae Miyawaki 1960 O: Cypero-Echinochloetalia oryzoidis O. Bolòs & Masclans 1955 All: Ludwigion hyssopifolio-octovalvis Nowak A., Nowak S., Nobis M. 2015 4. Elatinetum triandro-ambiguae ass. nova 5. Mazo pumili-Lindernietum ciliatae ass. nova 6. Mazo pumili-Lindernietum ciliatae caesulietosum axillaris subass. nova 7. Rotaletum rotundifoliae ass. nova 8. Ammanietum pygmeae ass. nova 9. Marsileetum minutae Nowak A., Nowak S., Nobis M. 2015 Discussion The rather variable landscape of central Nepal, the alti- tudinal amplitude, climate seasonality, habitat differentia- tion, various kinds of water supply of the fi elds, with differ- ent methods of rice cultivation, promote the development of several segetal phytocoenoses within paddy fi elds. Our research reveals a relatively rich weed fl ora if compared to other studies on Nepal crop agroceonoses which report ca. 40–60 species (e.g. Manandhar et al. 2007, Bhatt et al. 2009, Sapkota et al. 2010). The richness of rice agro- coenoses is surely related to the extremely rich species pool NOWAK A., NOWAK S., NOBIS M. 106 ACTA BOT. CROAT. 75 (1), 2016 in the whole country. Nepal is known from its extremely rich vascular fl ora and was indicated as one of the world’s biodiversity hotspots (Mittermeier et al. 2006). Despite the ongoing processes of mechanisation and modernisation of agriculture in Nepal including the System of Rice Intensifi - cation (Dobermann 2004, Uprety 2010), the rice fi eld plots are still abundant and diverse in weed species. This allows phytosociological studies and brings credible data relating species composition and habitat preferences of weed spe- cies communities. Then, the well developed associations could be easily defi ned and classifi ed in the hierarchical system of the Oryztea sativae class (Miyawaki 1960, Now- ak et al. 2013). However, the fi nal appearance of the syn- taxonomical system of the class for southern and eastern Asia still needs thorough and detailed studies in many re- gions, e.g. in Burma, India, Sri Lanka, Vietnam and other countries. Our preliminary investigations in Cambodia, southern Thailand, Malaysia, Indonesia and Philippines show, that the beta diversity of rice fi eld phytocoenoses is considerably high and reveals many syntaxa still to be de- scribed. This of course could cause changes in the diagnos- tic value of particular species and need of revision of the system. But even without comprehensive data for the whole SW Asia region, after our studies we can be sure of the ex- treme richness of rice fi eld vegetation and fl ora in southern and south-eastern Asia in comparison to phytocoenoses known from southern Europe, Middle Asia and Japan (e.g. Bolòs and Masclans 1955, Miyawaki 1960, Carretero 1989, Nowak et al. 2013). Obviously the rice phytocoenoses differ substantially in species composition to agrocoenoses known from Mediter- ranean and temperate climates. Despite several common taxa diagnostic generally on the order level (Cypero-Echin- ochloetalia oryzoidis O. Bolòs & Masclans 1955) like Cyn- odon dactylon, Cyperus difformis or Echinochloa crus-gal- li, almost all other species are different. So, even if we compare relatively areas close to Nepal such as Tajikistan, the differences in fl oristic composition achieve the level of ca. 80%. But there is also considerable distinctiveness be- tween Nepal rice weed fl ora and tropical rice plant commu- nities of southern Thailand. The latter is characterised by frequent occurrence of Leptochloa chinensis, Ipomea aquatica, Echinochloa crus-galii, Sphenoclea zeylanica, Ludwigia hyssopifolia, Eclipta prostrata, Ludwigia oc- tovalvia, Leersia hexandra, Hymenachne acutigluma and Aeschynomene indica. The only common and also frequent species for both areas are Alternanthera sessilis, Fimbristy- lis miliacea, Cyperus difformis and Echinochloa colona. This could suggest that the Nepal rice association should be placed in separate alliance. To decide whether it is reliable to distinguish new alliance closely related to the provision- ally proposed Ludwigion hyssopifolio-octovalvis further data collection is needed from the whole area of Nepal as well as from India, Sri Lanka, Bangladesh and Burma. At present the only constant and abundant species for the whole data set gathered in central Nepal are Mazus pumilus, Lindernia ciliata and Alternanthera sessilis. But these spe- cies have a wide geographical range and also occur in east- ern and south-eastern Asia, so they demonstrate considera- ble weaknesses as diagnostic taxa. That is why we decide to classify the described communities within the provisional alliance of Ludwigion hyssopifolio-octovalvis proposed for southern Thailand (Nowak et al. 2015a) even though Lud- wigia octovalvis and L. hyssopifolia were very scarce in our data set from Nepal. The detrended correspondence analysis ordination run for the entire data set clearly segregates the main syntaxa (Fig. 2). The comparison of habitat requirements and fl oris- tic structures of the phytocoenoses found shows that the main dissimilarities in species compositions are due to wa- ter depth and trophy of the soil substrate. The left part of the diagram is occupied exclusively by plots of typically aquat- ic, permanently inundated habitats related to the Limno- bium dubium community, Najadetum minoris and Lemno- Spirodeletum polyrrhizae. In the bottom part of the diagram the samples of relatively species poor phytocoenoses of moderately fertile substrates are grouped. Both associa- tions, Elatinetum triandro-ambiguae and Rotaletum rotun- difoliae, were found on brown, loamy and clayey soils of slightly acidic reaction. Conversely, species rich phyto- coenoses could be found in the upper part of the diagram. They prefer periodically inundated but sometimes dried-up fi elds located generally in lowland river valleys on muddy, fertile, close-to-neutral soils. Despite the signifi cant species diversity, these communities, especially Ammanietum pyg- meae do not achieve high cover of weeds. This shows the close relation of that type of vegetation to early succession- al stages of associations belonging to the Isoëto-Nanojun- cetea class. Altitude is a crucial environmental variable infl uencing the species composition of weed phytocoenoses, particular- ly in mountainous areas (e.g. Lososová et al. 2004, Cim- alová and Lososová 2009, Nowak et al. 2015b). Although we did not explore in detail the variation of weed vegeta- tion explained by altitude, looking at the species composi- tion it is obvious that elevation above sea level, despite the homogenising effects of agricultural practices, is responsi- ble for a considerable degree of the diversity of central Ne- pal rice phytocoenoses. The higher elevations and hilly col- line and montane belts are preferred by the associations of Rotaletum rotundifoliae and Elatinetum triandro-ambig- uae. The apparent differences in climatic conditions be- tween the lowland tropics and montane zone is clearly re- fl ected in species compositions. Several species have found here their ecological optimum, among them Cyperus pulcherrimus, Lindernia antipoda, L. anagallis or Dopatri- um junceum. As regards the geography of the described plant com- munities, at the present state of research it is hardly possible to show their range limits. There is still a lack of credible data regarding the phytosociology and co-ocurrence of rice weeds in southern Asia. Undoubtedly, the Lemno-Spirodele- tum polyrrhizae Koch 1954 and Najadetum minoris Ubrizsy 1961 are plant communities distributed worldwide. Other phytocoenoses noted in the research area have more unique character and presumably occupy subtropical and tropical zones of south-eastern Asia. To state precisely to what ex- tent and how frequently, further detailed studies are needed. WEED COMMUNITIES OF RICE FIELDS IN NEPAL ACTA BOT. CROAT. 75 (1), 2016 107 There is still a need to analyze the weed occurrence in rice paddy fi eld not only in context of agriculture (problems with yield losses, weeding effectiveness), but also consider- ing the conservation issues. Looking inside the fl oristic structure of rice phytocoenoses it is obvious that many weeds originated from former marshlands. After transfor- mation of wetland habitats of river valleys into rice paddies, many species were able to adapt to new environments and regular human impact. The sump pond of rice fi elds, canals, drainage ditches could harbour many species known for- merly exclusively from natural marshlands. Many of them are regarded as rare and listed on the world red list of vas- cular plants (IUCN 2013). Generally they are assessed as of least concern, but with the demand for permanent monitor- ing and evaluation against IUCN criteria. In Central Nepal we noted Lindernia ciliata, L. antipoda, L. anagallis, Am- mannia baccifera, A. multifl ora, Dopatrium junceum, Lud- wigia perennis, L. hyssopifolia, L. octovalvis, Caesulia ax- illiaris, Elatine ambigua, Eleocharis retrofl exa, Lippia no difl ora, Cyperus difformis, C. diffusus, C. iria, C. miche- lianus, C. rotundus, Marsilea minuta, Monochoria vagina- lis, Najas minor, Nymphaea nouchali in vegetation plots of rice fi elds. 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E., Moravec, J., Theurillat, J.-P., 2000: International code of phytosociological nomenclature. Journal of Vegeta- tion Science 11, 739–768. WEED COMMUNITIES OF RICE FIELDS IN NEPAL ACTA BOT. CROAT. 75 (1), 2016 O n- lin e Su pp l. Ta b. 1 . C om m un iti es o f t he O ry ze te a sa tiv ae c la ss (p ar t I ) d ur in g th e st ud y, in M ay 2 01 3. M L – M az o pu m ili -L in de rn ie tu m c ili at ae , M L C -M az o pu m ili -L in de rn ie tu m c ili at ae c ae su lie to su m a xi lla ri s. T he c ov er - ab un da nc e sc al e of B ra un -B la nq ue t ( 19 64 ) w as u se d : r = 1 o r 5 in di vi du al s; + = fe w in di vi du al s (< 2 0) w ith c ov er < 5 % ; 1 = m an y in di vi du al s (2 0– 1 00 ) w ith c ov er < 5 % ; 2 = 5 % –2 5% c ov er ; 3 = 2 5% –5 0% c ov er ; 4 = 5 0% – 75 % c ov er ; 5 = 7 5% –1 00 % c ov er . Su cc es si ve n um be r o f r el ev é 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 Constancy Constancy D ay o f t he m on th 7 6 3 6 6 6 6 6 6 6 6 6 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 W at er d ep th (c m ) 0 0 10 0 0 1 0 0 0 1 1 1 2 2 0 1 1 3 2 4 0 0 0 0 3 4 5 2 0 0 0 0 0 2 2 1 3 2 2 0 0 0 0 0 0 0 0 0 A lti tu de (m ) 39 4 21 7 56 8 21 7 21 7 21 7 21 7 21 7 21 7 21 7 21 7 21 7 20 5 20 5 20 5 20 5 20 5 20 5 20 5 20 5 20 5 20 5 20 5 20 5 19 0 19 0 19 0 19 0 19 0 19 0 19 0 19 0 19 0 19 0 19 0 19 0 19 0 27 3 27 3 19 0 19 0 19 0 37 7 37 7 37 7 37 7 37 7 37 7 C ov er o f h er b la ye r ( % ) 55 60 35 45 60 60 20 55 40 45 30 60 30 45 50 35 70 55 20 30 60 50 55 35 35 30 40 20 40 50 60 70 70 40 50 30 20 70 70 30 30 50 20 35 40 60 15 45 R el ev é ar ea (m 2 ) 3 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 5 5 5 5 5 5 pH 6, 8 – – 7, 0 7, 2 – 7, 3 – – 7, 0 – 6, 9 7, 3 – 7, 2 7, 2 6, 9 – 7, 2 – 7, 0 6, 9 – – 7, 2 6, 9 – – – 6, 9 7, 2 – 7, 0 – 7, 2 7, 0 – – 7, 8 7, 8 7, 8 7, 8 – – 7, 6 – – N um be r o f w ee ds 10 9 8 9 11 11 12 13 10 11 12 13 11 11 9 11 8 9 7 9 9 8 9 8 13 12 11 11 11 14 11 10 9 9 10 12 11 15 16 11 14 14 11 11 11 10 13 12 re l. re l. A ss oc ia tio n/ C om m un ity M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L C M L C M L C M L C M L C M L C M L C M L C M L C 1– 39 40 –4 8 C ul ti va te d pl an t O ry za s at iv a 2 3 3 4 3 3 4 3 4 4 4 3 4 4 4 3 3 3 4 4 3 3 3 4 3 4 4 4 4 4 3 3 3 4 3 4 4 2 3 4 4 4 4 3 2 1 3 3 A ss . M az o pu m ili -L in de rn ie tu m c ili at ae M az us p um ilu s 1 3 + 2 2 1 1 1 1 1 + 1 1 1 3 2 1 1 + 1 2 3 3 2 1 1 + + . + 1 1 + 1 1 + + + 1 1 + + + + + 1 + . V V Li nd er ni a ci lia ta . . . . + 1 1 3 2 3 2 1 1 1 + + 2 1 1 2 2 1 1 1 + . + 1 1 + + 1 2 1 1 + 1 1 + + + 1 + . . . + + V IV Su bA ss . M az o pu m ili -L in de rn ie tu m c ili at ae c ae su lie to su m a xi lla ri s C ae su lia a xi lli ar is . . . . . . . . . . . . . . . . . . . . . + . . . . . . . . . . . . . . . . . 1 + 1 1 2 + 1 1 2 I V A ll. L ud w ig io n hy ss op ifo lio -o ct ov al vi s A lte rn an th er a se ss ili s + + 1 1 1 + + + 1 1 + . 1 2 + 1 2 3 1 + + 1 + 1 1 + 2 1 1 1 1 . . 1 + + 1 1 + 1 1 2 + 1 1 + + 1 V V F im br is ty lis m ili ac ea . + 1 1 + 1 + 1 + + 1 + . . . . 1 + . . . . . . . + . . 1 + + . . . . . . 1 1 + 2 1 1 1 + + . . II I IV M ar si le a m in ut a . . + . . . . . . . + . . + . . . + . + . + + . . . . . . . . + + . . . . . . . . . . . . . . + II I Sp he no cl ea z ey la ni ca . . . . . . . . . . . . . . . . . . . . . . . . + + + 1 . . . . . 2 + 1 + . . . . . . . . . . . II – E la tin e tr ia nd ra 1 . . . . . . . . . . . . . . . . . . . . . . . . . 1 + . . . . . + + . + . . . . . . . . . . . I – C yp er us k yl lin gi a . + 1 1 . . . + . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I – Lu dw ig ia p er en ni s . . . . . . . . . . . . . . . . . . . . . . . . . . . . + . . . + . . + . . . . . . . . . . . . I – A lte rn an th er a ph ilo xe ro id es . . . . . . . . . . . . . . . . + . . . . . . . . . . + . . . . . . . . . . . . . . . . . . . . I – Sp or ad ic s pe ci es : C al lit ri ch e pa lu st ri s va r. or yz et or um 3 8( +) . O . C yp er o- E ch in oc hl oe ta lia o ry zo id is e t C l. O ry ze te a sa tiv ae C yp er us d iff or m is 1 2 2 1 2 1 1 1 + . . 3 + 1 1 1 2 1 + + 1 1 2 1 1 + + . + 1 1 . . 1 + 2 1 1 3 1 + + . . 2 2 . . V II I E ch in oc hl oa c ol on a . . . . . . . . . . . + + 1 + 1 . . . + + . + + + 1 1 + 1 2 3 2 2 . . + + + 1 + + 1 . + + 1 + II I IV C yp er us ir ia 1 . . . 1 + . . . + . . . . . . . . . . . . . . . . . . . 2 1 1 2 1 2 1 1 3 2 . + . + . 1 . 1 1 II II I Sc ir pu s ju nc oi de s + . . . . . . + . . . . . . . . . . . . . . . . . . . . + . . . . . . . . 1 1 + . . + + 1 2 + 1 I IV A m m an ni a ba cc ife ra . . . . . . . . . 1 + 2 . . 1 + . . . . . . . . 1 + 1 1 . . . . . . . . . . . . . . . . . . + II I A m m an ni a m ul tifl o ra . . . . . . . . . . . . . . . + . . . . . . . . + + + + . . . . . . . + . . + . + . . . . . . I II M on oc ho ri a va gi na lis . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 . . . . 1 2 + + . + 1 . . . . . . . . I I Sy ne dr el la n od ifl or a + . . . . . . . . . . . . . . + . . . . . . . + . . . . . . . . . . . . . . . . . . + + . . 1 + I II I P hy lla nt he s fr at er ne s . . . . . . + . . + + 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1 . . . . . . I II Le pt oc hl oa c hi ne ns is . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 + 3 2 . . + . . . . . . . . . . . . I – 1 NOWAK A., NOWAK S., NOBIS M. ACTA BOT. CROAT. 75 (1), 2016 Su cc es si ve n um be r o f r el ev é 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 Constancy Constancy D ay o f t he m on th 7 6 3 6 6 6 6 6 6 6 6 6 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 W at er d ep th (c m ) 0 0 10 0 0 1 0 0 0 1 1 1 2 2 0 1 1 3 2 4 0 0 0 0 3 4 5 2 0 0 0 0 0 2 2 1 3 2 2 0 0 0 0 0 0 0 0 0 A lti tu de (m ) 39 4 21 7 56 8 21 7 21 7 21 7 21 7 21 7 21 7 21 7 21 7 21 7 20 5 20 5 20 5 20 5 20 5 20 5 20 5 20 5 20 5 20 5 20 5 20 5 19 0 19 0 19 0 19 0 19 0 19 0 19 0 19 0 19 0 19 0 19 0 19 0 19 0 27 3 27 3 19 0 19 0 19 0 37 7 37 7 37 7 37 7 37 7 37 7 C ov er o f h er b la ye r ( % ) 55 60 35 45 60 60 20 55 40 45 30 60 30 45 50 35 70 55 20 30 60 50 55 35 35 30 40 20 40 50 60 70 70 40 50 30 20 70 70 30 30 50 20 35 40 60 15 45 R el ev é ar ea (m 2 ) 3 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 5 5 5 5 5 5 pH 6, 8 – – 7, 0 7, 2 – 7, 3 – – 7, 0 – 6, 9 7, 3 – 7, 2 7, 2 6, 9 – 7, 2 – 7, 0 6, 9 – – 7, 2 6, 9 – – – 6, 9 7, 2 – 7, 0 – 7, 2 7, 0 – – 7, 8 7, 8 7, 8 7, 8 – – 7, 6 – – N um be r o f w ee ds 10 9 8 9 11 11 12 13 10 11 12 13 11 11 9 11 8 9 7 9 9 8 9 8 13 12 11 11 11 14 11 10 9 9 10 12 11 15 16 11 14 14 11 11 11 10 13 12 re l. re l. A ss oc ia tio n/ C om m un ity M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L M L C M L C M L C M L C M L C M L C M L C M L C M L C 1– 39 40 –4 8 E cl ip ta p ro st ra ta . . . . . . . . . + + . . . . . . . . . . . . . . . . . . . + . . . . . . . . . . . . . + . . + I II Li nd er ni a an ag al lis . . . . . + . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 + . . . . . . . . . I – Li nd er ni a hy ss op oi de s . . . . . . . . . . . . . . + . . . . . . . . + . . . . . . . . . . . . . . + . . . . . . . . . I – H ed yo tis d iff us a . . . . . . . . . . . . . . . . . . . + . . . . . + . . . + . . . . . . . . . . . . . . . . . . I – Sp or ad ic s pe ci es : D op at ri um ju nc eu m 1 (3 ); E ch in oc hl oa c ru s- ga lli 3 0( +) ; P as pa lu m d is tic hu m 5 (+ ). A cc om pa ny in g sp ec ie s C yn od on d ac ty lo n . 1 + + + 1 + . . . . + . + . + . + 1 + 2 1 + . 1 . . . . . . 1 + . . . . . . . . . 1 + . . . . II I II Ve ro ni ca a na ga lli s- aq ua tic a + 1 . + 1 2 + + 1 . + . . . . . . . + . . . . . . . + . . . . . . . . + . . . . . . 1 + 1 1 + 1 II IV B ac op a pr oc um be ns . . . . . . + + 1 . . + + 1 . . . . . . + + . . + + . . + . . . . . . . . . . 1 . . + 1 + + + + II IV Li nd er ni a pr oc um be ns 1 1 . 2 2 2 1 1 + + 1 . . . . . . . . . . . . . . . . . . 1 1 . . . . . . + 1 . + 1 . . . . . . II II C en te lla a si at ic a . . . . . . . . . . . . . . 1 + + + + 1 + . + . 1 2 1 + . . . . . . . . . + + . + + . . . . . . II II C om m el in a di ffu sa . . . . . . . . . . . . . . . . . . . . . . . . + + 1 + . 1 + 1 1 . + . . . . . + + . . . . . . II II R an un cu lu s sc el er at us . + . + . + + 1 + + . . . . . . . . . . . . . . . . . . . . . . . . . + . . . . . . . . . . . . II – Ve rn on ia c in er ea . . . . . . . . . . . + . . . . . . . . . . . . + . . . + . . . . . . . . 1 + . . . . + . + . . I II Sp ila nt he s ia ba di ce ns is . . . . . . + . . . . . 2 1 . . . . . . + . + . . . . . . + . . . . . . . . . . . . . . . . . . I – C ar yo ph yl la ce ae s p. . . . . . . . . . 1 + + . . . . . . . . . . . . . . . . . . . . . . . . . . . . + + . . . . . . I II Vi ci a hi rs ut a . . . . . . . + + . . . + + . . . . . . . . . + . . . . . . . . . . . . . . . . . . . . . . . . I – Li pp ia n od ifl or a . . . . . . . . . . . . + 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . + 1 I II C he no po di um a lb um . . . . . . . . . . + . + . 1 + . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I – N aj as m in or . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . + . + + . + . . . . . . . . . . . I – Sp ir od el a po ly rr hi za . . . . . . . . . . . + . . . . + + . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I – P ol yg on um b ar ba tu m . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 + . . . . . . . . . I – P lu ch ea in di ca . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . + 1 . . . . . . – II Li m no bi um d ub iu m . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . + + . . . . . . . . . I – E ch in oc hl oa g la br es ce ns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . + + – II Sp or ad ic s pe ci es : C ol oc as ia e sc ul en ta 3 2( +) ; C yp er us o do ra tu s 30 (+ ); C yp er us ro tu nd us 1 3( +) ; J un cu s pr is m at oc ar pu s 5( +) ; N ym ph ae a no uc ha li 12 (+ ); P ol yg on um fl ac ci du m 3 (+ ); V er on ic a be cc ab un ga 8 (+ ). L oc al it y of r el ev é: 1 – (2 74 75 0, 2; 8 45 53 4) ; 2 , 4, 5 , 6 , 7 , 8 , 9 , 1 0, 1 1, 1 2 – (2 73 45 4, 5; 8 42 94 1, 6) ; 3 – (2 74 54 8, 3; 8 50 24 4, 4) ; 1 3, 1 4, 1 5, 1 6, 1 7, 1 8, 1 9, 2 0, 2 1, 2 2, 2 3, 2 4, 2 6, 2 8, 2 9, 3 1, 3 3, 3 5, 3 7, 4 1 – (2 73 45 9, 1; 8 42 93 7, 5) ; 2 5, 2 7, 3 0, 3 2, 3 4, 3 6, 4 0, 4 2 – (2 73 52 2, 3; 8 42 95 4, 5) ; 3 8 – (2 75 24 1, 2; 8 43 54 5, 5) ; 39 – (2 73 75 3, 4; 8 42 93 9, 7) ; 4 3, 4 4, 4 5, 4 6, 4 7, 4 8 – (2 74 80 4, 5; 8 45 20 3, 8) ; 2 WEED COMMUNITIES OF RICE FIELDS IN NEPAL ACTA BOT. CROAT. 75 (1), 2016 O n- lin e Su pp l. Ta b. 2 . C om m un iti es o f t he O ry ze te a sa tiv ae c la ss (p ar t I I) d ur in g th e st ud y, in M ay 2 01 3. R r – R ot al et um ro tu nd ifo lia e, E ta – E la tin et um tr ia nd ro -a m bi gu ae , A p – A m m an ie tu m p yg m ea e, M m – M ar si le et um m in ut ae . T he c ov er -a bu nd an ce s ca le o f B ra un -B la nq ue t ( 19 64 ) w as u se d : r = 1 o r 5 in di vi du al s; + = fe w in di vi du al s (< 2 0) w ith c ov er < 5 % ; 1 = m an y in di vi du al s (2 0– 1 00 ) w ith c ov er < 5 % ; 2 = 5 % –2 5% c ov er ; 3 = 25 % –5 0% c ov er ; 4 = 5 0% –7 5% c ov er ; 5 = 7 5% –1 00 % c ov er . Su cc es si ve n um be r o f r el ev é 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 Constancy Constancy Constancy Number of occurrence D ay o f t he m on th 5 5 5 5 5 5 7 7 7 7 7 7 7 7 7 7 7 7 7 3 3 3 3 3 3 3 3 3 3 3 3 3 3 6 6 6 6 6 7 7 7 7 7 7 7 7 7 7 W at er d ep th (c m ) 1 0 0 0 5 7 15 7 0 1 0 0 0 0 0 1 0 1 3 5 10 2 3 1 3 15 13 1 2 6 8 5 8 1 0 3 4 0 0 0 0 0 3 8 0 0 10 10 A lti tu de (m ) 46 8 46 8 46 8 46 8 46 9 46 9 27 3 27 3 27 3 27 3 35 0 35 0 39 4 39 4 39 4 27 3 27 3 39 4 39 4 56 8 56 8 36 8 36 8 36 8 36 8 36 5 36 5 36 5 36 5 36 5 36 5 36 5 36 5 21 7 21 7 21 7 21 7 21 7 18 4 18 4 18 6 18 6 20 5 20 5 37 7 37 7 20 5 20 5 C ov er o f h er b la ye r ( % ) 85 90 70 45 50 50 90 60 10 40 55 30 70 20 50 45 45 30 35 70 50 75 90 80 60 80 70 45 40 65 50 45 35 40 55 55 70 60 40 20 20 25 25 40 40 50 40 25 R el ev é ar ea (m 2 ) 20 20 15 25 25 25 25 25 3 3 3 3 3 3 3 3 3 5 5 25 25 25 25 25 25 25 25 25 25 25 25 25 25 10 10 5 10 5 20 15 10 25 25 25 5 5 5 5 pH 6, 8 7, 0 7, 2 7, 2 6, 8 7, 2 7, 0 6, 8 6, 8 7, 1 7, 2 7, 1 7, 0 7, 0 7, 2 7, 0 6, 8 6, 4 6, 7 6, 7 6, 4 6, 5 7, 0 – 6, 5 6, 5 6, 7 – 6, 8 6, 7 6, 6 6, 5 6, 4 6, 8 6, 4 7, 1 7, 0 6, 9 6, 9 6, 5 6, 5 – 7, 3 7, 3 7, 0 7, 0 7, 0 7, 0 N um be r o f w ee ds 9 12 13 13 13 14 10 8 7 9 10 10 9 10 8 4 4 9 12 16 11 11 11 15 18 9 8 9 7 8 8 9 10 13 13 14 12 14 11 11 11 10 7 3 5 5 3 3 re l. re l. re l. re l. A ss oc ia tio n/ C om m un ity E ta E ta E ta E ta E ta E ta E ta E ta E ta E ta E ta E ta E ta E ta E ta E ta E ta R r R r R r R r R r R r R r R r R r R r R r R r R r R r R r R r A p A p A p A p A p A p A p A p A p M m M m M m M m M m M m 1– 17 18 –3 3 34 –4 2 44 –4 8 C ul tiv at ed p la nt O ry za s at iv a 2 2 3 3 3 4 2 3 3 3 3 3 3 3 3 3 2 3 3 3 3 2 2 2 3 2 3 3 3 3 3 3 3 3 2 3 3 3 3 3 4 4 3 3 2 2 3 3 V A ss . E la tin et um tr ia nd ro -a m bi gu ae E la tin e tr ia nd ra 4 4 1 1 + . 4 3 1 1 3 2 2 1 2 3 3 + + . . . . . . . . . . . . . . . . . . . . . . . . . . . . . V I – – E la tin e am bi gu a 2 3 3 2 1 2 . . . 1 . . 1 + . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . II I – – – A ss . R ot al et um r ot un di fo lia e R ot al a ro tu nd ifo lia . . . . . . . . . . . . . . . . . 2 2 3 2 1 2 1 1 2 3 1 2 2 1 1 + . . . . . . . . . . . . . . . – V – – A ss . A m m an ie tu m p yg m ea e A m m an ia p yg m ae a . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 . . 1 + + 1 1 + . . . . . . – – IV – D ic ho st yl is m ic he lia na . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . + 2 3 1 2 + . . . . . . . . . – – IV – C al lit ri ch e pa lu st ri s v ar . o ry ze to ru m . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 + + + . . . + . . . . . . – – II I – A ss . M ar si le et um m in ut ae M ar si le a m in ut a . . . . . . . . . . . . . . . . . . . 2 + . . + 1 . . . . . . + . . . . . . . . . . 2 3 3 3 3 2 II – 6 A ll. L ud wi gi on h ys so pi fo lio -o ct ov al vi s A lte rn an th er a se ss ili s + + + 1 + 1 1 + + 1 + + 2 1 . + + 1 1 1 + . . + 1 + 1 1 1 . + . . . . . . . 2 1 1 1 + + + 1 . . V IV II I 4 M az us p um ilu s . + . + . . . . . . . . . . + + . . . . . + 1 1 + . . + . . . . . + + 1 1 + 1 + + 1 . . . . . . II II V – F im br is ty lis m ili ac ea . . . + . . . . + + . . . . . . . . . + + + + . . . . . . + . . + . + + + 1 + 1 . . . . + 1 . . I II IV 2 C yp er us k yl lin gi a . . . . . . . . . . . . . . . . . . . . + . . + + . . . . . . . . . . . . . . . + . . . . . . . – I I – Lu dw ig ia p er en ni s . . . . . . . . . + . . . . . . . . . . . + + . . . . . . . . . . . . . . . . . . . . . . . . . I I – – Li nd er ni a ci lia ta . . + . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . + . . . . . . . . . . . . I – I – Sp or ad ic s pe ci es : L ud w ig ia h ys so pi fo lia 2 0( 1) ; L ud w ig ia o ct ov al vi s 20 (+ ). O . C yp er o- E ch in oc hl oe ta lia o ry zo id is e t C l. O ry ze te a sa tiv ae C yp er us d iff or m is . . + . . . 1 2 . . 2 1 1 + 1 . . 1 1 1 1 . . 3 2 . . . . . . . . 2 + 1 . . . . + 1 1 + + . . . II I II II I 3 E ch in oc hl oa c ol on a . . . . . . + . + . + + + + 1 + + . . . . . . . . . . . . . 1 2 1 1 1 1 + + . . . . . 1 + II I I V 2 D op at ri um ju nc eu m + 1 1 + + + . . . . . . 1 + 2 . . . . . . . . + + 1 1 2 1 2 2 . . . . . . . . . . . . . . . . . II I II I – – M on oc ho ri a va gi na lis + + . . 3 2 . . . . . . . . . . . . . . . . . 1 + 1 + + + + + . . . . . . . + + . . . . . . II II I II – C yp er us ir ia . . . . . + + . . . . . . + + . . + 1 + . . . . . . . . . . . . . . . . + 1 + . 1 1 . . . . . . II I II I – Li nd er ni a an ag al lis . . . . . . + + 1 2 . . . . . . . . . + + 2 1 1 + . . . . . . . . . . . . . . . . . . . . . . . II II – – Li nd er ni a an tip od a + 1 . + + . . . . . . . . . . . . . . . . . . . . . . . . + + 1 2 . . . . . . . . . . . . . . . II II – – E cl ip ta p ro st ra ta . . 1 + . . + + . . . . . . . . + . . . . . . . + . . . . . . . . . . . + + . . . . . . . . . . II I II – Sc ir pu s ju nc oi de s . . + + 1 1 1 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . II – – – P hy lla nt he s fr at er ne s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . + + 1 . . + + . . + . . . . . – – II I 1 3 NOWAK A., NOWAK S., NOBIS M. ACTA BOT. CROAT. 75 (1), 2016 Su cc es si ve n um be r o f r el ev é 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 Constancy Constancy Constancy Number of occurrence D ay o f t he m on th 5 5 5 5 5 5 7 7 7 7 7 7 7 7 7 7 7 7 7 3 3 3 3 3 3 3 3 3 3 3 3 3 3 6 6 6 6 6 7 7 7 7 7 7 7 7 7 7 W at er d ep th (c m ) 1 0 0 0 5 7 15 7 0 1 0 0 0 0 0 1 0 1 3 5 10 2 3 1 3 15 13 1 2 6 8 5 8 1 0 3 4 0 0 0 0 0 3 8 0 0 10 10 A lti tu de (m ) 46 8 46 8 46 8 46 8 46 9 46 9 27 3 27 3 27 3 27 3 35 0 35 0 39 4 39 4 39 4 27 3 27 3 39 4 39 4 56 8 56 8 36 8 36 8 36 8 36 8 36 5 36 5 36 5 36 5 36 5 36 5 36 5 36 5 21 7 21 7 21 7 21 7 21 7 18 4 18 4 18 6 18 6 20 5 20 5 37 7 37 7 20 5 20 5 C ov er o f h er b la ye r ( % ) 85 90 70 45 50 50 90 60 10 40 55 30 70 20 50 45 45 30 35 70 50 75 90 80 60 80 70 45 40 65 50 45 35 40 55 55 70 60 40 20 20 25 25 40 40 50 40 25 R el ev é ar ea (m 2 ) 20 20 15 25 25 25 25 25 3 3 3 3 3 3 3 3 3 5 5 25 25 25 25 25 25 25 25 25 25 25 25 25 25 10 10 5 10 5 20 15 10 25 25 25 5 5 5 5 pH 6, 8 7, 0 7, 2 7, 2 6, 8 7, 2 7, 0 6, 8 6, 8 7, 1 7, 2 7, 1 7, 0 7, 0 7, 2 7, 0 6, 8 6, 4 6, 7 6, 7 6, 4 6, 5 7, 0 – 6, 5 6, 5 6, 7 – 6, 8 6, 7 6, 6 6, 5 6, 4 6, 8 6, 4 7, 1 7, 0 6, 9 6, 9 6, 5 6, 5 – 7, 3 7, 3 7, 0 7, 0 7, 0 7, 0 N um be r o f w ee ds 9 12 13 13 13 14 10 8 7 9 10 10 9 10 8 4 4 9 12 16 11 11 11 15 18 9 8 9 7 8 8 9 10 13 13 14 12 14 11 11 11 10 7 3 5 5 3 3 re l. re l. re l. re l. A ss oc ia tio n/ C om m un ity E ta E ta E ta E ta E ta E ta E ta E ta E ta E ta E ta E ta E ta E ta E ta E ta E ta R r R r R r R r R r R r R r R r R r R r R r R r R r R r R r R r A p A p A p A p A p A p A p A p A p M m M m M m M m M m M m 1– 17 18 –3 3 34 –4 2 44 –4 8 C yp er us p ul ch er ri m us . + 2 1 + 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . II – – – F im br is ty lis s to lo ni fe ra . . . . . . . . . . . . . . . . . . . . . 1 + 1 + . . . . . . . . . . . . . . . . . . . . . . . – II – – H ed yo tis d iff us a . . . . . + 1 + . . . . . . . . . . . . . . + . . . . . . . . . . . . . . . . . . . . . . . . . I I – – Sy ne dr el la n od ifl or a . . . . . . . . . . 1 + . . + . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I – – – A m m an ni a ba cc ife ra . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 . . + + . . . . . . . . . . – – II – A m m an ni a m ul tifl o ra . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . + + . . . + . . . . . . . . – – II – H ym en ac hn e ac ut ig lu m a . . . . + + . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I – – – Sp or ad ic s pe ci es : E ch in oc hl oa o ry zo id es 2 1( +) ; E le oc ha ri s re tr ofl e xa 3 6( +) ; L ep to ch lo a ch in en si s 40 (+ ). A cc om pa ny in g sp ec ie s C en te lla a si at ic a 1 + 1 1 1 + 2 1 + 1 . . 1 1 . . . . . . . . . + + 3 2 1 + 2 2 2 1 . . . . . . . + + + . . . + 1 IV IV II 3 C yn od on d ac ty lo n . + + + + + . . . . . . . . . . . . + . 1 2 3 + 1 + + + 1 . . + 1 + + + . . . . . . + . + + . . II IV II 3 Li nd er ni a pr oc um be ns . . . . . . . . . . + + 2 1 1 . . + + . . . . . . . . . . . . . . . 1 + 2 1 1 + 1 1 . . . . . . II I V – Ve ro ni ca a na ga lli s- aq ua tic a . . . . . + . . . . . . . . . . . . . . . . . . + . . 1 1 1 + 1 1 + 1 . . . . . . . . . . . . . I II I II – Ve rn on ia c in er ea . . . . . . . . . . . + . . + . . . + . . . . . . . . . . . . . . + + 1 . + 1 1 . . . . . + . . I I IV 1 Ju nc us p ri sm at oc ar pu s . . + 1 1 + . . . . . . . . . . . . . . . 1 + 1 + . . + . . . . . . . . . . . . . . . . . . . . II II – – P ol yg on um v is co su m 1 + . . . . . . . . . . . . . . . . . . . . . + . . . . . + 1 1 + . . . . . . . . . . . . . . . I II – – B ac op a pr oc um be ns . . . . . . . . . . + + . . . . . + + . . . . . . . . . . . . . . 1 . . + 1 . . . . . . . . . . I I II – C om m el in a di ffu sa . . . . . . . . . . + + 1 + . . . + + + . . . . . . . . . . . . . . . . . . . . . . . . . . . . II I – – Ve ro ni ca b ec ca bu ng a . . . . . . . . . . . . . . . . . . . + 2 2 3 3 2 . . . . . . . . . . . . . . . . . . . . . . . – II – – Sp ila nt he s ia ba di ce ns is + . . . . . . . . . . . . . . . . . . . . + . . + + . . . . . 1 + . . . . . . . . . . . . . . . I II – – P ol yg on um b ar ba tu m . . . . . . . . . + + 1 . . . . . + + . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I I – – N aj as m in or . . . . . . . . . . . . . . . . . . . . . . . . + 1 1 . . . . . + . . . . . . . . . . . . . . . – II – – P ol yg on um fl ac ci du m . . . . . . . . . . . . . . . . . . . + + . . . + . . . . . . . . . . . . . . . . . . . . . . . – I – – C ar yo ph yl la ce ae s p. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . + . . . . . . + + . . . . . . – – II – C yp er us d iff us us . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2 . . . . . . . . . . – – II – A lg ae in de t. . . . . . . . . . . . . . . . . . . . . . . . . . 2 1 . . . . . . . . . . . . . . . . . . . . . – I – – Le er si a he xa nd ra . . . . + 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I – – – A re na ri a se rp yl lif ol ia . . . . . . . . . . . . . . . . . . . . . + 1 . . . . . . . . . . . . . . . . . . . . . . . . . – I – – H yp er ic um ja po ni cu m . . . . . . . . + + . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I – – – R um ex d en ta tu s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . + . . . + . . . . . . . . . . – – II – Vi ci a hi rs ut a . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . + + . . . . . . . . . . . . – – II – E up ho rb ia h ir ta . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . + + . . . . . . . . – – II – Sp or ad ic s pe ci es : A zo lla fi lic ul oi de s 20 (+ ); B lu m ea la ci ni at a 20 (+ ); C yp er us ro tu nd us 4 3( +) ; H ed yo tis r ac em os a 3( +) ; L im no ch ar is fl av a 20 (1 ); L in de rn ia v is co sa 2 (+ ); P or tu la ca o le ra ce a 11 (+ ); S pi ro de la p ol yr rh iz a 20 (1 ); V al lis ne ri a sp ir al is 2 4( +) . L oc al it y of r el ev é: 1 , 4 , 6 , 2 2, 2 3, 2 4, 2 5, 2 6, 2 9, 3 1, 3 3 – (2 75 44 3, 3; 8 43 11 2, 1) ; 2 , 3 , 5 – (2 80 63 7, 2; 8 35 23 5, 2) ; 7 , 1 0, 1 6, 4 1, 4 2 – (2 73 75 3, 4; 8 42 93 9, 7) ; 8 , 9 , 1 7 – (2 75 24 1, 2; 8 43 54 5, 5) ; 1 1, 1 2 – (2 74 84 9, 1; 8 44 71 3, 9) ; 1 3, 1 4, 1 5, 1 8, 1 9 – (2 74 75 0, 2; 84 55 34 ); 2 0, 2 1 – (2 74 54 8, 3; 8 50 24 4, 4) ; 2 7, 2 8, 3 0, 3 2 – (2 75 91 6, 1; 8 41 64 9, 9) ; 3 4, 3 5, 3 6, 3 7, 3 8 – (2 73 45 4, 5; 8 42 94 1, 6) ; 3 9, 4 0 – (2 73 61 6, 5; 8 43 03 8, 3) ; 4 3, 4 4, 4 7, 4 8 – (2 73 45 9, 1; 8 42 93 7, 5) ; 4 5, 4 6 – (2 74 80 4, 5; 8 45 20 3, 8) . 4