Folia Geobot https://doi.org/10.1007/s12224-020-09370-8 Vascular plant diversity along an elevational gradient in the Central Himalayas, western Nepal Chandra K. Subedi & Maan B. Rokaya & Zuzana Münzbergová & Binu Timsina & Janita Gurung & Nakul Chettri & Chitra B. Baniya & Suresh K. Ghimire & Ram P. Chaudhary Received: 22 May 2019 / Revised: 23 December 2019 / Accepted: 23 May 2020 # Institute of Botany, Czech Academy of Sciences 2020 Abstract Elevational gradients are linked with different abiotic and biotic factors, which in turn influence the distribution of plant diversity. In the present study we explored the relative importance of different environmental factors in shaping species diversity and composition of vascular plant species along an elevational gradient in the Chamelia Valley, Api-Nampa Conservation Area in western Nepal. Data were collected from 2,000 to 3,800 m above sea level and analysed using a generalized linear mixed model (GLM) and non-metric C. K. Subedi (*) : R. P. Chaudhary Research Centre for Applied Science and Technology, Tribhuvan University, Kirtipur 44600, Nepal e-mail: chandraks2000@yahoo.com M. B. Rokaya : Z. Münzbergová Institute of Botany, Czech Academy of Sciences, Zámek 1, 252 43 Průhonice, Czechia M. B. Rokaya : B. Timsina Department of Biodiversity Research, Global Change Research Centre, Czech Academy of Sciences, Bělidla 4a, 603 00 Brno, Czechia multidimensional scaling (NMDS). We recorded 231 vascular plant species consisting of 158 herb species belonging to 55 families, 37 shrub species belonging to 22 families and 36 tree species belonging to 23 families. Species richness and species abundance significantly decreased with increasing elevation. However, species richness increased with the intensity of vegetation cutting. Species richness and abundance also increased with increased annual precipitation and mean annual temperature whereas species abundance decreased with grazing, soil phosphorus and nitrogen. NMDS ordination revealed that mean annual temperature and annual precipitation affect the composition of vascular plant species in opposite ways to elevation. Among the many anthropogenic disturbances, only grazing affected species composition. In conclusion, more than one environmental factor contribute to the shaping of patterns of vascular plant species distribution in western Nepal. Knowledge on species diversity, distribution and underlying factors needs to be taken into consideration when formulating and implementing conservation strategies. Z. Münzbergová : B. Timsina Department of Botany/Institute of Environmental Studies, Faculty of Science, Charles University, Benátská 2, 128 01 Prague, Czechia Keywords disturbance . soil nutrients . species abundance . species composition . species richness J. Gurung : N. Chettri International Centre for Integrated Mountain Development, Khumaltar, Lalitpur, Nepal Introduction C. B. Baniya : S. K. Ghimire Central Department of Botany, Tribhuvan University, Kirtipur 44600, Nepal Mountain regions have a unique biodiversity due to environmental heterogeneity and variation in the landscape (Körner 2003). Elevational gradients are the major Subedi et al. ecological factor shaping spatial distribution of different species, including plants (Kluge et al. 2017). The effect of elevation is often linked to the variation in numerous abiotic and biotic factors, which in turn affect the distribution of different plant species (Kluge et al. 2017). It is therefore important to know how biotic factors (such as canopy cover, competition, herbivore damage, disturbance and grazing – Bhatta et al. 2015; Adhikari et al. 2017) and abiotic factors (such as temperature, precipitation and soil properties – Díaz et al. 1999; Laughlin and Abella 2007) affect distributional patterns of plant species along elevational gradients (Körner 2007). Generally, abiotic factors explain a higher proportion of variation in species composition in colder climate zones whereas in warmer climates biotic factors explain more variation (Laughlin and Abella 2007; Klanderud et al. 2015). Among biotic factors, anthropogenic disturbances are the major ones affecting plant diversity and community composition (Harrelson and Matlack 2006) by favouring stress-tolerant species (Laughlin et al. 2005). According to the intermediate disturbance hypothesis (Fox 1979), species diversity is maximum when ecological disturbance (either natural or anthropogenic) is neither too rare nor too frequent (Molino and Sabatier 2001; Huston 2014; Yuan et al. 2016). The importance of disturbances, however, varies between localities (Bongers et al. 2009). Likewise, different abiotic factors, such as temperature, precipitation, soil nutrients and soil pH, affect productivity, which ultimately determine the carrying capacity of a particular area. This results in specific patterns of plant species diversity (Amjad et al. 2014; Peters et al. 2016) at local or regional scales (Zellweger et al. 2016). There are some empirical studies on patterns of plant species distribution along elevational gradients in Nepal, studying ferns (Bhattarai et al. 2004), trees (Bhattarai and Vetaas 2006) and vascular plants (Panthi et al. 2007). Some studies have also covered sub-alpine forest border ecotone species (Shrestha and Vetaas 2009), woody plant species under different types of land use and on different slopes in transHimalayan valleys in central Nepal (Paudel and Vetaas 2014), plant species richness of different lifeforms along a subtropical elevational gradient in eastern Nepal (Bhattarai and Vetaas 2003), and variation in forest biodiversity in central Nepal (Christensen and Heilmann-Clausen 2009). There is, however, limited research from western Nepal (Bhattarai et al. 2014). We therefore explored the effects of biotic and abiotic factors on species richness, abundance and composition of vascular plant species along an elevational gradient in western Nepal. The purpose was to provide further insights into distribution patterns of plant species along an elevational gradient (in a temperate region) in a less explored area in western Nepal. Specifically, we asked the following questions: (1) Do species richness, abundance and composition of different vascular plant species vary along the elevational gradient? (2) What are the different environmental factors responsible for shaping the patterns of richness, abundance and composition of vascular plant species after accounting for elevation? To answer these questions, we collected data on vascular plant species from 2,000 to 3,800 m a.s.l. in western Nepal and tested for the effects of abiotic and biotic factors on richness, abundance and composition of these plant species. Material and methods Study area The study was conducted in the Chamelia Valley (Fig. 1) located in the Api-Nampa Conservation Area (ANCA; 29°30′ – 30°15′ N and 80–81°09′ E) in the Darchula district in western Nepal. The ANCA covers an area of 1,903 km2 with an elevation range from 518 to 7,132 m a.s.l. Climate conditions vary from subtropical to alpine. The average maximum annual temperature of the area is 18.6°C, the minimum annual temperature is 7.7°C, and average annual precipitation is 2,129 mm (DoHM 2017). Vegetation in the ANCA is characterized by lower-temperate mixed broad-leaved forest (2,000–2,300 m a.s.l.), temperate mixed broadleaved forest (2,400–2,600 m a.s.l.), upper temperate mixed broad-leaved forest (2,700–3,200 m a.s.l.) and birch-rhododendron forest (3,300–3,800 m a.s.l.). Data for our study were collected in the Chamelia Valley at an interval of 100 m elevation from Khayakot (2,000 m a.s.l.) to Shiyela (3,800 m a.s.l.). Vegetation sampling Our study only covered the elevation range from 2,000 to 3,800 m a.s.l. because below 2,000 m a.s.l. there was an agricultural field and above 3,800 m a.s.l. there Vascular plant diversity along an elevational gradient in the Central Himalayas, western Nepal 81°0'0"E 30°10'0"N 150 60 75 36 INDIA INDIA 0 34 N E P A L 3608 4292 43 . CHINA 38 INDIA 80°50'0"E 44 80°40'0"E 30°10'0"N 80°30'0"E 47 300 kms 27 3862 64 3822 47 30°0'0"N 30°0'0"N 428 9 1:10,000,000 4814 3868 0 1 2 4 kms 29°50'0"N 29°50'0"N 1:130,000 Legend Sampling Plots River Api-Nampa Conservation Area Boundary Landuse/Landcover Class Agriculture Forest Grassland Rock/barren land 29°40'0"N 5 10 20 kms 1:350,000 80°30'0"E 80°40'0"E 80°50'0"E 29°40'0"N Scrub 0 Settlement Snow and glaciers Waterbody 81°0'0"E Fig. 1 Study area in the Chamelia Valley, western Nepal was no forest. We carried out the field work during June and August 2014. We laid transects of 160 m at each study elevation comprising six quadrats (plots) of size 10 m × 10 m. The quadrats were 20 m apart from one another (Appendix Fig. 1). In total we used 19 transects with 114 quadrats along the elevational gradient. The presence or absence of different vascular plant species were recorded in each quadrat. All plant species were collected, kept between newspaper sheets, pressed by herbarium press and dried in sunlight (Forman and Bridson 1989). The collected species were later identified with the help of available literature (Sharma and Kachroo 1983; Polunin and Stainton 1984; Stainton 1988; Watson et al. 2011). We followed Press et al. (2000) for the species nomenclature. In addition to recording vascular plant species in each quadrat, we noted the elevation by using an altimeter (Sunto), longitude and latitude by using a portable global positioning system (GPS) receiver (eTrex Vista, Garmin), and slope and aspect by using a compass (Sunto). Annual precipitation and mean annual temperature were obtained from WorldClim version 1.4 (www.worldclim.org – Hijmans et al. 2005). Anthropogenic variables As our study area was easily accessible from nearby villages, we predicted that human disturbance could play a vital role in maintaining patterns of species diversity. Therefore, disturbances such as grazing and cutting were visually estimated in each quadrat under study. They were recorded on a scale ranging from 0 (no disturbance) to 3 (highest level of disturbance). Soil sampling and laboratory analysis Top soil (0–10 cm) was collected from the centre of each 10 m × 10 m quadrat (i.e. 114 quadrats in total). Soil samples were stored separately in zip-lock plastic bags (Carter and Gregorich 2008) and transported to Kathmandu for analysis. In Kathmandu, soil was air- Subedi et al. dried and then analysed at the Soil Science Division, National Agriculture Research Centre (NARC), Khumaltar, Lalitpur, Nepal. Soil pH was determined in a 1:2 soil: water suspension and measured with a pH meter using a calomel electrode assembly (John et al. 2007). Soil organic carbon (SOC) was determined using the Walkley– Black method (Walkley and Black 1934), total nitrogen (N) using the Kjeldhal method (Jacobs 1951), and available phosphorus (P) and potassium (K) using the modified Olsen's bicarbonate method and a flame photometer, respectively (Walkley and Black 1934). Statistical analysis Data were analysed using three terms: species richness, abundance and composition. Plant species richness refers to the number of species in each sampling plot. Abundance of each species in each plot refers to the occurrence of the species in four subplots on the scale of 0 (if absent from all subplots) to 4 (if present in all four subplots). Species composition refers to the type of species encountered in each plot (Timsina et al. 2016). We used Spearman’s rank correlation in R (R Development Core Team 2019) to determine the relationships among different environmental variables. To determine the effect of environmental variables (elevation, grazing, cutting, pH, SOC, total N, P, K, annual precipitation and mean annual temperature) on species richness, we used a generalized linear model (GLM) in R (R Development Core Team 2019). In the model, we first determined the effect of elevation and, if found significant, it was used as a covariate in subsequent analyses. Patterns in plant species composition in different elevational bands were analysed by the non-metric multidimensional scaling (NMDS) ordination method. NMDS is an indirect gradient analysis that performs a certain number of random iterations until a convergent value of stress is obtained. It was applied to the whole samples-by-species data matrix of Bray-Curtis dissimilarity distances. NMDS ordination was performed using the package ‘vegan’ with the function ‘metaMDS’ (Oksanen et al. 2019). Significant environmental variables were overfitted to the model. Final NMDS result with sample plots of varied abundance sample scores were fitted with significant environmental variables using the package ‘ggplot2’ (Wickham 2016). Results Elevation had significant negative correlations with cutting, annual precipitation and mean annual temperature. Cutting was positively correlated with grazing intensity. Carbon was positively correlated with total nitrogen. Available potassium was positively correlated with available phosphorus. Annual precipitation and mean annual temperature were also highly correlated with each other (Table 1). In total, we recorded 231 plant species consisting of 158 herb species belonging to 55 families, 37 shrub species belonging to 22 families and 36 tree species belonging to 23 families (Appendix Table 1). Vascular Table 1 Correlations of environmental variables. Values marked in bold are significant at P < 0.05, N = 456. Grazing Cutting pH Potassium Elevation 0.02 −0.26 −0.10 0.18 −0.12 −0.01 0.04 −0.95 −0.96 Grazing 1.00 0.27 −0.02 0.17 0.10 0.10 0.05 0.10 0.05 1.00 0.00 0.01 −0.01 0.13 0.17 0.20 0.24 1.00 −0.04 −0.10 0.01 −0.02 0.05 0.03 1.00 0.19 −0.01 0.02 −0.16 −0.19 1.00 −0.04 −0.08 0.12 0.09 1.00 0.88 0.01 0.02 1.00 −0.04 −0.03 1.00 0.98 Cutting pH Potassium Phosphorus Nitrogen Carbon Annual precipitation Phosphorus Nitrogen Carbon Annual precipitation Mean annual temperature Vascular plant diversity along an elevational gradient in the Central Himalayas, western Nepal plant species richness and abundance significantly decreased with increasing elevation (Fig. 2, Table 2). However, the greatest species richness and species abundance was actually observed at 2,500 m a.s.l. and at 2,300 m a.s.l, respectively (Fig. 2, Table 2). Species richness increased significantly with increasing intensity of vegetation cutting (Fig. 3) and also with an increase in annual precipitation and mean annual temperature (Table 2). Plant abundance decreased with increasing grazing intensity (Fig. 4), soil phosphorus and total nitrogen (Table 2). Species abundance increased with increasing soil potassium, annual precipitation and mean annual temperature (Table 2). Convergence of NMDS ordination was confirmed by obtaining stress value of 0.2 on the whole sample by species dataset. Vector fitting of environmental variables on samples by species dataset revealed that elevation, grazing, mean annual temperature and annual precipitation were significant (Table 3, Fig. 5). Elevation governed the significantly high NMDS1 score value of 0.967 (P < 0.001, R2 = 0.93, Table 3). Mean annual temperature and annual precipitation were significantly negative with NMDS1 (P = 0.001, R2 = 0.906 and P = 0.001, R2 = 0.868 for both variables, respectively). The highest compositional abundances of species was found towards the high amount of mean annual temperature and annual precipitation gradients which were at lower elevations (negative end of NMDS1). Similarly, fewer number of species had high compositional abundances Fig. 2 Relationship between plant species richness, species abundance and elevation of vascular plant species towards high elevation (positive end of NMDS1). Relatively, a small number of species had high compositional abundance at negative end of NMDS2 which was a grazing gradient (P = 0.039, R2 = 0.060). Conversely, the compositional abundance was high in plots where there was no grazing and cutting, that is, the positive end of NMDS2 (Table 3, Fig. 5). Discussion Our present study indicates that there is a significant positive correlation between carbon and nitrogen because both soil carbon and nitrogen availability are mainly determined by the quantity of organic matter in the form of dead plants and animal debris in the ground (Aber and Melillo 2001). Similar findings have also been reported from moist temperate forests of Garhwal Himalaya, India (Gairola et al. 2012). There was a monotonic decrease in species richness and abundance of vascular plant species along our elevational gradient in western Nepal. This decreasing pattern of species along the elevational gradient corroborates many previous studies from different parts of the world (Rahbek 2005; Sahu et al. 2008), including Nepal (Rokaya et al. 2012; Li and Feng 2015). However, there were differences in the details of the decline because of the variation in study sites (Baniya et al. 2012). In our study, the maximum number of vascular plant species Subedi et al. Table 2 The species richness part presents the results of generalized linear model (GLM) tests showing the associations between species richness and species abundance for all vascular plant D.f. species and different environmental variables (elevation, grazing, trampling, cutting, lopping, pH, potassium, phosphorus, nitrogen and carbon). Significant P-values are marked in bold. Species richness P Species abundance R2 P R2 Elevation 1 < 0.001 0.224 < 0.001 0.161 Grazing 3 0.543 – < 0.001 0.048 Cutting 3 0.029 0.033 < 0.001 0.036 pH 1 0.572 – 0.402 – Potassium 1 0.057 – 0.016 0.010 Phosphorus 1 0.092 – 0.010 0.012 Nitrogen 1 0.164 – 0.043 0.007 Carbon 1 0.259 – 0.851 – Annual precipitations 1 0.031 0.017 0.004 0.015 Mean annual temperature 1 0.001 0.043 < 0.001 0.033 was precisely at 2,500 m a.s.l. whereas in other studies (Grytnes and Vetaas 2002; Christensen and HeilmannClausen 2009) this occurred between 1,500 and 2,500 m a.s.l. This shows that the distribution pattern of vascular plant species in western Nepal is partly represented by all vascular plant species in Nepal. As expected, there was great vascular plant species richness at lower elevations compared to higher elevations because of variation in precipitation and temperature. The decrease in species richness with increasing elevation is related to the harsh climate and unfavorable physiography towards the higher elevations (Rokaya et al. 2012). Fig. 3 Relationship between species abundance of vascular plant species and cutting intensity Environmental harshness at high elevations is a result of lower temperatures and increased solar radiation (Körner 2007), decreased soil fertility (Drollinger et al. 2017; Halbritter et al. 2018), and also the presence of steep, rugged topography with little top soil (Miehe et al. 2015). The pattern of increased species diversity with increasing vegetation cutting occurs when cutting trees and shrubs exposes understorey vegetation to sunlight, which makes it grow more vigorously (Abella and Springer 2015). Although partial cutting is beneficial for the growth of plant species, cutting of vegetation on Vascular plant diversity along an elevational gradient in the Central Himalayas, western Nepal Fig. 4 Relationship between species abundance and grazing intensity larger scales has a negative impact on plant diversity (Santaniello et al. 2016). Decreased species abundance with increasing grazing level has also been reported from other parts of the world, but only in arid conditions and not in moist conditions (de Bello et al. 2007). Our study site was neither in a moist nor in a dry area; it falls under the montane belt of the Himalayas, characterized by moderate warmth and higher humidity. The study site was also situated along the way to a summer pastureland where herders let their animals graze for a few days Table 3 Results of NMDS ordination of the samples-by-species dataset. Presented are scores on the NMDS1 and NMDS2 axes, significance values and coefficients of determination for the environmental variables examined. Significant P-values are marked in bold. Variable NMDS1 NMDS2 P R2 Elevation 0.967 −0.256 0.001 0.935 Grazing 0.011 −1.000 0.039 0.060 Cutting −0.962 0.274 0.053 – pH −0.299 0.954 0.782 – Potassium 0.905 −0.425 0.063 – Phosphorus −0.311 0.950 0.243 – Nitrogen −0.140 −0.990 0.677 – Carbon 0.995 0.096 0.939 – Annual precipitations −1.000 0.026 0.001 0.868 Mean annual temperature −0.999 0.054 0.001 0.906 while moving up during May and down during September. Different plant species are mostly in their budding stages during May and their destruction by grazing may have serious effects on seed formation. Zhao et al. (2019) also reported that grazing limited plant buds and long-term grazing exclusion significantly increased plant buds. Our study does not support the intermediate disturbance hypothesis, because there is no maximum species diversity in neither undisturbed nor in highly disturbed sites (Fox 1979). This is probably caused by different grazing or cutting patterns in our study site than where the theory was tested (Bongers et al. 2009). People have been practising a traditional system of grazing system at our study site. Globally, soil nutrients affect plant diversity and community composition (Gilliam and Dick 2010; Lin et al. 2013). In our study, vascular plant species richness decreased with increased phosphorus, potassium and nitrogen. Similar findings have been made by other studies in the case of phosphorus but not for potassium and nitrogen (Wassen et al. 2005; Merunková and Chytrý 2012). In a different study, there was a positive correlation between herb species richness and nutrients such as nitrogen and phosphorus (Bartels and Chen 2010). Such dissimilarities could be caused by variation in sampling strategy, physiography and climatic conditions between our study and other studies. However, plant diversity should significantly increase with increasing amounts of soil nutrients, as high soil nutrients improve plant growth (Denslow 1987). Our results showing lower species Subedi et al. Fig. 5 Effect of different environmental variables on the composition of all plant species, analysed by NMDS. Only significant variables are shown richness in nitrogen-rich environments are quite surprising because nitrogen has been repeatedly demonstrated to increase plant growth (Huston 1980; Lawlor et al. 2001). However, there was variation in loss of species richness in different habitats in Britain (Maskell et al. 2010). It has been explained that there is a reduction in species richness because of soil acidification associated with increased N deposition. Acids are formed due to oxidation of NO2 to NO3− or NH4+ to NO3−. Having a negative correlation between plant diversity and phosphorus is also a result of phosphorus deposition leading to soil acidification. Elevation contributed greatly to the composition of plant species like in other studies (Panthi et al. 2007; Christensen and Heilmann-Clausen 2009; Timsina et al. 2016). Among disturbance variables, grazing also significantly contributed to the variation in species composition. The negative correlation of elevation with temperature and precipitation is similar to one study conducted in China (Li et al. 2009). The contribution of temperature and precipitation to the shaping of the composition of vascular plant species was obvious because the present study was carried out at a site with high abundances of species where there was high mean annual temperature and annual precipitation (Panthi et al. 2007). Anthropogenic disturbances often suppress recruitment, survival and growth of plant species by modifying the soil seed bank and soil nutrition (Khurana and Singh 2001). However, in our study soil nutrients did not affect species composition, meaning that ongoing anthropogenic disturbances are more important in shaping the species composition of vascular plant species in western Nepal. Implication for biodiversity conservation Different environmental factors play important roles in the distribution of plant species in the Chamelia Valley, western Nepal. Among different biotic factors, anthropogenic disturbance is the most important factor that influences plant diversity. Since the livelihoods of mountain people rely on forest resources, mainly for timber, fuel-wood, non-timber forest products and cattle grazing, the human dimension must be taken into account when declaring certain areas as protected areas for conservation and development activities. Cutting and grazing are the major anthropogenic disturbances in forest areas resulting in immense pressure on plant diversity in the ANCA. In the long term, such disturbances will affect ecosystem health and resilience. The present study area, which is located along the way to summer pasture-lands is impacted by residents of nearby villages, medicinal plant collectors and cattle grazers. Clearance of natural vegetation by human activities not Vascular plant diversity along an elevational gradient in the Central Himalayas, western Nepal only leads to the destruction of natural forests, but also to the introduction of invasive species. Invasive species are potential threats to local and regional biodiversity. Therefore, further studies should be carried out to ascertain the impacts of human disturbances on different plant species along with biodiversity in general. It is also necessary to provide alternative resources in order to reduce the dependence of local communities on forestry, as socio-ecological dimensions are important for developing future conservation strategies. Conclusion We studied vascular plant species diversity and composition along an elevational gradient in the Chamelia Valley in western Nepal. Species diversity patterns (species richness, abundance and composition) were affected by different abiotic and biotic factors. Accounting for environmental factors is therefore necessary for better understanding the spatial distribution of plant species. Knowing patterns of species diversity is important when Appendix Appendix Fig. 1. Sampling design for the vegetation survey in the Chamelia Valley, western Nepal. formulating future strategies for plant and biodiversity conservation. Acknowledgements This study was supported by the Kailash Sacred Landscape Conservation and Development Initiative (KSLCDI) a collaborative programme between the Ministry of Forests and Environment, Government of Nepal, Research Centre for Applied Science and Technology (RECAST), Tribhuvan University and International Centre for Integrated Mountain Development (ICIMOD). We are grateful to the Department of National Parks and Wildlife conservation (DNPWC), Ministry of Forests and Soil Conservation, Nepal and Api-Nampa Conservation Area for giving us permission to carry out research. MBR and ZM was supported by the Czech Science Foundation (project 17-10280S) and partly by institutional support RVO 67985939. BT is supported by the National Sustainability Program I (NPU I) (grant number LO1415) of MSMT. We are thankful to Kamal Mohan Ghimire, Santosh Thapa, Khadak Rokaya and local people in Darchula for their help during data collection and Sunil Thapa for preparing the map. Views and interpretations in this publication are those of the authors and are not attributable to funding agencies. Compliance with ethical standards Conflict of interest The authors declare that they have no conflict of interest. Subedi et al. Appendix Table 1 (continued) Appendix Plant species Life form Boehmeria ternifolia D. Don Herb Appendix Table 1 List of plant species recorded in the sampling plots. Plant species Life form Abies spectabilis (D. Don) Mirb. Tree Acer cappadocicum var. indicum (Pax) Rehder Tree Acer pectinatum Wall. ex G.Nicholson Tree Acer sterculiaceum var. tomentosum E. Murray Tree Achyranthes bidentata Blume Herb Aconitum spicatum (Bruhl) Stapf Herb Aconogonum molle var. frondosum (D. Don) H. Hara Herb Aconogonum rumicifolium (Royle ex Bab.) H. Hara Herb Actaeaspicata var. acuminata (Wall. ex Royle) H. Hara Herb Adiantum capillus-veneris L. Herb Aesculus indica (Colebr. ex Cambess.) Hook. Tree Ageratum conyzoides L. Herb Ainsliaea latifolia (D. Don) Sch. Bip. Herb Alnus nepalensis D. Don Tree Amaranthus lividus L. Herb Anaphalis triplinervis var. intermedia (DC.) Airy Shaw Herb Anemone demissa Hook. f. &Thoms Herb Anemone vitifolia Buch.-Ham. ex DC. Herb Anemone tetrasepala Royle Herb Angelica glauca Edgeworth Herb Anisomeles indica (L.) Kuntze Herb Arabidopsis himalaica (Edgew.) O. E. Schulz Herb Arisaema consanguineum Schott Herb Arisaema flavum (Forssk.) Schott Herb Arisaema tortuosum (Wall.) Schott Herb Artemisia dubia Wall. ex Besser Herb Artemisia gmelinii Weber ex Stechm. Herb Asparagus racemosus Willd. Herb Aster diplostephioides (DC.) C. B. Clarke Herb Aster falconeri subsp. nepalensis Grierson Herb Astilbe rivularis Buch.-Ham. ex D. Don Herb Astragalus donianus DC. Herb Berberis aristata var. floribunda (G. Don) Hook. f. & Thomson Berberis asiatica Roxb. ex DC. Shrub Bupleurum falcatum subsp. marginatum (Wall. ex DC.) Herb H. Wolff Buxus wallichiana Baill. Tree Calanthe tricarinata Lindl. Herb Caltha palustris var. himalensis (D. Don) Mukerjee Herb Campanula aristata Wall. Herb Capsella bursa-pastoris (L.) Medik. Herb Cardamine violacea (D. Don) Wall. Herb Cardiocrinum giganteum (Wall.) Makino Herb Carex sp. Herb Cautleya spicata (Sm.) Baker Herb Celtis australis L. Tree Cephalanthera longifolia (L.) Fritsch Herb Chaerophyllum villosum Wall. ex DC. Herb Cheilanthes rufa D. Don Herb Cirsium wallichii var. glabratum (Hook. f.) Wendelbo Herb Clematis connata DC. Herb Clematis montana Buch.-Ham. ex DC. Herb Coleus barbatus (Andrews) Benth. Herb Colocasia fallax Schott Herb Commelina paludosa Blume Herb Corydalis cashmeriana Royle Herb Corydalis juncea Wall. Herb Corylus jacquemontii Decne. Tree Cotoneaster frigidus Wall. ex Lindl. Tree Crotalaria cytisoides Roxb. ex DC. Herb Cuscutaeuropaea var. indica Englem. Herb Cyananthus lobatus Wall. ex Benth. Herb Cyathula tomentosa (Roth) Moq. Shrub Cynoglossum amabile Stapf&Drumm. Herb Cyperus sp. Herb Cypripedium sp. Herb Daphne papyracea Wall. ex Steud. Shrub Delphinium himalayai Munz Herb Desmodium elegans DC. Shrub Deutzia compacta Craib Shrub Shrub Dioscorea deltoidea Wall. ex Griseb. Herb Betula alnoides Buch.-Ham. ex D. Don Tree Dipsacus inermis var. mitis Wall. Herb Betula utilis D. Don Tree Drepanostachyum falcatum (Nees) Keng f. Shrub Bidens pilosa var. minor (Blume) Sherff Herb Dubyaea hispida DC. Herb Bistorta affinis (D. Don) Greene Herb Elaeagnus parvifolia Wall. ex Royle Tree Bistortaamplexicaulis var. amplexicaulis (D. Don) Greene Herb Elatostema sessile J. R. & G. Forst. Herb Elsholtzia fruticosa (D. Don) Rehder Shrub Vascular plant diversity along an elevational gradient in the Central Himalayas, western Nepal Appendix Table 1 (continued) Plant species Appendix Table 1 (continued) Life form Plant species Life form Euonymus fimbriatus Wall. Tree Lonicera quinquelocularis Hardw. Tree Euonymus porphyreusLoes. Tree Lonicera webbiana Wall. ex DC. Shrub Fagopyrum dibotrys (D. Don) H. Hara Herb Lygodium japonicum (Thunberg) Swartz Herb Ficus sarmentosa Buch.-Ham. ex Sm. Shrub Lysimachia ferruginea Edgew. Herb Fragaria nubicola Lindl. ex Lacaita Herb Lysionotus serratus D. Don Herb Fritillaria cirrhosa D. Don Herb Maianthemum purpureum (Wall.) LaFrankie Herb Galium asperuloides subsp. hoffmeisteri (Klotzsch) H. Hara Galium paradoxum Maxim. Herb Meconopsis sp. Herb Microsorum sp. Herb Geranium nepalense Sweet Herb Morina longifolia Wall. ex DC. Herb Geranium pratense L. Herb Girardinia diversifolia (Link) Friis Herb Habenaria pectinata D. Don Halenia elliptica D. Don Herb Myriactis nepalensis Less. Herb Tree Herb Neolitsea pallens (D. Don) Momiy. & H. Hara ex H. Hara Neottia listeroides Lindl. Herb Herb Nepeta erecta (Boyle ex Benth.) Berth. Herb Hedera nepalensis K. Koch Herb Nepeta lamiopsis Benth. ex Hook. f. Herb Hedychium sp. Herb Nephrolepis sp. Herb Hemiphragma heterophyllum Wall. Herb Oxalis corniculata L. Herb Heracleum lallii C. Norman Herb Paeonia emodi Wall. ex Royle Herb Heracleum sp. Herb Parasenecio chenopodifolius (DC.) Grierson Herb Herminium duthiei Hook. f. Herb Paris polyphylla subsp. wallichii Sm. Herb Hippophae salicifolia D. Don Tree Parnassia nubicola Wall. ex Royle Herb Holboellia latifolia Wall. Shrub Parochetus communis Buch.-Ham. ex D. Don Herb Hydrangea anomala D. Don Shrub Pedicularisgracilis Wall. ex Benth. Herb Hydrangea heteromalla D. Don Tree Pedicularis klotzschii Hurus. Herb Ilex dipyrena Wall. Tree Persicaria capitata (Buch.-Ham. ex D. Don) H. Gross Herb Impatiens bicornuta var. bicornuta Wall. Herb Philadelphus tomentosus f. nepalensis Wall. ex G. Don Shrub Impatiens sulcata Wall. Herb Phlomis bracteosa Royle ex Benth. Herb Impatiens urticifolia Wall. Herb Pilea racemosa (Royle) Tuyama Herb Imperata sp. Herb Pilea umbrosa Blume Herb Indigofera bracteata Graham ex Baker Shrub Piptanthus nepalensis (Hook.) D. Don Shrub Jasminum dispermum Wall. Shrub Pleurospermum angelicoides (DC.) C. B. Clarke Herb Jasminum humile L. Shrub Podophyllum hexandrum Royle Herb Juglans regia L. Tree Polygonatum cirrhifolium (Wall.) Royle Herb Juncus sp. Herb Polygonatum verticillatum (L.) All. Herb Lamium album L. Herb Herb Lepisorus sp. Herb Polystichum prescottianum (Wallich ex Mettenius) T. Moore Potentilla argyrophylla var. atrosanguinea Wall. ex Lehm. Potentilla cuneata Wall. ex Lehm. Leucas lanata Benth. Herb Prenanthes brunoniana Wall. ex DC. Herb Leucosceptrum canum Sm. Shrub Primula involucrata Wall. ex Duby Herb Leycesteria formosa Wall. Shrub Prinsepia utilis Royle Shrub Ligularia amplexicaulis DC. Herb Prunus cornuta (Wall. ex Royle) Steud. Tree Lilium nanum Klotzsch Herb Prunus napaulensis (Ser.) Steud. Tree Lilium nepalense D. Don Herb Pyracantha crenulata (D. Don) M. Roem. Shrub Lathyrus laevigatus subsp. emodi (Waldst. & Kit.) Gren. Herb Lecanthus peduncularis (Royle) Wedd. Herb Herb Herb Subedi et al. Appendix Table 1 (continued) Plant species Appendix Table 1 (continued) Life form Plant species Quercus semecarpifolia Sm. Tree Swertia ciliata (D. Don ex G. Don) B. L. Burtt Herb Ranunculus diffusus DC. Herb Swertia petiolata D. Don Herb Rheum australe D. Don Herb Syringa emodi Wall. ex Royle Shrub Rhodiola chrysanthemifolia (H. Léveillé) S. H. Fu Herb Taxus contorta Griff. Tree Rhododendron arboreum Sm. Tree Tetrastigma serrulatum (Roxb.) Planch. Herb Rhododendron barbatum Wall. ex G. Don Tree Thalictrum cultratum Wall. Herb Rhododendron campanulatum D. Don Shrub Thalictrum foliolosum DC. Herb Rhus wallichii Hook. f. Tree Thelypteris erubescens (Wall. ex Hook.) Ching Herb Ribes glaciale Wall. Shrub Toona serrata (Royle) M. Roem Tree Ribes luridum Hook. f. & Thomson Shrub Trifolium repens L. Herb Rosa macrophylla Lindl. Shrub Trigonella emodii Benth. Herb Rosa sericea Lindl. Shrub Tsuga dumosa (D. Don) Eichler Tree Rubia manjith Roxb. ex Fleming Herb Ulmus wallichiana Planch. Tree Rubia wallichiana Decne. Herb Urtica ardens Link Herb Rubus biflorus Buch.-Ham. ex Sm. Shrub Valeriana hardwickii Wall. Herb Rubus calycinus Wall. ex D. Don Herb Veronica cana Wall. ex Benth. Herb Rumex acetosa L. Herb Viburnum cotinifolium D. Don Shrub Salix hylematica C. K. Schneid. Shrub Viburnum erubescens Wall. ex DC. Tree Salix tetrasperma var. pyrina Roxb. Tree Viburnum mullaha Buch.-Ham. ex D. Don Shrub Sarcococca saligna (D. Don) Mull. Arg. Shrub Viola biflora L. Herb Saurauia napaulensis DC. Tree Vitis parvifolia Roxb. Shrub Saussurea fastuosa (Decne.) Sch. Bip. Herb Saxifraga parnassifolia D. Don Herb Saxifraga sp. Herb Scurrula elata (Edgew.) Danser Shrub Scutellaria prostrata Jacq. ex Benth. Herb Sedum multicaule Wallich ex Lindley Herb Selaginella sp. Herb Selinum wallichianum (DC.) Raizada & Saxena Herb Senecio chrysanthemoides DC. Herb Silene stracheyi Edgew. Herb Smilax aspera L. Shrub Solena heterophylla Lour. Herb Sorbus lanata (D. Don) Schauer Tree Sorbus microphylla Wenz. Tree Spiraea bella Sims Shrub Stachys melissaefolia Benth. Herb Stellaria media Vill. Herb Stellaria monosperma f. paniculata (Edgew.) Majumdar Stephania glabra (Roxb.) Miers Herb Herb Strobilanthes attenuata subsp. nepalensis J. R. I. Wood Shrub Strobilanthes tomentosa (Nees) J. R. I. Wood Herb Swertia chirayita (Roxb. ex Fleming) Karsten Herb Life form References Abella SR, Springer JD (2015) Effects of tree cutting and fire on understory vegetation in mixed conifer forests. 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