Epiphytic species are ecologically important and a significant component of biodiversity. To ensu... more Epiphytic species are ecologically important and a significant component of biodiversity. To ensure their efficient conservation, we need to understand their ecology and host plant associations. It is also important to investigate how the predicted temperature change will affect their future distribution. Here, we use data collected in Nepal to investigate how epiphytic orchids are associated with host species, their distribution patterns, and how they may be threatened by the predicted increase in temperature towards the end of the 21st century. We used the phi coefficient (Φ) of association to calculate the associations of epiphytic orchid species with plants and rarefaction to describe the diversity of orchids associated with a particular host species. We used interpolation to estimate the distribution of epiphytic orchids and their host species along altitudinal gradients. The phi (Φ) coefficient of association revealed that 30 species of host plants showed more association with different orchid species than expected. The number of epiphytic orchids increased with the number of host individuals. We predict that an increase in temperature by ~3 • C, which is a more moderate value of temperature increase by the end of the 21st century, will affect at least 52 narrow-ranged species of orchids and 58 narrow-ranged species of host plants. Therefore, we should make efforts to prevent many plant species from becoming extinct, as an increase in temperature is likely to affect their existence.
Ethnopharmacological relevance: Gastrointestinal disorders cause morbidity and can lead to mortal... more Ethnopharmacological relevance: Gastrointestinal disorders cause morbidity and can lead to mortality, especially in the developing world where sanitation is deficient. A large part of the human population relies on medicinal plants for treating various diseases, including gastrointestinal disorders. The present review summarizes the traditional uses of medicinal plants of Nepal used to treat gastrointestinal disorders, and evaluates their bio-efficacy based on a review of the available phytochemical and pharmacological literature. Material and methods: We searched different electronic databases and libraries for the literature on medicinal plants used in Nepal to treat gastrointestinal disorders. For each species, we also searched the literature for information on conservation status, as well as for phytochemical and pharmacological studies in support of the ethnobotanical information. We used principal component analysis to explore the relation among disorders and plant families, plant life forms, plant parts and preparation modes. We also performed permutation tests to determine if botanical families were used more often than expected considering their availability in the Nepali flora. Results: We documented a total of 947 species belonging to 158 families and 586 genera used to treat gastrointestinal disorders in Nepal. Diarrhea was the disorder treated by the highest number of species (348), followed by stomachache (340) and dysentery (307). Among the reported species, five were endemic to Nepal, whereas 16 orchid species were protected under CITES Appendices II and III. The randomization test showed that species belonging to 14 families were used less often than expected, whereas plants belonging to 25 families were used more often than expected. The PCA scatter plot showed distinct groups of gastrointestinal disorders treated with similar plant life forms, plant parts, and/or preparation modes. We found 763 phytochemical studies on 324 species and 654 pharmacological studies on 269 species. Conclusion: We showed the diversity and importance of medicinal plants used to treat gastrointestinal disorders in the traditional health care system of Nepal. As such disorders are still causing several deaths each year, it is of the utmost importance to conduct phytochemical and pharmacological studies on the most promising species. It is also crucial to increase access to traditional medicine, especially in rural areas. Threatened species need special attention for traditional herbal medicine to be exploited sustainably.
Chir pine (Pinus roxburghii) and blue pine (P. wallichiana) are two dominant tree species in the ... more Chir pine (Pinus roxburghii) and blue pine (P. wallichiana) are two dominant tree species in the mid-hill forests of Nepal that also contribute significantly to the country’s total forest area. The associated vegetation pattern in pine forests is influenced by environmental and edaphic factors. The objective of this study was to determine the correlation between soil chemical properties and the composition of associated plant species of two pine forests in the Kailash Sacred Landscape, Nepal. We used the quadrat sampling method to collect vegetation and soil data. Pearson’s correlation was used to determine the relationship between soil chemical properties. Generalized Linear model (GLM) to assess the effect of soil properties on species richness, and Canonical Correlation Analysis (CCA) for species composition. Our analysis showed that soil pH was negatively correlated with soil chemical properties and species richness of associated species. There was a high number of associated pl...
In total, 118 orchid species (25%) are endemic to the Himalayan region and 21 species are endemic... more In total, 118 orchid species (25%) are endemic to the Himalayan region and 21 species are endemic to Nepal. Krober’s percentage similarity showed that the EAFR and ICFR have the highest percentage similarity (87%) followed by the MFR and ICFR (62%). In total, 92 species were used for medicinal purposes and 6 as food plants in Nepal. We conclude that Nepal is rich in orchid flora and the highest percentage of orchids originates from the EAFR
Epiphytic orchids are common in subtropical forests, but little is known about the factors that d... more Epiphytic orchids are common in subtropical forests, but little is known about the factors that determine their diversity. We surveyed two sites (north-facing Phulchowki and south-facing Shivapuri hills), in the sub-tropical forest in the Kathmandu valley, central Nepal. Along five transects per site, spanning an altitudinal gradient of 1525–2606 m a.s.l., we recorded all epiphytic orchids and the host species on which they were growing. The data were analyzed using a generalized linear model (GLM) and redundancy analysis (RDA). Species richness significantly decreased with increasing altitude and was higher in larger hosts and in places with high temperature. Species composition was affected by altitude, distance from the forest edge, host type, and precipitation. This study indicates that the most important factors affecting epiphytic orchid diversity was altitude, even if other factors were associated with patterns in composition. The low-altitude habitats with high species diver...
Factors determining the spatial distribution of bird species along altitudinal gradients have bee... more Factors determining the spatial distribution of bird species along altitudinal gradients have been important in their ecological and biogeographical research. Here, have used the data on bird species recorded in Manang, central Nepal Himalayas and attempt to determine the drivers of bird species diversity. We also carried out indicator species analysis to observe if any bird species are associated with different altitudinal ranges and land use gradients. We recorded 1331 individuals belonging to 82 species of both resident and itinerant birds. In our study, altitude was the major factor determining species richness and abundance. Position of study localities is main factor determining bird community composition. Diversity of bird species were mainly found in habitats that were far human settlements, having high annual mean temperature and more roughness. Species diversity was high during July-August compared to September-October and in north-facing slopes, and also in shrub and tree covered areas than grassland and places with mostly snow and grassland. Indicator species analysis showed only 21 species were significantly associated with altitudinal gradients, mostly below 3000 m a.s.l. and only eight bird species were associated with two land use gradients (grassland and snow-glacier). In conclusion, position of sampled localities, altitude, aspect, land use types and different climatic factors were important determinants of bird diversity along altitudinal gradients in Manang. To protect bird diversity in Manang, we need to protect habitats that are located mainly in low altitudes for most of the bird species. However, high altitude habitats with snow and glaciers are also important for few bird species. Thus, a large area with heterogenous habitats is important for bird species management and conservation.
Studies on population dynamics are helpful for understanding the factors determining population d... more Studies on population dynamics are helpful for understanding the factors determining population development and predicting the effects of disturbances, such as harvesting of plant species. In an investigation of the demography of a terrestrial medicinal orchid known as Crepidium acuminatum, the effects of harvesting on its population dynamics were recorded. Data on recruitment, growth and survival were collected in three populations of C. acuminatum over a 6-year period (2012–2017) in central Nepal. A matrix modeling method was used to determine the effect of different harvesting regimes on the population growth and survival of this species. Population growth rates (λ) of unharvested populations were relatively similar and stable in different years of the study. Harvesting significantly reduced λ. The results of this study indicate that the sustainable survival of a population that is subject to harvesting can only occur when it is either selective (only flowering individuals or onl...
Elevational gradients are linked with different abiotic and biotic factors, which in turn influen... more 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 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.
Butterflies are widely studied due to their key ecosystem functions. For this reason, they are us... more Butterflies are widely studied due to their key ecosystem functions. For this reason, they are used in ecosystem assessment, formulating conservation plans and in raising the environmental awareness. Quantification of different factors affecting diversity of butterflies is important for their effective conservation. In this study, we investigated abiotic and biotic factors affecting species richness and community composition of butterflies along an elevational gradient in Manang region, central Nepal. We also tested if butterfly species follow the Bergmann’s rule. A total of 57 butterfly species belonging to 39 genera and 8 families were recorded in the study area. Out of a total of 127 plant species identified in the study region, only 67 plant species were visited by butterflies as nectar sources. Species richness of butterflies increased with increasing elevation. Species richness was significantly higher in places with shrubs compared to other places and also in autumn than in summer. Species richness of butterflies also depended on composition of plant species occurring at the localities. Butterfly species composition varied among sampling localities. It was also determined by habitat type, elevation, sampling time, plant species and interactions of elevation × time. The relationship between butterfly size and elevation was in the opposite direction than expected according to the Bergmann’s rule. In conclusion, protection of butterfly diversity can only be achieved by protecting different habitats across the diverse physiography of the region and different plant species, in particular herbs and shrubs. Our results do not support the Bergmann’s rule for butterflies along an elevational gradient in our region.
ETHNOPHARMACOLOGICAL RELEVANCE Neopicrorhiza scrophulariiflora (Pennell) Hong is important medici... more ETHNOPHARMACOLOGICAL RELEVANCE Neopicrorhiza scrophulariiflora (Pennell) Hong is important medicinal plant that is native to the eastern Himalayas and Hengduan mountains in China. It is also distributed in Nepal, north east India, Bhutan and northern Myanmar. Plant parts are traditionally used against different kinds of diseases and various compounds present in different plant parts are also effective against many diseases. Thus, N. scrophulariiflora has a high potential to maintain human health. AIM OF THE REVIEW Although N. scrophulariiflora is very important and widely studied plant species but there is no comprehensive up-to-date review of published and unpublished literature. So, in the present article we have compiled and critically commented on the botanical characteristics, traditional uses, plant growth and cultivation, micropropagation, conservation status, secondary metabolites, pharmacology and toxicity of the plant. MATERIALS AND METHODS Extensive literature searches both electronic online databases (Google Scholar, Scopus, Springer Link, Web of Science, ScienceDirect, ResearchGate, PubMed, ChemSpider, USPTO, Google patents and Espacenet) and library visits in Nepal were carried out to collect the literature on information published prior to April 2019. RESULTS N. scrophulariiflora was traditionally used for 82 ailments/diseases. There are 124 major phytochemicals extracted from the plant. Several compounds are effective in bioactivity. Pharmacologically, the plant is proved to be anti-atherosclerotic, antidiabetic and anti-inflammatory in-vivo studies, and antimicrobial, antimalarial, antioxidative, hepatoprotective, immunomodulatory and nerve growth factor potentiating from in-vitro studies. Renal improvement activities were confirmed from both in-vivo and in-vitro studies. Toxicological tests and a single clinical trial in human beings have supported the notion that the plant is not poisonous but beneficial for curing wide ranges of diseases. CONCLUSION N. scrophulariiflora is valuable medicinal plant that can serve as promising source of non-harmful and potential medicinal herbal remedies for human beings.
The medicinal plant D. Don was collected in Rasuwa District (Nepal) and the xanthone content of i... more The medicinal plant D. Don was collected in Rasuwa District (Nepal) and the xanthone content of its ethyl acetate extracts was studied. The total amount of xanthones in determined by HPLC reaches almost 13 g of xanthones per 1 kg of dry matter. The identification of xanthones in was achieved by a combination of HPLC, LC⁻MS and LC⁻NMR. The final assignment of the individual chemical structures was provided by NMR, supported by preparative HPLC. In eight chromatographic peaks, four major xanthones were identified—1,3-dihydroxy-5,8-dimethoxyxanthone, 1-hydroxy-3,5,8-trimethoxyxanthone, bellidifolin (1,5,8-tri-hydroxy-3-methoxyxanthone), and decussatin (1-hydroxy-3,7,8-trimethoxyxanthone).
Associations between epiphytes and their hosts are among the main factors affecting the biodivers... more Associations between epiphytes and their hosts are among the main factors affecting the biodiversity and distribution of epiphytes. While several previous studies explored the association between epiphyte diversity and host characteristics, very little is known about the generality of such associations at larger spatial scales. We aim to explore the associations between diversity and distribution of epiphytic orchids and host characteristics in different localities in Nepal. Epiphytic orchids and their hosts were recorded along the transects in total of 23,539 host individuals. To describe the diversity of orchids in the different localities, a rarefaction function was used. Univariate and multivariate analyses were carried out to explore the associations with locality, host characteristics, and their interactions with locality. In total, we recorded 141 species of orchids growing on 192 host species. The five localities significantly differed in orchid diversity and abundance. The number of orchid individuals per host species significantly increased with increasing number of host individuals. Species richness, abundances, occupancy of orchid species on host species and composition of orchids varied across the localities. Species richness and abundance was significantly higher on hosts in the higher strata and differed between families of host species. Abundance was higher on evergreen hosts. Composition of orchid communities are also associated with host characteristics, such as habit (shrub/tree/climber), bark texture, nature (deciduous/evergreen) and the plant families of host species. This study revealed a high diversity of epiphytic orchids in the localities studied and strong associations between the orchids and their hosts. Future studies looking at the relationships between epiphyte communities and host characteristics need to identify relationships at a wider scale in order to determine whether they are really general rather than site-specific.
Ethnopharmacological relevance: Gastrointestinal disorders cause morbidity and can lead to mortal... more Ethnopharmacological relevance: Gastrointestinal disorders cause morbidity and can lead to mortality, especially in the developing world where sanitation is deficient. A large part of the human population relies on medicinal plants for treating various diseases, including gastrointestinal disorders. The present review summarizes the traditional uses of medicinal plants of Nepal used to treat gastrointestinal disorders, and evaluates their bio-efficacy based on a review of the available phytochemical and pharmacological literature. Material and methods: We searched different electronic databases and libraries for the literature on medicinal plants used in Nepal to treat gastrointestinal disorders. For each species, we also searched the literature for information on conservation status, as well as for phytochemical and pharmacological studies in support of the ethnobotanical information. We used principal component analysis to explore the relation among disorders and plant families, plant life forms, plant parts and preparation modes. We also performed permutation tests to determine if botanical families were used more often than expected considering their availability in the Nepali flora. Results: We documented a total of 947 species belonging to 158 families and 586 genera used to treat gastrointestinal disorders in Nepal. Diarrhea was the disorder treated by the highest number of species (348), followed by stomachache (340) and dysentery (307). Among the reported species, five were endemic to Nepal, whereas 16 orchid species were protected under CITES Appendices II and III. The randomization test showed that species belonging to 14 families were used less often than expected, whereas plants belonging to 25 families were used more often than expected. The PCA scatter plot showed distinct groups of gastrointestinal disorders treated with similar plant life forms, plant parts, and/or preparation modes. We found 763 phytochemical studies on 324 species and 654 pharmacological studies on 269 species. Conclusion: We showed the diversity and importance of medicinal plants used to treat gastrointestinal disorders in the traditional health care system of Nepal. As such disorders are still causing several deaths each year, it is of the utmost importance to conduct phytochemical and pharmacological studies on the most promising species. It is also crucial to increase access to traditional medicine, especially in rural areas. Threatened species need special attention for traditional herbal medicine to be exploited sustainably.
This study aimed to compare the distribution patterns and trends of plant parts used among differ... more This study aimed to compare the distribution patterns and trends of plant parts used among different groups of medicinal plants, geographical regions, and between medicinal plants and all vascular plants. We used the published sources for elevation records of 2,331 medicinal plant species to interpolate presence between minimum and maximum elevations and estimated medicinal plant richness for each 100-m elevational band. Monte Carlo simulations were used to test whether differences in elevational distribution between different groups of medicinal plants were significant. Total number of medicinal plants as well as different groups showed unimodal relationship with elevation. The elevational distributions of medicinal plants significantly differ between regions and between medicinal plant groups. When comparing the richness of all medicinal plants to all vascular plants, Monte Carlo simulations indicated that the numbers of medicinal plants are higher than expected at low elevations. The highest richness of medicinal plants at low elevation could be possibly due to favorable environmental factors such as high temperature, rainfall, sunlight or due to higher density of human population and thus higher pressure on use of any plants in lower elevations.
Ethnopharmacological relevance: Rheum australe D. Don (Polygonaceae) has been commonly used in tr... more Ethnopharmacological relevance: Rheum australe D. Don (Polygonaceae) has been commonly used in traditional medicine for a wide range of ailments related to the circulatory, digestive, endocrine, respiratory and skeletal systems as well as to infectious diseases. Aim of the review: To provide the up-to-date information that is available on the botany, traditional uses, phytochemistry, pharmacology and toxicology of Rheum australe. Additionally, to highlight the possible uses of this species to treat different diseases and to provide a basis for future research. Materials and methods: The present review covers the literature available from 1980 to 2011. The information was collected from scientific journals, books, theses and reports via a library and electronic search (Google Scholar, Web of Science and ScienceDirect). Results: Ethnomedical uses of Rheum australe have been recorded from China, India, Nepal and Pakistan for 57 different types of ailments. The phytochemical studies have shown the presence of many secondary metabolites belonging to anthraquinones, stilbenes, anthrones, oxantrone ethers and esters, chromones, flavonoids, carbohydrate, lignans, phenols and sterols. Crude extracts and isolated compounds from Rheum australe show a wide spectrum of pharmacological activities, such as antidiabetic, anti-inflammatory, antifungal, antimicrobial, antioxidant, anticancer, hepatoprotective and immuneenhancing activities, as well as a usefulness for improving renal function. Conclusion: Rheum australe has been widely used source of medicine for years without any adverse effects. Many studies have provided evidence for various traditional uses. However, there is a need for additional studies of the isolated compounds to validate the traditional uses in human models. The present review on the botany, traditional uses, phytochemistry and toxicity has provided preliminary information for further studies and commercial exploitations of the plant.
Epiphytic species are ecologically important and a significant component of biodiversity. To ensu... more Epiphytic species are ecologically important and a significant component of biodiversity. To ensure their efficient conservation, we need to understand their ecology and host plant associations. It is also important to investigate how the predicted temperature change will affect their future distribution. Here, we use data collected in Nepal to investigate how epiphytic orchids are associated with host species, their distribution patterns, and how they may be threatened by the predicted increase in temperature towards the end of the 21st century. We used the phi coefficient (Φ) of association to calculate the associations of epiphytic orchid species with plants and rarefaction to describe the diversity of orchids associated with a particular host species. We used interpolation to estimate the distribution of epiphytic orchids and their host species along altitudinal gradients. The phi (Φ) coefficient of association revealed that 30 species of host plants showed more association with different orchid species than expected. The number of epiphytic orchids increased with the number of host individuals. We predict that an increase in temperature by ~3 • C, which is a more moderate value of temperature increase by the end of the 21st century, will affect at least 52 narrow-ranged species of orchids and 58 narrow-ranged species of host plants. Therefore, we should make efforts to prevent many plant species from becoming extinct, as an increase in temperature is likely to affect their existence.
Ethnopharmacological relevance: Gastrointestinal disorders cause morbidity and can lead to mortal... more Ethnopharmacological relevance: Gastrointestinal disorders cause morbidity and can lead to mortality, especially in the developing world where sanitation is deficient. A large part of the human population relies on medicinal plants for treating various diseases, including gastrointestinal disorders. The present review summarizes the traditional uses of medicinal plants of Nepal used to treat gastrointestinal disorders, and evaluates their bio-efficacy based on a review of the available phytochemical and pharmacological literature. Material and methods: We searched different electronic databases and libraries for the literature on medicinal plants used in Nepal to treat gastrointestinal disorders. For each species, we also searched the literature for information on conservation status, as well as for phytochemical and pharmacological studies in support of the ethnobotanical information. We used principal component analysis to explore the relation among disorders and plant families, plant life forms, plant parts and preparation modes. We also performed permutation tests to determine if botanical families were used more often than expected considering their availability in the Nepali flora. Results: We documented a total of 947 species belonging to 158 families and 586 genera used to treat gastrointestinal disorders in Nepal. Diarrhea was the disorder treated by the highest number of species (348), followed by stomachache (340) and dysentery (307). Among the reported species, five were endemic to Nepal, whereas 16 orchid species were protected under CITES Appendices II and III. The randomization test showed that species belonging to 14 families were used less often than expected, whereas plants belonging to 25 families were used more often than expected. The PCA scatter plot showed distinct groups of gastrointestinal disorders treated with similar plant life forms, plant parts, and/or preparation modes. We found 763 phytochemical studies on 324 species and 654 pharmacological studies on 269 species. Conclusion: We showed the diversity and importance of medicinal plants used to treat gastrointestinal disorders in the traditional health care system of Nepal. As such disorders are still causing several deaths each year, it is of the utmost importance to conduct phytochemical and pharmacological studies on the most promising species. It is also crucial to increase access to traditional medicine, especially in rural areas. Threatened species need special attention for traditional herbal medicine to be exploited sustainably.
Chir pine (Pinus roxburghii) and blue pine (P. wallichiana) are two dominant tree species in the ... more Chir pine (Pinus roxburghii) and blue pine (P. wallichiana) are two dominant tree species in the mid-hill forests of Nepal that also contribute significantly to the country’s total forest area. The associated vegetation pattern in pine forests is influenced by environmental and edaphic factors. The objective of this study was to determine the correlation between soil chemical properties and the composition of associated plant species of two pine forests in the Kailash Sacred Landscape, Nepal. We used the quadrat sampling method to collect vegetation and soil data. Pearson’s correlation was used to determine the relationship between soil chemical properties. Generalized Linear model (GLM) to assess the effect of soil properties on species richness, and Canonical Correlation Analysis (CCA) for species composition. Our analysis showed that soil pH was negatively correlated with soil chemical properties and species richness of associated species. There was a high number of associated pl...
In total, 118 orchid species (25%) are endemic to the Himalayan region and 21 species are endemic... more In total, 118 orchid species (25%) are endemic to the Himalayan region and 21 species are endemic to Nepal. Krober’s percentage similarity showed that the EAFR and ICFR have the highest percentage similarity (87%) followed by the MFR and ICFR (62%). In total, 92 species were used for medicinal purposes and 6 as food plants in Nepal. We conclude that Nepal is rich in orchid flora and the highest percentage of orchids originates from the EAFR
Epiphytic orchids are common in subtropical forests, but little is known about the factors that d... more Epiphytic orchids are common in subtropical forests, but little is known about the factors that determine their diversity. We surveyed two sites (north-facing Phulchowki and south-facing Shivapuri hills), in the sub-tropical forest in the Kathmandu valley, central Nepal. Along five transects per site, spanning an altitudinal gradient of 1525–2606 m a.s.l., we recorded all epiphytic orchids and the host species on which they were growing. The data were analyzed using a generalized linear model (GLM) and redundancy analysis (RDA). Species richness significantly decreased with increasing altitude and was higher in larger hosts and in places with high temperature. Species composition was affected by altitude, distance from the forest edge, host type, and precipitation. This study indicates that the most important factors affecting epiphytic orchid diversity was altitude, even if other factors were associated with patterns in composition. The low-altitude habitats with high species diver...
Factors determining the spatial distribution of bird species along altitudinal gradients have bee... more Factors determining the spatial distribution of bird species along altitudinal gradients have been important in their ecological and biogeographical research. Here, have used the data on bird species recorded in Manang, central Nepal Himalayas and attempt to determine the drivers of bird species diversity. We also carried out indicator species analysis to observe if any bird species are associated with different altitudinal ranges and land use gradients. We recorded 1331 individuals belonging to 82 species of both resident and itinerant birds. In our study, altitude was the major factor determining species richness and abundance. Position of study localities is main factor determining bird community composition. Diversity of bird species were mainly found in habitats that were far human settlements, having high annual mean temperature and more roughness. Species diversity was high during July-August compared to September-October and in north-facing slopes, and also in shrub and tree covered areas than grassland and places with mostly snow and grassland. Indicator species analysis showed only 21 species were significantly associated with altitudinal gradients, mostly below 3000 m a.s.l. and only eight bird species were associated with two land use gradients (grassland and snow-glacier). In conclusion, position of sampled localities, altitude, aspect, land use types and different climatic factors were important determinants of bird diversity along altitudinal gradients in Manang. To protect bird diversity in Manang, we need to protect habitats that are located mainly in low altitudes for most of the bird species. However, high altitude habitats with snow and glaciers are also important for few bird species. Thus, a large area with heterogenous habitats is important for bird species management and conservation.
Studies on population dynamics are helpful for understanding the factors determining population d... more Studies on population dynamics are helpful for understanding the factors determining population development and predicting the effects of disturbances, such as harvesting of plant species. In an investigation of the demography of a terrestrial medicinal orchid known as Crepidium acuminatum, the effects of harvesting on its population dynamics were recorded. Data on recruitment, growth and survival were collected in three populations of C. acuminatum over a 6-year period (2012–2017) in central Nepal. A matrix modeling method was used to determine the effect of different harvesting regimes on the population growth and survival of this species. Population growth rates (λ) of unharvested populations were relatively similar and stable in different years of the study. Harvesting significantly reduced λ. The results of this study indicate that the sustainable survival of a population that is subject to harvesting can only occur when it is either selective (only flowering individuals or onl...
Elevational gradients are linked with different abiotic and biotic factors, which in turn influen... more 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 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.
Butterflies are widely studied due to their key ecosystem functions. For this reason, they are us... more Butterflies are widely studied due to their key ecosystem functions. For this reason, they are used in ecosystem assessment, formulating conservation plans and in raising the environmental awareness. Quantification of different factors affecting diversity of butterflies is important for their effective conservation. In this study, we investigated abiotic and biotic factors affecting species richness and community composition of butterflies along an elevational gradient in Manang region, central Nepal. We also tested if butterfly species follow the Bergmann’s rule. A total of 57 butterfly species belonging to 39 genera and 8 families were recorded in the study area. Out of a total of 127 plant species identified in the study region, only 67 plant species were visited by butterflies as nectar sources. Species richness of butterflies increased with increasing elevation. Species richness was significantly higher in places with shrubs compared to other places and also in autumn than in summer. Species richness of butterflies also depended on composition of plant species occurring at the localities. Butterfly species composition varied among sampling localities. It was also determined by habitat type, elevation, sampling time, plant species and interactions of elevation × time. The relationship between butterfly size and elevation was in the opposite direction than expected according to the Bergmann’s rule. In conclusion, protection of butterfly diversity can only be achieved by protecting different habitats across the diverse physiography of the region and different plant species, in particular herbs and shrubs. Our results do not support the Bergmann’s rule for butterflies along an elevational gradient in our region.
ETHNOPHARMACOLOGICAL RELEVANCE Neopicrorhiza scrophulariiflora (Pennell) Hong is important medici... more ETHNOPHARMACOLOGICAL RELEVANCE Neopicrorhiza scrophulariiflora (Pennell) Hong is important medicinal plant that is native to the eastern Himalayas and Hengduan mountains in China. It is also distributed in Nepal, north east India, Bhutan and northern Myanmar. Plant parts are traditionally used against different kinds of diseases and various compounds present in different plant parts are also effective against many diseases. Thus, N. scrophulariiflora has a high potential to maintain human health. AIM OF THE REVIEW Although N. scrophulariiflora is very important and widely studied plant species but there is no comprehensive up-to-date review of published and unpublished literature. So, in the present article we have compiled and critically commented on the botanical characteristics, traditional uses, plant growth and cultivation, micropropagation, conservation status, secondary metabolites, pharmacology and toxicity of the plant. MATERIALS AND METHODS Extensive literature searches both electronic online databases (Google Scholar, Scopus, Springer Link, Web of Science, ScienceDirect, ResearchGate, PubMed, ChemSpider, USPTO, Google patents and Espacenet) and library visits in Nepal were carried out to collect the literature on information published prior to April 2019. RESULTS N. scrophulariiflora was traditionally used for 82 ailments/diseases. There are 124 major phytochemicals extracted from the plant. Several compounds are effective in bioactivity. Pharmacologically, the plant is proved to be anti-atherosclerotic, antidiabetic and anti-inflammatory in-vivo studies, and antimicrobial, antimalarial, antioxidative, hepatoprotective, immunomodulatory and nerve growth factor potentiating from in-vitro studies. Renal improvement activities were confirmed from both in-vivo and in-vitro studies. Toxicological tests and a single clinical trial in human beings have supported the notion that the plant is not poisonous but beneficial for curing wide ranges of diseases. CONCLUSION N. scrophulariiflora is valuable medicinal plant that can serve as promising source of non-harmful and potential medicinal herbal remedies for human beings.
The medicinal plant D. Don was collected in Rasuwa District (Nepal) and the xanthone content of i... more The medicinal plant D. Don was collected in Rasuwa District (Nepal) and the xanthone content of its ethyl acetate extracts was studied. The total amount of xanthones in determined by HPLC reaches almost 13 g of xanthones per 1 kg of dry matter. The identification of xanthones in was achieved by a combination of HPLC, LC⁻MS and LC⁻NMR. The final assignment of the individual chemical structures was provided by NMR, supported by preparative HPLC. In eight chromatographic peaks, four major xanthones were identified—1,3-dihydroxy-5,8-dimethoxyxanthone, 1-hydroxy-3,5,8-trimethoxyxanthone, bellidifolin (1,5,8-tri-hydroxy-3-methoxyxanthone), and decussatin (1-hydroxy-3,7,8-trimethoxyxanthone).
Associations between epiphytes and their hosts are among the main factors affecting the biodivers... more Associations between epiphytes and their hosts are among the main factors affecting the biodiversity and distribution of epiphytes. While several previous studies explored the association between epiphyte diversity and host characteristics, very little is known about the generality of such associations at larger spatial scales. We aim to explore the associations between diversity and distribution of epiphytic orchids and host characteristics in different localities in Nepal. Epiphytic orchids and their hosts were recorded along the transects in total of 23,539 host individuals. To describe the diversity of orchids in the different localities, a rarefaction function was used. Univariate and multivariate analyses were carried out to explore the associations with locality, host characteristics, and their interactions with locality. In total, we recorded 141 species of orchids growing on 192 host species. The five localities significantly differed in orchid diversity and abundance. The number of orchid individuals per host species significantly increased with increasing number of host individuals. Species richness, abundances, occupancy of orchid species on host species and composition of orchids varied across the localities. Species richness and abundance was significantly higher on hosts in the higher strata and differed between families of host species. Abundance was higher on evergreen hosts. Composition of orchid communities are also associated with host characteristics, such as habit (shrub/tree/climber), bark texture, nature (deciduous/evergreen) and the plant families of host species. This study revealed a high diversity of epiphytic orchids in the localities studied and strong associations between the orchids and their hosts. Future studies looking at the relationships between epiphyte communities and host characteristics need to identify relationships at a wider scale in order to determine whether they are really general rather than site-specific.
Ethnopharmacological relevance: Gastrointestinal disorders cause morbidity and can lead to mortal... more Ethnopharmacological relevance: Gastrointestinal disorders cause morbidity and can lead to mortality, especially in the developing world where sanitation is deficient. A large part of the human population relies on medicinal plants for treating various diseases, including gastrointestinal disorders. The present review summarizes the traditional uses of medicinal plants of Nepal used to treat gastrointestinal disorders, and evaluates their bio-efficacy based on a review of the available phytochemical and pharmacological literature. Material and methods: We searched different electronic databases and libraries for the literature on medicinal plants used in Nepal to treat gastrointestinal disorders. For each species, we also searched the literature for information on conservation status, as well as for phytochemical and pharmacological studies in support of the ethnobotanical information. We used principal component analysis to explore the relation among disorders and plant families, plant life forms, plant parts and preparation modes. We also performed permutation tests to determine if botanical families were used more often than expected considering their availability in the Nepali flora. Results: We documented a total of 947 species belonging to 158 families and 586 genera used to treat gastrointestinal disorders in Nepal. Diarrhea was the disorder treated by the highest number of species (348), followed by stomachache (340) and dysentery (307). Among the reported species, five were endemic to Nepal, whereas 16 orchid species were protected under CITES Appendices II and III. The randomization test showed that species belonging to 14 families were used less often than expected, whereas plants belonging to 25 families were used more often than expected. The PCA scatter plot showed distinct groups of gastrointestinal disorders treated with similar plant life forms, plant parts, and/or preparation modes. We found 763 phytochemical studies on 324 species and 654 pharmacological studies on 269 species. Conclusion: We showed the diversity and importance of medicinal plants used to treat gastrointestinal disorders in the traditional health care system of Nepal. As such disorders are still causing several deaths each year, it is of the utmost importance to conduct phytochemical and pharmacological studies on the most promising species. It is also crucial to increase access to traditional medicine, especially in rural areas. Threatened species need special attention for traditional herbal medicine to be exploited sustainably.
This study aimed to compare the distribution patterns and trends of plant parts used among differ... more This study aimed to compare the distribution patterns and trends of plant parts used among different groups of medicinal plants, geographical regions, and between medicinal plants and all vascular plants. We used the published sources for elevation records of 2,331 medicinal plant species to interpolate presence between minimum and maximum elevations and estimated medicinal plant richness for each 100-m elevational band. Monte Carlo simulations were used to test whether differences in elevational distribution between different groups of medicinal plants were significant. Total number of medicinal plants as well as different groups showed unimodal relationship with elevation. The elevational distributions of medicinal plants significantly differ between regions and between medicinal plant groups. When comparing the richness of all medicinal plants to all vascular plants, Monte Carlo simulations indicated that the numbers of medicinal plants are higher than expected at low elevations. The highest richness of medicinal plants at low elevation could be possibly due to favorable environmental factors such as high temperature, rainfall, sunlight or due to higher density of human population and thus higher pressure on use of any plants in lower elevations.
Ethnopharmacological relevance: Rheum australe D. Don (Polygonaceae) has been commonly used in tr... more Ethnopharmacological relevance: Rheum australe D. Don (Polygonaceae) has been commonly used in traditional medicine for a wide range of ailments related to the circulatory, digestive, endocrine, respiratory and skeletal systems as well as to infectious diseases. Aim of the review: To provide the up-to-date information that is available on the botany, traditional uses, phytochemistry, pharmacology and toxicology of Rheum australe. Additionally, to highlight the possible uses of this species to treat different diseases and to provide a basis for future research. Materials and methods: The present review covers the literature available from 1980 to 2011. The information was collected from scientific journals, books, theses and reports via a library and electronic search (Google Scholar, Web of Science and ScienceDirect). Results: Ethnomedical uses of Rheum australe have been recorded from China, India, Nepal and Pakistan for 57 different types of ailments. The phytochemical studies have shown the presence of many secondary metabolites belonging to anthraquinones, stilbenes, anthrones, oxantrone ethers and esters, chromones, flavonoids, carbohydrate, lignans, phenols and sterols. Crude extracts and isolated compounds from Rheum australe show a wide spectrum of pharmacological activities, such as antidiabetic, anti-inflammatory, antifungal, antimicrobial, antioxidant, anticancer, hepatoprotective and immuneenhancing activities, as well as a usefulness for improving renal function. Conclusion: Rheum australe has been widely used source of medicine for years without any adverse effects. Many studies have provided evidence for various traditional uses. However, there is a need for additional studies of the isolated compounds to validate the traditional uses in human models. The present review on the botany, traditional uses, phytochemistry and toxicity has provided preliminary information for further studies and commercial exploitations of the plant.
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