Remote Mountain Research Articles

The optical properties and in-situ observational evidence for the formation of brown carbon in clouds

Abstract. Atmospheric brown carbon (BrC) makes a substantial contribution to aerosol light absorption and thus global radiative forcing. Although BrC may change the lifetime of the clouds and ultimately affect precipitation, little is known regarding the optical properties and formation of BrC in the clouds. In the present study, the light-absorption properties of cloud droplet residual (cloud RES) were measured by coupled a ground-based counterflow virtual impactor (GCVI) and an aethalometer (AE-33), in addition to the cloud interstitial (cloud INT) and ambient (cloud-free) particles by PM2.5 inlet-AE-33 at Mt. Tianjing (1690 m a.s.l.), a remote mountain site in southern China, from November to December 2020. Meanwhile, the light-absorption and fluorescence properties of water-soluble organic carbon (WSOC) in the collected cloud water and PM2.5 samples were also obtained, associated with the concentration of water-soluble ions. The mean light-absorption coefficient (Abs370) of the cloud RES, cloud INT, and cloud-free particles were 0.25 ± 0.15, 1.16 ± 1.14, and 1.47 ± 1.23 Mm−1, respectively. The Abs365 of WSOC was 0.11 ± 0.08 Mm−1 in cloud water and 0.40 ± 0.31 Mm−1 in PM2.5, and the corresponding mass absorption efficiency (MAE365) was 0.17 ± 0.07 and 0.31 ± 0.21 m2 g−1, respectively. A comparison of the light-absorption coefficient between BrC in cloud RES and cloud INT particles, and WSOC in cloud water and PM2.5 indicates a considerable contribution (48 %–75 %) of water-insoluble BrC to total BrC light absorption. Secondary BrC estimated by minimum R squared (MRS) method dominated the total BrC in cloud RES (67 %–85 %), rather than in the cloud-free (11 %–16 %) and cloud INT (9 %–23 %) particles. It may indicate the formation of secondary BrC during cloud processing. Supporting evidence includes the enhanced WSOC and dominant contribution of the secondary formation and biomass burning factor (>80 %) to Abs365 in cloud water provided by positive matrix factorization (PMF) analysis. In addition, we showed that the light absorption of BrC in cloud water was closely related to humic-like substances and tyrosine-like and/or protein-like substances (r>0.63, p<0.01), whereas only humic-like substances for PM2.5, as identified by excitation-emission matrix fluorescence spectroscopy.

Morphological and Functional Change of Rural Settlements in the High Himalayan Region: A Case Study of Arakot, Uttarkashi

In the past few years, many settlements in the high Himalayan region have witnessed morphological and functional change. These changes or transformations are a manifestation of livelihood diversification in these areas. The emerging (new) opportunities in remote rural areas have brought changes in the socioeconomic conditions of the people living therein. The new developments were accompanied by a functional change of isolated mountain settlements. As a result, these settlements have got transformed into multifunctional areas. All these changes are reflected in the spatial variations and accompanied changes in settlement characteristics. The aim of this research is to identify the functional changes in remote mountain villages. The study area for this research is an isolated mountain valley in the high Himalayan region. It is a remote area of Uttarkashi, India. This area is regarded as a marginal region. The marginality of the area is the product of spatial isolation and remoteness. However, some of the settlements of this region have witnessed profound changes in the recent past. Different signs of change in settlement characteristics (morphological and functional change) have been observed in these mountain villages. There have been changes in the nature of agriculture in some of these settlements. These changes have been accompanied by a change in land use and the morphological elements of the villages. Changes in social infrastructure and standards of living are also important signs of change. This research presents a study of changes in settlement characteristics (morphological and functional change) in one of the villages of this remote mountainous area. It can be interpreted as an illustration of the development of multifunctional rural settlements in a marginal area. There is a need to capture the current processes of transformation. It may offer an essential clue for rural revitalization in the high mountain areas.

Thinning the thickets: Foraging of hardy cattle, sheep and goats in green alder shrubs

Abstract Green alder shrubs Alnus viridis increasingly overgrow European mountain pastures but hinder natural forest succession. This nitrogen‐fixing, autochthonous invasive species has numerous negative effects including the loss of biodiversity and landscape aesthetic, eutrophication of soils and downstream waters, and greenhouse gas emission. Over centuries, A. viridis encroachment was impeded by grazing livestock, particularly goats. However, in modern agriculture, livestock numbers decreased on remote mountain pastures and goat farming became unprofitable. A grazing experiment tested if hardy breeds of the more economically attractive livestock species, cattle and sheep can replace goats as A. viridis antagonists. On a subalpine pasture heavily encroached by A. viridis, space use and debarking (bark foraging) by Dexter cattle, Engadine sheep and Pfauen goats were analysed using GPS tracking and vegetation mapping. Dexter cattle used space least evenly (Camargo evenness: cattle = 0.39; sheep = 0.52; and goats = 0.47) and preferred flat slopes and open pastures. They spent least time foraging in A. viridis stands (relative presence while foraging: cattle = 0.55; sheep = 0.76; and goats = 0.80). Dexter cattle did not debark any A. viridis, but damaged shrubs by trampling. Engadine sheep visited A. viridis stands nearly as often as goats, but preferred flat slopes, short vegetation and shrub edges more clearly than goats. This sheep breed debarked significantly more A. viridis branches (average 244 branches per paddock; 7.4% of all A. viridis branches) than goats (45; 0.8%). Goats preferred mountain‐ash shrubs Sorbus aucuparia covering only 2% of the shrub layer. Synthesis and applications. Green alder shrubs, controlled by goats traditionally, overgrow valuable mountain pasture ecosystems today. Cattle, kept instead of goats, may slow down but not hinder shrub encroachment, because they avoid shrub stands and do not debark green alder. However, this study is the first to show that Engadine sheep are even better suited for green alder clearance than goats. Moreover, if management goals include forest re‐establishment, Engadine sheep outperform goats, because they debark green alder (which hinders forest regeneration), but do not destroy elderberry—a valuable forest pioneer. Hardy breeds are an important tool to maintain biodiverse, open pastures, restore natural mountain forests and mitigate the negative environmental effects of shrub encroachment.

Negritos in Taiwan and the wider prehistory of Southeast Asia: new discovery from the Xiaoma Caves

ABSTRACTTaiwan is known as the homeland of the Austronesian-speaking groups, yet other populations already had lived here since the Pleistocene. Conventional notions have postulated that the Palaeolithic hunter-gatherers were replaced or absorbed into the Neolithic Austronesian farming communities. Yet, some evidence has indicated that sparse numbers of non-Austronesian individuals continued to live in the remote mountains as late as the 1800s. The cranial morphometric study of human skeletal remains unearthed from the Xiaoma Caves in eastern Taiwan, for the first time, validates the prior existence of small stature hunter-gatherers 6000 years ago in the preceramic phase. This female individual shared remarkable cranial affinities and small stature characteristics with the Indigenous Southeast Asians, particularly the Negritos in northern Luzon. This study solves the several-hundred-years-old mysteries of ‘little black people’ legends in Formosan Austronesian tribes and brings insights into the broader prehistory of Southeast Asia.

Brief communication: Application of a muonic cosmic ray snow gauge to monitor the snow water equivalent on alpine glaciers

Abstract. Monitoring the snow water equivalent (SWE) in the harsh environments of high mountain regions is a challenge. Here, we explore the use of muon counts to infer SWE. We deployed a muonic cosmic ray snow gauge (μ-CRSG) on a Swiss glacier during the snow-rich winter season 2020/21 (almost 2000 mm w.e.). The μ-CRSG measurements agree well with measurements by a neutronic cosmic ray snow gauge (n-CRSG), and they lie within the uncertainty of manual observations. We conclude that the μ-CRSG is a highly promising method to monitor SWE in remote high mountain environments with several advantages over the n-CRSG.

Complex chemical cocktail, containing insecticides diazinon and permethrin, drives acute toxicity to crustaceans in mountain lakes

Mountain lakes have long been perceived as pristine environments. However, atmospheric deposition of persistent organic pollutants (POPs) have been shown to expose these sensitive ecosystems to chemical pollution. Little is known on how this pollution impacts aquatic ecosystems at high altitudes. We combined passive sampling with liquid and gas chromatography high resolution mass spectrometry (LC- and GC-HRMS) to screen the water of eight lakes in three different regions of the French Pyrenees. In total, we screened for 479 organic chemicals including POPs, polycyclic aromatic hydrocarbons (PAHs), legacy and current-use pesticides, biocides, and musk fragrances. We detected a complex cocktail of 151 individual chemicals and used their toxic unit summation (ΣTU) to assess toxicity for crustaceans and algae. While risks for algae never reached chronic risks, this was always the case for crustaceans. Acute toxic risk thresholds for crustaceans were even exceeded in several of our sites. At sites with acute toxic risk levels (> 0.1 ΣTU) crustaceans were completely absent or showed a low abundance. We conclude that crustaceans were at least partly impacted by the high toxic risks driven by the insecticides diazinon and permethrin. These drugs are widely used to protect livestock from blue tongue disease transmitted by sucking insects, suggesting free roaming livestock as local source. Our results provide important evidence on toxic chemical pollution in relatively remote mountain areas, with important consequences for aquatic mountain ecosystems.

Fecal indicator organisms in northern oligotrophic rivers: An explorative study on Escherichia coli prevalence in a mountain region with intense tourism and reindeer herding

Increasing pollution levels in waters from remote mountain areas in northern Sweden have been observed. To support a sustainable water quality management, it is necessary to know which environmental and antrophogenic factors influence the water quality. The purpose of this study was to map the Escherichia coli prevalence in the catchment area of the upper part of a large northern Scandinavian river and investigate the controlling factors of microbial contamination. A total of 112 water samples were collected from various locations in the research area between July 2020 and December 2020. These samples were analyzed for microbial and chemical characteristics, and information about tourism and reindeer herding was compiled. Additionally, microbial and physicochemical water characteristics collected by Indalsälven Water Conservation Association (IWCA, 1993–2020) and Swedish Meteorological and Hydrological Institute (SMHI, 2004–2020) were analyzed. The results showed that E. coli enumerations ranged between 0 and 500 CFU/100 ml. There was generally no obvious relation between suspected point sources, e.g., sewage treatment plants at mountain stations, and E. coli levels at downstream sampling points. Principal component analysis showed that E. coli was correlated to coliforms, total heterotrophic count, river discharge, CODMn and river color. Since microbial analyses are time-consuming, expensive and difficult to perform in remote areas, it is important to find more easily extracted water parameters that can serve as a proxy for E. coli. In particular, river color and discharge are promising parameters that may serve as an early indication of bacterial outbreak and fecal contamination in mountain waters.

Airborne microplastics: A review of current perspectives and environmental implications

Microplastics (MPs), as an entirely anthropogenic type of pollution, are considered to be stratigraphic markers of the Anthropocene Epoch, and have become of increasing public concern over the past decade. Recent studies have revealed that the atmosphere is an efficient medium to disseminate MPs from their sources to remote mountains and marine areas. However, current research on atmospheric MPs (i.e. airborne MPs) is generally less highlighted than MP water and soil pollution studies due to the lack of standard methods for the identification and quantification of atmospheric MPs. This paper reviews the published literature on airborne MPs, gives an overview of the advantages and disadvantages of current airborne MPs collection techniques, extraction methods and identification (i.e., ‘passive’ and ‘active’ sampling, density separation and visual identification), and lays a foundation for future studies. The physical and chemical characteristics, classification, spatial and temporal scale distributions, sources, transport, and environmental impacts of airborne MPs are summarized. There are substantial research gaps in the quantification of airborne MPs and the exploration of toxicity mechanisms of inhalable MPs. The establishment of accredited methods is an urgent challenge for a better understanding on airborne MPs and their environmental and health effects. As one of the constituents in many aerosols, airborne MPs should be treated as a recognized pollutant for long-term monitoring, and the factors that specifically affect airborne MPs could be better addressed by means of the characterization of individual MPs. In the future, the effects and interaction of MPs in the atmosphere, lithosphere and hydrosphere are also of critical importance.

Development of a graphical resilience framework to understand a coupled human-natural system in a remote arid highland of Baja California Sur.

Hydrological systems are important to society as water resources and effective management requires an understanding of how water and humans influence each other. To describe human-water connections it is necessary to bridge social and natural sciences. To this end, we construct an interdisciplinary graphical framework for evaluating potential human-water system resilience, which is a tool to show the spatial and temporal response to system change of both human and natural systems. This helps to identify the ways that human responses to change relate to changing water resources and identifies important thresholds and potential disconnects that would create vulnerability. We further use this tool to describe a dynamic, coupled human-water system present in the arid Sierra de la Giganta region of Baja California Sur, Mexico. In this remote mountain range, there is a community (self-identifying as Choyeros) who rely on spring water for ranching and subsistence. Using mixed methods of hydrogeochemistry and anthropology, we describe spatial connectivity and temporal changes of both hydrologic and social systems. We use these observations to examine the Choyero response to system changes and explore the topology of the various approaches that the community employs to adapt to changing water availability. The framework guides dialogue to constrain the types of policies, strategies, and responses that help to promote the sustainability of water resources. This framework can be used to compare systems across spatio-temporal scales to produce more generalizable and communicable insights of coupled human-natural systems.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11625-022-01101-6.

Spatiotemporal variation characteristics of ecosystem health and its driving mechanism in the mountains of southwest China

A deeper understanding of the spatiotemporal variation characteristics of ecosystem health and its driving mechanism are important for ecosystem management and restoration. Under the complex environment in the southwestern mountainous area of China, various natural and anthropogenic factors interact with each other, complicating the mechanism driving ecosystem health. Quantitatively exploring the interaction among driving factors is challengeable but worthwhile. Based on the pressure–state–response (PSR) framework, the ecosystem health value of the study area was computed for the years of 2000 and 2018 at the grid scale. A geographical detector model was adopted to explore the factors driving ecosystem health change. We found that, compared to the year of 2000, there was an improvement in ecosystem health in 2018. The most significant improvement occurred in ample rural areas scattered in remote mountain areas. Nevertheless, there were grids experiencing ecosystem health deterioration. The appearance of a “deterioration ring” surrounding the metropolis region was the typical representative. Among the 10 selected driving factors, in-migrant population, out-migrant population, population density, elevation, and slope were found to be the most important factors. There were obvious impact thresholds of elevation, slope, distance to towns and distance to road on ecosystem health change. The out-migrant population in rural areas strongly promoted the local ecosystem health improvement by alleviating the pressure of human activity. In contrast, the in-migrant population presented the opposite effects on ecosystem health. All driving factors produced enhanced effects on the ecosystem health change through interaction effects. The largest enhanced effects occurred between the migrant population (in- and out-migrant) and the other eight driving factors. Our findings emphasize the key role of migrant population in ecosystem health change, which has not been considered in previous studies.

Evidence for multiple potential drivers of increased phosphorus in high-elevation lakes

Total phosphorus (TP) concentrations have increased in many remote mountain waterbodies across the western United States, and reports of algal blooms in these systems have increased in frequency. Explanations for observed TP increases are uncertain, and typical landscape drivers, such as agricultural/urban runoff, are implausible. We investigated multiple atmospheric and terrestrial-P loading mechanisms to explain the observed decadal increase in TP, including a novel hypothesis that warming soils may lead to elevated P fluxes to receiving water bodies. Using northern Utah mountains ranges as a case study, we measured prospective inputs of total and bioavailable P via dust deposition. Terrestrial loading was evaluated through soil leaching experiments designed to simulate soil acidification and recovery, as well as observed decadal increases in soil temperatures and extended growing season. In the Uinta Mountains, dust-P flux appears to be one of the most plausible mechanisms for P increases where we estimated bioavailable dust-P loading ranged from 1.6 to 23.1 mg P m−2 yr−1. However, our results revealed that an increase of soil pH by 0.5 units could lead to a rise in leached P, ranging from 4.7 to 65 mg P m−2. Rising temperatures also showed the potential to increase soil P leaching; Observed average historical (~ +3 °C) and future (+2 °C) increases in temperature led to a prospective increase in leached P from 2 to 264 mg SRP m−2. While we found that pH shifts can mobilize significant amounts of P in some locations, we found no evidence of pH changes through time in the Uinta Mountains. However, summer soil temperatures increased at most locations. The mechanisms evaluated in this study can help explain the widespread observed increases in P across Western US lakes, but the mechanisms that dominate in any given region are likely to vary based on local to regional factors.

Two New Species of Metapocyrtus Heller, 1912 (Coleoptera: Pachyrhynchini) from Mount Natampod, Pantaron Range, Bukidnon, Mindanao, Philippines

Mindanao is home to many unknown weevil species, specifically those remote and unexplored mountain ecosystems. Two new species, Metapocyrtus (Metapocyrtus) mendioi sp. nov. and M. (M.) edmai sp. nov. are described from Mount Natampod, Pantaron Range, San Fernando, Bukidnon, Mindanao, Philippines. Habitat, ecology, and threats are provided. Moreover, a distribution map of all known Metapocyrtus species in the Philippine archipelago is also provided.

Interdecadal variation in sediment yield from a forested mountain basin: The role of hydroclimatic variability, anthropogenic disturbances, and geomorphic connectivity

Variation in sediment yield may reflect a signal of disturbances in the upstream landscape, modified by sediment routing. This study, conducted in a forested drainage basin in the inland Pacific Northwest, USA, sought to generate a better insight into the interdecadal variability of sediment yield in mountain landscapes in response to environmental change during the last century. To this end, we examined: (1) sediment yield fluctuations; and (2) their association with streamflow and land use changes; as well as (3) streamflow links to climate variability modes; and (4) the influence of sediment delivery from hillslope sources to streams (lateral connectivity) and its downstream routing through the stream network (longitudinal connectivity) on land use signal at the basin's outlet. Sediment yield between 1910 and 2017, estimated based on reconstructed fluvial delta growth, displayed an order of magnitude variability, which indicates a substantial geomorphic sensitivity. The interpretation of temporal patterns and an exploratory statistical analysis pointed to land use-related sediment supply changes as the primary driver of these fluctuations, dominating system behavior before changes in environmental regulations and practices in the mid-1970s. Hydroclimatically controlled streamflow variability appeared to be more prominent in the subsequent period. Our connectivity analysis suggested that a considerable portion of coarse sediment mobilized by harvest and road construction may still reside within the channel network. In light of previous research in this landscape system, we speculate that, despite limited anthropogenic pressures in the recent decades, its characteristics and behavior continue to be conditioned by land use legacies. Overall, this study contributes to the growing understanding of profound anthropogenic transformation of the earth surface. Specifically, it demonstrates that historical resource extraction may have left a lasting imprint even in relatively remote mountain landscapes. Given the ongoing rapid environmental change, such understanding is crucial for watershed management, conservation, and restoration.

Which sustainability objectives are difficult to achieve? The mid-term evaluation of predicted scenarios in remote mountain agricultural landscapes in Slovakia

The Poloniny National Park (Poloniny) is a forest/grassland-dominated ecosystem, peripherally located on the Slovakian border with Ukraine and Poland, with low population density, economic insufficiency and high natural and cultural values. Three different scenarios for agricultural landscape development were outlined for Poloniny in 2005 under the BioScene project and their likely contributions to achieving participatory-selected sustainability objectives were assessed. Our current research aims to evaluate the recent trends in achieving these sustainability objectives in a socio-ecological context and within the scope of the 2005 scenarios. In addition, we searched for generic and site-specific interventions that could halt the collapse of the socio-ecological system of such landscapes, paying attention to tourism which has appeared to be a promising factor in the region’s socio-economic progress in recent times. We employed information from key planning documents, statistical data on demography, changes in agricultural land use, changes seen from geo-tagged photos, and two questionnaire surveys with local stakeholders. The first survey included feedback on achieving the 2005 sustainability objectives and perceived changes in land use and management; the second aimed to find out the number of accommodated visitors in recent years. Based on sustainability appraisal, we conclude that there has been a mixed impact on biodiversity and natural resources, and a negative or stagnating trend for most social and economic aspects, especially social infrastructure for promotion of local job creation and maintaining the local population. Furthermore, changes in agricultural land use reflect farming activities optimised to local biophysical conditions and toward reaching farm efficiency under the conditions set by the Common Agricultural Policy. Nevertheless, ecotourism was found to be an opportunity in stimulating multi-functional and sustainable landscape management: ecotourism has significantly expanded in the last few years, especially due to local initiatives, and has been further accelerated by the COVID-19 pandemic. However, its long-term maintenance is uncertain since its linkage to the well-being of the local community is absent. For achieving this objective, we recommend systematic design of targeted rural policy which respects the needs and character of peripheral mountain regions, provides better conditions for sustainable farming, especially in connection with nonproduction benefits from agricultural landscape such as recreation and biodiversity, and considers local actions and knowledge.

Global dispersal and potential sources of antibiotic resistance genes in atmospheric remote depositions.

Antibiotic resistance has become a major Global Health concern and a better understanding on the global spread mechanisms of antibiotic resistant bacteria (ARB) and intercontinental ARB exchange is needed. We measured atmospheric depositions of antibiotic resistance genes (ARGs) by quantitative (q)PCR in rain/snow collected fortnightly along 4 y. at a remote high mountain LTER (Long-Term Ecological Research) site located above the atmospheric boundary layer (free troposphere). Bacterial composition was characterized by 16S rRNA gene sequencing, and air mass provenances were determined by modelled back trajectories and rain/snow chemical composition. We hypothesize that the free troposphere may act as permanent reservoir and vector for ARB and ARGs global dispersal. We aimed to i) determine whether ARGs are long-range intercontinental and persistently dispersed through aerosols, ii) assess ARGs long-term atmospheric deposition dynamics in a remote high mountain area, and iii) unveil potential diffuse ARGs pollution sources. We showed that the ARGs sul1 (resistance to sulfonamides), tetO (resistance to tetracyclines), and intI1 (a proxy for horizontal gene transfer and anthropogenic pollution) were long-range and persistently dispersed in free troposphere aerosols. Major depositions of tetracyclines resistance matched with intensification of African dust outbreaks. Potential ARB mostly traced their origin back into agricultural soils. Our study unveils that air masses pathways are shaping ARGs intercontinental dispersal and global spread of antibiotic resistances, with potential predictability for interannual variability and remote deposition rates. Because climate regulates aerosolization and long-range air masses movement patterns, we call for a more careful evaluation of the connections between land use, climate change and ARB long-range intercontinental dispersal.

The number of tree species on Earth

One of the most fundamental questions in ecology is how many species inhabit the Earth. However, due to massive logistical and financial challenges and taxonomic difficulties connected to the species concept definition, the global numbers of species, including those of important and well-studied life forms such as trees, still remain largely unknown. Here, based on global ground-sourced data, we estimate the total tree species richness at global, continental, and biome levels. Our results indicate that there are ∼73,000 tree species globally, among which ∼9,000 tree species are yet to be discovered. Roughly 40% of undiscovered tree species are in South America. Moreover, almost one-third of all tree species to be discovered may be rare, with very low populations and limited spatial distribution (likely in remote tropical lowlands and mountains). These findings highlight the vulnerability of global forest biodiversity to anthropogenic changes in land use and climate, which disproportionately threaten rare species and thus, global tree richness.

都市域から離れた高山で検出されたマイクロプラスチック

都市域から離れた高山で検出されたマイクロプラスチック

The Human Connection: First Evidence of Microplastics in Remote High Mountain Lakes of Sierra Nevada, Spain

The Human Connection: First Evidence of Microplastics in Remote High Mountain Lakes of Sierra Nevada, Spain

160 glacial lake outburst floods (GLOFs) across the Tropical Andes since the Little Ice Age

Assessing the extent to which glacial lake outburst floods (GLOFs) are increasing in frequency in modern times and whether their incidence is driven by anthropogenic climate change requires historical context. However, progress on this issue is hampered by incomplete GLOF inventories, especially in remote mountain regions. Here, we exploit high-resolution, multi-temporal satellite and aerial imagery, and documentary data to identify GLOF events across the glacierized Cordilleras of Peru and Bolivia, using a set of diagnostic geomorphic features. A total of 160 GLOFs from 151 individual sites are characterised and analysed, tripling the number of previously reported events. We provide statistics on location, magnitude, timing and characteristics of these events with implications for regional GLOF hazard identification and assessment. Furthermore, we describe several cases in detail and document a wide range of process chains associated with Andean GLOFs. • Our inventory consists of 160 glacial lake outburst floods (GLOFs). • About two thirds of these have not been identified previously in the literature. • We analyze spatial and temporal patterns of GLOF occurrence. • We characterize pre-conditions, triggers and mechanisms of GLOFs.

Ecology and Ethnobotany in and around Api Nampa Conservation Area (ANCA), Darchula, Nepal

Background: Far-Western mountainous Region of Nepal is a rich source of floral diversity and medicinal plants. The latter is frequently being used in traditional healing systems in the region. In the present study, we aimed to document richness and diversity of flowering plant species including medicinal species and their indigenous uses in Api Nampa Conservation Area (ANCA) of Darchula district, Far Western Nepal. To be precise, we explored the detail ethnobotanical accounts of Hippophae species of the area. Methods: Fieldwork for this study was carried out twice in July 2019 and July 2020. Ghajir Kshetti, Khirsha and Lamthing villages of eastern ANCA (considered as a protected site, government managed) and Patha, Ranghadi, Kantai and Batheldhunga villages of northern ANCA (considered as community-managed site) were sampled. A total of ten quadrats each measuring 10 m x 10 m size in each site was laid to inventory the species and analyze the ecological traits. For ethnobotanical assessment, two field observations were made and 20 people, representing male, female, senior citizens were interviewed. Supplementary information was collected during informal group discussions held in the villages and in district center. Results: We recorded 76 plant species including Hippophae salicifolia in two different study sites of ANCA, Darchula. The species belonged to 33 families and 62 genera. The dominant plant families were Pinaceae, Rosaceae, Poaceae, Ericaceae and Asteraceae. The comparative assessment showed that the protected site has greater number plant species 60 (78.94%) whereas the northern ANCA site has only 37 (48.68%) species. The highest IVI (26.95) was recorded for Hippophae salicifolia and minimum (2.37) for Daphne papyracea. As dominant, the Hippophae salicifolia was frequently used traditionally for primary health care, local livelihood, nutrition, cosmetics, and environmental management. Out of 76, 65 species were used for ethnobotany and 11 species for ethnomedicine. Conclusions: Protected ANCA site is rich in plant species. The site and whole ANCA are dominated by useful plant species such as Hippophae salicifolia, Alnus nepalensis, Elaeagnus parvifolia, Girardiania diversifolia, Ilex excelsa, Juglans regia, etc. This study contributes to the wealth of medicinal plants and ethnobotany of ANCA, Darchula. Conservation of useful plant species complements the rural livelihood inhabiting the rugged and remote mountains of Far-Western Nepal. Key words: Api Nampa Conservation Area, Diversity, Darchula, Ethnobotany, Seabuckthorn.