Alpine Ecosystems Research Articles

Soil carbon stabilization and potential stabilizing mechanisms along elevational gradients in alpine forest and grassland ecosystems of Southwest China

Alpine ecosystems potentially store a large amount of soil organic carbon (SOC), but they are highly sensitive to climate change. The assessment of SOC stabilization mechanisms in these ecosystems is therefore vital to understanding the C dynamics in terrestrial ecosystems. Here, we investigated the soil aggregate distribution, aggregate stability, and associated SOC contents within alpine forest and grassland soils along an elevation gradient (2600–3900 m a.s.l) in the Yulong Mountains of Southwest China. Our results showed that the SOC contents in bulk soils and aggregates were higher within grassland soils than in forestland soils, with higher levels in the topsoil (0–10 cm) than in the subsurface soil (10–20 cm) layers at each elevation. The large macroaggregates (>2000 µm) accounted for the largest proportions of aggregate fractions (50.54% and 49.11%) and contributed the greatest proportions of C (55.44% and 52.12%) to the whole soil C within forest and grassland soils, respectively. Generally, the proportions of large macroaggregates, microaggregates (53–250 µm), mean weight diameter, and geometric mean diameter increased significantly with increasing elevation across different soil depths and land types, suggesting that soil C stability was improved with increasing elevation. The SOC contents in bulk soils and aggregates also showed an increasing trend with increasing elevation, with the highest level observed at 3900 m within forestland and 3200 and 3900 m within grassland soils at both soil depths. Climate factors, soil factors, Al/Fe oxides, and aggregate stability indices interactively explained 86% and 52% of the variation in soil C within forest and grassland soils, respectively. Among them, the incorporation of the Al/Fe oxides increased the total explained SOC variations by approximately 10%, exceeding the SOC variations explained by climate or soil factors. Overall, our results provide useful insights into the patterns and mechanisms of soil C stabilization along elevation gradients in alpine ecosystems.

A functional metagenomics study of soil carbon and nitrogen degradation networks and limiting factors on the Tibetan plateau.

The Three-River Source Nature Reserve is located in the core area of the Qinghai-Tibetan Plateau, with the alpine swamp, meadow and steppe as the main ecosystem types. However, the microbial communities in these alpine ecosystems, and their carbon and nitrogen degrading metabolic networks and limiting factors remain unclear. We sequenced the diversity of bacteria and fungi in alpine swamps, meadows, steppes, and their degraded and artificially restored ecosystems and analyzed soil environmental conditions. The results indicated that moisture content had a greater influence on soil microbial community structure compared to degradation and restoration. Proteobacteria dominated in high moisture alpine swamps and alpine meadows, while Actinobacteria dominated in low moisture alpine steppes and artificial grasslands. A metabolic network analysis of carbon and nitrogen degradation and transformation using metagenomic sequencing revealed that plateau microorganisms lacked comprehensive and efficient enzyme systems to degrade organic carbon, nitrogen, and other biological macromolecules, so that the short-term degradation of alpine vegetation had no effect on the basic composition of soil microbial community. Correlation analysis found that nitrogen fixation was strong in meadows with high moisture content, and their key nitrogen-fixing enzymes were significantly related to Sphingomonas. Denitrification metabolism was enhanced in water-deficient habitats, and the key enzyme, nitrous oxide reductase, was significantly related to Phycicoccus and accelerated the loss of nitrogen. Furthermore, Bacillus contained a large number of amylases (GH13 and GH15) and proteases (S8, S11, S26, and M24) which may promote the efficient degradation of organic carbon and nitrogen in artificially restored grasslands. This study illustrated the irrecoverability of meadow degradation and offered fundamental information for altering microbial communities to restore alpine ecosystems.

Grazing intensity alters soil microbial diversity and network complexity in alpine meadow on the Qinghai-Tibet Plateau

Livestock grazing can alter biodiversity and ecosystem functions. However, how long-term and continuous grazing intensity affect belowground biodiversity remains unclear, especially for soil microbial diversity. Here, through a well-controlled 5-year field experiment in a Tibetan alpine meadow, the responses of soil bacterial and fungal communities to yak grazing intensity were examined. Our results showed that grazing intensity significantly changed soil bacterial and fungal community compositions, rather than microbial α-diversity. The co-occurrence network analysis indicated that both soil bacterial and fungal network complexity gradually decreased with increasing grazing intensities. Meanwhile, soil C/N ratio, soil moisture, dissolved organic nitrogen (DON), NH4+-N, and aboveground biomass (AGB) were related to soil bacterial community, and AGB, NO3--N, NH4+-N, and DON and were associated with soil fungal community. Taken together, our manipulative experiment provides empirical evidence that grazing intensity-induced alterations of aboveground vegetation and nitrogen availability primarily trigger the shift of soil microbial community and structure. These results can support grassland management and ecological restoration in alpine ecosystems.

Ecosystem Service Relationships, Drivers, and Regulation Strategies in a Degraded Alpine Shrub Meadow on the Northeastern Qinghai-Tibetan Plateau

One of the challenges of managing grasslands sustainably is the conflict between the different ecosystem services they provide. This is especially evident in the Qinghai-Tibetan Plateau (QTP) region, where fragile alpine ecosystems make balancing the needs of grassland conservation and development difficult. However, our current understanding of the relationships and drivers of ecosystem services in degraded alpine shrub meadows on the QTP is insufficient. To address this, we studied forage provisioning and water retention services in a degraded alpine shrub meadow in the northeastern QTP. We analyzed the changes and relationships between these services at different levels of degradation and identified those factors that influenced ecosystem service relationships. The results showed that the forage supply service and the water retention service of the alpine shrub meadow increased and decreased by 23.6% and 27.07%, respectively, due to degradation. The trade-offs between these two services varied depending on the degree of degradation, with light and moderate degradation showing a preference for water retention service, and heavy and extreme degradation showing a preference for forage supply. Water retention was constrained by forage supply and both services showed an exponential function form of decay. The physical and chemical properties of the soil in the alpine shrub meadow remained relatively stable during the degradation process, with only soil organic carbon (SOC), total potassium (TK), and total nitrogen (TN) decreasing significantly. SOC may have indirectly influenced the relationship between the two services by affecting water retention. This study provides insights into alpine shrub meadow management and conservation on the QTP.

Coexistence of European hares and Alpine mountain hares in the Alps: what drives the occurrence and frequency of their hybrids?

AbstractAs a glacial relict species, mountain hares are adapted to cold and snowy conditions. Conversely, European hares originate from the grasslands of the Middle East and spread from there throughout low‐lying agricultural areas of Europe. Mountain hares and European hares generally occur allopatrically, however, sympatry occurs in some areas. In sympatric areas, introgressive hybridisation poses a threat to the Alpine mountain hare by reducing its genetic integrity. Introgressed individuals can be found in both species but are far more frequent in European hares than in mountain hares. The ecology of hybrids is poorly known in these species. To examine the Alpine mountain hare and European hare populations in the Alps with a particular focus on the occurrence and ecology of their hybrids, we performed molecular genetic analysis of hare faecal samples collected in four study areas in the Alps in South Tyrol for three winters and compared habitat associations of the genotyped samples. We recorded 150 individuals (i.e. 14 hybrids, 25 European hares and 111 Alpine mountain hares). Four introgressed individuals were at levels consistent with F2 hybrids, whereas the others showed an older interspecific gene flow. We found that hybrid faeces tended to be at lower elevations compared to those of Alpine mountain hare but at higher elevations than those of the European hare. The frequency of Alpine mountain hares decreased as the proportion of Alpine grassland increased but was positively correlated with the proportion of dwarf shrub heaths. No effect of vegetation type was found for the frequency of European hares and hybrids. Our results support the widely raised concerns that the European hare, as a generalist, is a strong competitor with the Alpine mountain hare in the Alpine ecosystem in the time of global climate change.

Genome-environment associations along elevation gradients in two snowbed species of the North-Eastern Calcareous Alps

BackgroundAnthropogenic climate change leads to increasing temperatures and altered precipitation and snowmelt patterns, especially in alpine ecosystems. To understand species’ responses to climate change, assessment of genetic structure and diversity is crucial as the basis for the evaluation of migration patterns, genetic adaptation potential as well as the identification of adaptive alleles.ResultsWe studied genetic structure, diversity and genome-environment associations of two snowbed species endemic to the Eastern Alps with a large elevational range, Achillea clusiana Tausch and Campanula pulla L. Genotyping-by-sequencing was employed to assemble loci de novo, call variants and perform population genetic analyses. Populations of either species were distinguishable by mountain, and to some extent by elevation. We found evidence for gene flow between elevations. Results of genome-environment associations suggested similar selective pressures acting on both species, emanating mainly from precipitation and exposition rather than temperature.ConclusionsGiven their genetic structure and amount of gene flow among populations the two study species are suitable to serve as a model for genetic monitoring of climate change adaptation along an elevation gradient. Consequences of climate change will predominantly manifest via changes in precipitation and, thus, duration of snow cover in the snowbeds and indirectly via shrub encroachment accompanied by increasing shading of snowbeds at lower range margins. Assembling genomes of the study species and studying larger sample sizes and time series will be necessary to functionally characterize and validate the herein identified genomic loci putatively involved in adaptive processes.

Weekly high-resolution multi-spectral and thermal uncrewed-aerial-system mapping of an alpine catchment during summer snowmelt, Niwot Ridge, Colorado

Abstract. Alpine ecosystems are experiencing rapid change as a result of warming temperatures and changes in the quantity, timing and phase of precipitation. This in turn impacts patterns and processes of ecohydrologic connectivity, vegetation productivity and water provision to downstream regions. The fine-scale heterogeneous nature of these environments makes them challenging areas to measure with traditional instrumentation and spatiotemporally coarse satellite imagery. This paper describes the data collection, processing, accuracy assessment and availability of a series of approximately weekly-interval uncrewed-aerial-system (UAS) surveys flown over the Niwot Ridge Long Term Ecological Research site during the 2017 summer-snowmelt season. Visible, near-infrared and thermal-infrared imagery was collected. This unique series of 5–25 cm resolution multi-spectral and thermal orthomosaics provides a unique snapshot of seasonal transitions in a high alpine catchment. Weekly radiometrically calibrated normalised difference vegetation index maps can be used to track vegetation health at the pixel scale through time. Thermal imagery can be used to map the movement of snowmelt across and within the near sub-surface as well as identify locations where groundwater is discharging to the surface. A 10 cm resolution digital surface model and dense point cloud (146 points m−2) are also provided for topographic analysis of the snow-free surface. These datasets augment ongoing data collection within this heavily studied and important alpine site; they are made publicly available to facilitate wider use by the research community. Datasets and related metadata can be accessed through the Environmental Data Initiative Data Portal, https://doi.org/10.6073/pasta/dadd5c2e4a65c781c2371643f7ff9dc4 (Wigmore, 2022a), https://doi.org/10.6073/pasta/073a5a67ddba08ba3a24fe85c5154da7 (Wigmore, 2022c), https://doi.org/10.6073/pasta/a4f57c82ad274aa2640e0a79649290ca (Wigmore and Niwot Ridge LTER, 2021a), https://doi.org/10.6073/pasta/444a7923deebc4b660436e76ffa3130c (Wigmore and Niwot Ridge LTER, 2021b), https://doi.org/10.6073/pasta/1289b3b41a46284d2a1c42f1b08b3807 (Wigmore and Niwot Ridge LTER, 2022a), https://doi.org/10.6073/pasta/70518d55a8d6ec95f04f2d8a0920b7b8 (Wigmore and Niwot Ridge LTER, 2022b). A summary of the available datasets can be found in the data availability section below.

Differences in respiration components and their dominant regulating factors across three alpine grasslands on the Qinghai−Tibet Plateau

Greenhouse gases (GHGs) emissions from high-cold terrestrial ecosystems underlain by permafrost on the Qinghai–Tibet Plateau (QTP) have received widespread attention. However, the dominant factors regulating ecosystem respiration (Re) and its components (soil respiration Rs and heterotrophic respiration Rh) and how the differences in carbon emissions from different ecotypes and seasons remain are still unclear. We conducted a 2-year field investigation (August 2018 to October 2020) and applied the structural equation model (SEM) to clarify the changes in the factors controlling the respiration components during different seasons. The results indicate that the Re and its controlling factors in three alpine grassland ecosystems (alpine steppe, alpine meadow, and swamp meadow) vary with seasons. Furthermore, autotrophic respiration (Ra) contributes the most to the seasonal changes in Re. The Re gradually increases in the early growing season and rapidly decreases in the late growing season. Rh remains relatively stable during the year. Under these seasonal variations in the respiration components, the dominant factors controlling Re in the nongrowing season are the temperature of the atmosphere–soil interface (heat flux, atmospheric temperature, and soil temperature at 5 cm depth) and microbial activity (microbial carbon and pH) with the variable importance projections >1.5. During the growing season, the dominant factors regulating Re, Rs, and Rh are the soil temperature with a standardized direct effect (SDE) of 0.424, soil nutrient conditions (total nitrogen and pH) with SDEs of 0.570–0.614, and microbial activity (microbial carbon) with a SDE of 0.591, respectively. In addition, meteorological conditions have an important impact on the respiration components during the growing season. Specifically, the atmospheric vapor pressure is the dominant factor regulating the three respiration components (standardized total effects = 0.44−0.53, p < 0.001). The optimal soil water contents during the growing season (water content at which Re reaches the maximum) are 10% in the alpine steppe, 13%–15% in the alpine meadow, and 40%–43% in the swamp meadow, respectively. The effect of the soil water content on Re is more important in arid ecosystems (alpine steppe and alpine meadow) than in wet ecosystem (swamp meadow). The alleviation of water limitations in arid ecosystems may potentially increase Re.

How to effectively improve the ecosystem provisioning services in traditional agricultural and pastoral areas in China?

The provisioning services of ecosystems are fundamental for people's livelihoods, health, and survival, yet provisioning services are highly dependent on land use/cover change (LUCC), especially in fragile alpine ecosystems. In the Qilian Mountains, one of China's traditional farming and pastoral areas, changes in provisioning services are related to regional well-being. This study focuses on the multi-scale evolution, driving factors, and sustainable development strategies for providing farmland and grassland ecosystem services from 2000 to 2020. The results showed an overall upward trend in the value of providing services by grassland and cropland ecosystems over the past 20 years, increasing by US $249 million and US $67.35 million, respectively. The economic benefits of livestock products provided by grassland and agricultural products from farmland accounted for 70.5% and 29.5% of the total income of farmers and herdsmen, respectively. However, in the past 10 years, the contribution of grassland and farmland ecosystems to provisioning services has decreased by 0.2% and 1.7% respectively. The reduction of contribution will directly affect the capacity to provisioning services, which is not conducive to regional development. It is found that human factors such as policy system change, urbanization process and ideological change are the main driving factors for the change of supply services in traditional agricultural and pastoral areas, and climate change has played a certain role in promoting. In order to effectively improve the ability of traditional agricultural and pastoral areas to provide services, we put forward the development strategy of “Ecological Husbandry + Precision Agriculture (EHPA)”. and promote the “Production, Learning, Scientific research and Practical application” of ecosystem services from the five aspects of ecological space, industrial layout, ecological industrial development, ecological technology and ecological policy system, so as to improve the ability of ecosystem provisioning services.

Distribution and biodiversity of the beetle population (Coleoptera) in the alpine ecosystem of the Tatra National Park

Distribution and biodiversity of the beetle population (Coleoptera) in the alpine ecosystem of the Tatra National Park

Annual ring width in the arctic-alpine dwarf-shrub species Salix herbacea - Dataset from long-term alpine ecosystem research in central Norway (LTAER-NO)

Here, we present a datapaper containing microscopically measured data of annual ring widths in the arctic-alpine dwarf-shrub species Salix herbacea (central Norway). The dataset will be updated with future measurements.

Annual ring width in the Mediterranean-alpine shrub species Cytisus galianoi - dataset from long-term alpine ecosystem research in the Sierra Nevada, Spain (LTAER-ES)

This is a datapaper including microscopically measured data of annual ring widths from the Mediterranean-alpine shrub species Cytisus galianoi (Sierra Nevada, Spain). The dataset will be updated with future measurements.

Characteristics of near‐surface soil freeze–thaw status using high resolution CLM5.0 simulations on the Tibetan Plateau

AbstractSoil freeze–thaw alternation is a natural characteristic of the Tibetan Plateau (TP), and plays an important role in surface energy balance and eco‐hydrological processes. The soil freeze–thaw process on the TP has changed significantly owing to global warming, affecting the alpine ecosystem structure and function. This study used high‐resolution atmospheric forcing datasets to drive the Community Land Model version 5.0 (CLM5.0) to simulate the near‐surface soil freeze–thaw status between 1979 and 2020. The simulated results were compared with in situ observations, and then the spatiotemporal distribution of the freeze start‐date (FSD), freeze end‐date (FED), freeze duration (FD), and thaw duration (TD) at a depth of 0.1 m were analyzed. The Nash–Sutcliffe efficiency coefficients (NSEs) of FSD, FED, FD, and TD between simulations and in situ observations were 0.77, 0.90, 0.98 and 0.92, and the correlation coefficients of FSD, FED, FD, TD were 0.97, 0.99, 0.99 and 0.98, respectively. The spatial distribution of FSD and TD was characterized by gradually increasing from northwest to southeast while FED and FD exhibited the opposite characteristics. FSD, FED, FD, and TD changed at an area‐mean rate of 1.1, −1.4, −2.5, and 2.5 days decade−1, respectively. This study provides an important reference for analyzing and predicting the changes in near surface soil freeze–thaw status on the TP under the warming climate.

Climate-driven shifts in plant and fungal communities can lead to topsoil carbon loss in alpine ecosystems.

Alpine tundra ecosystems suffer from ongoing warming-induced tree encroachment and vegetation shifts. While the effects of tree line expansion on the alpine ecosystem receive a lot of attention, there is also an urgent need for understanding the effect of climate change on shifts within alpine vegetation itself, and how these shifts will consequently affect soil microorganisms and related ecosystem characteristics such as carbon storage. For this purpose, we explored relationships between climate, soil chemistry, vegetation, and fungal communities across seven mountain ranges at 16 alpine tundra locations in Europe. Among environmental factors, our data highlighted that plant community composition had the most important influence on variation in fungal community composition when considered in combination with other factors, while climatic factors had the most important influence solely. According to our results, we suggest that rising temperature, associated with a replacement of ericoid-dominated alpine vegetation by non-mycorrhizal or arbuscular mycorrhizal herbs and grasses, will induce profound changes in fungal communities toward higher dominance of saprotrophic and arbuscular mycorrhizal fungi at the expense of fungal root endophytes. Consequently, topsoil fungal biomass and carbon content will decrease.

Mattic epipedon fragmentation strengthened the soil infiltration capacity of a hillside alpine meadow on the Qinghai‐Tibetan Plateau

AbstractDegradation of hillside alpine meadow ecosystems is a widespread problem that usually results in the fragmentation of the mattic epipedon (ME). The mattic epipedon plays a well‐known role in the hydrological cycle of alpine ecosystems due to its high water‐holding capacity. However, little is known about how ME fragmentation alters soil infiltrability—a key soil property that influences runoff and erosion processes as well as soil moisture dynamics. To address this issue, we contrasted the infiltration rates and soil and plant characteristics of preserved meadow patches (with full ME) and patches at two stages of ME fragmentation, namely, half ME and without ME. Our results showed that mattic epipedon fragmentation reduced aboveground plant biomass (mainly of sedges) by 58.6–65.6 g m−2 and root biomass by 5,643–10,054 g m−2. Soil compressive strength (11.6 kg cm−2) and total soil porosity (52%) of fragmented meadow patches without ME were significantly lower than in those with half (17.9 cm−2 and 62%, respectively) or full ME (31.7 cm−2 and 62.5%, respectively). In contrast, non‐capillary porosity and aggregate stability slightly increased with fragmentation and were highest at patches without ME. Importantly, soil infiltration rates in hillside alpine meadows greatly increased as a result of mattic epipedon fragmentation. Initial infiltration rates were approximately 10 and 20 times higher at patches with half ME and without ME (177 mm h−1 and 326 mm h−1, respectively) than at patches with the full ME (17 mm h−1). Moreover, steady‐state infiltration rates were approximately 6 and 9 times higher at patches with half ME and without ME (60 mm h−1 and 88 mm h−1, respectively) than at patches with the full ME (17 mm h−1). Overall, mattic epipedon fragmentation improved soil infiltrability by changing the soil and plant characteristics. These findings suggest that mattic epipedon fragmentation will lower runoff maintenance and have drastic effects on the water provisioning function of hillside alpine meadows on the Qinghai‐Tibetan Plateau.

Effects of plant community and altitude on food composition of Cervus elaphus wallichii during the withered grass period on the Tibetan Plateau, China.

How Tibetan red deer (Cervus elaphus wallichii) acclimates to high altitude environment during the withered grass period is one of the challenges in maintaining their nutrient intake. It is an important basis to study the nutritional ecology of wild large ungulates in alpine ecosystems by investigating the changes in plant communities with altitude during the withered grass period and how these changes affect the food composition of Tibetan red deer. In this study, we selected the Tibetan red deer in Sangri County, Shannan region of Tibet as the research subject. We carried out field surveys on the altitude, plant communities, and feeding traces of the Tibetan red deer in March of 2021 and 2022 during the withered grass period on the Tibetan Plateau. Detrended correspondence analysis and canonical correspondence analysis were used to study altitudinal variations in plant communities and the regularity of food composition. The results showed that during the period of withered grass, Tibetan red deer ate primarily Salix daltoniana, Rosa macrophylla var. glandulifera and Dasiphora parvifolia. S. daltoniana accounted for more than 50% of the food composition, as the main food resources for red deer in withered grass period. In the low altitude area (4100-4300 m), plant community included Caragana versicolor, R. macrophylla and Berberis temolaica, and Tibetan red deer mainly ate R. macrophylla, C. versicolor and Artemisia wellbyi. In higher altitude area (4300-4600 m), plant community consisted of Rhododendron nivale, Rhododendron fragariiflorum, and Sibiraea angustata, and Tibetan red deer mainly fed on S. daltoniana, Salix obscura, and Carex littledalei. At different altitudes, the dominant plant species were the main food of Tibetan red deer. It is suggested that the changes of plant community composition with altitude directly affected food composition of Tibetan red deer, indicating different food composition patterns with altitude gradients.

Chemical Characteristics and Source Apportionment of Biogenic Primary and Secondary Organic Aerosols in an Alpine Ecosystem of Tibetan Plateau

AbstractThe knowledge about the chemical characteristics of organic aerosols in alpines were still limited. Fifty samples were collected in an alpine site in Tibetan Plateau during May 2015 and April 2016 to measure the concentrations of sugar and biogenic secondary organic aerosol (BSOA) compounds. The annual mean concentrations of anhydrosugar, primary sugars, and sugar alcohols in Mt. Gongga were 86.6 ± 43.1, 168 ± 40.0 and 204 ± 62.9 ng/m3, respectively. All of the anhydrosugars displayed the highest concentrations in winter, followed by spring, autumn, and the lowest ones in summer, which was contributed by dense biomass burning (BB) in winter. In contrast, nearly all of the primary sugar and sugar alcohol levels peaked in summer, which might be associated with the higher rates of vegetation growth and microbial metabolic activities during the warming season. The levels of BSOA tracers also suffered from markedly seasonal variations. The sesquiterpene SOA displayed the highest level in winter (27.3 ± 16.8 ng/m3), which might be associated with the biomass burning in the surrounding regions. However, most of the species of isoprene and monoterpene SOA tracers suffered from the higher levels in summer, which was contributed by the higher biogenic volatile organic compounds (BVOC) emission and reaction rates. Based on source apportionment result, BB (26%) was the dominant contributor to sugar and BSOA species in Mt. Gongga, followed by airborne pollen (24%), plant release (19%), soil emission (13%), fungal spore (9%), and isoprene oxidation (8%). The result of this study reveals mixed contributions of BB and vegetation emission promote the formation of biogenic organic aerosols in Tibetan Plateau.

An update on the conservation status of Tibetan Argali Ovis ammon hodgsoni (Mammalia: Bovidae) in India

Mountain ungulates are important for alpine ecosystem ecology, yet are understudied, particularly in Asia. Tibetan Argali Ovis ammon hodgsoni occurs across Tibet, with Trans-Himalayan India forming the edge of its distribution. We studied their conservation status in India. We compiled published data and secondary information about the occurrence of argali. We then focused on Ladakh, the remaining stronghold of argali in India. Based on literature from Ladakh and after consulting key-informants, we delimited two major populations of argali and estimate population density and demography using the double-observer method. We found 27 studies on argali in India. Studies covered four major themes: records (n = 12), conservation (n = 7), ecology (n = 7), and evolution (n = 1), with studies increasing after 2000. Estimated argali density in Tsaba was 0.34 argali km-2 (0.32–0.40) and in Chushul-Mirpal Tso was 0.15 argali km-2 (0.12–0.30). Both populations had comparable demography including age-sex ratios. We need to urgently consider argali as a priority species for conservation in India particularly as threats—including transboundary concerns, lack of coordinated conservation across the international border, anthropogenic disturbances, competition &amp; disturbance from livestock grazing, and habitat loss—are a reality. Towards that, we delimited knowledge gaps and set robust population baselines for the two important argali populations in India. As the Tibetan Argali here co-occur with people, it will be crucial to ensure conservation is done in partnership with local communities.

Trophic classification and assessment of lake health using indexing approach and geostatistical methods for sustainable management of water resources

Abstract This study aims to analyse the spatio-temporal trends in water quality, trophic state, and organic contamination of an alpine lake in the Darjeeling Himalaya through field investigations and to portray a comprehensive picture using multivariate analysis. Analysed water parameters have shown notable seasonal variations and were within the acceptable range for inland surface water. Water quality index (WQI) and organic pollution index (OPI) values have displayed ‘poor’ to ‘heavily polluted’ status in the pre-monsoon season, with marginally better conditions during the post-monsoon studies. Trophic state indices (TSIs) values revealed ‘eutrophic to highly eutrophic’ conditions during the investigation period. The results of the PCA have depicted three major determining factors (i.e., anthropogenic contribution, geogenic or weathering, and seasonal/climatic factors) that control the overall pollution level in the lake water system. The current study can potentially be a benchmark for assessing and undertaking management and restoration measures for this nascent alpine ecosystem.

Land degradation and climate change lessened soil erodibility across a wide area of the southern Tibetan Plateau over the past 35–40 years

AbstractThe Tibetan Plateau's alpine ecosystem has been undergoing accelerated climate change and severe vegetation degradation in the past four decades, which has triggered a sharp increase in soil erosion hazards. However, the combined impacts of climate change and vegetation degradation on soil erodibility (K) across geographical and temporal scales remain unclear. Here, we present the first systematic investigation of spatio‐temporal variations in K under different land uses across the southern Tibetan Plateau over the last 35–40 years, and identify the associated driving factors based on a paired resampling campaign conducted in the 1980s and 2020, covering 148 field sites. K‐values derived for the majority of grassland (75.0%) and cropland (66.2%) sites, as well as for a substantial number of forest sites (46.7%) showed a decreasing tendency with time, with average decreases of 31%, 14%, and 5%, respectively. Changes in K were primarily (17.6%) attributed to soil erosion, but were exacerbated by climate change (8.2%). Interestingly, the declines in K resulted in significant decreases in (predicted) soil erosion rates as long as strong disturbances from climate change and human activities were absent. These findings confirm the existence of a negative feedback mechanism between soil erosion and K in most alpine ecosystems on the southern Tibetan Plateau. Our results reveal the extent to which the impact of vegetation degradation on the magnitude of K is enhanced by climate change, thereby providing new insights into the feedback between alpine ecosystems, climate change, and anthropogenic interference.