Search Results (70)

Understanding alpine plants’ survival and reproduction is crucial for their conservation in climate change. Based on 423 valid distribution points, this study utilizes the MaxEnt model to predict the potential habitat and distribution dynamics of Leontopodium nanum under both current and future climate scenarios, while clarifying the key factors that influence its distribution. The primary ecological drivers of distribution are altitude (2886.08 m–5576.14 m) and the mean temperature of the driest quarter (−6.60–1.55 °C). Currently, the suitable habitat area is approximately 520.28 × 10⁴ km², covering about 3.5% of the global land area, concentrated mainly in the Tibetan Plateau, with smaller regions across East and South Asia. Under future climate scenarios, low-emission (SSP126), suitable areas are projected to expand during the 2050s and 2070s. High-emission (SSP585), suitable areas may decrease by 50%, with a 66.07% reduction in highly suitable areas by the 2070s. The greatest losses are expected in the south-eastern Tibetan Plateau. Regarding dynamic habitat changes, by the 2050s, newly suitable areas will account for 51.09% of the current habitat, while 68.26% of existing habitat will become unsuitable. By the 2070s, newly suitable areas will rise to 71.86% of the current total, but the loss of existing areas will exceed these gains, particularly under the high-emission scenario. The centroid of suitable habitats is expected to shift northward, with migration distances ranging from 23.94 km to 342.42 km. The most significant shift is anticipated under the SSP126 scenario by the 2070s. This study offers valuable insights into the distribution dynamics of L. nanum and other alpine species under the context of climate change. From a conservation perspective, it is recommended to prioritize the protection and restoration of vegetation in key habitat patches or potential migration corridors, restrict overgrazing and infrastructure development, and maintain genetic diversity and dispersal capacity through assisted migration and population genetic monitoring when necessary. These measures aim to provide a robust scientific foundation for the comprehensive conservation and sustainable management of the grassland ecosystem on the Qinghai–Tibet Plateau. Full article

Alpine scree, a distinctive plateau ecosystem, serves as habitat for numerous rare and endangered species. However, current research does not differentiate it from desert in terms of spatial boundary, hindering biodiversity conservation and ecological monitoring efforts. Using the Tibetan Plateau as a case study, we defined the spatial boundary of alpine scree based on its surface formation process and examined its distribution and long-term evolution. The results show that in 2020, alpine scree on the Tibetan Plateau covered 73,735.34 km², 1.5 times the area of glaciers. Alpine scree is mostly distributed at elevations between 4000 and 6000 m, with a slope of approximately 30–40 degrees. Characterized by low temperature and sparse rainfall, the regions are located in the humid zone. From 1975 to 2020, the area of alpine scree initially increased before declining, with an overall decrease of 560.68 km². Climate warming was the primary driver of these changes, leading to an increase in scree from 1975 to 1995 and a decrease in scree from 1995 to 2020. Additionally, between 1975 and 2020, the Tibetan Plateau’s grasslands shifted upward by 16.47 km². This study enhances our understanding of the spatial distribution and dynamics of this unique ecosystem, alpine scree, offering new insights into climate change impacts on alpine ecosystems. Full article

The Qinghai–Tibetan Plateau (QTP), often referred to as the “Third Pole” of the world, harbors alpine grassland ecosystems that play an essential role as global carbon sinks, helping to mitigate the pace of climate change. Nonetheless, alterations in natural environmental conditions coupled with escalating human activities have disrupted the seasonal growth cycles of grasslands, thereby intensifying degradation processes. To date, the key drivers and lifecycle dynamics of Grassland Depletion across the QTP remain contentious, limiting our comprehension of its ecological repercussions and regulatory mechanisms. This study comprehensively investigates grassland degradation on the Qinghai–Tibetan Plateau, analyzing its drivers and changes in ecological suitability during the growing season. By integrating natural factors (e.g., precipitation and temperature) and anthropogenic influences (e.g., population density and grazing intensity), it examines observational data from over 160 monitoring stations collected between the 1980s and 2020. The findings reveal three distinct phases of grassland degradation: an acute degradation phase in 1990 (GDI, Grassland Degradation Index = 2.53), a partial recovery phase from 1996 to 2005 (GDI < 2.0) during which the proportion of degraded grassland decreased from 71.85% in 1990 to 51.22% in 2005, and a renewed intensification of degradation after 2006 (GDI > 2.0), with degraded grassland areas reaching 56.39% by 2020. Among the influencing variables, precipitation emerged as the most significant driver, interacting closely with anthropogenic factors such as grazing practices and population distribution. Specifically, the combined impacts of precipitation with population density, grazing pressure, and elevation were particularly notable, yielding interaction q-values of 0.796, 0.767, and 0.752, respectively. Our findings reveal that while grasslands exhibit superior carbon sink potential relative to forests, their productivity and ecological functionality are undergoing considerable declines due to the compounded effects of multiple interacting factors. Consequently, the spatial distribution of ecologically suitable zones has contracted significantly, with the remaining high-suitability regions concentrating in the “twin-star” zones of Baingoin and Zanda grasslands, areas recognized as focal points for future ecosystem preservation. Furthermore, the effects of climate change and intensifying anthropogenic activity have driven the reduction in highly suitable grassland areas, shrinking from 41,232 km² in 1990 to 24,485 km² by 2020, with projections indicating a further decrease to only 2844 km² by 2060. This study sheds light on the intricate mechanisms behind Grassland Depletion, providing essential guidance for conservation efforts and ecological restoration on the QTP. Moreover, it offers theoretical underpinnings to support China’s carbon neutrality and peak carbon emission goals. Full article

Under the pressures of global climate change, the sustainable management of plant resources in alpine gorge regions faces severe challenges. P. aquilinum var. latiusculum is widely harvested and utilized by residents in the upper reaches of the Dadu River–Min River basin due to its high edible and medicinal value. This study employed ensemble models to simulate the potential distribution of P. aquilinum var. latiusculum in this region, predicting the impacts of future climate change on its distribution, the centroid migration of suitable habitats, and niche dynamics. A production dynamics model was also constructed to identify current and future potential cultivation areas by integrating ecological suitability and nutritional component synergies. The results show that current high-suitability areas and core cultivation zones of P. aquilinum var. latiusculum are predominantly distributed in patchy, fragmented patterns across the Wenchuan, Li, Mao, Luding, and Xiaojin Counties and Kangding City. Under climate change, the “mountain-top trap effect” drives a significant increase in high-suitability areas and core cultivation zones, while moderate-to-low-suitability areas and marginal cultivation zones decrease substantially. Meanwhile, suitable habitats and cultivation areas exhibit a northward migration trend toward higher latitudes. The most significant changes in suitable area and cultivation zone extent, as well as the most pronounced niche shifts, occur under high-emission climate scenarios. This research facilitates the development of suitability-based management strategies for P. aquilinum var. latiusculum in the study region and provides scientific references for the sustainable utilization of montane plant resources in the face of climate change. Full article

Under global climate change, sustainable management of plant resources in alpine canyon regions faces severe challenges. M. esculenta, highly valued for its edible and medicinal properties, is widely harvested for consumption by residents in the upper Dadu River–Minjiang River region. This study employs ensemble models to simulate the potential distribution of M. esculenta in this region, predicting the impacts of future climate change on its distribution, centroid migration of suitable habitats, and niche dynamics. Additionally, a production dynamics model integrating ecological suitability and nutritional components was developed to delineate current and future potential cultivation zones for M. esculenta. The results indicate that current high-suitability areas and core cultivation zones of M. esculenta are predominantly distributed in a patchy and fragmented pattern. The high-suitability habitats in the upper Dadu River–Minjiang River region have three distribution centers: the largest spans southern Danba County, southern Jinchuan County, and northeastern Kangding City, while the other two are located in northeastern Li County, southwestern Aba County, and northwestern Ma’erkang City, with sporadic distributions in Heishui County, Maoxian County, and Wenchuan County. First-level cultivation areas are primarily concentrated in Kangding City, Danba County, Ma’erkang City, Li County, and surrounding regions. Under climate change, low-suitability areas and third-level cultivation zones for M. esculenta in the region have increased significantly, while high- and medium-suitability areas, along with first- and second-level cultivation zones, have decreased notably. Concurrently, suitable habitats and cultivation zones exhibit a migration trend toward higher northern latitudes. The most pronounced changes in suitable areas and cultivation zones, as well as the largest niche migration, occur under the high-emission climate scenario. This study facilitates the formulation of suitability-based management strategies for M. esculenta in the upper Dadu River–Minjiang River region and provides a scientific reference for the sustainable utilization of mountain plant resources under climate change. Full article

The temporal stability of alpine plant α-diversity remains poorly understood, constraining predictions of biodiversity dynamics. Here, this study examined spatiotemporal patterns in the temporal stability of plant α-diversity (species richness, Shannon, Simpson, and Pielou) across the Tibetan grasslands from 2000 to 2020. The temporal stability of plant α-diversity was more sensitive to changes in elevation compared to longitude and latitude. The greater the temporal stability of a plant species’ Shannon, the higher its rate of increase under the combined effects of climate change and human activities. The spatial average temporal stability of plant α-diversity declined by 8.83–16.40% across all the grasslands of the Qinghai-Xizang Plateau, while 39.34–43.77% of the region exhibited increasing trends under the combined effects of climate change and human activities. Climate change and human activities dominated 44.12–48.71% and 51.24–55.84% of grassland areas of the change of temporal stability of plant α-diversity, respectively. Radiation variability exerted some exclusive effects on the temporal stability of plant α-diversity. The relative change in plant α-diversity did not exhibit simple linear relationships with the relative change in its temporal stability. Therefore, climate change and human activities resulted in the spatial heterogenization of the temporal stability of plant α-diversity. While the overall temporal stability of plant α-diversity declined, some areas experienced local increases. Human activities drove changes in temporal stability across a broader area than climate change. In addition to climate warming and precipitation changes, attention should also be paid to the impact of radiation variability on the temporal stability of plant α-diversity. The relationships between plant α-diversity and its temporal stability were not always characterized by a trade-off or synergy. In future grassland biodiversity conservation efforts, it is essential to consider the potential influence of global dimming on the temporal stability of plant α-diversity. Simultaneously monitoring both α-diversity and its temporal stability, especially in areas where both are declining, should be a priority. Full article

The Qinghai–Tibet Plateau is a key region for biodiversity conservation, where alpine grasslands are ecologically important. While previous studies have mainly addressed vegetation, ecosystem processes, and soil microbes, phyllosphere microorganisms are essential for nutrient cycling, plant health, and stress tolerance. However, their communities remain poorly understood compared to those in soil. The relative influence of host identity and environmental conditions on shaping phyllosphere microbial diversity and community assembly remains uncertain. In this study, we characterized phyllosphere bacterial and fungal communities of the phyllosphere at two alpine steppe sites with similar vegetation but climatic conditions: the Qilian Mountains (QLM) and the Qinghai Lake region (LQS). At both sites, Cyanobacteriota and Ascomycota were the predominant bacterial and fungal taxa, respectively. Microbial α-diversity did not differ significantly between the two regions, implying that host-associated mechanisms may stabilize within-site diversity. In contrast, β-diversity exhibited clear spatial differentiation. In QLM, bacterial β-diversity was significantly correlated with mean annual precipitation, while fungal α- and β-diversity were associated with soil nutrient levels (including nitrate, ammonium, available potassium, and phosphorus) and vegetation coverage. At LQS, the β-diversity of both bacterial and fungal communities was strongly influenced by soil electrical conductivity, and fungal communities were further shaped by vegetation cover. Community assembly processes were predominantly stochastic at both sites, although deterministic patterns were more pronounced in QLM. Variability in moisture availability contributed to random bacterial assembly at LQS, while increased environmental heterogeneity promoted deterministic assembly in fungal communities. The elevated diversity of microbes and plants in QLM also reinforced deterministic processes. Overall, our findings support a host–environment interaction hypothesis, indicating that host factors primarily govern α-diversity, while climatic and soil-related variables have stronger effects on β-diversity and microbial assembly dynamics. These insights advance our understanding of how phyllosphere microbial communities may respond to environmental change in alpine ecosystems. Full article

Vegetation change profoundly influences ecosystem sustainability and human activities, with solar radiation serving as a primary driver. However, the effects of surface radiative forcing (SRF) and related factors on vegetation dynamics remain poorly understood. The Tibetan Plateau, a climate-sensitive region, offers a unique context to investigate these relationships. This study analyzes the association between vegetation greening and SRF on the Tibetan Plateau from 1982 to 2021. Using forecast albedo (FAL) and surface solar radiation downwards (SSRD), we calculated SRF and explored its correlation with the Normalized Difference Vegetation Index (NDVI) and land cover data. The results indicate a gradual increase in growing-season NDVI, suggesting vegetation greening. Both FAL and SSRD exhibit decreasing trends, yet neither shows a statistically significant correlation with NDVI. The correlations between FAL/SSRD and NDVI weaken with increasing altitude, declining by 0.035 × 10⁻¹ per 500 m and 0.021 × 10⁻¹ per 500 m, respectively. Among vegetation types, FAL correlates most strongly with shrubland NDVI and weakest with forest NDVI, while SSRD demonstrates the highest correlation with grassland NDVI and lowest with forest NDVI. The impact of SRF on NDVI changes is evident in 52.881% of the plateau, showing a positive correlation between SRF and ΔNDVI, compared to 39.589% for SSRD and ΔNDVI. This research enhances the understanding of vegetation responses to FAL, SSRD, and SRF, providing a scientific basis for ecological conservation and climate adaptation strategies, and also emphasizes radiation–vegetation feedback, providing guidance for conservation strategies in other alpine ecosystems globally, such as the Andes and Alps, where elevation gradients and vegetation-type-specific responses to radiative forcing may similarly govern ecological outcomes. Full article

Argentina anserina (Rosaceae), a perennial herb, forms enlarged tuberous roots (commonly referred to as “ginseng fruit”) exclusively in the Qinghai–Tibet Plateau, making it a unique medicinal and edible plant resource in this region. The upper reaches of the Dadu River and Minjiang River are one of its primary production areas in China. This study employs an ensemble model to simulate the potential distribution of A. anserina in this region, predicting the impacts of future climate change on its distribution, ecological niche, and centroid migration patterns. Additionally, a cultivation productivity evaluation model integrating ecological suitability and nutritional components was developed to delineate potential cultivation areas. Results indicate that high-suitability habitats span 0.37 × 10⁴ km² (7.39% of the total suitable area), exhibiting a patchy and fragmented distribution in Aba County, Rangtang County, Jiuzhi County, and Banma County. Core cultivation areas cover 3.78 × 10⁴ km², distributed across Aba County, Rangtang County, Jiuzhi County, Seda County, Banma County, Hongyuan County, and Markam City. Under future climate scenarios, the suitable distribution area of A. anserina will gradually decline with rising temperatures, migrating to higher-latitude northern regions, accompanied by increased niche migration. By the 2090s under the SSP5-8.5 scenario, the centroid demonstrates the largest migration amplitude, with high-suitability habitats showing a “collapsing” polarization pattern and near-complete niche separation from the previous period, indicating significant changes. Collectively, these results provide a theoretical basis for the sustainable utilization of A. anserina in the upper Dadu River and Minjiang River basin. Full article

The Dolomites (European Alps) are a UNESCO World Heritage Site known to harbor distinctive communities of carabid beetles adapted to high-altitude environments, whose composition is shaped mainly by landform and habitat type. We aimed to assess the conservation priority of carabid beetle communities in the Brenta mountain group (Italy). We used the Index of Natural Value (INV), based on the relative frequencies and abundances of highly specialized Alpine species, as a proxy of the sensitivity to disturbance, and, thus, to the vulnerability of the carabid beetle communities to extinction. We used information on Natura 2000 habitat cover to produce a map for identifying areas of the Brenta Dolomites inhabited by the carabid beetle communities most relevant for conservation. We also report on the main differences in terms of species composition between the investigated communities. We found a positive correlation between vulnerability and altitude. Specifically, the most vulnerable communities were recorded in high-altitude habitat types (limestone cliffs and pavements, calcareous and calcschist screes, and alpine calcareous grasslands). Alkaline fens resulted in having the least vulnerable community, while those in all other habitats (bush and forests) were found to have intermediate levels of vulnerability. Full article

Accurate identification of mattic epipedon degradation is critically important for addressing ecological issues such as the weakening of alpine grassland carbon sink capacity and reduced soil and water conservation. However, efficient and rapid methods for its detection remain limited. This study aimed to clarify the hyperspectral response mechanisms of mattic epipedon degradation and, based on hyperspectral technology, to construct models for identifying degraded mattic epipedon and screen preprocessing methods suitable for different moisture conditions. The results showed the following: (1) The XGBoost model with preprocessing using multiplicative scatter correction combined with second derivative transformation (MSC+SD) performed best, achieving an identification accuracy and Kappa coefficient of 0.85 and 0.82, respectively. The characteristic bands were concentrated in the visible light range (446–450 nm) and short-wave infrared range (2134 nm, 2267–2269 nm), which are closely related to the spectral responses of organic carbon and mineral components. (2) Spectral reflectance was significantly negatively correlated with moisture content, and model accuracy decreased as moisture content increased. (3) After correction using the EPO algorithm, the model accuracy for the high-moisture group improved by 13.2–16.7%, whereas that for the low-moisture group (<15%) decreased by 7.5%, verifying 15% moisture content as the critical threshold for water interference. This study elucidated the impact mechanism of moisture on the hyperspectral characteristics of the mattic epipedon. The established MSC+SD-XGBoost model adapts to varying moisture conditions, providing technical support for the rapid monitoring of mattic epipedon degradation and holding significant practical value for carbon management in alpine ecosystems. Full article

Against the background of climate change, grazing accelerates the warming and drying processes in grasslands. There is a relatively clear temperature and humidity difference between grassland used for grazing and grassland that has been excluded from grazing practices. This paper asks whether temperature and humidity differences affect plant roots and cold resistance. Representative plants from an alpine meadow on the eastern margin of the Qinghai–Tibetan Plateau were selected under grazing exclusion and grazing conditions. Dominant plants within and outside of an alpine meadow enclosed for 10 years in the study area were selected as the research objects to study the root morphology and physiological indices of the cold resistance of these plants. The results showed that (1) grazing exclusion (GE) was beneficial for soil temperature and water retention, reduced soil pH, and increased soil nutrient content. Under grazing exclusion conditions, all plant root morphological traits, except root tissue density, increased compared with those under grazing grassland (FG) conditions. Grazed plants adopted resource acquisition strategies, while grazing exclusion plants adopted resource conservation strategies. (2) The changes in the physiological indices of cold resistance in different years and grazing treatments were different. In 2023, the superoxide dismutase (SOD) activity and soluble protein content in GE conditions were significantly lower than those in FG conditions, while the peroxidase (POD) activity was significantly higher than that under FG conditions. The activity of catalase (CAT) in the GE plot was significantly lower than that in the FG plot in 2024. The cold resistance of Gramineae species was lower than that of non-Gramineae plants. A redundancy analysis (RDA) of plant root morphological traits, soil properties, and cold resistance showed that root length and soil pH were the most important factors affecting plant cold resistance. We concluded that grazing exclusion is conducive to plant root growth, but also acidifies the soil and reduces plant cold resistance. Full article

Ecosystem services (ESs) are fundamental to human well-being, yet the capacity of ecosystems to provide ESs is increasingly altered by anthropogenic climate and land use changes. Understanding how climate change and land use change impact ecosystem service (ES) dynamics is critical for promoting sustainable region development in ecologically sensitive regions. Using the InVEST model and a scenario-based framework, this study assesses the relative contributions of climate and land use changes to water yield, soil conservation, carbon sequestration, and habitat quality in the upper Minjiang River basin, China from 1990 to 2020 and projects ES changes under future climate and land use scenarios for 2050. Our results show that climate change played a dominant role in increasing water yield and soil conservation services, particularly after 2000, while land use changes enhance carbon sequestration and habitat quality. Although forest expansion contributed positively to carbon storage and erosion control, the loss of grassland and increased construction land reduced habitat quality and intensified erosion risks in some areas. Scenario simulations for 2050 demonstrate that the ecological protection scenario yields the most balanced improvements in all four ESs. These findings highlight the distinct roles of climate and land use changes in shaping ecosystem service provision and offer a scientific basis for promoting the sustainable regional environment in alpine regions under changing climate and land use. Full article

Aboveground biomass (AGB) is a key parameter for studying the carbon cycle, evaluating grassland growth, and assessing the grass–livestock balance. In this study, we established an optimal inversion model for alpine grassland AGB and estimated the growing-season (July–September) AGB from 2018 to 2022 based on field survey data and remote sensing data. We aimed to analyze the spatiotemporal dynamics of AGB in alpine grasslands and its response mechanisms to hydrothermal factors, as well as to explore the indirect impacts of changes in human activities during the COVID-19 pandemic on the grassland ecosystem. The results showed the following: (1) Alpine grassland AGB was high in the southwest and low in the northeast of the studied area, initially increasing and then decreasing over time. This pattern was largely consistent with the spatial distribution and interannual variations in precipitation and temperature, with a significant positive correlation being observed between precipitation and AGB, indicating that hydrothermal factors are key drivers of grassland AGB dynamics. (2) The grasslands demonstrated a trend of slight decrease in AGB overall, with some local areas showing a slight increase. Compared with before 2018, grasslands showed a gradual recovery trend, which may be related to grazing policies and conservation management measures. (3) An increase in grazing intensity in local areas decreased grassland AGB and vice versa, indicating that the restrictive measures led to changes in grazing intensity, which indirectly affected grassland AGB during the pandemic. This study reveals the general patterns of hydrothermal factors’ influence on alpine grassland AGB dynamics during the pre-, mid-, and post-COVID-19-pandemic periods, providing a scientific basis for formulating sustainable grassland management strategies. Full article

The Shiquan River National Wetland Park in Tibet is an integrated high-elevation wetland ecosystem. This wetland park also serves as a demonstration site for international river conservation and the ‘conservation–utilization–sustainable enhancement’ of wetland resources in alpine desert zones. This study supplements the research on bird community structure and ecological function to fill the gap in basic data on birds in the Shiquan River National Wetland Park. From May 2023 to October 2024, a sampling point method was used to conduct four systematic surveys during the breeding and non-breeding periods of birds in four habitats—grass land, marsh land, bare land, and water bodies—in the Shiquan River National Wetland Park to explore the effects of different habitat types on bird communities from the perspective of species and functional diversity. A total of 56 bird species, representing 23 families and 11 orders, were documented in this survey. Species diversity was highest in the marsh habitat during the breeding season, followed sequentially by grassland, bare land, and water bodies, with consistent results in the non-breeding period. The functional richness (FRic) results revealed a pattern of marsh land > grass land > bare land > water bodies, indicating that birds utilized the ecological space within the marsh habitat to the greatest extent. The functional differentiation (FDiv) results followed a pattern of bare land > water bodies > grass land > marsh land, suggesting stronger niche complementarity and weaker competition in bare ground habitats. Finally, the functional dispersion (FDis) results demonstrated a pattern of grass land > marsh land > bare land > water bodies, indicating a greater number of species with similar functional traits in grass habitats. This study addresses the research gap concerning bird communities in the Shiquan River National Wetland Park through the lens of both species and functional diversity, thereby providing a scientific foundation and critical support for the conservation of avian biodiversity in the Shiquan River Basin and high-elevation regions. Full article