Anthropogenic land use constitutes a key driver of land cover change, exerting profound impacts on terrestrial carbon/water cycles and ecosystems across global to regional scales. Consequently, long-term land cover datasets serve as fundamental data infrastructure for ecological effect assessment and paleoclimate modeling. Considering the dominant role of historical anthropogenic disturbances in vegetation change across the Hehuang Valley, we developed a 1 km × 1 km potential vegetation prior to land reclamation map through integrating remotely sensed land-use patterns with Random Forest-modeled vegetation predictions. Then, we derived changes in forest and grassland areas and their spatial patterns over the past two millennia by subtracting the spatially explicit cropland cover for six agricultural expansion stages. Finally, we compared our results with representative historical LUCC datasets. The main conclusions are as follows: (1) The potential vegetation of the Hehuang Valley was predominantly grassland, with forest occurring as a patchy and linear mosaic. Grassland and forest covered approximately 2.6 × 104 km2 and 0.7 × 104 km2, respectively. (2) Over the past two millennia, during the Han (202 BCE–220 CE), Tang (618–907 CE), Song (960–1279 CE), Ming (1368–1644 CE), and Qing (1644–1912 CE) dynasties, as well as the Republic of China period (1912–1949 CE), cropland reclamation reduced forest and grassland cover by 6% and 18%, respectively. Forest area decreased by 23.58–100.03 km2, while grassland area decreased by 310.72–1513.05 km2 across these periods. Grassland reduction was concentrated in valleys, whereas forest reduction was spatially scattered but locally intensive. These findings highlight the need to promote sustainable cropland development through technological innovation, improved management, and agricultural specialization rather than ecosystem conversion. (3) Compared with the HYDE 3.2 dataset and a national-scale reconstruction dataset, our framework better reflects the regional characteristics of the Hehuang Valley and provides a more detailed reconstruction of long-term forest and grassland changes.

The Liujiaxia-Manglaxia segment of the upper Yellow River, located at the northeastern margin of the Tibetan Plateau, has experienced significant clustering of giant landslides since the Holocene, acting as a critical surface process shaping the regional geomorphology. While tectonic activity and climate change are recognized as primary drivers, the coupling mechanisms triggering landslide clustering during climate transitions remain unclear. This study compiled an inventory of 14 giant Holocene landslides in the upper Yellow River by integrating literature review, field investigation, and remote sensing. We calculated the distance between landslides and faults using ArcGIS, and inferred triggering factors based on deposit characteristics and mechanical deformation modes. Finally, by integrating high-resolution paleoclimate records, we investigated the coupled tectonic-climatic driving mechanisms behind landslide clustering. Since the Holocene, giant landslide clusters in the Liujiaxia-Manglaxia section of the Upper Yellow River have exhibited pronounced spatiotemporal clustering. Temporally, these events occurred primarily across four distinct phases: 10–8 ka B.P., 5.0–4.5 ka B.P., 4–3.7 ka B.P., and the modern era, with the 5.0–4.5 ka B.P. interval representing the most intensive period. Spatially, the landslides are predominantly distributed within the Jishixia Canyon and along the right bank (looking downstream) and concave banks of the Yellow River. The transitional phase from arid to humid climate conditions is identified as the critical stage for these giant landslide clusters. During this period, intensified precipitation served as a primary driver, while the lag effect of vegetation response and cumulative slope damage induced by earthquakes during preceding arid intervals also played significant roles in the clustering phenomenon. The transition from a dry to a wet climate promoted the clustering of giant landslides through the combined effects of increased precipitation, the lag effect of vegetation change, and tectonic activity.

The source area of the Yellow River (SAYR) is a critically important cryospheric region highly sensitive to climate warming. However, capturing fine-scale thawing–freezing dynamics remains challenging due to the region’s rugged topography and sparse observational networks. In this study, we developed a 1-km, 40-year (1981–2020) dataset of surface temperatures and thawing–freezing indices by applying month-specific topographic corrections to ERA5-Land reanalysis data. Validation against independent station observations yielded a root mean square error (RMSE) of 1.49°C, and uncertainty assessments demonstrate that the monthly-derived indices capture interannual trends with high consistency (R2 > 0.97). Over the past four decades, regional freezing indices have significantly decreased, while thawing indices have increased, resulting in an extension of the average thawing duration by 1.17 days per decade. Furthermore, a regime shift detected in 2005 prolonged the annual thawing duration by 14.8 days, extending the unfrozen soil period and potentially enhancing moisture infiltration into the subsurface. Spatially, this thawing intensification is most pronounced in the southeastern valleys, whereas changes in the thermal regime over the northwestern and central highlands indicate intensified ground warming, which is likely associated with permafrost degradation and active-layer deepening. Overall, this high-resolution dataset offers an improved representation of surface thermal processes compared to traditional air-temperature-based proxies, providing valuable support for climate adaptation and infrastructure planning in this critical headwater region.

Against the backdrop of global warming,the risk of river and lake flood disasters along plateau railways is increasing.The Qinghai-Xizang Railway is the world's longest railway traversing a plateau region.A comprehensive hazard assessment of river and lake flood disasters along the route was conducted after identifying hazard points within a 50-km buffer zone of the railway.The main findings were as follows.(1)The hazard levels for river density,potential flood points of rivers,lake breaching,and waterlogging,in the"relatively high"to"high"classes,accounted for 35.64％,24.84％,10.88％,and 18.18％of the study area,respectively.(2)The comprehensive hazard due to river flood disasters along the rail-way was mainly distributed in the Nachitai-Lhasa section.High hazards due to lake breach-ing and waterlogging were concentrated in the Nachitai-Anduo section.(3)In terms of the comprehensive hazard of river and lake flood disasters,sections with"relatively high"to"high"hazard levels accounted for 22.18％of the total area."High"hazard areas were con-centrated in the Nachitai-Anduo section.With the intensification of global warming,flood risks along high-altitude railway lines are expected to escalate substantially.In particular,the risks arising from upstream or distant glacial lake outburst floods,river capture,and lake expansion should not be underestimated.

Understanding how the internal structure of precipitation events evolves and responds to antecedent thermal conditions is essential for revealing the mechanisms of extreme precipitation in plateau-margin mountainous regions. Using hourly precipitation and air temperature data from 14 national reference meteorological stations in the Hehuang Valley during the warm seasons (May-September) of 2015-2024, this study constructed an event-based precipitation database and introduced the inter-event maximum temperature (T-max_inter) as an indicator of antecedent thermal accumulation. The Theil-Sen slope estimator, Mann-Kendall trend test, K-means clustering, and binary logistic regression were applied to examine changes in precipitation-event structure and their nonlinear response to antecedent high temperature. Results show that warm-season precipitation was characterized by fluctuating frequency but increasing intensity. Precipitation events were classified into three types-uniform, front-peaked, and rear-peaked-with the proportion of uniform events decreasing and the proportions of front-peaked and rear-peaked events increasing. T-max_inter was significantly positively associated with extreme precipitation occurrence: for every 1 degrees C increase in T-max_inter, the odds of extreme precipitation increased by 13.4% (OR = 1.134, 95% CI: 1.10-1.17, p < 0.001). These findings provide a reference for extreme precipitation risk identification and disaster prevention in plateau-margin mountainous areas.

This dataset was developed based on climate projection data under three Shared Socioeconomic Pathways(SSP126,SSP245,and SSP585)from the Coupled Model Intercomparison Project Phase 6(CMIP6),combined with historical temperature,precipitation,and NDVI observations with a spatial resolution of 1 km across the Qinghai-Tibet Plateau from 2000 to 2020.A multiple linear regression model was employed to characterize the relationship between climate factors and vegetation responses,enabling the generation of annual NDVI predictions from 2025 to 2100.To improve spatial accuracy,the original climate simulation data were spatially downscaled using bias correction and bilinear interpolation techniques.Modeling procedures,including NDVI simulation,error control,and regional masking under different scenarios,were implemented in MATLAB.The dataset covers the entire Qinghai-Tibet Plateau,over a 76-year period,with a spatial resolution of 1 km.It consists of 228 GeoTIFF raster files with a total volume of 2.43 GB.Model performance was evaluated using the coefficient of determination(R2)and root mean square error(RMSE).Across all scenarios,R2 values exceeded 0.72 and RMSE values remained below 0.13,indicating reliable data quality.This dataset features multi-scenario comparability,long-term temporal continuity,and high spatial detail,providing valuable support for a wide range of ecological and climate-related studies,including ecosystem service simulation,regional carbon sink estimation,and vegetation dynamics,with broad application potential.

In the context of global warming, extreme precipitation on the Qinghai-Tibet Plateau has intensified significantly. Understanding the internal structure of precipitation events and their response to rising temperatures is crucial for elucidating these intensification mechanisms. Focusing on the Hehuang Valley, this study constructed an event-scale dataset using hourly observations from 15 meteorological stations (2015–2024), introducing “Inter-event Maximum Temperature” as a key thermal driver. By integrating clustering, trend tests, and logistic regression, we analyzed the spatiotemporal evolution of precipitation extremes. Results indicate that: (1) regional precipitation exhibits a pattern of fluctuating frequency but increasing intensity; (2) the proportion of uniform precipitation has decreased while non-uniform types, especially rear-peak events, have increased significantly; (3) spatial heterogeneity is strongly influenced by topography, with extreme precipitation concentrated on windward slopes and in valley contractions;(4) Inter-event maximum temperature exerts a significant non-linear positive effect, where a 1°C increase raises the odds ratio for extreme precipitation occurrence by approximately 13.4%. These results confirm that antecedent thermal accumulation enhances extremes by increasing atmospheric water-holding capacity and convective instability. While decadal-scale uncertainties remain due to the limited 10-year data span, these findings provide a scientific basis for disaster prevention and water resource management in high-altitude basins.

Snow disasters constitute a major natural hazard in Northwestern China, where heavy snowfall, blowing snow, and avalanches pose significant threats to infrastructure and socioeconomic activities. A scientific assessment of regional snow disaster risk is therefore critical for disaster prevention, spatial planning, and sustainable development. This study integrates multi-source remote sensing and geographic data to develop a comprehensive risk assessment method. By entropy weight method (EWM), we construct an assessment model that quantifies the combined hazard potential of heavy snowfall, blowing snow, and avalanches. The results reveal a significant spatial correlation among the three primary hazard types. The average potential hazard intensity of heavy snowfall is greater than that of blowing snow, which in turn exceeds that of avalanches. Spatially, the comprehensive snow disaster risk is most severe in the Altai Mountains, the Ili River valley, and the Tacheng region. A moderate-to-high risk level is distributed across the southwestern valleys and the foothills of the northeastern mountains. In contrast, the lowest risk areas are concentrated in certain interior valleys and the leeward slopes of the Junggar Basin. The resulting regional risk zoning was evaluated using receiver operating characteristic (ROC) curve analysis and disaster records. The model achieved an area under the receiver operating characteristic curve (AUC) of 0.871 and an overall accuracy of 84.3%, indicating good spatial discrimination between high- and low-risk zones. These metrics support the application of the framework to regional snow disaster risk assessment.

To reveal the spatiotemporal variations in near-surface oxygen content during the growing season across different altitudinal gradients in Qinghai Province and to deepen the understanding of oxygen cycling in plateau ecosystems, this study analyzed daily observations from 12 monitoring stations spanning three elevation ranges (1500–2500 m, 2500–3500 m, and 3500–4500 m) during the 2022–2023 growing seasons (March–July). The Mann–Kendall test was employed to detect temporal trends, variability indices such as standard deviation and coefficient of variation were used to quantify fluctuation intensity, kernel density estimation (KDE) was applied to characterize distributional features, and the Kruskal–Wallis test was conducted to assess statistical significance. The results indicate that: (1) oxygen content showed a significant increasing trend at all three altitudinal gradients, with the strongest rise at low elevations and the weakest at high elevations; (2) fluctuation intensity exhibited clear spatial heterogeneity, with the most pronounced variability in summer at low elevations, a distinct peak in June at mid-elevations, and overall stability at high elevations; and (3) KDE analysis revealed a broader distribution and higher frequency of extreme oxygen values at low elevations, while mid- and high-elevations displayed more concentrated distributions. Both the Kruskal–Wallis test and post hoc comparisons confirmed highly significant differences among the three elevation ranges. These findings demonstrate that elevation is a key factor influencing the spatiotemporal distribution of near-surface oxygen content during the growing season in Qinghai Province. Differences are not only evident in absolute oxygen levels but also in fluctuation intensity and distributional characteristics. This study provides empirical evidence for understanding oxygen variability mechanisms on the plateau and offers theoretical and practical references for ecological management and health risk prevention in high-altitude regions.

The Qinghai–Tibetan Plateau is one of the least hospitable areas for agriculture. Nevertheless, humans have long conducted agricultural activities on the Qinghai–Tibetan Plateau, although the amount and extent of historical cropland remains unclear. We focused on the Qinghai–Tibetan Plateau and selected the Tubo Kingdom (AD 633–842) and the Yuan Dynasty (AD 1271–1368) as study periods to explore the human–Earth relationship in high–cold plateau areas. First, we estimated the population size of the Tubo Kingdom and extracted the household data of the Yuan Dynasty from historical literature. Then, to estimate the total cropland area of the Qinghai–Tibetan Plateau, we proposed a comprehensive method for cropland estimation due to the specificity of historical literature. Finally, we obtained the Qinghai–Tibetan Plateau cropland cover by allocating the cropland area into 5'×5' grids. Finally, the main findings were as follows. (1) Total cropland area was 3.87 × 103 and 1.34 × 103 km2 during the Tubo Kingdom and Yuan Dynasty, respectively. (2) In the Tubo Kingdom, the fraction of cropland was highest in the Three-River Region (Yarlung Zangbo River, Lhasa River, and Nianchu River), with a gradual decline in the northeastward direction. During the Yuan Dynasty, cropland was concentrated in the Three-River Region and scattered in the valleys of the Nujiang and Lancang rivers. (3) Our reconstructions were highly consistent with regional development history, and addressed the gap in current global land cover datasets regarding the Qinghai–Tibetan Plateau. Thus, this study is vital to support prediction and simulation of regional and global environmental change.

With the increasing volatility and extremity of global climate change, the frequency, intensity, and associated impacts of compound extreme climate events have escalated substantially. To investigate the temporal trends and characteristics of such events, we identified compound extreme climate events in the Huangshui River Basin, located in the northeastern Qinghai–Tibet Plateau, using daily mean temperature and precipitation records from eight meteorological stations. Compound warm–wet, warm–dry, cold–wet, and cold–dry events from 1960 to 2022 were detected based on cumulative distribution functions, and their long-term trends and intensity structures were examined. The results show that: (1) Warm–dry events dominate the basin, with an average annual frequency of 32.84 days per year, occurring frequently across all seasons; cold–dry events rank second (22.38 days per year) and are particularly frequent in winter. (2) Warm–dry events are highly concentrated in the river valley region (e.g., Minhe station), whereas cold–dry and warm–wet events mainly occur in the low-mountain areas (e.g., Huangyuan and Datong). (3) From 1960 to 2022, warm–dry and warm–wet events exhibit a highly significant increasing trend (p < 0.001), cold–dry events show a significant decreasing trend, and cold–wet events display no statistically significant trend. (4) In terms of intensity, all four types of compound events—warm–wet, warm–dry, cold–wet, and cold–dry—are dominated by weak to moderate grades. Overall, the basin is undergoing a compound-risk transition from historically “cold–dry dominated” conditions toward a regime characterized by “warm–dry predominance with emerging warm–wet events.” By identifying compound extreme climate events and analyzing their spatiotemporal variability and intensity characteristics, this study provides scientific support for disaster prevention, daily management, and risk mitigation in climate-sensitive regions. It also offers a useful reference for developing strategies to address compound extreme events induced by climate change and for implementing regional risk-prevention measures.

Global warming has intensified freeze–thaw activity in high-latitude and high-altitude regions; along the western sector of the farming–pastoral ecotone in northern China, pronounced seasonal freeze–thaw cycles now pose a severe threat to land resources. This study aims to quantitatively reveal the spatial differentiation patterns of freeze–thaw erosion in the western segment and its influencing factors. This study begins with the fundamental concepts of freeze–thaw erosion, grounded in soil mechanical fragmentation and gravitational migration. Critical slope is used as the identification criterion to delineate freeze–thaw erosion zones. Building upon this foundation, a Random Forest model is employed to calculate the weighting factors influencing freeze–thaw erosion in the western segment of the northern agro-pastoral transition zone, thereby constructing a graded evaluation model for freeze–thaw erosion intensity. Results indicate the following: (1) Freeze–thaw erosion exhibits no discernible distribution pattern in the western segment, appearing scattered, while non-freeze–thaw erosion is primarily concentrated in the northern region. (2) Freeze–thaw erosion intensity ranges from 1.48 to 4.58 in the western segment. The total area of the study region is 151,000 km2, the affected area spans 122,400 km2, accounting for 81.11% of the total regional area. (3) Regionally, the Hehuang Valley exhibits predominantly strong and severe erosion, while the northern Loess Plateau shows mostly slight erosion. The southern Loess Plateau features light and moderate erosion with scattered instances of severe erosion. (4) Vegetation coverage and soil moisture are the primary contributing factors to freeze–thaw erosion. This study proposes, for the first time, a method that couples annual freeze–thaw day cycles with a critical slope threshold to delineate freeze–thaw erosion zones, demonstrating broad applicability. It systematically uncovers the spatial heterogeneity of freeze–thaw erosion in the western sector, substantially advancing scientific understanding of the process and providing a theoretical basis for its targeted management.

Freezing and thawing have important effects on soil erosion, especially in the western part of the agricultural and pastoral intertwined belt in northern China where seasonal freezing and thawing are significant. In this study, the effects of water content and the number of freeze-thaw cycles on the shear strength characteristics of soil were investigated by freeze-thaw cycle test and straight shear test using loessial soil, sierozem, and chernozem in this region. The results indicate that: (1) The soil shear strength decreases first and then stabilizes with the increase of freeze-thaw cycles and decreases with the increase of water content. After 10 freeze-thaw cycles, the shear strength of loessial soil, sierozem, and chernozem with 10% water content decreases by an average of 7.92%, 8.23%, and 12.24%, respectively. (2) Freeze-thaw cycles cause the soil's cohesion to decrease initially and then stabilize, while the increase in water content weakens this trend. After 10 freeze-thaw cycles, the cohesion of loessial soil, sierozem, and chernozem with 10% water content decreases by an average of 33.33%, 31.25%, and 16.39%, respectively. (3) Freeze-thaw cycles cause varying changes in the internal friction angle of the three soils, while an increase in water content reduces the internal friction angle. When the water content increases from 10 to 30%, the internal friction angle of loessial soil, sierozem, and chernozem decreases by an average of 7.14%, 8.79%, and 10.99%, respectively. These findings are of significant importance for deepening the understanding of the mechanisms underlying soil erosion and formulating targeted soil conservation measures.

The intensifying global warming and the increasing frequency of extreme weather events have created an urgent need for targeted resilience building in mountainous villages. This study focuses on three typical villages in the Hengduan Mountains region. From the perspective of individual villagers, a disaster resilience evaluation index system was constructed, encompassing four dimensions: disaster prevention capacity, disaster resistance capacity, disaster relief capacity, and recovery capacity. Using the entropy method and a village disaster resilience assessment model, the disaster resilience levels of each village were quantitatively evaluated. The results indicate the following: (1) Disaster resistance capacity is the key factor constraining the disaster resilience level of mountain villages. (2) The overall disaster resilience of mountain villages is at a medium level, with minor differences among villages. (3) Significant disparities exist in capacity dimensions across villages: Qina Village demonstrates the strongest disaster resistance capacity, while Xiamachang Village excels in disaster prevention capacity but shows relative weakness in recovery capacity. (4) Household material endowment has a significant positive impact on disaster prevention, resistance, relief, and recovery capacities, while individual self-rescue capability and individual–government collaboration capacity also significantly enhance disaster prevention, resistance, and relief capacities. We propose the following: Leveraging the rural revitalization strategy as a pivotal point, this approach promotes the diversified development of the village economy. It facilitates the increase in villagers’ income through the implementation of employment skill training programs, thereby strengthening household material foundations to enhance individual disaster resilience. By relying on the mass monitoring and mass prevention mechanism and a disaster information sharing platform, real-time exchange of disaster situation information is achieved, which enhances communication and collaboration between villagers and the government, consequently improving the synergistic efficiency between individuals and governmental bodies. Simultaneously, a villager-centered disaster prevention system is constructed. Through measures such as disaster prevention publicity and practical disaster response drills, villagers’ awareness of disasters and their capabilities for self and mutual rescue are elevated, ultimately strengthening the overall disaster resilience of rural areas in the Hengduan Mountains region.

Fingerprinting techniques can be used to quantify sand source contributions with applied relevance, such as the management of sand accumulation problems for desert railways traversing complex aeolian landscapes. This study applies the FingerPro model to elucidate the sand sources impacting the Golmud-Korla Railway (GKR) in northwest China. Sand samples were collected from three distinct sources: the Gobi, a low-lying coarse sand sheet (LCSS), and a dune, alongside mixture samples from sand deposits on railway fences. Sand (< 100 mu m) deposited on railway sand fences predominantly originated from the LCSS, contributing 83.44% and 76.59% to the < 63 mu m and 63-100 mu m particle size fractions, respectively. Conversely, the dune was the dominant source for particles ranging in size from 100 to 500 mu m, accounting for 75.40%. Annually, an estimated 1388.0 m(3) of sand from LCSS and 4987.2 m(3) of sand from the dune are transported to the 2-km-long sand fence in the upwind direction of the GKR. In terms of per-unit-area contribution, LCSS contributes the most (more than 3,700 m(3).km(-2)a(-1)), followed by the dune (1,534 m(3).km(-2)a(-1)), while the Gobi contributes the least (29.38 m(3).km(-2)a(-1)). These findings underscore the need for integrated sand control measures that address both LCSS and dunes. Consolidation of LCSS is needed to suppress dust emissions that affect railway equipment. Targeted dune control is needed to manage hazards from larger sand-sized particles (100-500 mu m) that obstruct railway sand fences. For arid regions with complex sedimentary environments, we recommend using differentiating particle size ranges in source differentiation analyses to capture variations in sediment grain size distributions with greater precision.

Frequent grassland fires have severely affected regional ecosystems as well as the production and living conditions of local residents. Grassland fire prevention capabilities constitute an integral part of the disaster prevention and mitigation system and play an important role in improving grassroots governance. To gain a deeper understanding of the practical foundation and influencing mechanisms of grassland fire prevention capabilities, establish an evaluation index system for prevention capabilities covering the four dimensions of disaster prevention, disaster resistance, disaster relief, and recovery. Combining micro-level survey data, a quantile regression model is used to analyze the influencing factors. The research findings indicate that (1) disaster resistance (0.49) plays a prominent role in grassland fire prevention capabilities, with economic foundations and individual disaster relief capabilities being particularly critical for overall improvement. Although residents have strong fire prevention awareness, their organizational collaboration capabilities are relatively weak, and there are significant differences in prevention capabilities across regions, necessitating tailored, precise enhancements. (2) There are significant differences in prevention capabilities among residents of different agricultural and pastoral production types, with semi-agricultural and semi-pastoral areas having the strongest comprehensive capabilities and pastoral areas relatively weaker. (3) A significant analysis of factors influencing grassland fire prevention capabilities: effective and diverse risk communication is a prerequisite for enhancing residents’ prevention capabilities; the level of panic regarding grassland fires and road infrastructure are important influencing factors, but residents’ understanding of climate change and grassroots organizations’ capacity for mechanism construction have insignificant impacts. Therefore, in future grassland fire disaster prevention and mitigation efforts, it is essential to strengthen risk communication, improve infrastructure, monitor environmental changes and the spatiotemporal patterns of grassland fires, enhance residents’ understanding of climate change, reinforce the emergency response capabilities of grassroots organizations, and stimulate public participation awareness to collectively build a multi-tiered grassland fire prevention system.

Recognized as the world’s “Third Pole”, the Qinghai–Xizang Plateau poses significant challenges to human health due to its harsh environment. With improved transportation and a tourism boom industry bringing over 90 million low-altitude residents to the plateau annually, hypoxia has become a critical concern. This study analyzes oxygen content data (2017–2022) together with environmental variables including elevation, temperature, precipitation, and vegetation cover, using the GeoDetector method to identify key drivers of near-surface oxygen distribution. Within the framework of disaster system theory, we evaluated the risk of hypoxia among short-term residents. Results show that the near-surface oxygen distribution across the plateau is primarily regulated by climatic and topographic factors. Interactions among environmental variables markedly enhance the explanatory power for spatial variation in oxygen content, with the coupled effects of humidity, atmospheric pressure, elevation, and temperature being especially pronounced. A high hypoxia hazard prevails across the plateau, particularly in the high-altitude western, northern, and central regions. The spatial distribution of hypoxia risk is strongly shaped by human activities, with high-risk zones clustering in densely populated towns, transportation corridors, and regions of intensive tourism. This results in a distinctive coexistence of “high hazard–low exposure” and “low hazard–high exposure” patterns. These findings provide scientific insights for tourism planning, health protection, and risk management in plateau regions.

The linkage between late Holocene climate change and hydrogeomorphic evolution is poorly understood in the Tibetan Plateau (TP) region. In this paper, we describe a 2.16 m core (ZGC21) drilled in Drigu Co of the Yamdrok Yumtso Basin, in southern part of the TP to address this issue. Specifically, we obtained AMS-14C ages, and measurements of water content, grain size, loss on ignition, total organic carbon, total nitrogen, pollen, and carbonate delta 18O. The findings show that the ZGC21 core comprises 23 layers including 5 sedimentary facies and represents a continuous record for the past 4400 years. Owing to its well-defined layers and an average sedimentation rate of 21 yr/cm, this core serves as a robust geological archive for reconstructing variations in climate and hydrogeomorphic processes influenced by the Indian Summer Monsoon (ISM). We report that a warm-dry climate occurred during 4400-4300 a B.P., 3500-1830 a B.P., and 1320-850 a B.P., whereas a cold-wet climate occurred from 4300 to 3500 a B.P. and 850-100 a B.P. in the study region. Solar irradiance modulated the ISM intensity, which directly affected climate dynamics on the southern TP. Furthermore, the formation of distinct layers is attributed to the combination of historical variations in the Drigu Co water level, sediment influx, and the growth conditions of aquatic vegetation within the basin under the contemporaneous variability of the ISM. Our findings provide a reliable paleoenvironmental framework for investigating the historical dynamics of human settlements and civilization (i.e., Qugong, Changgogou, Bangga sites, and the Tubo Dynasty) in the southern part of the TP.

The Alpine Periglacial Weathering Zone (APWZ) is a critical transitional belt between alpine vegetation and glaciers, and a highly sensitive region to climate change. Its dynamic variations profoundly reflect the surface environment’s response to climatic shifts. Taking Gongga Mountain as the study area, this study utilizes summer Landsat imagery from 1986 to 2024 and constructs a remote sensing method based on NDVI and NDSI indices using the Otsu thresholding algorithm on the Google Earth Engine platform to automatically extract the positions of the upper limit of vegetation and the snowline. Results show that over the past four decades, the APWZ in Gongga Mountain has exhibited a continuous upward shift, with the mean elevation rising from 4101 m to 4575 m. The upper limit of vegetation advanced at an average rate of 17.43 m/a, significantly faster than the snowline shift (3.9 m/a). The APWZ also experienced substantial areal shrinkage, with an average annual reduction of approximately 13.84 km2, highlighting the differential responses of various surface cover types to warming. Spatially, the most pronounced changes occurred in high-elevation zones (4200–4700 m), moderate slopes (25–33°), and sun-facing aspects (east, southeast, and south slopes), reflecting a typical climate–topography coupled driving mechanism. In the upper APWZ, glacier retreat has intensified weathering and increased debris accumulation, while the newly formed vegetation zone in the lower APWZ remains structurally fragile and unstable. Under extreme climatic disturbances, this setting is prone to triggering chain-type hazards such as landslides and debris flows. These findings enhance our capacity to monitor alpine ecological boundary changes and identify associated disaster risks, providing scientific support for managing climate-sensitive mountainous regions.

The Qinghai Plateau has a complex geographical environment and vast amounts of land with a sparse population, dispersed settlements, and a low traffic density. In the face of major disasters, the rational layout of emergency material reserve warehouses is crucial for reducing disaster losses, ensuring regional stability, and quickly restoring production and life. This paper starts by considering the rationality and timeliness of the location selection of provincial emergency material reserve warehouses, considering the distance costs of emergency material transportation on the Qinghai Plateau. By using a traffic accessibility analysis model combined with a location–allocation model and an L-A maximum coverage model, this study optimizes the location selection of emergency material reserve warehouses on the Qinghai Plateau. The research results show the following: (1) On the basis of the existing Golmud Depot and Chengxi Depot in Qinghai Province, it is necessary to add four more depots, i.e., the Yushu Depot, Gande Depot, Ping’an Depot, and Tongde Depot, to achieve the timely and efficient supply of emergency materials. (2) After the optimization, the layout of the six provincial emergency material reserve warehouses can achieve full coverage of Qinghai Province within 8 h in the event of major disasters, increasing the coverage by 20% compared to the original layout; the new plan allows for emergency material transportation to cover 87% of Qinghai Province within 4 h, an increase of 28% compared to before. (3) The optimized location selection plan for emergency material reserve warehouses saves 139 min of time costs, and the transportation efficiency is increased by 46% compared to the previous plan. The optimized location selection plan for emergency material reserve warehouses is instructive for the construction of emergency material reserve warehouses on the Qinghai–Tibet Plateau.