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Glaciers are considered to be 'climate-sensitive indicators' and 'solid reservoirs', and their changes significantly impact regional water security. The mass balance (MB) from 2011 to 2020 of the Qiyi Glacier in the northeast Tibetan Plateau is presented based on field observations. The glacier showed a persistent negative balance over 9 years of in-situ observations, with a mean MB of −0.51 m w.e. yr−1. The distributed energy-mass balance model was used for glacier MB reconstruction from 1980 to 2020. The daily meteorological data used in the model were from HAR v2 reanalysis data, with automatic weather stations located in the middle and upper parts of the glacier used for deviation correction. The average MB over the past 40 years of the Qiyi Glacier was −0.36 m w.e. yr−1 with the mass losses since the beginning of the 21st century, being greater than those in the past. The glacier runoff shows a significant increasing trend, contributing ∼81% of the downstream river runoff. The albedo disparity indicates that the net shortwave radiation is much higher in the ablation zone than in the accumulation zone, accelerating ablation-area expansion and glacier mass depletion. The MB of the Qiyi Glacier is more sensitive to temperature and incoming shortwave radiation variation than precipitation. The MB presented a non-linear reaction to the temperature and incoming shortwave radiation. Under future climate warming, the Qiyi Glacier will be increasingly likely to deviate from the equilibrium state, thereby exacerbating regional water balance risks. It is found that the mass losses of eastern glaciers are higher than those of western glaciers, indicating significant spatial heterogeneity that may be attributable to the lower altitude and smaller area distribution of the eastern glaciers. [ABSTRACT FROM AUTHOR]

Surface albedo plays a pivotal role in the Earth's energy balance and climate. This study conducted an analysis of the spatial distribution patterns and temporal evolution of albedo, normalized difference vegetation index (NDVI), normalized difference snow index snow cover (NSC), and land surface temperature (LST) within the Qilian Mountains (QLMs) from 2001 to 2022. This study evaluated the spatiotemporal correlations of albedo with NSC, NDVI, and LST at various temporal scales. Additionally, the study quantified the driving forces and relative contributions of topographic and natural factors to the albedo variation of the QLMs using geographic detectors. The findings revealed the following insights: (1) Approximately 22.8% of the QLMs exhibited significant changes in albedo. The annual average albedo and NSC exhibited a minor decline with rates of −0.00037 and −0.05083 (Sen's slope), respectively. Conversely, LST displayed a marginal increase at a rate of 0.00564, while NDVI experienced a notable increase at a rate of 0.00178. (2) The seasonal fluctuations of NSC, LST, and vegetation collectively influenced the overall albedo changes in the Qilian Mountains. Notably, the highly similar trends and significant correlations between albedo and NSC, whether in intra-annual monthly variations, multi-year monthly anomalies, or regional multi-year mean trends, indicate that the changes in snow albedo reflected by NSC played a major role. Additionally, the area proportion and corresponding average elevation of PSI (permanent snow and ice regions) slightly increased, potentially suggesting a slow upward shift of the high mountain snowline in the QLMs. (3) NDVI, land cover type (LCT), and the Digital Elevation Model (DEM, which means elevation) played key roles in shaping the spatial pattern of albedo. Additionally, the spatial distribution of albedo was most significantly influenced by the interaction between slope and NDVI. [ABSTRACT FROM AUTHOR]

Variations in evapotranspiration and their sensitivity to controlling variables are pivotal for comprehending water balance dynamics and climate change, particularly in high‐altitude regions such as the Qilian mountains. Environmental shifts are bound to disrupt local water cycles and balance, with significant implications for these alpine areas. To enhance our understanding of evapotranspiration variability across different altitudes within the Qilian Mountains' high‐elevation region and to assess the model's adaptability and responsiveness to environmental factors, our study involved measuring actual evapotranspiration at three distinct elevations. This was achieved using meteorological stations and continuous data from a weighing‐type microlysimeter at the Shaliu River basin's gradients of 3797, 4250 and 4303 m, spanning the growing seasons from June 2020 to October 2022. We utilized 10 models to calculate the value of reference evapotranspiration, which were then matched against actual evapotranspiration data to identify the most appropriate model. Our research found that across the three elevation gradients, the daily average evapotranspiration were 3.663, 3.845 and 4.317 mm day−1, respectively. Across the three elevations, with consistent intra‐annual fluctuations. Notably, August experienced the highest monthly evapotranspiration at 4.750 mm day−1, and reach peak at 10:00 and 15:00 on the three elevation gradients. The results from the simulation of the 10 models indicate that the Dalton model is more suitable for our study area compared with the other models, showing the best R2, root mean square error and percentage error values. Partial least squares regression analysis, coupled with an enhanced regression tree model, identified precipitation as the most critical factor, with a variable importance in projection score of 2.079, contributing 52.6% to evapotranspiration. Collectively, precipitation were identified as key factors influencing evapotranspiration variability within our research area. Our study's insights are valuable for anticipating the impacts of future climate change. This conclusion is instrumental for refining water budget projections in Alpine regions under climate change scenarios. [ABSTRACT FROM AUTHOR]

Soil moisture， as a key hydrological variable connecting the surface and atmospheric water and heat exchange， affects the land-air water and heat exchange and carbon cycle process.However， due to the difficulty in monitoring soil moisture in alpine mountain areas， there are some difficulties in related research.The study of time stability can reduce the difficulty of soil moisture acquisition by selecting representative points.In this study， the slope of Shangzhangfanggou grassland in Shiyang River basin of Qilian Mountain was selected to set up a high-density and high-time resolution soil moisture monitoring network to explore the temporal and spatial variation and temporal stability of soil moisture on the slope scale in alpine mountainous areas.The research results show that： （1） The surface soil moisture （10 cm， 15.90%） is significantly higher than that in the deep layer （50 cm， 11.78%）， and its temporal variability （CvT=19.46%） is also stronger than that in the deep layer （CvT=10.67%）， but its spatial variability （CvS=20.05%） is weaker than that in the deep layer （CvS=27.06%）.（2） The time stability Index of Temporal Stability （0.24） is stronger than that of the deep layer （0.34）， and the surface layer and the deep layer can represent the surface soil moisture of the slope through 3 or 5 soil moisture monitoring points respectively （R2> 0.90）.（3） Slope position and soil hydrological properties have obvious influence on time stability， and the time stability point is more likely to appear at the position with larger bulk density and smaller shape parameter n under the slope.The research results are helpful to better understand the temporal and spatial variation law， temporal stability characteristics and control function of soil moisture on slope in alpine mountain areas.

Global warming in tandem with surface albedo reduction caused by black carbon (BC) deposition on glaciers accelerated glacier melting; however, their respective contributions remain unclear. Glaciers in the Qilian Mountains are crucial for the development of oases in the Hexi Corridor; however, their area has decreased by more than 20% over the past half-century. Thus, this study developed a dynamic deposition model for light-absorbing particles (LAPs), coupled with a surface energy and mass balance model. We comprehensively assessed the effects of BC and warming on the melting of a typical glacier in the Qilian Mountains based on the coupled model. BC on the glacier surface caused 13.1% of annual glacier-wide melting, of which directly deposited atmospheric BC reduced the surface albedo by 0.02 and accounted for 9.1% of glacier melting. The air temperature during 2000–2010 has increased by 1.5 °C relative to that during the 1950s, accounting for 51.9% of current glacier melting. Meanwhile, BC emission have increased by 4.6 times compared to those of the early Industrial Revolution recorded in an ice core, accounting conservatively for 6.3% of current glacier melting. Mitigating BC emissions has a limited influence on current glacier melting; however, in the long-term, mitigation should exert a noteworthy impact on glacier melting through the self-purification of glaciers.

The Qilian Mountains (QLM) act as an "ecological security barrier" in western China, impacting the downstream ecosystems and water resource utilization. However, the hydrological evolution of the QLM during the last millennium remains controversial, and their ecological response to climate change is poorly understood. We present a pH record based on the brGDGTs (branched glycerol dialkyl glycerol tetraethers) of a 14C-dated sediment core from Lake Maozangtianchi in the QLM. We combined this record with element contents determined by scanning XRF and grain size to reconstruct the summer monsoon precipitation variability over the last 900 years. We also reconstructed the history of eco-environmental changes from the total n -alkane contents. On centennial scales, local precipitation exhibited peaks during the intervals of 1100‒1300 CE and 1750‒2000 CE, as well as between 1400‒1750 CE. Additionally, abrupt decreases in precipitation occurred during the transition from the Medieval Warm Period (MWP) to the Little Ice Age (LIA) (1300‒1400 CE). This pattern coherent with other hydroclimatic records from the monsoonal margin of northern China, likely resulted from the combined impact of the El Niño‒Southern Oscillation on tropical Pacific sea-surface temperatures and the meridional shift of the Intertropical Convergence Zone. In addition, a coupled relationship between plant biomass in the Lake Maozangtianchi watershed and fluctuations in monsoon precipitation was observed, with higher plant biomass during 1100‒1200 CE, 1750‒1900 CE, and 1950‒2000 CE, and lower biomass during 1200‒1400 CE and 1900‒1950 CE. However, during 1400‒1750 CE, plant biomass exhibited a minor increasing trend, deviating from its usual correlation with monsoon precipitation. Despite precipitation usually being the primary climatic factor influencing plant biomass in the QLM, during the LIA, nutrients transported by dust and decreased evapotranspiration became pivotal in bolstering plant growth. Our research emphasizes the significant moderating effects of exogenic dust on vegetation changes in alpine ecosystems. [ABSTRACT FROM AUTHOR]

Copyright of Acta Sedimentologica Sinica is the property of Acta Sedimentologica Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Soil organic carbon (SOC) is an important component of the global carbon pool, whose accumulation and decomposition affect the balance of the global carbon cycle and climate change. However, understanding of the responses of SOC in alpine ecosystems to climate change is quite limited, especially in the seasonal-frozen soil zone. In order to understand the impact of soil moisture changes on the carbon cycle in alpine mountain ecosystems, we established two sample plots of the semi-shady and semi-sunny slopes in the subalpine meadow zone of the eastern part of Qilian Mountains, and collected soil samples to investigate the spatial and temporal changes of SOC and soil moisture and their relationships. The study indicated that the SOC content showed significant surface aggregation during the plant growing season, and that the influence of soil moisture on SOC was different in different slope directions and soil depths. The influence of soil moisture on SOC was greater on the semi-shady slope than on the semi-sunny slope. Among different soil layer depths, the soil moisture most significantly affected SOC in the soil layer of 20-40 cm. This study provides a theoretical basis for the study of carbon stocks and carbon cycling at high altitudes. [ABSTRACT FROM AUTHOR]

Water resources in the soil play an essential role in hydrological processes and ecosystem functions on the Tibetan Plateau. However, accurately measuring soil moisture distribution in this region presents challenges due to the diverse ecosystem types, complex terrain, and harsh environmental conditions. In this study, we introduce an approach for estimating mesoscale soil moisture in the Qilian Mountains (QLM) region of the eastern Tibetan Plateau using a cosmic-ray neutron rover. Soil moisture estimates derived from neutron count rates, newly adjusted by vegetation effects, demonstrated good agreement with soil moisture measurements obtained through soil sampling at 26 calibration sites across the region (RMSE = 0.025 g g−1). The calibration parameter N0_NDVI was 443 cpm in the QLM. Utilizing NDVI as vegetation correction method showed potential improvements in the accuracy of converting neutron counts to soil moisture across the diverse mountainous ecosystem types. The newly developed calibration equation provided a high-precision, high spatial resolution soil moisture transect across various landscapes measured by the rover. The average mesoscale soil moisture along the rover route varied by ecosystem types, with values of 0.10 g/g in deserts, 0.17 g/g in grasslands, 0.13 g/g in forests, 0.18 g/g in subalpine shrublands, and 0.20 g/g in croplands. Land cover types emerged as crucial determinants of mesoscale soil moisture variability in the QLM region. These findings offer valuable mesoscale soil moisture data and new insights into soil water information at the transect scale across diverse ecosystem types in the Tibetan Plateau.

Based on soil temperature and humidity and meteorological data at different elevations during the 2020-2021 growing season in the Pailugou watershed of Qilian Mountain， this study analyzed the variation characteristics of soil temperature and humidity and the relationship with meteorological factors， and determined the main meteorological factors affecting soil temperature and humidity.The results showed that： （1） soil temperature tended to increase and then decreased during the growing season （2020）， with a gradual increase in soil temperature from May to August （3.93 ℃） and a decrease from September to October （2.44 ℃）.Meanwhile， soil temperature showed a fluctuating increase with increasing elevation and a gradual decrease with increasing depth of soil layer.（2） Soil moisture showed considerable variation within the growing season， with a general trend of increase and then decrease （2020）， with the lowest soil moisture in May （0.164 m3·m-3） and the highest soil moisture in September （0.318 m3·m-3）.（3） The variation of soil moisture increases with elevation and decreases with the depth of the soil layer.（4） The main meteorological elements affecting soil temperature are air temperature and relative humidity， while soil moisture is mainly affected by air temperature and vapor pressure deficit.

Population density estimation is integral to the effective conservation and management of wildlife. The snow leopard Panthera uncia is categorized as Vulnerable on the IUCN Red List, and reliable information on its density is a prerequisite for its conservation and management. Little is known about the status of the snow leopard in the central and eastern Qilian Mountains, China. To address this, we estimated the population density of the snow leopard using a spatially explicit capture–recapture model based on camera trapping in Machang in the central and eastern Qilian Mountains during January–March 2019. We set up 40 camera traps and recorded 84 separate snow leopard captures over 3,024 trap-days. We identified 18 individual snow leopards and estimated their density to be 2.26/100 km2. Our study provides baseline information on the snow leopard and the first population estimate for the species in the central and eastern Qilian Mountains.

Objective] In order to screen out the most suitable forage species and the best mixed sowing type, to provide scientific basis for ecological restoration of degraded grassland. [Method] The adaptability research of reseeding and mixed sowing of the 9 species of Cleistogenes songorica, Krascheninnikovia ceratoides, Artemisia desertorum, Agriophyllum squarrosum, Haloxylon ammodendron, Seriphidium nitrosum, Kochia prostrata, Sarcozygium xanthoxylon and Melilotus suaveolens in the temperate desert steppe at the northern foot of Qilian Mountains was conducted. The indexes of growth height, coverage and yield of different varieties and different mixed sowing combinations were investigated and recorded. [Result] The results showed that the growth and development performance of Cleistogenes songorica, Artemisia desertorum and Agriophyllum squarrosum were better than other varieties, and the grass yield was higher, were 6 680.5,5 329.5 and 5 259.0 kg/hm², respectively, with strong regional adaptability.Agriophyllum squarrosum + Krascheninnikovia ceratoides + Cleistogenes songorica + Melilotus suaveolens mixture and Cleistogenes songorica+Artemisia desertorum + Krascheninnikovia ceratoides + Seriphidium nitrosum mixture, could significantly increase the yield of grassland, and were the best type of mixed sowing for the restoration in degraded desert grassland. [Conclusion] The adaptability and yield of the Cleistogenes songorica, Artemisia desertorum and Agriophyllum squarrosum were good, so they could be used as the suitable grass species for desert steppe improvement. [ABSTRACT FROM AUTHOR]

In this study, we conducted field campaigns at two mountain‐top observatories on the Qilian Mountains (QLM) in the northeastern Tibetan Plateau of China, which plays a vital role in sustaining water resources for the downstream arid and semi‐arid regions. The two observatories, Waliguan Baseline Observatory (WLG) and Laohugou station (LHG), are situated on the eastern and western edge of the QLM, respectively. The objectives of this study were to examine the properties of atmospheric aerosols, CCN concentrations (NCCN) at varying supersaturation levels (SS = 0.2%–1.0%), and the hygroscopic nature of aerosols in the QLM, especially during the formation of orographic cloud. Notably, the average aerosol concentration and NCCN was approximately 2–3 factors higher at WLG compared to LHG. The chemical compositions of aerosols were primarily dominated by sulfate and organic aerosol (OA) at these two sites. A very high hygroscopicity parameter of aerosol calculated using chemical composition was observed at these two sites (0.37 ± 0.03 at LHG vs. 0.30 ± 0.04 at WLG). Enhanced aerosol loading episodes impacted by anthropogenic emission were observed at these two sites. Exploration on high‐loading cases at each site, we found that the CCN activity was dominated by aerosol size, but the chemical processes of aerosol during the formation of orographic cloud could also be important in CCN activity, especially for low SS conditions. These findings collectively underscore the significant impact of anthropogenic air plumes on CCN concentrations in the QLM and their potential influence on precipitation patterns. Plain Language Summary: The Qilian Mountains (QLM), situated in the northeastern Tibetan Plateau of China, have been constructed as a national park, dedicated to protecting its fragile ecological environment. Renowned for its "wet island" effect, the mountains serve as a crucial water resource for the downstream residents in northwest China. Orographic clouds, a primary source of precipitation in these mountains, heavily rely on the presence of cloud condensation nuclei (CCN), typically dominated by natural mineral dust due to its arid and semi‐arid regions around. In recent years, rapid urbanization and heavy human activities around has introduced a significant influx of anthropogenic aerosols. However, the impact of anthropogenic aerosol on the orographic cloud is unclear, especially during summer season when natural mineral dust emissions are limited. To unravel this mystery, we conducted campaigns at two mountain‐top observatories to explore the impact of anthropogenic aerosol transport from low elevation regions during summer season to mountain areas. Our findings highlight the substantial impact of anthropogenic aerosols on CCN concentrations, which offer valuable insights into the understanding the interaction of aerosol and cloud, and potential impact on precipitation in this mountain region. Key Points: Two mountain‐top studies were explored to characterize aerosol and CCN on the QLM in the northeastern TP of ChinaAn overall low NCCN values were observed in these mountain areas, but the concentration at the east was 2–3 times higher than the westElevated NCCN occurred at these two sites when anthropogenic pollutants were transported upslope [ABSTRACT FROM AUTHOR]

The study explores the impact of mine grassland restoration on plant communities and soil properties in alpine grasslands, a subject of significant interest due to the observed relationship between grassland changes, plant communities, and soil properties. While prior research has mainly focused on the consequences of grassland degradation on plant diversity and soil characteristics, the specific effects of varying restoration degrees in alpine mining grasslands at the regional scale remain poorly understood. To address this knowledge gap, we established 15 sampling plots (0.5m×0.5m) across five different restoration degrees within alpine mining grasslands in the Qilian Mountains, China. Our objective was to assess the variations in plant diversity and soil properties along these restoration gradients. We conducted comprehensive analyses, encompassing soil properties [soil water content (SWC), available nitrogen (AN), total phosphorus (TP), nitrate nitrogen (NO3-N), ammonium nitrogen (NH4-N), total nitrogen (TN), available phosphorus (AP), soil organic carbon (SOC), nitrate nitrogen, soil pH, and electrical conductivity (EC)], plant characteristics (height, density, frequency, coverage, and aboveground biomass), and plant diversity indices (Simpson, Shannon-Wiener, Margalef, Dominance, and Evenness indexes). Our findings included the identification and collection of 18 plant species from 11 families and 16 genera across the five restoration degrees: Very Low Restoration Degree (VLRD), Low Restoration Degree (LRD), Moderate Restoration Degree (MRD), High Restoration Degree (HRD), and Natural Grassland (NGL). Notably, species like Carex duriuscula, Cyperus rotundus, and Polygonum viviparum showed signs of recovery. Principal component analysis and Pearson correlation analysis revealed that soil pH, SWC, SOC, NO3-N, and AN were the primary environmental factors influencing plant communities. Specifically, soil pH and EC decreased as restoration levels increased, while SWC, AN, TP, NH4-N, TN, AP, SOC, and NO3-N exhibited a gradual increase with greater restoration efforts. Furthermore, the HRD plant community demonstrated similarities to the NGL, indicating the most effective natural recovery. In conclusion, our study provides valuable insights into the responses of plant community characteristics, plant diversity, and soil properties across varying restoration degrees to environmental factors. It also elucidates the characteristics of plant communities along recovery gradients in alpine grasslands. [ABSTRACT FROM AUTHOR]

Surface runoff is a major component of the hydrological cycle, and it is essential for supporting the ecosystem services provided by grassland and forest ecosystems. It is of practical importance to understand the mechanisms and the dynamic processes of runoff in a river's basin, and in this study, we focused on the restored montane Pailugou Basin in the Qilian Mountains, Gansu Province, China, since its water status is extremely important for the large arid area and local economies therein. Our purpose was to determine the annual variation in the surface runoff in the Pailugou Basin because it is important to understand the influence of climate fluctuations on surface water resources and the economy of the basin. In addition, little is known about the annual variations in precipitation and runoff in this region of the world. Daily atmospheric precipitation, air temperature and runoff data from 2000 to 2019 were analyzed by the calculation of the uneven annual distribution of surface runoff, the calculation of the complete adjustment coefficient, and the vector accumulation expressed by the concentration degree. We also used the cumulative anomaly approach to determine the interannual variation trend of runoff, while the change trend was quantified by the sliding average method. Finally, we used the Mann–Kendall mutation test method and regression analysis to establish the time-series trend for precipitation and runoff and to determine the period of abrupt runoff changes. The results indicated concentrated and positive distributions of surface runoff on an annual basis, with a small degree of dispersion, and an explicit concentration of extreme flows. The relative variation ranges exhibited a decreasing trend, and the distribution of the surface runoff gradually was uniform over the year. The runoff was highest from July to September (85% of the annual total). We also determined that annual surface runoff in the basin fluctuated over the 20-year period but showed an overall increasing trend, increasing by 3.94 × 105 m3, with an average increase rate of 0.42 × 105 m3 every ten years. From 2005 to 2014, the annual runoff and the proportion of runoff in the flood season (July to September) to the annual runoff fluctuated greatly. The correlation between the runoff and precipitation was significant (r = 0.839, p < 0.05), whereas the correlation between air temperature and surface runoff was low (r = 0.421, p < 0.05). [ABSTRACT FROM AUTHOR]

The water cycle in the soil‐plant‐atmosphere continuum is an important element of hydrological and ecological studies, and differences in the composition characteristics of hydrogen and oxygen stable isotopes in different water bodies can indicate water cycling processes. In this study, hydrogen and oxygen isotopes of precipitation, soil water and plant water samples had been collected in the subalpine scrubland of the Qilian Mountains from May to October 2019. The Craig‐Gordon model, the isotopic steady‐state (ISS) assumption, the Keeling Plot model and the two‐source mixing model were used to analyse the stable isotope compositions of different water bodies, the stable isotope characteristics of water vapour of soil evaporation and plant transpiration and the variation of evapotranspiration in the SPAC of the subalpine scrubland. The results showed that plant transpiration (FT) contributed 87.28% and 86.95% to evapotranspiration and soil evaporation (FE) contributed 12.72% and 13.05% to evapotranspiration in the growing season on semi‐sunny and semi‐shaded aspects, respectively, indicating that evapotranspiration in the subalpine scrubland mainly came from the transpiration of scrubland plants. In the early of the growing season (May–June), due to the rapid expansion of plant leaves, the contribution of transpiration to evapotranspiration was at a high level, which intensified transpiration and led to a gradual increase of the transpiration contribution. In the middle of the growing season (July–August), owing to better conditions of rain and heat that made plants grow vigorously, plant transpiration made the highest contribution to evapotranspiration more than 90%, which caused to an overwhelming contribution of plant transpiration to evapotranspiration. In the later of growing season (September to October), the contribution of plant transpiration to evapotranspiration decreased significantly while that of soil evaporation increased, which was because plant photosynthesis and respiration gradually declined for losing their leaves of scrub plants and the relative atmospheric humidity was lower. [ABSTRACT FROM AUTHOR]

To understand how the soil microbial community structure responds to vegetation restoration in alpine mining areas, this study specifically examines the grassland ecosystem in the Qianmalong mining area of the Qilian Mountains after five years of artificial restoration. High-throughput sequencing methods were employed to analyze soil bacteria and fungi microbial characteristics in diverse grassland communities. Combined with modifications in vegetation diversity as well as soil physicochemical properties, the impact of vegetation restoration on soil microbiome diversity in this alpine mining area was investigated. The findings indicated that the dominant plants were Cyperus rotundus, Carex spp., and Elymus nutans. As the extent of the grassland's restoration increased, the number of plant species, importance values, and plant community diversity showed an increasing trend. The plant functional groups were mainly dominated by Cyperaceae, followed by Poaceae. Plant height, density, plant cover, frequency, and aboveground biomass showed an increasing trend, and soil water content (SWC) increased. While soil pH and soil electrical conductivity (EC) exhibited a declining trend, available phosphorus (AP), total phosphorus (TP), total nitrogen (TN), nitrate nitrogen (NO3-N), soil organic carbon (SOC), and soil water content (SWC) showed an increasing trend. The dominant bacterial communities were Actinobacteriota, Proteobacteria, Acidobacteriota, Chloroflexi, Firmicutes, and Gemmatimonadota, while the dominant fungal communities were Ascomycota, Mortierellomycota, Basidiomycota, unclassified_k_Fungi, and Glomeromycota. Significant differences were detected within soil microbial community composition among different degrees of restoration grasslands, with bacteria generally dominating over fungi. SWC, TP, and TN were found to be the main soil physicochemical factors affecting the distribution of soil bacterial communities' structure; however, SOC, TN, and NO3-N were the primary factors influencing the soil distribution of fungal communities. The results of this study indicate that different degrees of vegetation restoration in alpine mining areas can significantly affect soil bacterial and fungal communities, and the degree of restoration has varying effects on the soil bacteria and fungi community structure in alpine mining areas. [ABSTRACT FROM AUTHOR]

Understanding runoff dynamics is vital for effective water management in climate-affected areas. This study focuses on the Dayekou basin in China's Qilian Mountains, known for their high climate variability. Using 25 years of data (1994–2018) on river runoff, precipitation, and temperature, statistical methods were applied to explore the annual variations and climate change impacts on these parameters. Results reveal a significant variability in the river runoff (132.27 to 225.03 mm), precipitation (340.19 to 433.29 mm), and average temperature (1.38 to 2.08 °C) over the period. Decadal rising rates average 17 mm for runoff, 17 mm for precipitation, and 0.25 °C for temperature, with the peak precipitation and runoff occurring in 1998–2000, 2008, and 2016. The annual runoff distribution also exhibited a unimodal pattern, peaking at 39.68 mm in July. The cumulative runoff during low periods constituted only 13.84% of the annual total, concentrated in the second half of the year, particularly during the June-October flood season. The correlation analysis underscored a strong relationship between river runoff and precipitation (correlation coefficient > 0.80), while the temperature correlation was weaker (correlation coefficient < 0.80). This 25-year analysis provides valuable insights into runoff variation, elucidating the interconnected effects of temperature and precipitation in the Dayekou basin, with substantial implications for sustainable development amid climate challenges. [ABSTRACT FROM AUTHOR]

Copyright of Plateau Meteorology is the property of Plateau Meteorology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To evaluate the soil quality of alpine farmland and elucidate the key factors influencing productivity levels under the current agricultural paradigm, we conducted an extensive collection of soil samples. In total, 234 soil samples (0–20 cm) were collected from Menyuan County, the heartland of the southern slope of the Qilian Mountains. These samples represented four predominant soil types, including cold calcic soil, luvic chernozem, calcareous meadow soil, and calcareous gray cinnamon soil. Moreover, by employing principal component analysis, we established a minimum data set (MDS) that encapsulated the essential parameters for the comprehensive evaluation of the soil quality of farmland in the study area. Upon evaluating the soil quality index, the rankings were as follows: luvic chernozem (0.63) > calcareous gray cinnamon soil (0.58) > calcareous meadow soil (0.58) > cold calcic soil (0.55). Overall, the results highlighted that the significant impact of soil total nitrogen (TN), available potassium (AK), and soil water content (SWC) on soil quality within the study area. Therefore, in the context of land management practices, careful attention should be paid to the management of soil TN, AK content, and SWC to avoid the degradation of cultivated land into abandoned fields. [ABSTRACT FROM AUTHOR]

Samples of scrub plants and soil were collected from May to October 2019 in the subalpine scrub zone of the Qilian Mountains. Based on measured oxygen isotope values (δ18O) in plant xylem water and soil water, the multivariate linear mixed model (IsoSource) and the proportional similarity index (PS index) were used to analyze the using proportion for each potential water source and the competition relationship for water use of scrub plants in different growing periods and habitats. The results showed that the soil water content gradually decreased with increasing depth of the soil layer, with the maximum value in the soil layer of 0–10 cm. Most of the scrub plants mainly used soil water in the soil layer of 0–30 cm during the different periods of growing season, but Salix sclerophylla Anderss. and Salix oritrepha Schneid. on the semi-sunny slope habitat mainly used soil water in the soil layer of 40–80 cm during the middle period of growing season (July–August), with the proportion of 59.5% and 52.1%, respectively; and Potentilla fruticosa Linn. and Salix cupularis Rehd. on the semi-shady slope habitat mainly used soil water in the soil layer of 30–60 cm during the early period of growing season (May–June), with the proportion of 61.1% and 49.7%, respectively. The competition relationships of scrub plants for water use varied during different periods of growing season (P < 0.05). On the semi-sunny slope habitat, they were fiercest for Salix cupularis Rehd. and Rhododendron thymifolium Maxim., Potentilla fruticosa Linn., and Salix sclerophylla Anderss. during the early period of growing season; Salix cupularis Rehd. and Rhododendron thymifolium Maxim. during the middle period of growing season, and Salix sclerophylla Anderss. and Salix oritrepha Schneid. during the end period of growing season (September–October). On the semi-shady slope habitat, they were fiercest for Salix oritrepha Schneid. and Caragana jubata (Pall.) Poir. during the early period of growing season; Rhododendron przewalskii Maxim. and Rhododendron thymifolium Maxim. during the middle period of growing season; and Salix cupularis Rehd. and Salix oritrepha Schneid. during the end period of growing season. This study reveals the competitive relationship of scrub plants for water use in the subalpine zone and their response to environmental changes, so as to provide theoretical references for the ecological conservation in the ecologically fragile areas of the Qilian Mountains. [ABSTRACT FROM AUTHOR]

Population density estimation is integral to the effective conservation and management of wildlife. The snow leopard Panthera uncia is categorized as Vulnerable on the IUCN Red List, and reliable information on its density is a prerequisite for its conservation and management. Little is known about the status of the snow leopard in the central and eastern Qilian Mountains, China. To address this, we estimated the population density of the snow leopard using a spatially explicit capture–recapture model based on camera trapping in Machang in the central and eastern Qilian Mountains during January–March 2019. We set up 40 camera traps and recorded 84 separate snow leopard captures over 3,024 trap-days. We identified 18 individual snow leopards and estimated their density to be 2.26/100 km2. Our study provides baseline information on the snow leopard and the first population estimate for the species in the central and eastern Qilian Mountains. [ABSTRACT FROM AUTHOR]

Ecotourism is the main trend of global tourism development, and evaluating the ecotourism environmental carrying capacity (EECC) of ecologically fragile areas can provide a scientific basis for the sustainable development of regional tourism. This study uses the typical fragile mountain area, the Qilian Mountains (QLMs), as an example and analyzes the spatial and temporal changes in EECC by constructing an evaluation indicator system of EECC, which is based on the framework of "natural ecological environment support—socio-economic pressure—tourism activity pressure". In the results, it is found that the natural ecological environment support, socio-economic pressure, and tourism activity pressure in the QLMs all present a spatial distribution pattern of higher in the southeast and lower in the northwest. From a temporal perspective, most of the indicators of different subsystems show an increasing trend. The whole area of EECC in the QLMs shows an increasing trend in 85.4% of the region, while the EECC in some areas in the southeastern and northern parts shows a decreasing trend. Comparing different time periods, it is found that the EECC in the whole region shows an increasing trend from 2000 to 2010, while the proportion of areas with a decreasing trend in EECC from 2010 to 2018 reaches 67.1%. The research results can provide a scientific basis for the sustainable development of ecotourism in the QLMs and other similar regions in the world, and they further contribute to the protection of the ecological environment. [ABSTRACT FROM AUTHOR]

Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Surface albedo plays a pivotal role in the Earth’s energy balance and climate. This study conducted an analysis of the spatial distribution patterns and temporal evolution of albedo, normalized difference vegetation index (NDVI), normalized difference snow index snow cover (NSC), and land surface temperature (LST) within the Qilian Mountains (QLMs) from 2001 to 2022. This study evaluated the spatiotemporal correlations of albedo with NSC, NDVI, and LST at various temporal scales. Additionally, the study quantified the driving forces and relative contributions of topographic and natural factors to the albedo variation of the QLMs using geographic detectors. The findings revealed the following insights: (1) Approximately 22.8% of the QLMs exhibited significant changes in albedo. The annual average albedo and NSC exhibited a minor decline with rates of −0.00037 and −0.05083 (Sen’s slope), respectively. Conversely, LST displayed a marginal increase at a rate of 0.00564, while NDVI experienced a notable increase at a rate of 0.00178. (2) The seasonal fluctuations of NSC, LST, and vegetation collectively influenced the overall albedo changes in the Qilian Mountains. Notably, the highly similar trends and significant correlations between albedo and NSC, whether in intra-annual monthly variations, multi-year monthly anomalies, or regional multi-year mean trends, indicate that the changes in snow albedo reflected by NSC played a major role. Additionally, the area proportion and corresponding average elevation of PSI (permanent snow and ice regions) slightly increased, potentially suggesting a slow upward shift of the high mountain snowline in the QLMs. (3) NDVI, land cover type (LCT), and the Digital Elevation Model (DEM, which means elevation) played key roles in shaping the spatial pattern of albedo. Additionally, the spatial distribution of albedo was most significantly influenced by the interaction between slope and NDVI.

Tree radial growth can have significantly different responses to climate change depending on the environment. To elucidate the effects of climate on radial growth and stable carbon isotope (δ13C) fractionation of Qinghai spruce (Picea crassifolia), a widely distributed native conifer in northwestern China in different environments, we developed chronologies for tree-ring widths and δ13C in trees on the southern and northern slopes of the Qilian Mountains, and analysed the relationship between these tree-ring variables and major climatic factors. Tree-ring widths were strongly influenced by climatic factors early in the growing season, and the radial growth in trees on the northern slopes was more sensitive to climate than in trees on the southern. Tree-ring δ13C was more sensitive to climate than radial growth. δ13C fractionation was mainly influenced by summer temperature and precipitation early in the growing season. Stomatal conductance more strongly limited stable carbon isotope fractionation in tree rings than photosynthetic rate did. The response between tree rings and climate in mountains gradually weakened as climate warmed. Changes in radial growth and stable carbon isotope fractionation of P. crassifolia in response to climate in the Qilian Mountains may be further complicated by continued climate change. [ABSTRACT FROM AUTHOR]

Understanding temperature variability especially elevation dependent warming (EDW) in high-elevation mountain regions is critical for assessing the impacts of climate change on water resources including glacier melt, degradation of soils, and active layer thickness. EDW means that temperature is warming faster with the increase of altitude. In this study, we used observed temperature data during 1979–2017 from 23 meteorological stations in the Qilian Mountains (QLM) to analyze temperature trend with Mann-Kendall (MK) test and Sen's slope approach. Results showed that the warming trends for the annual temperature followed the order of T_min > T_mean > T_max and with a shift both occurred in 1997. Spring and summer temperature have a higher increasing trend than that in autumn and winter. T_mean shifts occurred in 1996 for spring and summer, in 1997 for autumn and winter. T_max shifts occurred in 1997 for spring and 1996 for summer. T_min shifts occurred in 1997 for spring, summer and winter as well as in 1999 for autumn. Annual mean diurnal temperature range (DTR) shows a significant decreasing trend (−0.18°C/10a) from 1979 to 2017. Summer mean DTR shows a significant decreasing trend (−0.26°C/10a) from 1979 to 2017 with a shift occurred in 2010. After removing longitude and latitude factors, we can learn that the warming enhancement rate of average annual temperature is 0.0673°C/km/10a, indicating that the temperature warming trend is accelerating with the continuous increase of altitude. The increase rate of elevation temperature is 0.0371°C/km/10a in spring, 0.0457°C/km/10a in summer, 0.0707°C/km/10a in autumn, and 0.0606°C/km/10a in winter, which indicates that there is a clear EDW in the QLM. The main causes of warming in the Qilian Mountains are human activities, cloudiness, ice-snow feedback and El Nino phenomenon. [ABSTRACT FROM AUTHOR]

Litter plays a key role in maintaining the nutrient cycle of the forest ecosystem. The dynamics of litter trace elements (TEs) can influence litter decomposition and biogeochemical cycling across plant and soil systems. However, our understanding of the biogeochemical cycle of TEs during litter decomposition remains limited. We investigated litter production, the concentrations and fluxes of needle litter TEs over 1 year, and the accumulation and release patterns of TEs at different elevations and canopy coverage during litter decomposition over 3.9 years for the Qinghai spruce in the Qilian Mountains. The concentrations and fluxes of TEs in the needle litter decreased in the following order: Zn > Ni > Cr > Cu > Pb > Co > Cd > Ag. TEs concentrations increased with decomposition time at different elevations, and Co, Cr, Cu, Ni, Pb, and Cd accumulated the fastest at 2850 m. Zn and Ag accumulated the fastest at 3450 and 3050 m, respectively. The fastest accumulation trends were for Co, Cu, Ni, Pb, Zn, Ag, and Cd concentrations at low canopy coverage. Cr accumulated the fastest at middle canopy coverage. The concentrations of Co, Cu, Pb, Zn, Ag, and Cd followed the trend of enrichment–release–enrichment, while Ni and Cr concentrations followed the trends of release–enrichment and sustained enrichment, respectively. Our study is important for an improved understanding of the TE cycle during litter decomposition. It provides theoretical support for healthy soil management and element cycling in the forest of the Qilian Mountains. [ABSTRACT FROM AUTHOR]

Current ecosystem models used to simulate global terrestrial carbon balance generally suggest that terrestrial landscapes are stable and mature, but terrestrial net primary productivity (NPP) data estimated without accounting for disturbances in species composition, environment, structure, and ecological characteristics will reduce the accuracy of the global carbon budget. Therefore, the steady-state assumption and neglect of elevation-related changes in forest NPP is a concern. The Qilian Mountains are located in continental climate zone, and vegetation is highly sensitive to climate change. We quantified aboveground biomass (AGB) and aboveground net primary productivity (ANPP) sequences at three elevations using field-collected tree rings of Picea crassifolia in Qilian Mountains of Northwest China. The results showed that (1) There were significant differences between AGB and ANPP at the three elevations, and the growth rate of AGB was the highest at the low elevation (55.99 t ha−1 10a−1). (2) There are differences in the response relationship between the ANPP and climate factors at the three elevations, and drought stress is the main climate signal affecting the change of ANPP. (3) Under the future climate scenario, drought stress intensifies, and the predicted decline trend of ANPP at the three elevations from mid-century to the end of this century is −0.025 t ha−1 10a−1, respectively; −0.022 t ha−1 10a−1; At −0.246 t ha−1 10a−1, the level of forest productivity was significantly degraded. The results reveal the elevation gradient differences in forest productivity levels and provide key information for studying the carbon sink potential of boreal forests. [ABSTRACT FROM AUTHOR]

Vegetation carbon sequestration in alpine areas of West China, such as the Qilian Mountains on the northeastern Tibetan Plateau, has been subject to long-term human intervention under a warming climate since the launch of the western development strategy (WDS) in 2000. However, the human impacts on vegetation carbon sequestration capacity during this period remain unclear. In this study, the magnitude and direction of human impacts on vegetation carbon sequestration capacity (defined as net primary production, NPP) were assessed by the deviation of remote-sensing–estimated actual NPP data from the simulated potential NPP. The potential value was derived from natural system coupling under the assumption that human activities ceased during the assessment period. The impacts of natural forces and historic human activities were then effectively exfoliated in our final assessment using a process-based IBISi model. The results indicate that the total actual vegetation carbon sequestration capacity in the Qilian Mountains has reduced compared with its potential value since the WDS launched. This reduction was mainly attributed to grazing in the grasslands. However, deforestation, mineral resource exploitation, and the construction of hydropower facilities have also caused a reduction in vegetation carbon sequestration capacity at the local scales. In contrast, forestry protections and afforestation, and agricultural activities associated with reclamation, cultivation, irrigation, and fertilization, have resulted in local increases in the vegetation carbon sequestration capacity in the corresponding forest lands, shrublands, and croplands. These findings highlight the importance of ecological protections for vegetation carbon sequestration and were expected to provide evidence to verify the improvement of ecological management and the increasing of carbon sinks in West China. [ABSTRACT FROM AUTHOR]

The subalpine shrub zone of the Qilian Mountains is an important water-retaining area, and it is crucial to clarify the processes of its hydrological cycle. Therefore, based on the stable isotope values of different water bodies in the subalpine shrub zone of the eastern Qilian Mountains from May to October 2019, the characteristics of δD and δ18O of different water bodies and their hydraulic relationships with each other were studied. The results showed that the stable isotope values of precipitation exhibited the largest fluctuations, while they were the most stable for groundwater. Plant transpiration was stronger than the evaporation of other water bodies. The stable isotope of precipitation was enriched in high temperature and low humidity environments. Isotopic values of plant and soil water were higher and more stable on the semi-sunny slope than on the semi-shady slope. According to the stable isotopes, there was a strong hydraulic relationship between the different water bodies in the study area, and precipitation was the ultimate source of all of them. Precipitation replenished soil water through infiltration. Part of the soil water was absorbed by plants, while the rest continued to infiltrate to replenish groundwater. Groundwater and precipitation replenished the river water. HIGHLIGHTS The stable isotopes of precipitation, soil water, plant water, river water, and groundwater can vary because of season and slope orientation.; Isotopic values of plant and soil water were higher and more stable on the semi-sunny slope than on the semi-shady slope.; Water lines and isotopic analysis were used to qualitatively determine replenishment relationships among different water bodies.;

Precipitation data is vital fundamental data for climate change. However, obtaining precise gauge-measured precipitation in high-altitude mountains is challenging, and the precipitation obtained from various gauge types at the same station may vary. To understand the differences in precipitation observations among the three commonly used gauges in China (Chinese Standard Precipitation Gauges (CSPG), Total Rain weighing Sensor (TRwS), and Geonor T-200B (T200B)) in high-altitude mountains and to recommend a stable and cost-effective weighing gauge, a precipitation intercomparison experiment was conducted at Hulu-1 station in the Qilian Mountains. The wind-induced error in measurement was corrected with the ‘universal’ transfer function recommended by the Word Meteorological Organization. The comparison results, adjusted for systematic errors, showed that the rain, snow and mixed precipitation of CSPG and TRwS equipped with the same octagonal vertical double fence shields (CSPGDF and TRwSDF) and single-Alter shields (CSPGs and TRwSs) were close, while the precipitation of Tretyakov-shielded T200B was notably higher than that of CSPGs and TRwSs. The average differences in annual and daily precipitation between CSPGDF and TRwSDF from 2017 to 2021 were 12.9 mm and 0.10 mm, respectively. The daily precipitation difference between CSPGs and TRwSs from April 2019–December 2021 was 0.10 mm, while the differences between T200Bs and CSPGs and TRwSs was 0.28 mm and 0.38 mm, respectively. The wind shield performance of Alter and Tretyakov was not much different at Hulu-1 site with low wind speed, thus the measurement principle of T200Bs was the primary cause of the high observations. Taking the corrected CSPGDF measurement as the standard, the dynamic loss of CSPGs was 17.6%, while that of CSPGUn was 55.6%, indicating that the single-Alter shield could effectively reduce the impact of wind on precipitation measurement. Considering the comparison results and the price difference of the instruments, it was recommended to use a single-Alter shielded TRwS gauge for precipitation observation in high-altitude mountains.

Study region: The Xiying River Basin is a typical inland mountainous watershed located in the Qilian Mountains. Study focus: This article reveals the change of runoff stable isotopes and their control mechanisms based on isotope data of different water bodies (precipitation, runoff, groundwater, and glacial snowmelt) in the Xiying River Basin from 2016 to 2021, combined with relevant meteorological observation data and the Normalized Vegetation Index (NDVI). New hydrological insights for the region: The results show that (1) meteorological factors control runoff isotope variations through controlling the evaporation process of runoff and the isotopic characteristics of recharge sources. (2) In areas with low vegetation cover, surface landscape features influence runoff isotopic composition by altering the isotopic characteristics of recharge sources. (3) In areas with high vegetation cover, surface vegetation cover affects runoff stable isotopes by controlling evapotranspiration processes. This study connects vegetation cover and runoff isotopes to explain the surface landscape control of runoff stable isotopes. It offers a more powerful reference for elucidating the factors influencing runoff isotopes in inland mountain watersheds.

The Qilian Mountains serve as significant ecological security barriers in the western region of China. Their continuous and stable water supply is essential for the sustainability of the human oasis in the Hexi Corridor, as well as for the maintenance of the desert ecosystem in the north. In the past three decades, land use in this area has changed significantly because of human activities, which has had a profound impact on water yield services. Based on the Water Yield module of the InVEST model, we evaluated the area and water yield of land use during 1990–––2020, and discussed the characteristics of water yield response to changes in land use. As a result of the study, it was found that in the Qilian Mountains during the period 1990–––2020: (1) the areas of swamp, unused land, medium coverage grassland, and woodland reduced, while the areas of high coverage grassland, low coverage grassland, cultivated land, construction land, glaciers, and water area increased, and each land use type exhibited a different degree of transformation. (2) In terms of total water yield, this declined by 1.09 × 108 m3, water yield of medium coverage grasslands, unused land, and swamp decreased, while water yield of other land uses increased, however, the responses to the change in water yield as a result of the change in land use were significant. (3) The areas with decreased water yield fall mainly within the high-altitude areas of the Qinghai Lake and Qaidam river watersheds, while the low-altitude areas were characterized by an increase in water yield. This study may provide decision-makers with guidance for protecting the ecosystem of the Qilian Mountains and developing a national park in the Qilian Mountains.

The Qilian Mountains (QLMs) encompass a diverse alpine grassland ecosystem undergoing notable changes due to global climate change. Understanding the driving forces behind these changes is crucial for effective regional vegetation restoration and management, particularly given the contrasting climatic conditions between the eastern and western regions of the QLMs. This study investigated the spatiotemporal evolution of grassland NDVI and the influence of 13 variables on NDVI changes in six distinct QLM sub-basins from 1990 to 2019 using Landsat data and the Geodetector model, respectively. Results revealed a consistent greening trend in all sub-basins, albeit with varying slopes. Notably, the Qinghai Lake basin exhibited a recent slowdown in NDVI, highlighting the need for enhanced vegetation restoration efforts, especially in permafrost-covered areas. Environmental factors affecting NDVI differed among basins. In the western QLMs, sunshine duration and relative humidity emerged as key factors influencing NDVI distribution, while in the eastern basins, altitude and air temperature played significant roles. This study underscored the importance of hydrothermal conditions, both horizontally and vertically, in shaping grassland NDVI. Other factors, such as vegetation types, soil characteristics, and permafrost degradation, also influenced NDVI, while slope and slope aspects had a limited impact. Furthermore, the research identified threshold-dependent responses of NDVI to the interaction of these factors. These findings emphasized the need to customize vegetation restoration strategies based on the specific environmental conditions of each basin within the QLMs. This nuanced understanding of the distinct driving characteristics between the eastern and western QLMs enables more effective and targeted approaches to restoring and managing grassland ecosystems in this region.

Tibet's Qilian Mountains (QM) include critical water conservation areas and important ecological barriers, which help maintain downstream inland river oasis stability. For decades, contemporaneous climatic and cryospheric variation has severely impacted QM's hydrological processes, challenging local water resource management and sustainable development. However, due to prevalent data and methodological limitations, QM research has primarily focused on runoff change at a basin scale. Spatial distributions and temporal changes in runoff subsequently remain unclear. Based on multi‐source data and the literature, we estimated that QM's mountain outlets generate approximately 15.671 km3 in total annual runoff, exhibiting a spatially decreasing pattern from northeast to southwest. Moreover, runoff distribution and trend variation at seasonal and annual scales depend upon the river replenishment source type. Beginning in the 1950s and 1960s, eastern rain‐fed rivers experienced a downward trend while those dominated by meltwater or simultaneously fed by multiple sources in its central and western regions experienced an upward trend. As an integrated product of mixed multi‐factor effects, runoff is regulated by temperature, precipitation, and cryospheric meltwater. Moreover, the main controlling runoff factors varied seasonally under different water source concentrations. Annually, precipitation was the main driver for runoff change in the eastern region while, correspondingly, temperature was in the western region where glaciers and the snow line boundary predominant. Besides, this study highlighted that the existing literature has significant limitations in understanding interactions among different cryospheric components and hydrologic process mechanisms when exploring the reasons for runoff variations, which needs further exploration in the future. Plain Language Summary: As a critical water conservation area and ecological security barrier in western China, the Qilian Mountains (QM) is a core region within the Silk Road Economic Belt. It is regarded as the "water tower" to inland rivers in the Hexi Corridor, the eastern margin of the Qaidam Basin desert, and upstream areas of the Yellow River, nurturing more than 5 million people. However, spatiotemporal patterns and driving factors of runoff variations under climate change conditions remain unclear. Based on multi‐source data and published literature, this study estimated that 15.671 km3 of total annual runoff was generated on the QM, which generally decreased from northeast to southwest. Although seasonal distributions of runoff in major rivers were similar, their annual runoff trends showed a substantial difference between the eastern (i.e., downward trend) and western (i.e., upward trend) regions. From east to center to west, river replenishment types changed from rainfall dominant to mixed replenishment/groundwater dominant to meltwater dominant, causing different sensitivities to temperature and precipitation among rivers. Currently, the main approaches exploring physical mechanisms of QM runoff are qualitative analyses. Comprehensive quantitative research that encompasses various cryospheric components is needed to enhance scientific understanding of hydrological processes in this region. Key Points: Average annual total river runoff on the Qilian Mountains was estimated at approximately 15.671 km3, decreasing from northeast to southwestA downward trend in annual runoff was observed in the eastern region, while an upward trend was observed in its central and western regionsRiver replenishment types changed from rainfall dominant (eastern) to mixed replenishment (central) to meltwater dominant (western) [ABSTRACT FROM AUTHOR]

The Qilian Mountains (QLMs) form an important ecological security barrier in western China and a priority area for biodiversity conservation. Potentilla parvifolia is a widespread species in the mid‐high altitudes of the QLMs and has continuously migrated to higher altitudes in recent years. Understanding the effects of P. parvifolia on microbial community characteristics is important for exploring future changes in soil biogeochemical processes in the QLMs. This study found that P. parvifolia has profound effects on the community structure and ecological functions of soil microorganisms. The stability and complexity of the root zone microbial co‐occurrence network were significantly higher than those of bare soils. There was a distinct altitudinal gradient in the effect of P. parvifolia on soil microbial community characteristics. At an elevation of 3204 m, P. parvifolia promoted the accumulation of carbon, nitrogen, and phosphorus and increased sucrase activity and soil C/N while significantly improving the community richness index of fungi (p <.05) compared with that of bacteria and the relative abundance of Ascomycota. The alpha diversity of fungi in the root zone soil of P. parvifolia was also significantly increased at 3550 m altitude. Furthermore, the community similarity distance matrix of fungi showed an evident separation at 3204 m. However, at an altitude of 3750 m, P. parvifolia mainly affected the bacterial community. Potentilla parvifolia increased the bacterial community richness. This is in agreement with the findings based on the functional prediction that P. parvifolia favors the growth and enrichment of denitrifying communities at 3550 and 3750 m. The results provide a scientific basis for predicting the evolutionary trends of the effects of P. parvifolia on soil microbial communities and functions and have important implications for ecological governance in the QLMs. [ABSTRACT FROM AUTHOR]

Quantitative assessments of the impacts of climate change and anthropogenic activities on runoff help us to better understand the mechanisms of hydrological processes. This study analyzed the dynamics of mountainous runoff in the upper reaches of the Shiyang River Basin (USRB) and its sub-catchments, and quantified the impacts of climate change and human activities on runoff using the improved double mass curve (IDMC) method, which comprehensively considers the effects of precipitation and evapotranspiration on runoff, instead of only considering precipitation as before. The results indicated that the annual runoff depth in the USRB showed a slightly increased trend from 1961 to 2018, and sub-catchments were increased in the west and decreased in the east. The seasonal distribution pattern of runoff depth in the USRB and its eight sub-catchments all showed the largest in summer, followed by autumn and spring, and the smallest in winter with an increasing trend. Quantitative assessment results using the IDMC method showed that the runoff change in the USRB is more significantly affected by climate change, however, considerable differences are evident in sub-catchments. This study further developed and improved the method of runoff attribution analysis conducted at watershed scale, and these results will contribute to the ecological protection and sustainable utilization of water resources in the USRB and similar regions. [ABSTRACT FROM AUTHOR]

Global warming is causing melting of glaciers, which is affecting socioeconomic development. It is essential to study the combined influence of changes in structures of glaciers on human well-being and socioeconomic systems. Herein, we considered Qilian Mountains as an example, quantified the regional socioeconomic benefits of glaciers and human well-being, and attempted to draw a correlation between glacier service value and human well-being. The findings of our study reveal that the value of glacier services in Qilian Mountains decreased from 1.84 × 1010 yuan in 1998 to 1.72 × 1010 yuan in 2018, with a spatial trend of circling down from the central region to the western and eastern regions. The distribution of human well-being showed an increasing trend, and a phenomenon of "low value central and western clustering, high value eastern sporadic distribution." There is an increasing degree of coordination between human well-being and glacier services value; the spatial distribution shows a decreasing trend from the west to the east, with differences in the nature of coordinated development in different regions at the same coordination stage being obvious. We analyzed the changes in glacier services value and their relationship with human well-being from both micro and macro perspectives to provide theoretical support for formulating management strategies for glacier resource conservation and improving the interface between glacier service evaluation results and government decision-making. [ABSTRACT FROM AUTHOR]

Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Scientifically evaluating the influence of ecological restoration projects on the water conservation function (WCF) of regional ecosystems is the foundation for formulating regional ecological restoration policies and optimizing and adjusting ecological restoration projects. In this paper, we considered fully the runoff generation and confluence process in the Qilian Mountains with the actual situation of the basin and re-rated the parameter Z to improve the simulation accuracy of InVEST model. On this basis, the impact of ecological restoration project on the WCF in the upper reaches of Shiyang River Basin (SRB) in the eastern part of Qilian Mountains was quantified. The results showed that, on the whole, the water conservation depth (WCD) of forest land was the largest (138.5 mm) and that of cultivated land was the smallest (24.78 mm), while the water conservation coefficient of forest land was also the largest (93.36%) and that of unused land was the smallest (16.67%). From 1986 to 2018, the WCD showed an increasing trend in the upper reaches of SRB, among them, the WCD in the western tributaries increased faster than that in the eastern tributaries from 1986 to 2000. The significantly increased areas were mainly distributed in the middle reaches of the western tributaries and the river source areas of the eastern tributaries, while the significantly decreased areas were mainly distributed in the river source areas of the western tributaries and the cultivated land expansion area in the middle reaches of the eastern tributaries. From 2000 to 2018, the WCD of the eastern tributaries increased more than that of the western tributaries. The significantly increased areas were mainly distributed in the four eastern tributaries, and the significantly decreased areas were scattered in the middle and lower reaches of each tributary. From 1986 to 2000, the overall influence of land use change on the increase in WCD was negative, while the influence of climate and land use change on the increase in water conservation were both positive from 2000 to 2018. The influence of land use change on WCD was different in different tributaries. Among them, that of the western tributaries (except the Dongda River) was positive in two different periods, while that of the eastern tributaries (except the Xiying River) was changed from negative to positive. The implementation of ecological restoration project was one of the main reasons for the improvement of WCF in Qilian Mountains from 2000 to 2018, with a contribution of 9.04%. In the future, the protection and restoration of decreased areas of WCF should be strengthened, and the Z value determined in this paper is expected to be applied in the arid inland river basins of northwest China. [ABSTRACT FROM AUTHOR]

The Qilian Mountains (QMs) act as the "water tower" of the Hexi Corridors, playing an important role in the regional ecosystem security and economic development. Therefore, it is of great significance to understand the spatiotemporal characteristics of precipitation in the QMs. This study evaluated the performance of 21 models of phase 6 of the Coupled Model Intercomparison Project (CMIP6) from 1959 to 1988 based on ERA5 and in situ datasets. In addition, the precipitation changing trend from 2015 to 2100 was projected according to four shared socioeconomic pathways (SSPs): namely, SSP126, SSP245, SSP370, and SSP585. The results have shown the following: (1) all CMIP6 models could reflect the same precipitation changing trend, based on the observed datasets (−2.01 mm·10a−1), which was slightly lower than that of ERA5 (2.82 mm·10a−1). Multi-mode ensemble averaging (MME) showed that the projected precipitation-change trend of the four scenarios was 5.73, 9.15, 12.23, and 16.14 mm·10a−1, respectively. (2) The MME and ERA5 showed the same precipitation spatial pattern. Also, during the period 1959–1988, the MME in spring, summer, autumn and winter was 130.07, 224.62, 95.96, and 29.07 mm, respectively, and that of ERA5 was 98.57, 280.77, 96.85, and 22.64 mm, respectively. The largest precipitation difference in summer was because of strong convection and variable circulation. (3) From 2015 to 2100, the snow-to-rain ratio was between 0.1 and 1.1, and the snow-to-rain ratio climate tendency rate was concentrated in the range of −10~0.1 mm·10a−1. Both of these passed the significance test (p < 0.05). The projected rainfall of all four SSPs all showed an increasing trend with values of 6.20, 11.31, 5.64, and 20.41 mm·10a−1, respectively. The snowfall of the four SSPs all showed a decreasing trend with values of 0.42, 2.18, 3.34, and 4.17 mm·10a−1, respectively. [ABSTRACT FROM AUTHOR]

Studying the spatial and temporal distribution of soil organic carbon (SOC) content in high-altitude mountainous areas and its correlation with soil nutrients provides a basis for understanding soil carbon stocks and the factors affecting the local carbon cycle. Based on soil samples collected from a semi-sunny slope and semi-shady slope in the subalpine shrub zone of the eastern Qilian Mountains from May to October 2019, we studied the temporal and spatial changes in SOC and soil available nutrients and their relationships. The results showed that SOC content and soil nutrients were greater on the semi-shady slope than on the semi-sunny slope during the growing season and decreased with an increase in soil depth in different slope directions, showing obvious surface aggregation. The soil available nitrogen (SAN) content was consistent with the SOC content and exhibited greater synchronization. SOC was significantly positively correlated with soil available nutrients in the study area during the whole growing season. However, the correlation between SOC and soil nutrients varied among the different soil layers and slope orientations. The SOC content was more obviously correlated with the SAN content in the soil layer at a depth of 30–40 cm (r = 0.67, p < 0.05) on the semi-shady slope. The SOC content was more obviously correlated with soil-available phosphorus (SAP) content in the soil layer at a depth of 30–40 cm (r = 0.57) on the semi-sunny slop. The SOC content was more obviously correlated with the SAP content in the soil layer at a depth of 60–70 cm (r = 0.55) and with the soil-available potassium (SAK) content in the soil layer at a depth of 70–80 cm (r = 0.84) on the semi-sunny slope. [ABSTRACT FROM AUTHOR]

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Surface runoff is a major component of the hydrological cycle, and it is essential for supporting the ecosystem services provided by grassland and forest ecosystems. It is of practical importance to understand the mechanisms and the dynamic processes of runoff in a river’s basin, and in this study, we focused on the restored montane Pailugou Basin in the Qilian Mountains, Gansu Province, China, since its water status is extremely important for the large arid area and local economies therein. Our purpose was to determine the annual variation in the surface runoff in the Pailugou Basin because it is important to understand the influence of climate fluctuations on surface water resources and the economy of the basin. In addition, little is known about the annual variations in precipitation and runoff in this region of the world. Daily atmospheric precipitation, air temperature and runoff data from 2000 to 2019 were analyzed by the calculation of the uneven annual distribution of surface runoff, the calculation of the complete adjustment coefficient, and the vector accumulation expressed by the concentration degree. We also used the cumulative anomaly approach to determine the interannual variation trend of runoff, while the change trend was quantified by the sliding average method. Finally, we used the Mann–Kendall mutation test method and regression analysis to establish the time-series trend for precipitation and runoff and to determine the period of abrupt runoff changes. The results indicated concentrated and positive distributions of surface runoff on an annual basis, with a small degree of dispersion, and an explicit concentration of extreme flows. The relative variation ranges exhibited a decreasing trend, and the distribution of the surface runoff gradually was uniform over the year. The runoff was highest from July to September (85% of the annual total). We also determined that annual surface runoff in the basin fluctuated over the 20-year period but showed an overall increasing trend, increasing by 3.94 × 105 m3, with an average increase rate of 0.42 × 105 m3 every ten years. From 2005 to 2014, the annual runoff and the proportion of runoff in the flood season (July to September) to the annual runoff fluctuated greatly. The correlation between the runoff and precipitation was significant (r = 0.839, p < 0.05), whereas the correlation between air temperature and surface runoff was low (r = 0.421, p < 0.05).

To understand how the soil microbial community structure responds to vegetation restoration in alpine mining areas, this study specifically examines the grassland ecosystem in the Qianmalong mining area of the Qilian Mountains after five years of artificial restoration. High-throughput sequencing methods were employed to analyze soil bacteria and fungi microbial characteristics in diverse grassland communities. Combined with modifications in vegetation diversity as well as soil physicochemical properties, the impact of vegetation restoration on soil microbiome diversity in this alpine mining area was investigated. The findings indicated that the dominant plants were Cyperus rotundus, Carex spp., and Elymus nutans. As the extent of the grassland’s restoration increased, the number of plant species, importance values, and plant community diversity showed an increasing trend. The plant functional groups were mainly dominated by Cyperaceae, followed by Poaceae. Plant height, density, plant cover, frequency, and aboveground biomass showed an increasing trend, and soil water content (SWC) increased. While soil pH and soil electrical conductivity (EC) exhibited a declining trend, available phosphorus (AP), total phosphorus (TP), total nitrogen (TN), nitrate nitrogen (NO3-N), soil organic carbon (SOC), and soil water content (SWC) showed an increasing trend. The dominant bacterial communities were Actinobacteriota, Proteobacteria, Acidobacteriota, Chloroflexi, Firmicutes, and Gemmatimonadota, while the dominant fungal communities were Ascomycota, Mortierellomycota, Basidiomycota, unclassified_k_Fungi, and Glomeromycota. Significant differences were detected within soil microbial community composition among different degrees of restoration grasslands, with bacteria generally dominating over fungi. SWC, TP, and TN were found to be the main soil physicochemical factors affecting the distribution of soil bacterial communities’ structure; however, SOC, TN, and NO3-N were the primary factors influencing the soil distribution of fungal communities. The results of this study indicate that different degrees of vegetation restoration in alpine mining areas can significantly affect soil bacterial and fungal communities, and the degree of restoration has varying effects on the soil bacteria and fungi community structure in alpine mining areas.

Abstract The Qilian Mountains (QLMs) form an important ecological security barrier in western China and a priority area for biodiversity conservation. Potentilla parvifolia is a widespread species in the mid‐high altitudes of the QLMs and has continuously migrated to higher altitudes in recent years. Understanding the effects of P. parvifolia on microbial community characteristics is important for exploring future changes in soil biogeochemical processes in the QLMs. This study found that P. parvifolia has profound effects on the community structure and ecological functions of soil microorganisms. The stability and complexity of the root zone microbial co‐occurrence network were significantly higher than those of bare soils. There was a distinct altitudinal gradient in the effect of P. parvifolia on soil microbial community characteristics. At an elevation of 3204 m, P. parvifolia promoted the accumulation of carbon, nitrogen, and phosphorus and increased sucrase activity and soil C/N while significantly improving the community richness index of fungi (p

Research into leaf traits, especially carbon (C), nitrogen (N), and phosphorus (P), are essential for understanding the nutrient uptake strategies and ecosystem functions, such as the rates of photosynthesis, transpiration, and nutrient intake in plants. However, seasonal patterns of leaf C:N:P stoichiometry in arid and semiarid forest ecosystems remain unclear. In this study, temporal scale monitoring was conducted on four conifer species (Picea wilsonii, Pinus tabuliformis, Picea crassifolia, and Juniperus przewalskii) within the Qilian Mountains to determine the seasonal patterns of leaf C:N:P stoichiometry and their driving forces. The seasonal patterns of the leaf N and P contents were asynchronous among the species. The C content and C:N and C:P ratios in the leaves in Tulugou (relatively wet and fertile) were lower than those in Langchaigou (extremely infertile and dry), whereas the N and P contents in the leaves displayed an inverse pattern (p

Soil water plays a key role in vegetation growth and ecological stability in cold regions. The soil water sources in the Qilian Mountains of the northeastern Tibetan Plateau have been quantified based on stable isotope data (δ2H and δ18O) of 1913 samples. The results indicated that δ18O of soil water ranged from ˗14.13–11.21‰, with an average of ˗6.78‰, and on a spatial scale, it increased gradually from the southeast to the northwest, where it became more positive. The stable isotopes of soil water are affected by evaporation, leading to a lower slope and interception of the evaporation line: δ2H = 3.23 δ18O–32.51 (R2 = 0.71, p