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The Qinghai–Tibet Plateau (QTP) has an important function in ensuring the water ecological security of China, even Asia, and the soil water storage of alpine grassland is an important part of the ecosystem water. Grassland degradation directly affects the soil water storage capacity. However, the impact of degradation on specific soil storage capacity, especially alpine shrubs, is rarely studied. Here, we chose two plots of alpine non-degraded shrub and degraded shrub, using the automatic soil moisture monitoring system to study the change process of soil moisture storage, and then adopted the boosted regression tree (BRT) model to quantitatively evaluate the relative influence of environmental variables on soil water storage. Our results show: (1) The soil water storage in the growing season (May–September) is higher than that in the non-growing season (January–April and October–December), and the soil water storage reaches its highest in mid-July. (2) During the growing season, the 100 cm soil temperature was the most important factor affecting the seasonal variation in soil water storage, accounting for 51% of the total variation. During the non-growing season, the 40 cm soil temperature was the most important factor affecting the variation in soil water storage, accounting for 80% of the total variation. (3) The soil water storage of non-degraded Potentilla fruticosa shrub meadow increased by 6–25%, compared with degraded grassland shrub meadow during growing-season. (4) Various meteorological factors have a weak impact on soil water storage. [ABSTRACT FROM AUTHOR]

• Dynamics of grassland ecosystems vulnerability to climate change were evaluated over the Qilian Mountains. • Patterns of change in grassland ecosystems vulnerability under different environmental gradients were explored. • Spatial distributions of grassland ecosystems vulnerability were mainly determined by exposure. • Climate, elevation, and slope gradients together influenced the degree of grassland ecosystems vulnerability. With climate warming and frequent extreme weather events, the structure and function of grassland ecosystems have been significantly altered. The Qilian Mountains are a wet island, serving as an important ecological barrier in China and central Asia. It is highly sensitive and prone to climate change, yet the vulnerability of grasslands to climate variability in this region remains unclear. In this study, based a NDVI dataset and meteorological data, we evaluated the relative vulnerability of grassland ecosystems to short-term climate variability by combining three indices: exposure, sensitivity, and resilience, and explored its relationship with water use efficiency (WUE). The results show that the spatial distribution patterns of grassland vulnerability in the Qilian Mountains from 2000 to 2018 were largely determined by exposure, and sensitivity is positively correlated with exposure and negatively correlated with resilience. The vulnerability of alpine meadow and alpine steppe is higher than that of temperate typical steppe and temperate desert steppe. Climate and topography gradients together affect the degree of grassland vulnerability. Grasslands with higher vulnerability are mainly found at medium elevation (3200–4000 m) area, where the topography is flat. The northern grasslands are primarily influenced by temperature, while the western and southern parts are mainly affected by precipitation. Alpine meadow and alpine steppe are more vulnerable to temperature and temperate desert steppe is more vulnerable to changes in precipitation. The higher the vulnerability, the lower the WUE of the grasslands. This study provides a reference for assessing the impact of climate change on grassland ecosystems and developing grassland vegetation management strategies. [ABSTRACT FROM AUTHOR]

• Dynamics of grassland ecosystems vulnerability to climate change were evaluated over the Qilian Mountains. • Patterns of change in grassland ecosystems vulnerability under different environmental gradients were explored. • Spatial distributions of grassland ecosystems vulnerability were mainly determined by exposure. • Climate, elevation, and slope gradients together influenced the degree of grassland ecosystems vulnerability. With climate warming and frequent extreme weather events, the structure and function of grassland ecosystems have been significantly altered. The Qilian Mountains are a wet island, serving as an important ecological barrier in China and central Asia. It is highly sensitive and prone to climate change, yet the vulnerability of grasslands to climate variability in this region remains unclear. In this study, based a NDVI dataset and meteorological data, we evaluated the relative vulnerability of grassland ecosystems to short-term climate variability by combining three indices: exposure, sensitivity, and resilience, and explored its relationship with water use efficiency (WUE). The results show that the spatial distribution patterns of grassland vulnerability in the Qilian Mountains from 2000 to 2018 were largely determined by exposure, and sensitivity is positively correlated with exposure and negatively correlated with resilience. The vulnerability of alpine meadow and alpine steppe is higher than that of temperate typical steppe and temperate desert steppe. Climate and topography gradients together affect the degree of grassland vulnerability. Grasslands with higher vulnerability are mainly found at medium elevation (3200–4000 m) area, where the topography is flat. The northern grasslands are primarily influenced by temperature, while the western and southern parts are mainly affected by precipitation. Alpine meadow and alpine steppe are more vulnerable to temperature and temperate desert steppe is more vulnerable to changes in precipitation. The higher the vulnerability, the lower the WUE of the grasslands. This study provides a reference for assessing the impact of climate change on grassland ecosystems and developing grassland vegetation management strategies. [ABSTRACT FROM AUTHOR]