蒙古高原土壤水分时空演变格局演变特征分析OA北大核心CSTPCD

[Objective]The aims of this study are to analyze the spatiotemporal differentiation and variation of soil moisture in the Mongolian Plateau,and to quantify the influence of key driving factors,so as to provide a theoretical basis for regional ecological restoration and sustainable ecosystem development.[Methods]Based on the ERA5 soil moisture data,the spatial differentiation and changes of soil moisture at the depth of 0-289 cm in the Mongolian Plateau from 2000 to 2020 were revealed,and the impacts of different environ-mental factors such as meteorology,normalized difference vegetation index(NDVI),terrestrial water stor-age anomaly(TWSA),soil texture,and topography were further quantified.[Results](1)From 2000 to 2020,soil moisture in the Mongolian Plateau displayed a distribution characteristic of high level in the north-east and low level in the southwest.From shallow to deep layers,the soil moisture presented a change trend of no significant increase(0-28 cm),no significant decrease(28-100 cm)and significant decrease(100-289 cm).(2)There were 58.5%,76.7%,91.3%,and 98.8% of the regions with Hurst index greater than 0.5.The change trend of soil moisture in most regions in the future will be the same as in the past.The drying of soil moisture in the northwestern Mongolian Plateau and central Inner Mongolia may further aggra-vate.(3)Temperature,TWSA,precipitation,and NDVI were the dominant environmental factors affecting the spatial distribution of soil moisture.Most of the factor interactions showed a bi-factor enhancement effect,and the spatial differentiation of soil moisture in the Mongolian Plateau was the result of the joint action of multiple factors.(4)The changes in surface and subsurface soil moisture were mainly positively affected by precipitation,and the dominant control areas accounted for 98.7% and 94.8% of the total vegetated area of the plateau,respectively.The main control areas of precipitation and TWSA on soil moisture at the layer of 28-100 cm concentrated in areas covered by forestland and grassland,with the dominant area accounting for 38.7% and 38.8%,respectively.The decrease in TWSA was the main driving force leading to the drying of soil moisture in the layer of 100-289 cm,with the main dominant area accounting for 58.6% .The increase in water consumption by vegetation and the increase in temperature dom-inantly controlled the changes in soil moisture in layer of 100-289 cm in 16.2% and 14.8% of the plateau,respectively.[Conclusion]The spatial and temporal differentiation and change patterns of soil moisture are obvious,and the main driving forces of soil moisture at each depth are different.This is of great significance to the ecological restoration of the Mongolian Plateau and the sustainable development of the ecosystem.In the future,the impact of human activities on it should be analyzed in depth.