黄土丘陵区典型流域土壤侵蚀时空演变特征及其驱动机制:以祖厉河为例OA北大核心CSTPCD

The loess hilly area in China is ecologically fragile,and the soil erosion situation is grim.Accurately assessing the spatial and temporal variation of soil erosion in loess hilly areas and deep exploration of the underlying driving mechanisms can provide important theoretical support for local soil and water conservation.This study investigated the Zuli River Basin as the research objective,based on the RUSLE soil erosion assessment model,combining the transfer matrix,spatial autocorrelation,geographic detector,and other geostatistical analysis tools,and evaluated the spatial distribution pattern of the soil erosion modulus and driving force between 2000 and 2020.The results showed that 1)the soil erosion intensity class in the Zuili River Basin from 2000 to 2020 was dominated by slight and mild,and the average soil erosion modulus during the 2020,a period decreased from 1.299×103 t∙km-2∙a-1 to 635 t∙km-2∙a-1,i.e.,the erosion intensity class was reduced from mild erosion to slight erosion.2)From 2000 to 2010,approximately 1.968×103 square kilometers of the soil erosion area developed in a benign direction,accounting for 18.4%of the total watershed area.From 2010 to 2020,the soil erosion area increased by approximately 3.089×103 square kilometers,accounting for 28.9%of the total watershed area,and the effects of soil and water erosion control were remarkable.3)There is an obvious spatial aggregation of soil erosion in the Zuli River Basin,in which the"high-high"aggregation area is mainly distributed in the junction of Huining County and Anding District,and the mountainous hills in the northwest of the basin,and the"low-low"aggregation area is mainly distributed in the basin,and the"low-low"aggregation area is mainly distributed in the basin.The"high-high"gathering area is mainly distributed in the northern and southwestern coastal plain area of the watershed,and the area of the"high-high"and"low-low"gathering types has decreased annually over the past 20 years.The area of the"high-high"and"low-low"aggregation types has decreased annually over the past 20 years.4)Precipitation is the primary factor that affects soil erosion.Terraces play an important role in improving soil erosion,and the joint action of natural factors and human activities has shaped the spatial distribution patterns of soil erosion.In the future,soil and water conservation management should focus on at-risk areas with low temperature and drought,high altitude,steep terrain,low vegetation cover,a high degree of soil sand pulverization,and few terraced fields.