Spatial-temporal evolution of soil erosion in a typical watershed of the Loess Plateau
Soil erosion is influenced by various factors,such as land use and climate change.The Wangmaogou watershed,as a typical area for soil and water conservation in the hilly and gully regions of the Loess Plateau,has implemented a series of measures since the 20th century,including the Grain for Green Project.This study evaluated the spatial and temporal evolution characteristics of soil erosion intensity in the watershed in the years of 2010,2015,and 2020 using the CSLE model.It also studied the situation of land use/cover change(LUCC)to analyze the spatial distribution patterns of land use and the responses of soil erosion in different time periods,thereby verifying the effectiveness of the soil and water conservation measures.The results revealed that from 2010 to 2020,the annual average soil erosion modulus in the study area decreased by 0.11 t hm-2 a-1,indicating a slight improvement in overall soil erosion conditions.However,the proportion of slight erosion decreased by 5.56％,while severe erosion increased by 4.02％,with the higher erosion zone mainly distributed in the northern,central,and northwestern parts of the watershed.Compared to the year 2010,soil erosion conditions in the watershed were greatly relieved in 2015 due to the decrease of rainfall and restoration of vegetation,but rebounded in 2020 resulting from the extreme rainfall events and declining vegetation cover quality.From 2010 to 2020,there were significant conversions between grassland and farmland in the northern and northeastern parts of the watershed.The decline in grassland quality resulted in a higher average soil erosion modulus compared to farmland,at 13.69 t hm-2 a-1 and 12.99 t hm-2 a-1,respectively.This study would contribute to figuring out the relationship between soil erosion in typical small watersheds of the Loess Plateau,extreme climatic events,and land use changes,providing scientific data support for future efforts to improve soil and water conservation benefits and mitigate soil erosion risks.
万方数据
维普
