Spatial and temporal variations of soil erosion in the Fenhe River Basin over the past 20 years

Abstract: Background The Fenhe River Basin is situated in the central reaches of the Yellow River Basin, where soil erosion is a significant issue. Despite the notable advancements in soil erosion control in the Fenhe River Basin in recent years, the prevalence of severe erosion in certain regions persists, posing a significant constraint on the sustainable development of socio-economic and ecological systems. Methods Accordingly, this paper estimated the spatial pattern of soil erosion in the Fenhe River Basin from 2000 to 2023 based on the CSLE model, the application of Geographic Information Evolution (GEO) mapping facilitated the analysis of spatial and temporal variability patterns of soil erosion in the watershed over the past 20 years, and the coupled mapping method was utilised to explore the drivers of spatial and temporal changes in soil erosion using land cover. Results The findings revealed that the soil erosion intensity in the Fenhe River Basin in 2000, 2010 and 2023 was predominantly characterised by slight erosion. And the soil erosion intensity showed a trend of improvement and then intensification, and the transformation of light erosion into slight erosion in the basin was the main reason for the improvement of soil erosion in the basin, but the significant increase in the area of light erosion and moderate erosion from 2010 to 2023 resulted in the part of the area where erosion was intensified; the area of soil erosion of cropland was dominated by slight erosion, forestry was dominated by slight and light erosion, while grassland was dominated by light erosion. The area of soil erosion improvement under the influence of land cover change is slightly larger than the area of deterioration, and about 76.47% of the land cover change has an improvement effect on soil erosion, and the increase of grassland reduction of cropland is the main source of improvement area. Conclusions The increase of soil erosion level in the Fen River basin is closely related to extreme rainfall and topography, human activities and ecological policies. Therefore, continued attention to the conversion of grassland and cropland on slopes in the basin and the strengthening of soil and water conservation measures on cropland are the focus of the following soil and water conservation projects in the Fen River Basin.