Impact of Land Use Change on Watershed Soil Erosion Under Different Development Scenarios

Abstract

Watershed soil erosion is an important cause of soil degradation. The impact of land use change on erosion is an important aspect of human activity affecting soil resources. In this study, the response of soil erosion to land use patterns was tested under different social and economic development scenarios in the Wujiang River basin, China. Land use data for 2000, 2010, and 2015 were input into the Land Change Modeler to analyze historical land use changes and estimate the land uses in 2050 under different scenarios. The three development scenarios were as follows: business-as-usual (BAU; S1), economy-centered development (S2), and green development (S3). The Soil and Water Assessment Tool model was used to simulate sediment yield and load from basin slopes and river channels, respectively, under the three different land use patterns in 2050. Under S1 and S2, the degree of soil erosion was increased because of forestland reduction, and some sub-basins became intensely eroded. Under S3, the watershed was slightly to lightly eroded, and soil erosion was minimized. The results indicate that green development scenarios can not only effectively reduce sediment transport in the river basin but also reduce the amount of sedimentation in downstream reservoirs. Based on the three land use patterns, this study's projections of the response of erosion to land use changes under different social and economic development scenarios can inform planning for watershed management and relevant soil and water conservation measures.