Abstract:In order to analyze the change and driving mechanism of erosion and sediment yield in the hillside area, this paper applied SWAT model to simulate sediment yield in Shouchang River Basin of Jiande City, Zhejiang Province, and calculated the landscape metrics based on Fragstats 4.2 for land use data in different years. The sediment yields in the basin were analyzed, the effects of slope, slope length, elevation, drainage area, rainfall, and landscape pattern on soil and sediment yield were discussed, and the principal components analysis was carried out. The main results were as follows:(1) The SWAT model had good applicability in the Shouchang River basin, R2, NSE and PBIAS all met the simulation and ensured the accuracy of the simulation results. (2) The maximum sediment yield of the entire Shouchang River basin from 1980 to 2010 was less than 500 t/(km2·a), and the soil erosion intensity was slight and the soil erosion retention ability was good. (3) The contribution rates of four principal components of topographic factor, landscape diversity factor, landscape shape factor, and rain intensity factor to sediment yield were 51.48%, 18.51%, 10.70%, and 6.94%, respectively, and topographic factor was the main factor affecting soil erosion and sediment yield. (4) There was a significant correlation between the landscape metrics and the sediment yield, and the landscape metrics had a significant impact on the sediment yield. In the future land-use planning, the landscape characteristics should be effectively considered to improve the soil erosion in the basin.