Evaluation of spatial distribution of soil erosion and sediment yield for a small watershed of the Loess Plateau by coupling MIKE-SHE with MUSLE

By making use of the runoff total and two-dimension discharge to estimate the rainfall-runoff factor of R, the coupling of MIKE-SHE with MUSLE was established, and the raster-based distribution of sediment yield for a small watershed was evaluated. It was found that both sloping field and residential area accounts for 44% and 34% of the total sediment yield, respectively. While, in terms of land forms, the gully slope contributes most of the total sediment yield, with the contribution as high as 68%. In general, it was indicated that 73% of the watershed could be classified as no rill erosion, whilst around 17% of area, especially for the area of gully slope, was of severe soil erosion rate. The identified pattern of erosion rate was generally agreed with the fact that the watershed was well vegetation covered, and the erosion on the gully slope was severe. It was suggested that, to estimate the total sediment yield of the watershed by coupling MIKE-SHE with MUSLE, it is necessary to take into account the procedure of mass erosion.