Landslide of Surface Layer on the Slope and Estimation of Basin Sediment Yield

摘要

Through various rainstorm tests, the erosion processes of a slope was observed and the impacts of various topographic features, soil composition and vegetation on sediment yield were analyzed. The result indicated: (1) the excess rain is the main reason of the soil erosion of bare lands; and the sediment yield is related to the accumulated precipitation; (2) the sharp increase of soil pore water pressure is the instrinsic force to cause the soil dilapidation of surface layer, whereas the falling soil flow becomes the root of sudden increase of basin sediment yield. Finally, the relationship among the basin sediment yield, precipitation characteristics and basin characters, was analyzed, and the proposed formulation was vertified by the field data of sediment yield in Gushanchuan Basin.