Effects of Up-Slope Runoff and Sediment on Down-Slope Erosion Process

摘要

Soil erosion at hilly-gully region of the Loess Plateau has obviously erosion vertical zones from watershed boundary to gully edge, i.e., sheet zone dominated, rill zone dominated, and shallow gully zone dominated. To quantify effects of up-slope runoff and sediment on down-slope detachment, deposition and transport processes as well as mechanisms can provide importantly scientific bases for establishing erosion prediction model. Because of this, A dual-box system (one is test box and the other is feeder box) is used to quantify impacts of up-lope runoff and sediment on detachment, deposition and transport processes at down-slope sheet and rill erosion dominated zone. The results showed the additional sediment delivery ( S ) at down-slope caused by up-slope runoff increases with an increase of rainfall intensity or runoff from up-slope, and with a decrease of sediment concentration in up-slope runoff. In addition, rill erosion and soil bulk density have great effects on the additional sediment delivery (S).