Slope Length and Surface Residue Influences on Runoff and Erosion

Runoff rate, runoff velocity , sediment concentration and soil loss rate of rills or overland flow channels were measured at selected downslope distances on plots with varying rates of sorghum and soybean residue, runoff rate, runoff velocity and soil loss rate usually increased with downslope distance. In general, the presence of greater amounts of crop residue reduced sediment concentration and soil loss rate along the entire slope length. Substantial variations in runoff rate, runoff velocity, sediment concentration and soil loss rate were found with downslope distance on some residue treatments.