Length-slope factors for the Revised Universal Soil Loss Equation: Simplified method of estimation

Abstract

The combined length-slope (LS) factor in the Universal Soil Loss Equation (USLE) is a measure of the sediment transport capacity of overland flow. A dimensionless sediment transport capacity index that is a non-linear function of specific discharge and slope was derived by considering the transport capacity limiting sediment flux in the Hairsine-Rose, WEPP, and catchment evolution erosion theories. For a two-dimensional hillslope, the index is equivalent to the combined LS factors in the Revised Universal Soil Loss Equation (RUSLE), but it is simpler to use arid conceptually easier to understand. A major advantage of the index is that it can be easily extended to three dimensional terrain.