Estimation of temporal variation of sediment yield from small catchments through the kinematic method

Abstract

Abstract A method is proposed for estimation of temporal variation of the sediment yield for single storm-events in small catchments. The kinematic wave equations are used for simulation of overland flow whereas continuity equation for sediment and expressions for sediment detachment and transport are used to compute the sediment yield. The method is based on numerical solution of these equations through a non-uniform spatial grid formed by time-area segments of the catchment. Carefully collected data of 12 experimental catchments from varying climates and ranging in size from 0.002 km2 to 92.5 km2 are used for calibration and verification of the proposed method. The observed sediment yields during the storm events studied hererin varied from about 0.003 tonnes to 800 tonnes. The method developed in the present study depends on calibration against a record of past conditions. Therefore, it can not be used directly to predict the future changes in catchment land use or climate. However, the present method can be used for estimation of sediment yield in other such ungauged catchments which have similar hydro-meteorological conditions and for which other information are available.