ESTIMATION OF TEMPORAL VARIATION OF SEDIMENT YIELD FROM SMALL CATCHMENTS THROUGH THE KINEMATIC METHOD

A method is proposed for estimation of temporal variation of the sedim ent yield for single storm-events in small catchments. The kinematic w ave equations are used for simulation of overland flow whereas continu ity 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 collect ed data of 12 experimental catchments from varying climates and rangin g in size from 0.002 km(2) to 92.5 km(2) are used for calibration and verification of the proposed method. The observed sediment yields duri ng the storm events studied hererin varied from about 0.003 tonnes to 800 tonnes. The method developed in the present study depends on calib ration against a record of past conditions. Therefore, it can not be u sed directly to predict the future changes in catchment land use or cl imate. However, the present method can be used for estimation of sedim ent yield in other such ungauged catchments which have similar hydro-m eteorological conditions and for which other information are available . (C) 1997 Elsevier Science B.V.