SEDIMENT DELIVERY PROCESSES AT BASIN-SCALE

Since eroded sediments are produced from different sources distributed throughout a basin, sediment delivery processes at basin scale have t o be modelled by a spatially distributed approach. In this paper a new theoretically based relationship is proposed for evaluating the sedim ent delivery ratio, SDR(i), of each morphological unit, i, into which a basin is divided. Then, using the sediment balance equation written for the basin outlet, a relationship between the basin sediment delive ry ratio, SDR(w) and the SDR(i) is deduced. This relationship is shown to be independent of the soil erosion model used. Finally, a morpholo gical criterion for estimating a coefficient, beta, is proposed.