Abstract

This contribution reviews available evidence of recent changes in the sediment loads of the world’s rivers and identifies the key drivers of such change. Land clearance, land use change and other facets of catchment disturbance, soil conservation and sediment control programmes and dam construction are shown to have resulted in significant recent changes in the sediment loads of many world rivers. Some rivers have been characterized by significant increases in sediment load whereas others show significant decreases. Interpretation of the resulting trends requires consideration of aggregation and storage and buffering effects within a river basin, such that the downstream response of a river may not clearly reflect the changes occurring in the upstream basin and in the loads of tributary rivers. Although the available data are insufficient to produce a reliable assessment of the impact of recent changes in the sediment loads of the world’s rivers on global land-ocean sediment transfer, an attempt has been made to estimate the likely changes in this transfer and the net effect of increasing and decreasing sediment loads.

Keywords: Suspended sediment loads, trends, world rivers, anthropogenic impacts, reservoir trapping, buffering effects, global land-ocean sediment transfer