Changes in sediment yield of the Yellow River basin of China during the Holocene

This research reconstructs the changes in sediment yield of the Yellow River based mainly on a large number of 14C dates collected from the literature. The total volume of sediment yield of the basin during the Holocene is estimated to be 8.0×1012 tons. The annual sediment yield had an increasing trend over the Holocene from 0.68, 0.72, 0.79 to 1.01×109 tons over each 2500-year period from the early Holocene to the present. The changes in sediment yield are ascribed to both natural and anthropogenic reasons, in which the latter became important in the late Holocene. The mean rate of increase in natural sediment yield throughout the Holocene is estimated to be about 0.027×106 ton/year, and the natural annual sediment yield is projected to be 0.95×109 tons at the present. The increasing trend of natural sediment yield is reasoned to be the consequence of evolution of landforms, enhanced by tectonic movement and climatic change in the Loess Plateau, the principal sediment source of the river, towards a condition favorable to soil erosion. Comparing the estimated annual natural sediment yield with the current annual sediment load of 1.6×109 tons of the river, it is clear that human activities have augmented natural soil erosion by about 41% in the Yellow River basin. Furthermore, an estimate of the overall pattern of anthropogenic sediment yield shows an accelerated increasing trend, which is approximately correspondent with that of population in the Loess Plateau area.