Current changes of sediment yields in the upper Yangtze River and its two biggest tributaries, China

摘要

The sediment yield of the Upper Yangtze River (Yichan) showed no visible trend in change, while its two largest tributaries showed different variations in sediment yield: with a decrease in Jialing River and an increase in the Jinsha River during the period from the 1950s to the 1990s. The lack of obvious change in sediment yield in the Upper Yangtze River (Yichan) during the cited period may be due to the offsetting consequences of the sediment yield changes in the two biggest tributaries during this period. It was apparent that the current decreasing trend in sediment yield in the Jialing River was due to the effects of revegetation, soil conservation and water conservancy efforts on reducing river sediment. Land degradation, engineering and channel activities were responsible for the increase in trend in sediment yield of the Jinsha River.