长江上游水沙变化分析

Analysis on Change of Water flow and Sediment in Upstream of Yangtze River

初步分析了长江上游屏山站、北碚站以及宜昌站近50年来的水沙变化趋势。分析结果表明:长江上游年均径流量变化比较平缓,总体上波动不大,近几年有增加的趋势;输沙量总体逐渐减少。屏山站1980-2000年输沙量偏高,2001-2005年输沙量则有减少的趋势;北碚站水沙变化趋势完全一致,但输沙量减幅更甚;宜昌站80年代以来输沙量一直呈下降趋势,尤其是90年代以来输沙量急剧减少。

The trends of water flow and sediment changes at three hydrographic stations （Pingshan, Beibei and Yichang） in recent 50 years are analysed. The analytic results show as follows： The variation of average annual runoff of the upstream of the Yangtze River is not distinct, while the sediment delivery rate has been reduced gradually. The sediment discharge at Pinshan Hydrological Station was rather high from 1980 to 2000, but presented a decreasing trend from 2001 to 2005. The change trend of water flow and sediment at Beibei Hydrological Station was completely consistent, while the sediment delivery rate was reduced very obvious. The sediment outflow at Yichang Hydrological Station has presented the downward trend since 1980s, specially was reduced severely since 1990s.