近50年来长江水沙变化规律研究  

Characteristics of Flow and Sediment Change in Yangtze River in Recent 50 Years

作　　者：许全喜 童辉 

机构地区：[1]长江水利委员会水文局,湖北武汉430010

出　　处：《水文》2012年第5期38-47,76,共11页Journal of China Hydrology

基　　金：国家"973"项目课题"长江中游通江湖泊江湖关系演变过程与机制"(2012CB417001);水利部公益性行业科研专项"梯级水库运用对长江中游水沙与冲淤影响研究"(200901003)

摘　　要：较为系统地研究了近50年来长江流域不同河段、不同时段的水沙变化特性。从多年平均情况来看，长江上游水沙异源、不平衡现象十分突出，干流石鼓至宜昌沙量沿程增大，宜昌以下干流河道输沙量沿程减小。悬沙中值粒径也沿程变细：1991～2002年长江干流各站径流量变化不大，输沙量明显减少；2003～2010年长江上游来沙减小趋势仍然持续，加之三峡水库蓄水拦沙作用，坝下游输沙量大幅减小，悬移质泥沙粒径沿程变粗，至监利站粗沙量已基本恢复到蓄水前的水平。三峡水库蓄水运用后，长江中下游径流年内分配、泥沙来源和地区组成均发生新变化；荆江三口分流分沙量继续减小，洞庭湖湖区淤积减缓：三峡工程蓄水运用不仅改变了长江上游与中下游的冲淤环境，而且也进一步促进了长江中游江湖泥沙分配格局的调整。In this paper, the flow and sediment change characteristics in the Yangtze River Basin in recent 50 years was studied. Seeing from the long-term average runoff and sediment transportation, the flow and sediment distribution is very unbalance in the upstream of the Yangtze River. For example, from Shigu to Yichang, the sediment discharge is increasing along the reach, and in the downstream of the Yichang station, it reduces along the reach, and the nominal diameter of the suspended load thin down accordingly. From 1991 to 2002, the runoff at the control stations has almost no change, but the sediment discharge reduced evidently. From 2003 to 2010, the reducing trend of the sediment discharge from the upstream of the Yangtze River is still continuing, and together with the function of the Three Gorges Reservoir （TGR）, the sediment discharge downstream the dam reduced with large extent, and accordingly, the grain size of the suspended load coarsen along the reach, up to Jianli station, the coarse sand capacity has almost resumed to the level that before the impoundment of the TGR. After the impoundment of the TGR, new change occurred to the runoff distribution, sediment source and composition in the middle and downstream of the Yangtze River. The flow and sediment diversion capacity continues to decrease, and the sediment deposition velocity in the Dongtinghu Lake slows down. The TGR not only changed the erosion and deposition environment, but also accelerate the adjustment of sediment distribution situation in the middle and downstream of the Yangtze river.

关 键 词：水沙变化 三峡工程 长江流域 

分 类 号：TV142[水利工程—水力学及河流动力学]