长江中下游水沙与河床冲淤变化特性研究  

Research on water-sediment variation and deposition-erosion in middle and lower Yangtze River

作　　者：许全喜 朱玲玲 袁晶 

机构地区：[1]长江水利委员会水文局,湖北武汉430010

出　　处：《人民长江》2013年第23期16-21,共6页Yangtze River

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);国家自然科学基金"具有二元结构河岸的弯道崩岸机理与数值模拟研究"(51079103);水沙科学与水利水电工程清华大学国家重点实验室资助项目(2013-ky-1)

摘　　要：利用长江干、支流水文和河道地形实测资料,研究了三峡工程运用前后坝下游水沙输移特性与河湖泥沙冲淤的时空格局和变化特征。结果表明:①三峡工程建成运行后,长江中游洪峰流量减小,中水时间延长,汛后退水时间缩短,干流输沙量大幅减少,泥沙来源发生新变化,荆江三口分流分沙量继续减少;②长江中游干流河势总体稳定,但河床沿程纵向冲刷强度与三峡水库运用前相比明显增大,且冲刷强度和发展速度均大于原预测值;③荆江三口洪道由蓄水前的淤积转为冲刷;④洞庭湖淤积速度大为减缓,鄱阳湖受河道采砂等影响,总体由淤积转为冲刷;⑤长江中游河、湖泥沙冲淤格局发生调整,三峡水库蓄水前长江中游河、湖呈淤积状态,蓄水后则呈冲刷状态。Based on the field hydrological data including Yangtze River main stream and tributaries, and the measured topo- graphic data of the middle Yangtze River, Dongting Lake and Poyang Lake, the characteristics of water and sediment transpor- ting, the patterns and variation of sediment erosion and deposition in the middle Yangtze River before and after the Three Gorges Reservoir operation are studied. The analysis leads to several conclusions, including： （ 1 ） The annual runoff process is changed, such as the discharge of flood peak is cut down, the duration of medium discharge prolongs and the recession time is shorten. Not only sediment discharge in the middle Yangtze River reduces sharply, but also the source of sediment is undergoing a change. The water and sediment discharge diverted from Jingjiang reach to Dongting Lake continues to fall; （2） The regime of the middle Yangtze River is steady in general, but the longitudinal erosion intensity of river bed increases obviously, both of the erosion in- tensity and rate are greater than the predicted values ; （3） The three flood diversion channels that connect the Jingjiang reach and Dongting Lake were in deposition before the operation of TGP, but they began to be scoured after 2003 ; （4） The annual sediment siltation of Dongting Lake decreases greatly while Poyang Lake changes from siltation to scouring; （5） The overall patterns of sediment erosion and deposition in the middle Yangtze River and two connected lakes were adjusted from siltation to scouring in general.

关 键 词：水沙变化 泥沙冲淤格局 长江中下游 三峡工程 

分 类 号：TV152[水利工程—水力学及河流动力学]