三峡水库蓄水运用前后坝下游水沙输移特性研究  

Research on water and sediment transport characteristics downstream the Three Gorges reservoir before and after its impoundment

作　　者：姚仕明[1,2] 卢金友[1] 

机构地区：[1]长江科学院,武汉430010 [2]清华大学水利水电系,北京100084

出　　处：《水力发电学报》2011年第3期117-123,共7页Journal of Hydroelectric Engineering

基　　金：国家科技支撑计划课题(2006BAB05B03);中国博士后科学基金(20070410065;200801085);中国科学院知识创新工程重大项目(KZCX1-YW-08-01-02)

摘　　要：根据三峡工程坝下游主要水文站的水沙实测资料,较系统地分析了包括三峡水库蓄水运用以来近50余年的坝下游干流与洞庭湖水系、鄱阳湖水系及支流汉江皇庄站的水沙输移特性。结果表明,三峡水库蓄水运用前,坝下游河湖水系总体表现为淤积,以洞庭湖淤积为最严重,洞庭湖四水及三口入湖沙量沿时间呈减小趋势,三口入湖沙量减小尤为明显,汉江因干支流水库、水土保持等工程的建设,输沙量减小超过1亿t,鄱阳湖出口湖口站径流量呈增加趋势,泥沙输移量则有所减少,五河年均来沙量大于湖口入江沙量;三峡水库蓄水运用以来,坝下游干流河道总体表现为沿程冲刷,洞庭湖区泥沙沉积量与沉积率均大幅度下降,汉江皇庄站自20世纪80年代以来年均输沙量变化不大,年均不到0.1亿t,湖口站年均输沙量大于五河来沙量。研究成果可供三峡工程坝下游河湖演变与治理研究等参考。This paper presents a systematic analysis on the water and sediment transport characteristics of the Yangtze reaches downstream the Three Gorges reservoir over the past 50 years,including the Yangtze mainstream,Dongting Lake＇s river systems,Poyang Lake＇s river systems and Huangzhuang hydrological station on the Yangtze＇s tributary Hanjiang River.This analysis is based on the water and sediment data measured at the major hydrological stations in these reaches and focuses on the influences of reservoir storage.Results show that before the impoundment,an overall tendency of deposition occurred in all the rivers and lakes downstream the dam,particularly,the most serious in Dongting Lake,while the time variations of the sediment loads in the four rivers and the loads at the three inlets into Dongting Lake assumed a decreasing tendency that was most obvious at the three inlets.During this period,the sediment discharge in Hanjiang River was reduced by over 100×106 tons due to the construction of reservoirs on the mainstream and tributaries as well as the works of soil and water conservation.Though the runoff of Hukou hydrological station at the Poyang Lake＇s outlet tended to be increased,the sediment discharge there was reduced to some extent,and the annual average of total sediment discharge into the Yangtze by the five rivers exceeded that at the Hukou station.Since the impoundment of Three Gorges reservoir,an overall tendency of streamwise progressive erosion has occurred in the main river channel downstream the dam,and the deposition volume and depositing rate in the Dongting Lake area have been greatly reduced.Since 1980s the change in the annual average sediment runoff at the Huangzhuang station has been as little as less than 10×106 tons,while the annual average of total sediment discharge by the five rivers has fallen below that at the Hukou station.These results would serve as a reference for studies of the evolution and regulation of rivers and lakes in the lower Yangtze reaches.

关 键 词：河流动力学 水沙输移 资料分析 三峡工程 

分 类 号：TV143[水利工程—水力学及河流动力学]