The Tendency of River Pattern Variation in the Lower Jingjiang River after Completion of the Three Gorges Project

After completion of the Three Gorges Project,a long time erosion will occur in the middle and lower reaches of Yangtze River,and the characteristics of river channel will be changed obviously.Wheather the original river pattern witl be maintained or not in these reaches,especially in the reach of Lower Jingjiang River,it is very important for flood control and navigation.In this paper,based on the research of fluvial process for meandering reach in the downstream of Danjiangkou Reservoir on the Hanjiang River,and for the variation of meandering reaches of Lower Jingjiang River after the practice of cut\|off project,the tendency and effective factors of river pattern variation in the Lower Jingjiang River after the impounding of Three Gorges Reservoir have been studied.The obtained conclusions are that:after compeltion of the Three Gorges Poject in the Lower Jingjiang River the unnecessary slope will be balanced by the reduction of water level difference,and the original meandering river pattern will be kept,although the meandering degree could be reduced slightly.