Variation of sediment transport and flood disaster in the middle reach of Yangtze River

In this article, the historical and recent variation of sediment transport and deposition in the middle reach of Yangtze River is comprehensively analyzed and the causes of flood disasters in this area is concluded. The typical feature of sediment transport in this area is the sediment depositing in the main river channel, which triggers the more serious flood disasters not only in the main river channel but also in Dongting Lake. With the aggravation of human activities in upper and middle stream, the situation will be worse. The key measure to prevent disasters is to try to reduce the amount of sediment by 1.8×10 8t.To reach this goal, the long term strategy is to recover natural vegetation and construct reservoirs in the upper reach, and the short term is to properly allocate the sediment deposition location. Sediment discharge from the Three Gorge Project after its operation and the corresponding river bed erosion course in the downstream reach reflects the legitimacy of the conclusion of this article, which suggests to reduce the sediment by 1.8×10 8t.