Abstract:

The sedimentation of Dongting Lake affects the flood control, water resource and water eco-environment of the Yangtze River and the Dongting Lake. On the basis of previous researches on general sedimentation of Dongting Lake, we analyzed the sediment transport and deposition distribution in each region of the Lake. It has practical significance for the comprehensive regional management of Dongting Lake. By analyzing the measured hydrology, sediment and terrain data in different regions of the Lake, we found that sediment deposition of Dongting Lake has been decreasing since 1950s. Annual sedimentation of Dongting Lake is less than 10% of that before the impounding of Three Gorges Reservoir. Regional deposition was not in lakes, but mainly in flood courses. The shrinkage of west Dongting Lake has been in its later stage, of which sediment deposition has greatly reduced. The east and south Dongting Lake were silted during flood season, and scoured in non-flood season without considering the interval sediment conditions.

Key words: Dongting Lake, sediment transport, sediment deposition, temporal and spatial distribution