Dynamic Variation of Wetland Types in Dongting Lake and Poyang Lake Under the Background of Three Gorges Project
Dongting Lake and Poyang Lake wetland are two natural lake wetlands in the middle and lower reaches of the Yangtze River,which have important ecological service functions.This paper summarizes the dynamic variation law of wetland types and hydrological regime of the two lakes during the dry season under the background of the operation of the Three Gorges Project,and analyzes the influence of the change of hydrological regime upon the dynamic change of wetland types of the two lakes.The results show that the types and patterns of wetlands in the two lakes changed significantly.The area of water and sediment decreased from 2003 to 2009,and the vegetation expanded.After 2009,the area of water began to increase.After the operation of the Three Gorges Project,the variation trend of the hydrological regime in the two lakes is the same,the amount of water and sediment into the lake decrease,the sediment depo-sition slows down obviously,and the water level of the lake decreases during the dry season.The change of hydrological regime in the two lakes has an impact on the type and pattern of wetlands in the two lakes.In 2003,the first experimental impoundment of the Three Gorges Project significantly reduced the water lev-el in the dry season of the two lakes,resulting in the reduction of water area and exposure of beaches in the two lakes.In 2009,the water level began to rise in the dry season after the medium and small flood dis-patching,and the water area showed an increasing trend,which had a great impact on the habitat of winte-ring waterfowl in the two lakes.The analysis results provide a theoretical basis for the protection and eco-logical restoration of the two lakes wetland under the background of the Three Gorges Project.
three gorges projecthydrological regimeDongting lake wetlandPoyang lake wetlanddy-namic changes of wetland types
万方数据
维普
