Impact of "returning farmland to lake" works on ecological environment of Dongting lake

Through analysis of influencing factors on ecological environment of Dongting area,the impact of returning farmland to lake works is predicted and it is concluded that returning farmland to lake can increase flood discharge and storage capacity of Dongting lake,improving local climate and water quality,it will be favorable to the protection of biological diversity and control of epidemic schistosomiasis.The implementation of the works will increase the flood release capacity of the Dongting by 10% plus.In extraordinary flood years,the area will increase 1 343 km\+2 due to the operation of flood storage polders,and plus the present natural area of 2 625 km\+2 the area will reach 968 km\+2,closing to the natural area in 1950 s.In the meantime,the construction of the works and towns for the relocatees will need some lands,destroy surface vegetation and cause soil-water losses.The water and soil pollution in resettlement area may happen for insufficient or delayed construction of environmental infrastructures and uneffective treatment of 3 wastes from township enterprises and civil sewage and garbage.The countermeasures and suggestions for the ecological environment protection in area are suggested.