Variations and effects on water and sediment in the Jingjiang River three outlets and Dongting Lake

According to the 50 years information of the water and sediment in the three outlets of the Jingjang River and Dongting Lake,the four aspects such as the variation of the divided flow and the sediment by the three outlets of the Jingjiang River,the variation of the water and sediment in the input and output of the Dongting lake water area and the volume in the Dongting Lake and the river water level in the afflux section have been analyzed.From the analysis on the long series data,it was obviously decreased the the divided flow and sediment in the three outlets of the Jingjiang River,for the Ouchi outlet since 1950s.In addition,there were some reducing tendency for the water and sediment in the input and output of the Dongting River.The water erea and the volume in the Dongting River had the increasing tendency since the 90's intermediate stages.Comparing with before cutting off,the water level in Chenglingji was 1.8m higher on the high water level,and 2m higher on the low water leve.