Characteristics Analysis of Incoming Runoff and Sediment Process and Sediment Accumulation of Danjiangkou Reservoir

Danjiangkou reservoir make up of Hanjiang river reservoir area and Danjiang river reservoir area which is parallel connection reservoir.According to incoming runoff and sediment process data of average per year,characteristics of incoming runoff and sediment process and sediment accumulation of reservoir was analyzed.Results showed that incoming runoff and sediment process of reservoir area distributing and annual distribution aren't very much uniform,Hanjiang river reservoir area and flood season is possessed of absolute majority.Sediment accumulation of main stream reservoir area is approximately 85%,branch stream is approximately 15%.Sediment accumulation of Hanjiang river reservoir in the main stream reservoir area is approximately 70% of the whole reservoir,its sediment accumulation is most.Sediment grain mostly structure of perennial backwater region is clay,which is possessed of 81.9%～100%.Variable backwater region is most of sand,which is possessed of 46.8%～98%.Longitudinal section sediment accumulation in the Hanjiang river main stream reservoir is perennial backwater region more and variable backwater region less,reservoir capacity loss is middle more and both ends less.Transverse sediment accumulation is mostly which lies in the slope bottomland.In the end,sediment accumulation change of reservoir was predicted.