根据１９５６－１９９５年洞庭湖水文泥沙原型观测和地形测绘等翔实资料， 运用输沙量法和地形法对洞庭湖（湖区各站）冲淤变化进行了认真的统计分析分析，结果表明，洞庭湖来水量以四水为主，占 ５７． ８％ ；来沙量以四口为主，占 ７９． ５％，多年平均沉积率为 ７４． ０％，出湖仅占２６．０％；淤积量及出湖水沙量随着四口分流分沙比的减小而减少．洞庭湖年淤积量为 ４９． ３ × １０~８ｔ，其中四口水系约１７． ３ × １０~８ｔ，占３５．１％，天然湖泊约３２．０×１０~８ｔ，占６４．９％；天然湖泊年均淤积量、淤积体积、淤积厚度分别为０．８×１０~８ｔ、０．５７×１０~８ｍ~３、０．０１８ｍ洞庭湖水系中，松滋河的东西两支、资水尾闾、草尾河、西洞庭湖两个出口等测站河床呈冲刷趋势，其他水系湖泊呈淤积状态洞庭湖出口河道从１９８８年起显冲刷迹象，指示洞庭湖的衰亡呈缓解状态 Based on the informative data of hydrologic and sediment prototypes and topographic surveys of Dongting Lake from 1956 to 1995, this paper makes a careful statistical analysis of erosion and sedimentation in Dongting Lake (stations in the lake area) using the sediment yield and topography methods. The results show that Dongting Lake Lake water to four main water, accounting for 57. 8%; the amount of sediment to four, accounting for 79. 5%, multi-year average deposition rate of 74. 0%, out of the lake only 26.0%; siltation and outflow of water and sediment with the reduction of the diversion ratio of four to reduce. Dongting Lake deposition of 49 years. 3 × 10 ~ 8t, of which four about 17 water system. 3 × 10 ~ 8t, accounting for 35.1% and natural lakes about 32.0 × 10 ~ 8t, accounting for 64.9%. The annual average sediment, sediment volume and sediment thickness of natural lakes are 0.8 × 10 ~ 8t , 0.57 × 10 ~ 8m ~ 3, 0.018m Dongting Lake water system, the Songzi River two east and west water tail, Caowei River, West Dongting Lake two exit stations such as riverbed erosion trends, other water systems Lacustrine siltation of the state of Dongting Lake export channel since 1988 showed signs of erosion, indicating the decline of Dongting Lake was eased state