洞庭湖的泥沙问题及其治理设想

Sedimentation in Dongting Lake and the Tentative Plan for Regulation

洞庭湖在历史上湖泊面积曾达6000km^2,以后由于人工围垦和泥沙的淤积,使洞庭湖逐渐淤积萎缩,现仅剩2690km^2,给长江中、下游和湖区的防洪、航运及工农业生产带来极大影响.本文从江湖关系出发,着重阐述分析了洞庭湖泥沙淤积发展规律和趋势,并提出了在四口分流中,仅保留松滋口一口分流的治理设想,既可减少进入洞庭湖的泥沙,又有利于集中分流,提高水流输沙能力.

The Dongting Lake has now shrinked to one only with an area of 2690 km2 from 6000 km2 in the history which responds significant influence on the flood prevention, navigation, industry and agriculture in the regions of the lake and the middle and lower reach of the Yangtze. There are four outlet diversions to the Dongting Lake. The main cause of the shrinking is the reclamation of land from lake and sedimentation which depends chiefly on inflow and sediment from the four diversions. This paper analyses for the most part the processes and the tendency of the sediment deposition in the view of the relation between the Yangtze and the Dongting lake and suggests that all the diversions except Songzi Diversion to be blocked so as to reduce inflow sediment to Dongting Lake converging the diversed flow and increasing the sediment transport capacity.