洞庭湖区湿地综合资源管理与复合生态系统建设

Research on Comprehensive Management and Construction of Multiecosystem in Dongting Lake Region.

通过对洞庭湖区湿地衰退原因与特征的分析，提出合理开发湿地资源必须强化湿地整体管理，控制湿地开发规模，适度退田还湖还蓄（洪区），调整农业布局与种植制度，走集约持续发展之路，建设复合高效湿地生态系统；进行适应洪涝灾害发生规律的避洪、耐渍型生态设计，建立适应浅水水体、湖洲和低湖渍害田的复合高效生态工程模式。

The wetland in Dongting Lake Region is the largest lacustrine in China,which is 8.77105 hm2. It can be divided into three classes: open fresh water,seasonal flooded basin and flats,shallow fresh marshes. Due to the neglecting of environmental management and ecological construction, soil and water erosion in the upper and middle reaches of Yangtze, the deposition of sediment in lakes, reclaiming land from lake marshes on large scale, irrigation distribution of agriculture and improper cropping system at high water level zones, the regulating capacity for floods was descending, flood stage was risen and flood was prolonged. With developing wetland on large scale, it has made some harmful influence on the ecological environment. In order to utilize and protect wetland rationally,the following measures should be taken: (1)To control the scale of wetland reclamation and making great efforts to construct highefficiency multiecosystem. The reclamation without storing floodwater should be readjusted into new land use with flood storage project. The settlements should be moved to small townships. Cultivation and planning can be carried out on the land in normal years. The land could be used for storing waters when catastrophic flood takes place. Some fields which are hindrance to flood flow should be merged properly for fish culture.(2)To adjust allocation of agriculture and cropping system.(3)To breed and popularize submergencetolerant rice types.(4)To strengthen wetland comprehensive management. According to the principles of ecological engineering and previous practices, nine comprehensive utilization models which are suitable to open fresh waters, seasonal flooded basins and flats as well as shallow fresh marshes have been put forward.