云南洱海的生态保护及可持续利用对策

Ecological Protection and Sustainable Utilization of Erhai Lake,Yunnan

由于湖区经济发展和人口压力的增加,致使洱海出现了富营养化进程加剧、湖泊水位降低、湖滨带生境恶化、生物资源过度开发等一系列的生态环境问题.2002年洱海入湖污染负荷量CODCr为3008t.a-1,总磷为137.31t.a-1,总氮为1426.35t.a-1,其营养盐负荷总磷和总氮均已超过洱海中营养水平下的环境容量.洱海已处在一个关键的敏感的营养状态转型时期,形势十分严峻,为此提出明确洱海主导功能,注重城市化进程中的产业结构和产业布局的优化调整,建立洱海湖滨带保护区,加强旅游污染控制,适当调整洱海水资源调度运行方式,并通过污水收集与处理工程、主要入湖河流生态修复工程、生态农业建设及农村环境改善工程、湖泊生态修复工程、流域水土保持工程等措施,保护和改善洱海水环境.

Economic development and increase of population pressure have caused a series of ecological environmental problems of Erhaj Lake. These problems include：① Quickening of eutrophication process, ②Decrease of water level and water resources, ③Habitat deterioration of lakeside zone, and ④Overfishing and slow depletion of aboriginal fish. Pollutant loading of Erhai Lake is as follows： CODcr 3008t·a^-1, TP 137.31t·a^-1, TN 1 426.35t·a^-1 According to the me.strophic target of water quality, loading of nitrogen and phosphorus is far above environmental capacity of Erhai Lake. Erhai Lake is now in a pivotal and hypersensitive period of trophic states change, and the position is very critical. Therefore, some countermeasures to solve the problems are presented as follows： ① Defining the dominant functions of Erhai Lake,② Paying attention to the adjustment of the industrial structure and distribution in the course of urbanization, ③Setting up lakeside zone reserve, ④Strengthening the control of tourism pollution, ⑤Properly adjusting the water level of Erhai Lake, and ⑥Some ecological engineering measures for water resources protection in the basin should be taken through collecting and treating of urban sewages, ecological rehabilitating of the main inflowing rivers, constructing of ecological agricultures and improving of rural environment, ecological restoring of aquatic ecosystem, and soil and water conservation.