洞庭湖水污染环境经济损害初步评价

运用水污染损失率为基础的评价方法，对洞庭湖水体使用功能损害程度进行评价表明：洞庭湖水已不适合作饮用和游泳水源（重损害，损失率分别为70％和58％）；主要污染物来自营养物质，且以氮为限制性因素。洞庭湖功能损害的根源在于泥沙。洞庭湖作为人体非直接饮用的旅游娱乐用水已受到严重威胁（中损害，损失率22％）。作为养殖、农业灌溉以及一般居住环境用水尚好（损失率＜8％）。综合损害程度为中损害（损失率42％），若洞庭湖水不再用作饮用水源和游泳场，其综合水质是可接受的（微损害，损失率降为3％）。

Preliminary assessment of economic loss caused by water pollution in Dongting lake

Based on economic loss rate of water due to pollut ion,the damage extent of applied functions of water in Dongting lake is assessed .Results show that water in Dongting lake has not been suitable for serving as a water source for drinking and swimming(seriously damaged,with loss rate of 70% and 58% respectively),and main pollutents come from nutrient,taking nitrogen as a restrictive factor.The root of functional damage of water in Dongting lake is sedimentation.As a sort of water used for tourism and recreation,not for drinkin g,water in the lake has also been affected by pollution (moderately damaged,with loss rate of 22%),but as a sort of water used for aquaculture,irrigation and re sidential environment,it is still in good condition (with loss rate less then 8% ).Its comprehensive damage extent is moderate (with loss rete of 42%).If water in Dong-ting lake is no longer used for drinking and swimming,its comprehensive quality is acceptable (slightly damaged,with loss rate reduced to 3%).