阳宗海生态环境需水量及环境功能解析

阳宗海是典型的高原湖泊,为实现阳宗海流域的生态功能与水资源最优管理,通过环境背景调查及湖泊生态环境需水量功能计算模型,从湖泊蒸发需水量、湖泊自身存在需水量、生物栖息地需水量、湖泊净化需水量、湖泊渗漏需水量、沿湖绿地需水量6个方面,对阳宗海生态环境需水量进行了研究。结果表明:在20%、50%、80%三种保证率条件下,湖泊净化需水量占阳宗海生态环境需水量的95%左右,说明阳宗海生态环境需水主要用于满足湖泊稀释自净;从湖泊环境功能角度分析,即阳宗海目前主要环境功能为稀释净化其入湖污染物,不符合其目标环境功能。同时,由阳宗海生态环境需水量与其对应蓄水量可知,阳宗海流域只有少量的可供水量,附近居民区及各种产业的发展,降低了整个湖泊的可供水量。

Analysis on Eco-environmental Water Demand and Environmental Functions of Yangzonghai Lake

In order to achieve the optimal management of ecological functions and water resources of Yangzonghai Lake,a typical plateau lake,the eco-environmental water demand of Yangzonghai Lake was calculated from the six aspects of water demand for evaporation,water demand for itself being,water demand for biological habitat,water demand for pollutants cleaning,leakage water amount and water demand for lake-swamp green belt by way of environmental background investigation and the calculation model of lake ecological environment water demand.The calculation results showed that under the reliability of 20%,50%,80%,the percentages of the water demand for pollutants cleaning were 95%,which indicated that the eco-environmental water demand of Yangzonghai Lake was mainly used for dilution of self-purification.From the angle of the lake environmental functions,that the dilution and self-purification considered as the current main environmental function of the Yangzonghai Lake did not meet the criterion of environmental functions.At the same time,there was only a small quantity of water available considering the Yangzonghai Lake eco-environmental water demand and corresponding water volume,while the development including the nearby residential areas and a variety of industry reduced the amount of water available for the whole lake.