基于综合指标的潼湖平塘湖泊生态系统健康评价

Ecosystem health assessment of TonghuPingtang Lake based on comprehensive indicator method

潼湖平塘是广东省典型的内陆淡水湖泊湿地,是区域内重要的生态屏障和生态功能区,科学评估其健康状况可以更好地指导潼湖平塘生态修复。本文基于国内外湖泊健康评价经验,构建了包含1个目标层、4个准则层(“盆”、“水”、“生物”和“社会服务功能”)和16个指标层的湖泊生态环境健康评价体系。将层次分析法和综合评估法相结合,计算湖泊健康得分,获得了潼湖平塘水生态健康状况。评估结果显示:8项指标处于非常健康状态(80~100分),3项指标处于健康状态(60~80分),防洪达标率处于亚健康状态(40~60分),湖泊营养状态、鱼类保有指数、大型水生植物覆盖度和浮游植物密度等4项指标处于不健康状态(20~40分),总体评估表明潼湖平塘整体处于亚健康状态,属于生态功能受损的三类湖泊。建议从外源污染物源端监管、污染水体和底泥治理、外来入侵物种防治、蓄滞洪区防洪工程建设等方面开展水污染防治工作。评价结果能够为湖泊的开发利用和保护修复提供基础数据和决策依据。

TonghuPingtang is a typical inland freshwater lake wetland in Guangdong Province.It is also an important ecological barrier and ecological function area in the region.Scientific assessment of the lake health status can bet-ter guide the ecological restoration of TonghuPingtang Lake.Based on the experience of lake health evaluation at home and abroad,a lake ecological environment health evaluation system was constructed consisting of a target lay-er,four criteria layers of basin,water,biology and social service function,and 16 indicator layers.Combining hierar-chy analysis with comprehensive assessment,the water ecological health status of TonghuPingtang is obtained by calculating the lake health assessment scores.The results of assessment demonstrate that eight indicators were in a very healthy state with the scores variable within 80~100;three indicators were in a healthy state with the scores variable within 60~80;the flood control compliance rate was in a sub-health state with the scores variable within 40~60;four indicators including lake trophic status,fish retention index,aquatic macrophyte coverage and phyto-plankton density were in an unhealthy state with the scores variable within 20~40.The overall assessment indicates that TonghuPingtang Lake was in a sub-health state,with ecological function damaged and categorized to Class III lake.Four water pollution prevention and control measures were suggested including source-end monitoring and ad-ministration of exogenous pollutants,remediation of contaminated water and sediment,prevention and control of in-vasive alien species,and construction of flood control projects in flood detention area.The assessment results can be basic data and decision basis for the development,utilization,protection and restoration of lakes.