湿地水环境健康评价方法及案例分析

水环境健康是湿地生态系统健康的基础.从水环境状态健康和过程健康两方面对水环境健康进行评价研究,其中水环境状态健康主要由水文和水质条件体现,水环境过程健康主要由水环境弹性、稳定性和恢复力体现.基于以上理论,并以西溪湿地公园作为案例,利用该区2009年3月～2010年3月的水环境月监测数据对水环境健康进行分析.结果表明,①西溪湿地水环境健康季节性变化明显,其中,冬季水环境健康指数最低(37.35),处于不健康状态,夏季水环境健康指数最高(46.36),处于亚健康状态;②西溪湿地公园中水塘和河溪水环境健康程度各异,总体而言,水塘水环境健康程度优于河溪水环境,水塘水环境健康指数为42.72,河溪水环境健康指数为37.99;③西溪湿地公园的水环境整体处于亚健康状态,水环境健康指数为53.80.由此可见,冬季改善河溪水环境是提高西溪湿地公园水环境健康的有效途径.

A Quantitative Method and Case Analysis for Assessing Water Health

Water is the basis of wetland, the degree of water health directly determines the function of wetland ecosystem. The theory and method of water health were established in the study. Water health included both water status health and water process health. Water status health was reflected by hydrologic condition and water quality. Water process health was calculated by water elasticity, water stability and resilience. Xixi Wetland Park was taken as the case study. The results indicated that: 1 Seasonal variations of water health were apparent in Xixi Wetland. Water health index was the highest (46.36) and stayed under the sub-health condition in summer. In contrast, water health index was the lowest (37.35) and unhealth in winter; 2the degrees of water health were obviously different between ponds and creeks. Water health index in ponds was 42.72, which was higher than that of creeks (37.99); 3 Water in Xixi Wetland Park was sub-health with 53.80 as its water health index. Based on the result of study, to enhance water health of creeks in winter is an effective measure to improve water health in Xixi Wetland Park.