滇池草海水质变化趋势和特征污染物分析

Variation Trend of Water Quality and Analysis of Specific Pollutants of Caohai Lakeof Dianchi Lake

根据滇池草海2002—2011年的年均值水质监测数据、《地表水环境质量标准》和《滇池水环境质量地方评价规定》,运用综合水质指数法（WQI）计算得到综合水质指数,结合滇池治理工程,对草海10年来水质变化趋势进行分析。结果显示：1第一类重金属指标水质评价优良,2004—2007年,草海的第一类项目水质呈现下降趋势,2007年达到10年来最差情况。第二类分类指数为72~92,评价为严重污染,不安全级别。2009年水质最差,第二类污染物指数成为WQI的贡献值,是草海的主要污染物。第三类分类指数为3~32,水质优良,水质安全程度为安全级。2滇池水质波动的主要因素是富营养类污染物,特征污染物是总磷和总氮。

Water quality index （WQI） was adopted to evaluate the water quality of CaohaiLakeof Dianchi Lake u- sing the 10 years monitoring data of Caohai Lake in Dianchi lake from 2002 to 201 lon the basis of ＂Environmental Quality Standard for Surface Water （ GB3838 - 2002） ＂ and ＂Dianchi Lake Local Evaluation Regulations on Water Environmental quality＂. The results showed that the heavy metal index indicated a good water quality. The index decreased from 2004 to 2007. The water quality in terms of heavy metal was worst in 2007 during the ten years. The second kind of index scored from 72 to 92, which showed a serious pollution and unsecure status. The worst water quality occurred in the year of 2009. The second kinds of pollutants contributed most to the WOI and have become the major pollutants in Caohai Lake. The score of the third kind of index varied between 3 and 32, which showed a good water quality status. The nutrients were the major factor influencing the fluctuation of water quality. Total nitrogen and total phosphorus are the specific pollutants of Caohai Lake.