运用主成分分析法评价贵州草海水质污染

Application of Principal Component Analysis on Water Quality Assessment of Caohai Lake in Guizhou

近年来草海环境污染日趋严重,也引起人们的广泛关注。本文采用主成分分析法,对草海23个采样点的CODMn、BOD5、NH3-N、COD、TP、TN、DO共7个水质指标的实测数据进行了分析计算,提取前四个主成分对草海水体的污染程度进行定量化评价分级,评价草海主要污染物的污染程度。分析结果表明,草海的主要污染因子是CODMn、BOD5、TN、TP、COD,草海湖内水体污染程度具有上游污染较下游轻的明显的区域差异,水体污染主要受外源污染。草海水体的污染源主要是威宁县城居民生活污水和草海周边农业污染源,降低生活污染和科学使用农药及化肥是改善草海水质的重要途径。

The environmental pollution of Caohai Lake has become more serious recently, which has attracted ex- tensive attention. Using the principal component analysis, seven indexes of water quality including CODMn, BODs, NH3-N, COD, TP, TN and DO observed in twenty-three monitoring data of sampling point in Caohai Lake were an- alyzed. This paper made a quantitative estimate of the water contamination degree of Caohai Lake. Results showed that the main pollution factors of Caohai Lake were CODMn, BODs, TN, TP and COD. The pollution difference was obvious in the Caohai Lake with a fact that the upstream was less pollutant than the downstream. The pollution of Caohai Lake was exogenous. The major pollutants of Caohai Lake were life sewage from residents in Weining county and the agriculture pollution sources surrounding the lake. Therefore, reduction of the living pollution and scientific application of pesticides and chemical fertilizer are very important ways to improve the water quality of Caohai Lake.