基于主成分分析的河流沉积物重金属污染评价

Assessment Model of Heavy Metal Pollution for Sediments Based on Principal Component Analysis

采用环境评价领域内的污染负荷指数法、潜在生态危险指数法以及数学统计分析领域内的变异系数法和主成分分析法,对山东省境内的娄山河、墨水河、小清河、沂河等4条代表性河流的沉积物重金属污染水平、生态危害、污染来源及分布进行了评价和分析。对4条河流沉积物中的8种重金属（Cu、As、Pb、Hg、Zn、Cd、Cr、Ni）含量的分析结果表明,娄山河、墨水河沉积物重金属含量较高,综合污染情况较重,污染负荷指数范围达到了75.35-83.2,潜在生态危险指数为中级,小清河、沂河则较好,仅仅轻微污染;针对4条河流进行的污染来源相关性及主成分分析结果表明,其污染来源具有相似性,污染来源主要分为：工业＂三废＂、生活垃圾、农药化肥等生产生活活动。总的来说,该文在综合评价山东省流域内的河流污染状况过程中,运用了多种评价方法进行科学评估,为土壤重金属污染评价提供了一种较全面的方法。

To assess pollution status of heavy metals in sediments of 4 rivers in Shandong Province, four methods, including the potential ecological risk index and the pollution load index which in EA field, and also including the coefficient of variance and the principal component analysis in statistical analysis field were introduced to evaluate the pollution degree and the potential ecological risks of heavy metals. The result of assessment on 8 elements of heavy metal（Cu, As, Pb, Hg, Zn, Cd,Cr, Ni） in 4 rivers showed that the comprehensive pollution of heavy metals in urban（Loushan River and Moshui River）sediments was serious,with range of pollution load index varied in 75.35-83.2, and potential ecological risk all satisfactory to intermediate level. The pollution status of the suburban（Xiaoqing River and Yi River） belonged to slight pollution. The factor analysis suggested that the sources of all 8 heavy metals in 4 rivers from urban and suburban areas were similar, and came mainly from industrial sewage, waste and pesticide. This comprehensive assessment model which includes variety of evaluation methods could be used in the assessment of heavy metal pollution in urban and suburban rivers, which offered a new idea for assessment of soil heavy metal pollution.