南四湖表层底泥重金属空间分布及污染程度评价

测试南四湖湖区29个表层底泥中重金属Hg、Cd、Cr、Pb、Ni、Cu、Zn和类金属As的质量比,得到南四湖湖区重金属污染的空间分布特征。结合地质积累指数法和潜在生态风险指数法,对南四湖重金属污染程度进行评价。结果表明,南四湖已受到重金属元素的污染,属于中等程度污染湖泊,其中以As、Hg、Cd、Pb元素污染严重。除了As、Cd元素在下级湖表层底泥中的质量比略高外,其他重金属元素在上级湖的污染程度普遍比在下级湖的高;二级坝以北的昭阳湖湖区潜在生态危害最为严重,其次是南阳湖、微山湖、独山湖和二级坝以南的昭阳湖湖区。

Spatial distribution and pollution assessment of heavy metals in surface sediments of Nansihu Lake

The contents of heavy metals, including Hg, Cd, Cr, Pb, Ni, Cu, and Zn, and As, which is a metalloid, in 29 samples of surface sediments in Nansihu Lake were investigated. The spatial distribution characteristics of the heavy metals were obtained. The index of geo-accumulation and potential ecological risk index methods were used to assess the heavy metal pollution in Nansihu Lake. The results show that the lake has been moderately polluted by heavy metals. As, Hg, Cd, and Pb have caused serious pollution in the lake. The heavy metal pollution in the lakes to the north of a grade-Ⅱ dam was more serious than to the south, except for As and Cd, which caused more serious pollution in the lakes to the south of the dam than to the north. Zhaoyang Lake to the north of the dam had the highest potential ecological risk index, followed by Nanyang Lake, Weishan Lake, Dushan Lake, and Zhaoyang Lake to the south of the dam.