采用电感耦合等离子体质谱法(ICP-MS)对太湖22个采样点过滤水和18个采样点表层沉积物中镉(Cd)、 铬(Cr)、 铜(Cu)、 镍(Ni)、 铅(Pb)和锌(Zn)六种重金属元素含量进行测定。 同时, 采用单因子指数法(Ii)、 内梅罗综合指数法(I)、 地质累积指数法(Igeo)、 潜在生态风险指数法(RI)和平均可能影响浓度商法(mPEC-Q)分别对过滤水和表层沉积物进行了污染评价。 结果表明, 除S3, S4, S20, S22采样点外过滤水中Cu, Ni和Zn元素含量最高。 其重金属平均含量水平大小排序为: Zn>Ni>Cu>Cr>Cd>Pb。 研究区域的Ii和I值均小于1, 表明所有采样点五种重金属元素(Ni无标准限值)均处于清洁状态。 而在表层沉积物中六种元素含量均超过当地背景值, 其平均含量大小排序为: Zn>Cr>Pb>Ni>Cu>Cd, 其中S12采样点(渔民生态园)六种元素含量最高, 且它们具有最大的Igeo, RI(327)和mPEC-Q(0.605), 表明沉积物存在不同程度的污染。 源分析的结果表明, 六种重金属具有较大的相关性, 且Cd, Cu, Pb和Zn受电镀、 冶炼工业生产及农业活动中化肥使用的影响较大。 研究结果对追溯太湖重金属来源、 迁移规律、 生物效应和综合治理提供可信的实验依据。

Cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), zinc (Zn) and lead (Pb) of filtered water in 22 sampling sites and surface sediments of 18 sampling sites in Taihu Lake were measured with inductively coupled plasma mass spectrometry (ICP-MS). Meanwhile, in filtered water and surface sediments, the pollution evaluation were conducted by using singer factor pollution (Ii), intergrated Nemerow pollution index (I), index of geoaccumulation (Igeo), potential ecological risk index (RI) and mean potential effects concentration quotient (mPEC-Q), respectively. The results showed that the contents of Cu, Ni and Zn were the highest in filtered water except S3, S4, S20 and S22 sampling sites. The sequence of heavy metals content levels: Zn>Ni>Cu>Cr>Cd>Pb. The Ii and I values in the study area were less than 1, indicating that five heavy metals (Ni has no standard limit) were in clean condition in all sampling points. The contents of the six elements in the surface sediments exceeded the local background values, and the sequence of average contents: Zn>Cr>Pb>Ni>Cu>Cd, and at S12 sampling point (Fisherman’s Ecological Park), the content of the six elements were the highest. They had the largest Igeo, RI (327) and mPEC-Q (0.605), indicating that there were different degrees of pollution in sediments. The results of source analysis showed that the six heavy metals had a large correlation, Cd, Cu, Pb, Zn were greatly influenced by electroplating, smelting industrial production and the use of chemical fertilizers at agricultural activities. The results will provide a credible experimental basis for tracing the origin, migration, biological effects and comprehensive management of heavy metals in Taihu Lake.