大冶市城市湖泊表层水体中重金属的分布特征及其来源

Distribution of Heavy Metal Elements in Surface Water from Three Lakes in Daye City

以大冶市三个城市湖泊(三里七湖、尹家湖和红星湖)作为研究对象,测定了三个湖泊中22个采样点的pH值、电导率和表层水体中Mn、Ni、Zn、Cu和Cd 5种重金属元素的含量,并运用主成分分析法对表层水体中重金属的分布特征和来源进行了研究。结果表明:三个湖泊表层水体中5种重金属含量之间呈显著相关,可能具有相同的来源;湖泊表层水体中主要重金属的分布可由第一(F1)和第二(F2)两个主成分因子来反映,其贡献率分别为F1(Mn、Ni、Zn、Cd)83.315%、F2(Cu)8.989%,累积标准单位(CCU)与每种重金属含量、F1因子得分系数、电导率呈显著正相关,说明CCU是揭示湖泊重金属污染的有效指标;此外,重金属含量在各湖泊内部采样点间无显著性差异,而在三个湖泊之间则呈显著性差异,其中三里七湖处于重度污染状态。

This paper measures the mass concentration of heavy metal s（Mn, Ni, Zn,Cu and Cd） and the conductivity and pH in the surface water of three lakes （Sanliqi Lake,Yinjia Lake and Hongxing Lake ） in Daye City and analyzes the distribution characteristics and sources of heavy metals using the method of principal component analysis （PCA）. Results show there are significant correlations among the concentrations of heavy metals, which indicates that heavy metals may be derived from the same source~ the total variance is represented by the first principal factors F1 （Ca, Mn and Ni） of 83. 315~ and the second principal factors F2 （Zn, Cu and Cd） of 8. 989~, respeetively~ and there are sig- nificant correlations between cumulative criterion unit （CCU） and heavy metal concentrations, F1 scores and conductiv- ity, which indicates that CCU should be a useful index for detecting heavy metal pollution in these lakes. In addition, there are not significant differences of metal concentrations within lakes, while are significant differences of metal con- centrations among the three lakes~ and compared with other two lakes,Sanliqi Lake is in heavily polluted status.