材料期刊网

为了解东江淡水河流域重金属污染状况，测定地表水和沉积物中7种典型重金属锰、锌、铜、镍、铬、铅和汞（ Mn、Zn、Cu、Ni、Cr、Pb、Hg）的含量水平，并采用地累积指数法和潜在生态危害指数法，评价沉积物环境质量状况．结果表明，淡水河地表水中 Mn、Zn、Cu、Ni、Cr、Pb 和 Hg 的平均值浓度分别为305．00、151．50、67．50、56．50、28．50、15．00、0．07μg·L－1；淡水河流域地表水重金属含量处于较低水平，且大部分重金属枯水期浓度高于丰水期．沉积物中Mn、Zn、Cu、Ni、Cr、Pb和Hg的平均值浓度分别为714．00、993．50、289．50、188．50、301．50、118．50、0．43 mg·kg－1．表层沉积物中Cu和Hg是污染最为严重的金属，Mn和Cr的污染水平相对较低，除Cu枯水期浓度明显高于丰水期外，其它6种重金属丰水期和枯水期差异较小．淡水河地表水和沉积物重金属平均含量整体高于西枝江和东江，且上游污染程度较高．相关性分析和主成分分析结果表明Zn、Ni、Cr、Mn和Pb的污染来源于流域内盛行的电子电镀产业，Hg和Cu的污染来自于其它产业．潜在生态风险结果表明，淡水河中游具有极强的生态危害，西枝江具有轻微的生态危害，东江有强的生态危害，但数值处于强的生态危害范围的下限．淡水河上中游及其支流周边工业聚集区是重金属污染的最主要来源．

In order to comprehensively evaluate pollution level of Danshui River, the concentrations and distribution characteristics of seven heavy metals ( Mn, Zn, Cu, Ni, Cr, Pb and Hg ) were analyzed. Heavy metal pollution in the sediments from Danshui River and its tributaries was analyzed and evaluated using geo?accumulation index (Igeo) and potential ecological risk index (RI). The results indicated that the average concentrations of Mn,Zn,Cu,Ni,Cr,Pb and Hg in surface water were 305.00, 151. 50, 67. 50, 56. 50, 28. 50, 15. 00 and 0. 07 μg·L-1, respectively, and were relatively low. The concentrations in the dry season were in most cases higher than those in the wet season. Their average concentrations in the sediments were 714. 00, 993. 50, 289. 50, 188. 50, 301.50, 118.50 and 0.43 mg·kg-1 , respectively. Copper and mercury were the most polluted metals in the sediment, while manganese and chromium pollution levels were relatively low. Except Cu, other six metals in the sediment did not show much seasonal variation. But the concentration of copper in the dry season was higher than wet season. The average contents of heavy metals in surface water and sediments of Danshui River were higher than Xizhijiang and Dongjiang, with high pollution sites occurred in the upstream of Danshui River. The prevalent pollution source of Zn, Ni, Cr, Mn and Pb in the basin was electronic and electroplating industry, and pollution source of mercury and copper came from other industries. The results of potential ecological risk indicated that the middle reaches of Danshui River had extremely high ecological hazard, Xizhijiang had low ecological hazard, Dongjiang had high ecological hazard but the value was close to the lower limit. The industrial zone in upper ( middle) reaches and tributaries of Danshui River were the main source of pollution.