上海市小城镇河流沉积物重金属污染特征研究

Pollution Character of Heavy Metals in River Sediments from Small Towns,Shanghai

以3个典型小城镇河流为例，研究上海市小城镇河流沉积物重金属污染特征．结果显示，沉积物Zn的浓度在3．11～3．74g／kg之间，是农用污泥Zn使用允许最高值0．5g／kg的6～8倍，沉积物Zn的极度污染已经成为上海市小城镇河流沉积物区域性环境问题；沉积物Pb和Cu的浓度分别在0．03～1．00g／kg和0．07～0．20g／kg之间，小城镇河流沉积物也明显受到Pb和Cu污染且污染区域差异性大，沉积物中铁、锰、铬等重金属污染相对较轻；毒性弱的Fe，Mn，Zn沉积物区域污染差异性相对小，而毒性强的Pb，Cu，Cr区域差异性相对较大；沉积物重金属污染一般中型河流污染相对稍突出，小城镇河流沉积物由于Zn的严重污染不能用作施用污泥；利用重金属与TP，重金属与Fe之间的相关性探源结果显示：小城镇生活污水的地表排放使得街道灰尘成为河流沉积物Pb的一个重要来源．

By selected three small towns, we studied the pollution character of heavy metals in sediments. Results show that the content of sediments-Zn is between 3.11 g/kg and 3.74g/kg, which is heavily excess the criterion of farming fertilized by sullage. The Zn-pollution of sediments has been a territorial and heavily pollution question of small towns, the content of sediments-Pb is between 0.03 g/kg and 1.00g/kg, And that of sediments-Cu is between 0.07g/kg and 0.20g/kg. The river sediments has also been polluted by Pb and Cu. To the diversity-region, light-toxicity metals（Fe, Mn, Zn） is less than heavy-toxicity metals（Pb, Cu, Cr）. The river sediments from small towns can not be fertilized to the farmlands. By analyzed the relativity of TP-metals（Fe, Cr, Cu, Mn, Pb, Zn） and that of Fe-metals（Fe, Cr, Cu, Mn, Pb, Zn）, we can conclude living sewage form small towns is a source of metals in sediments. Street-dust is an important source of sediments-Pb through surface-eroded by living-sewage.