天山地表水重金属的赋存特征和来源分析

2011年8月1日~15日,在天山山地以约50km的间距取51个水样品,并对代表性Pb、Ni、Cd、Co、Hg、As、Cu、Mn、Zn、Cr 10种重金属元素进行测试.然后运用相关分析、主成分分析和聚类分析等方法对这些重金属的赋存特征与来源做了探讨,结果表明:10种重金属变化范围为0~91.876μg/L.在所有水样中10种重金属元素平均浓度顺序为:Ni>As>Cu>Zn>Co>Mn>Hg>Cd>Pb;不同类型样品中重金属赋存特征为:灌溉渠道>河流支流>河流干流>湖泊>机井.相关分析结果显示,Cu、Mn、Hg、Zn、Ni和其他元素相关性较强.主成分分析表明,样品中重金属指标第1主成分Cu、Ni、Cr、Cd、As、Co和Cr来源于河流底部母岩矿物的风化及沿岸陆源碎屑矿物的自然风化侵蚀作用,第2主成分Mn、Hg、Zn、Pb来源于城镇附近的污染工厂及道路附近含铅污染物,第3主成分Hg、Pb、Cr主要来源于工农业排污.聚类分析表明:样品中重金元属可归为4类,其中Co、Ni、Cr为一类,Cd、Cu、As为一类,Pb、Zn、Mn为一类,Hg单独为一类.单一来源如,锌、铜矿开采、河流底母岩重金属迁移等因素对样品中重金属浓度影响较大.

Contents and sources of heavy metals in surface water in the Tianshan Mountain

During August 1~15, 2011, 51 surface water samples were collected from the northern slope of Tianshan Mountains. Contents of ten heavy metals, i.e., Pb, Ni, Cd, Co, Hg, As, Cu, Mn, Zn and Cr were tested in the laboratory by using ICP-MS. The statistical methods, such as correlation analysis, principal component analysis and cluster analysis were then employed to identify the sources of these heavy metals. contents of 10 heavy metals ranged from 0 to 91.876 μg/L. The order of heavy metals in the same samples was: Ni>As>Cu>Zn>Co>Mn>Hg>Cd>Pb. The correlation analysis shows a closer correlation between Cu, Mn, Hg, Zn, Ni and other elements. The principal component analysis shows that heavy metals in the samples can be divided into the first principal component of Cu, Ni, Cr, Cd, As, Co and Cr, which comes from the natural weathering erosion of the bed parent rock and granular minerals at the bottom and bank of the river and stream; the second principal component includes Mn, Hg, Zn, Pb, indicating a source from factories and traffics; and the third principal component of Hg, Pb and Cr, which comes from industrial and agriculture pollution. These heavy metals can be classified into four clusters, i.e., cluster one (Co, Ni, Cr), cluster two (Cd, Cu), cluster three (Pb, Zn, Mn) and cluster four (Hg).