Source Analysis of Heavy Metals in Surface Sediments of Lake Taihu

Abstract

根据太湖MS岩芯重金属元素与Al的线性回归分析及元素/Al、V/Al比率散点图变化规律,讨论了太湖沉积物中重金属元素的来源特征。结果表明:20世纪20年代中期以前,重金属元素主要为自然来源;20年代中期—70年代中期,尽管沉积物中Al、Fe、Zn、Mn、V、Cr等重金属元素含量随沉积物粒度变粗而明显下降,但除Hg受到一定程度的人为污染之外,其它重金属元素仍以自然来源为主,物源有所变化;70年代末期以来,沉积物中重金属元素人为污染逐渐加重,Pb、Cu、Zn、Hg、As等元素既有流域母质来源,又受到一定程度的人为污染。;Heavy metals of natural and anthropogenic sources are mixed in lake sediments, and it is difficult to discern.Based on linear regression analysis results and element chemical properties, A1 and V are selected as the concentration normalizing elements.The natural and anthropogenic sources contributing to the elemental concentrations in core MS of Lake Taihu are analyzed in terms of element-to-Al ratio versus V-to-Al ratio.Results show that heavy metals were from natural sources before mid 1920s.The heavy metals, such as Al,Fe,Mn,V, Cr, Pb, Cu, Zn and As, were from changed natural sources, and Hg originated from human pollution partly between mid 1920s and 1970s.The heavy metals, such as Pb, Cu, Zn, Hg, As, are contaminated by human pollution since mid 1970s.The source characters of heavy metals are correspondent with the human activities and economic development in Lake Taihu drainage basin.