长江口及邻近海域沉积物中重金属研究--时空分布及污染分析

Spatial and temporal distribution and pollution analysis of the heavy metals in surface sediments of the Changjiang Estuary and its adjacent areas

根据2005-2009年5月和8月对长江口及邻近海域的调查监测资料,研究了沉积物中6种重金属（Cu、Zn、Pb、Cd、Hg、As）的时空分布特征,探讨了其影响机理,并对其污染进行了分析.结果表明,6种重金属总体分布格局呈由近岸向远岸递减,并在泥质区普遍存在一个重金属含量的高值区;陆源输送、水动力条件、细颗粒物质的吸附以及絮凝作用是控制重金属分布的主要因素;陆源输送、大气干湿沉降、有机物释放、重金属存在形态之间的转换是重金属来源的重要途径;基于因子总得分的污染分析显示,沉积物中重金属污染分布呈由近岸向远岸递减的趋势.

Based on the data obtained from the Changjiang Estuary and its adjacent areas in May and August,year 2005 from 2009,the distribution characteristics of the heavy metals（Cu,Zn,Pb,Cd,As,Hg） in surface sediments and their influencing mechanisms were analyzed,and the pollution status was further analyzed.The results showed that the general distribution pattern of heavy metals was characterized by decrease from the alongshore to the open sea and enriched in mud areas.Terrigenous discharge,hydrographic dynamics,adsorption and flocculation played important roles in the distribution of heavy metals.Terrigenous discharge,atmospheric deposition（dry and wet）,emissions of organic matter,form transform were the major sources of heavy metals.Total factor notches showed that the distribution pattern of heavy metals contamination was characterized by decrease from the alongshore to the open sea.