长江口滨岸重金属含量、形态及其分布特征  

Contents, Forms and Distributions of Heavy Metals in Surface Water and Sediments from Yangtze Estuary

作　　者：李亭亭[1] 王京刚[1] 王颖[2] 李丽芳[1] 尹世磊 

机构地区：[1]北京化工大学化学工程学院,北京100029 [2]北京师范大学环境学院水沙科学教育部重点实验室,北京100875

出　　处：《农业环境科学学报》2014年第6期1189-1196,共8页Journal of Agro-Environment Science

基　　金：国家重点基础研究计划(973)项目(2010CB429-003);国家自然科学基金(21177013);国家国际科技合作专项项目(2013DFR90290)

摘　　要：采集长江口南支、北支滨岸表层水体及沉积物样品,分析了其中7种重金属Cd、Cr、Cu、Hg、Ni、Pb、Zn和类金属As的含量以及表层沉积物中重金属的形态,并对其分布特征和生态风险进行分析。结果表明:表层水中7种重金属和类金属As含量均小于地表水I类标准;沉积物中As、Cr、Ni平均浓度大于效应临界浓度TEL值,具有潜在的生态风险;与2007年相比,沉积物中所有重金属平均含量均有所升高;由于沿岸排污、支流污染物输入,南支沉积物中多数重金属含量高于北支。重金属形态分析表明,Cd由于具有较高的离子交换态和碳酸盐结合态,生态风险较大。相关分析结果表明,除Hg和As外,沉积物中其他重金属之间均呈现较明显的正相关关系,多数重金属与活性铁铝氧化物、锰、TOC含量有明显的相关性。Contents, forms and distributions of heavy metals（Cd, Cr, Cu, Hg, Ni, Pb and Zn）and metalloid As in surface water and sedi-ments from the nearshore zones of the Yangtze Estuary were studied. Concentrations of all heavy metals and metalloid As in the surface wa-ter were lower than the Class I levels of GB 3838-2002 Surface Water Environment Quality Standards, whereas the mean concentrations of all metals in the sediments were higher in 2012 than in 2007. The concentrations of most metals in the sediments were higher from the south-ern than from the northern branch, due to more inputs of sewage and pollutants. The median concentrations of As, Cr and Ni in the sedi-ments were higher than the threshold effect levels（TEL）, implying potential ecological risks. Fractionations showed that As, Cr and Ni in the sediments were mainly present in the residual fraction. High Cd in the exchangeable and carbonate bound fractions indicated a higher eco-logical risk. There were obviously positive correlations between all metals with an exception of Hg and As. All metals had positive correla-tions with active iron and aluminum oxides and Mn except Zn, and with TOC except Hg.

关 键 词：长江口 沉积物 重金属 形态 生态风险 

分 类 号：X503[环境科学与工程—环境工程]