摘要
为了探讨多重环境因素变化下黄河口沉积物中重金属的环境地球化学行为,研究了2011年7～8月黄河口14个表层沉积物样品中Cu、Pb、Zn、Cr、As和Hg等6种重金属的分布特征、环境影响因素及其生态风险.结果表明,黄河口表层沉积物中6种重金属平均含量分别为Cu:(16.5±2.7)mg.kg-1,Pb:(16.0±3.4)mg.kg-1,Zn:(21.0±3.3)mg.kg-1,Cr:(17.4±3.1)mg.kg-1,As:(6.5±1.2)mg.kg-1,Hg:(0.044 4±0.030 7)mg.kg-1.与我国近海其它区域比较,研究区域重金属含量均处于较低水平.表层沉积物中河口南侧沉积物中重金属含量比北侧高,并随河口向外沉积物中重金属含量逐渐降低,此分布趋势在莱州湾西南部尤为明显.重金属间无显著相关关系,重金属含量与细颗粒物、总有机碳(total organic carbon,TOC)之间亦无显著相关关系,表明黄河口表层沉积物中重金属受到汛期黄河上游复杂来源的影响,且粒度、TOC皆非主控因素;TOC与黏土的相关系数达0.724(P<0.05),显示TOC更易富集于黏土中.与多种背景值及一致性沉积物质量基准比较,黄河口部分站位Pb含量超出背景值,但该含量水平引发有害生物效应的可能性不大,尽管重金属含量偏低,生态风险较小,但近年来Hg、Pb的风险有升高的趋势.
The contents of Cu,Pb,Zn,Cr,As and Hg in surface sediment from 14 sampling sites in the Huanghe estuary during July-August,2011 were measured to investigate environmental geochemical characteristics of heavy metals related to multiple factors.The distribution,relationship with fine fraction and TOC,and sediment quality assessment concerning heavy metals were analyzed.The results showed that average concentrations of Cu,Pb,Zn,Cr,As and Hg in the Huanghe estuary were（16.5±2.7）,（16.0±3.4）,（21.0±3.3）,（17.4±3.1）,（6.5±1.2）,（0.044 4±0.030 7）mg·kg-1,respectively,which were lower than those in other typical areas along the coast of China.The distribution of metals displayed higher profiles in south than that in north of the Huanghe estuary,with a trend of increase seaward,especially for stations in southwest of the Laizhou bay.The insignificant correlation among metals indicated the complex sources of heavy metals in flood season.Pearson correlation was also conducted between metal contents and percentage of fine particulates and TOC,which was also insignificant,suggesting heavy metal concentration and distribution in the study region were also controlled by other factors except grain size and TOC.There was a good correlation between clay fraction and TOC（r=0.724,P0.05）,indicating TOC tends to accumulate in clay.Compared with variety of background values and an internationally used consensus-based sediment quality guidelines（CBSQGs） for saltwater ecosystem,heavy metals in surface sediments from the Huanghe estuary implied a low probability of toxic effect,despite a sharp contamination trend pertaining to Hg and Pb since 1980s.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2013年第4期1324-1332,共9页
Environmental Science
基金
国家海洋局环境评价项目(DOMEP(MEA)-01-01)
国家自然科学基金创新研究群体项目(41121064)
关键词
重金属
背景值
沉积物质量基准
黄河汛期
黄河口
表层沉积物
heavy metal
background value
sediment quality guidelines（SQGs）
flooding season
the Huanghe estuary
surface sediment
