广西主要贝类养殖区重金属含量分布特征及污染评价

Distribution characteristics and pollution evaluation of heavy metals from major shellfish culture areas of Guangxi

关键词:  贝类养殖区  分布特征  重金属  地积累指数  富集系数  污染评价

Key words:  shellfish culture areas  distribution characteristics  heavy metal  index of geo-accumulation  enrichment coefficient  pollution assessment

摘要:

为探究广西主要贝类养殖区重金属含量的分布状况及污染水平，依据2016-2018年广西主要贝类养殖区的海水、表层沉积物及生物体中重金属元素（Cu、Pb、Zn、Cd、Hg、As）的调查分析数据，分别采用单因子指数法、地积累指数法和生物富集系数对养殖区重金属进行了污染评价。结果表明：海水中各重金属的含量分布为Zn＞Cu＞As＞Pb＞Cd＞Hg，污染程度为Cu＞Hg＞Zn＝Pb＞Cd＞As；沉积物中各重金属的含量分布为Zn＞Cu＞Pb＞As＞Cd＞Hg，污染程度为As＞Cd＞Pb＞Hg＞Cu＝Zn；近江牡蛎贝体中各重金属的含量分布为Zn＞Cu＞Cd＞As＞Pb＞Hg，污染程度为Zn＞Cu＞Cd＞Pb＞Hg＞As，生物富集能力为Zn＞Cu＞Cd＞Hg＞As＞Pb。可知，广西主要贝类养殖区的海水水质较好，属于本底水平；沉积物环境属于较清洁水平，适合贝类养殖；生物体中重金属存在不同程度的污染，其中Zn、Cu和Cd的富集积累现象较显著，应引起重视。

Abstract:

In order to explore the distribution and pollution level of heavy metal content in major shellfish culture areas of Guangxi,based on the investigation and analysis data of heavy metal elements (Cu,Pb,Zn,Cd,Hg,As) in seawater,surface sediments and organisms of major shellfish culture areas of Guangxi during 2016-2018,single factor index method,geo-accumulation index method and biological enrichment coefficient were used to evaluate the pollution of heavy metals in culture areas.The results show that the content distribution of all heavy metals in seawater is Zn>Cu>As>Pb>Cd>Hg,and the pollution degree is Cu>Hg>Zn=Pb>Cd>As.The content distribution of heavy metals in sediments is Zn>Cu>Pb>As>Cd>Hg,and the pollution degree is As>Cd>Pb>Hg>Cu=Zn.The content distribution of heavy metals in oyster oysters is Zn>Cu>Cd>As>Pb>Hg,the pollution degree is Zn>Cu>Cd>Pb>Hg>As,and the biological enrichment capacity is Zn>Cu>Cd>Hg>As>Pb.It can be seen that the seawater quality of the main shellfish aquaculture areas in Guangxi is good,which belongs to the background level.The sediment environment belongs to relatively clean level,suitable for shellfish culture;Heavy metals in organisms are polluted in different degrees,and the accumulation of Zn,Cu and Cd is obvious, which should be paid more attention to.