广东阳江近岸海域表层海水重金属含量及潜在生态风险分析

Analysis of heavy metal content and potential ecological risk in surface seawater of Yangjiang offshore area of Guangdong province

为了解广东阳江近岸海域表层海水重金属含量及潜在生态风险,采集了14个站位的表层海水样,分析讨论了该海域表层海水中7种重金属Cr、Cu、Zn、Cd、Pb、As、Hg的含量分布特征,采用Hakanson潜在生态危害指数法评价其生态风险。结果表明:广东阳江近岸海域表层海水重金属Cr、Cu、Zn、Cd、Pb、As、Hg的平均浓度分别为1.10、5.25、9.91、0.027、0.945、1.06、0.027μg/L。其中Cr、Zn、Cd、Pb、As、Hg六种元素符合一类海水水质标准,Cu符合二类海水水质标准;7种重金属间相关性较强,各重金属与不同环境参数也存在一定的相关性。对潜在生态风险指数进行分析,计算出RI平均值为6.59,属于轻微生态危害,总体为清洁水平。

To understand Yangjiang,Guangdong nearshore sea surface water content and potential ecological risk of heavy metals,samples surface waters were collected at 14 stations.The content distribution characteristics of 7 kinds of heavy metals were analyzed in surface waters including Cr,Cu,Zn,Cd,Pb,As,and Hg.The Hakanson method was adopted to evaluate their ecological risk index and potential ecological harm.The results showed that the average concentrations of heavy metals Cr,Cu,Zn,Cd,Pb,As and Hg in the surface waters off Yangjiang were 1.10μg/L,5.25μg/L,9.91μg/L,0.027μg/L,0.945μg/L,1.06μg/L and 0.027μg/L,respectively.Among them,Cr,Zn,Cd,Pb,As and Hg met the quality standards for class I seawater,while Cu met the quality standards for class II seawater.There was a strong correlation among the 7 heavy metals,and each heavy metal also had a certain correlation with different environmental parameters.Based on the analysis of the potential ecological risk index,the average value of RI was calculated to be 6.59,which was a slight ecological hazard and the overall level of cleanliness.