湛江港海水中铜、锌、铅、镉的周年变化与水质评价

Seasonal Change of Contents of Cu,Zn,Pb and Cd and Quality Assessment in Seawater of Zhanjiang Harbor

于2008年3月至2009年1月用电感耦合等离子体质谱法(ICP-MS)对湛江港海水中的铜(Cu)、锌(Zn)、铅(Pb)、镉(Cd)进行调查。分析结果表明:2008年湛江港湾海水中Cu、Zn、Pb、Cd含量较低,年平均含量分别为4.46×10-3mg/L、14.2×10-3mg/L、0.795×10-3mg/L、0.588×10-3mg/L,总体上表层海水中Cu、Zn、Pb、Cd的含量均略低于底层海水。各季度海水中重金属含量的比较结果为:Cu的含量秋季>春季>夏季>冬季,Zn的含量夏季>春季>秋季>冬季,Pb的含量秋季>夏季>春季>冬季,Cd的含量冬季>夏季>秋季>春季。湛江港湾的Cu、Zn、Pb、Cd的含量均在中部水域湛江港码头核心作业区最高,港湾外较低;Zn、Cd在港湾内的含量较高。按照单因子污染指数法评价,湛江港湾海水中的Cu、Zn、Pb、Cd含量均低于国家二类海水水质标准规定的限值,水质较好。

The survey and analysis on heavy metal（Cu,Zn,Pb,Cd） in seawater were carried out from March of 2008 to January of 2009 in Zhanjiang harbor.The results showed that the concentrations of Cu,Zn,Pb,Cd were low as a whole for a year round in 2008,with respectively average values of 0.00446mg/L,0.0142mg/L,0.000795mg/L,0.000588mg/L,and the concentrations of Cu,Zn,Pb,Cd in the bottom seawater showed a slight higher than that in the surface for most stations.As for seasonal change,the content of Cu followed a change rule of autumnspringsummerwinter,while Zn followed with a rule of summerspringautumnwinter,and Pb followed a rule of autumnsummerspringwinter,and Cd followed a rule of wintersummerspringautumn.The contents of Cu,Zn,Pb,Cd were the highest in the central area,besides the content of Zn,Cd in inner bay were rather high.Based on the assessment results with the single factor of pollution index,the water quality in Zhanjiang harbor was good.