江苏省沿海脊尾白虾养殖池塘重金属污染及潜在生态危害评价

An Assessment of Pollution and Potential Ecological Hazards of Heavy Metal in Aquaculture Ponds of Exopalaemon Carinicauda Holthuis on Jiangsu Coast

于2020年对江苏省沿海脊尾白虾养殖区池塘的海水、沉积物和脊尾白虾肌肉组织中的重金属进行分析,同时采用单因子污染指数法和潜在生态风险指数法对其沉积物重金属进行评价。结果显示,养殖池塘水体中铜(Cu)、铅(Pb)、镉(Cd)和锌(Zn)的平均质量浓度分别为3.13,1.02,0.094和28.02μg/L;沉积物中的平均质量分数分别为22.88,19.93,0.18和140.69 mg/kg;虾肌肉组织中的平均质量分数分别为12.49,0.50,0.18和28.65 mg/kg。生态环境质量评价结果表明,参照《海水水质标准》(GB 3097—1997),水体中Cu、Pb和Cd的质量浓度达到一类标准,Zn的质量浓度达到二类标准,属于清洁水平;沉积物中重金属的质量分数均达到《海洋沉积物质量标准》(GB 18668—2002)一类标准,属于较清洁水平,潜在生态风险为Cd>Zn>Cu>Pb,整体为轻微生态风险等级,Cd为主要污染元素;虾肌肉组织中重金属Pb和Cd的质量分数均达到《无公害食品海水虾》(NY 5058—2006)标准。

In this research,concentrations of four heavy metals in the environment and shrimp muscle tissue of aquaculture ponds of Exopalaemon carinicauda in Jiangsu coast had been surveyed.Two different methods,including single factor index(SFI)and Hakanson’s potential ecological risk index(PERI),were employed to assess the pollution of heavy metals,their main sources and spatial patterns of potential ecological risk.The survey results showed that the average concentrations of copper,lead,cadmium and zinc were 3.13,1.02,0.094 and 28.02μg/L in seawater,the corresponding results of heavy metals mentioned above were 22.88,19.93,0.18,140.69 mg/kg in the sediments,and 12.49,0.50,0.18,28.65 mg/kg in shrimps muscle tissue,respectively.The results of eco-environmental quality evaluation showed that the average concentrations of Cu and Cd in the aquatic seawater were below the first class of“Sea water quality standard(GB 3097—1997)”,while the average concentrations of Pb and Zn were below the second class.The concentrations of four metals in the sediments of the ponds were all less than the values of the first class of“Standard for marine sediments quality(GB 18668—2002)”.Overall,the potential ecological risk of four heavy metals discended from Cd to Pb,in the order of Cd>Zn>Cu>Pb.They were all ranged to the light ecological risk grade.The key pollution element was Cd in the four heavy metals above mentioned.The concentration of Pb and Cd in shrimp muscle tissue met the requirements set by“Pollution-free food-Sea water shrimp(NY 5058—2006)”.