独山港表层沉积物重金属潜在生态风险的Monte Carlo模拟

Monte Carlo simulation on potential ecological risk evaluation of heavy metals in surface sediments from adjacent waters of Dushan Port,Jiaxing

基于沉积物重金属污染风险评估系统的不确定性和随机性,采用Monte Carlo模拟技术定量刻画沉积物重金属含量数据分布特征,并通过与潜在生态风险指数法的综合集成,评估了独山港海域表层沉积物重金属(Cu、Pb、Zn、Cr、Cd、Hg和As)的潜在生态风险水平。结果表明,港区中Cu、Pb和Zn为中等污染,Cd、Cr、Hg和As为轻微污染;综合污染指数C_d处于轻微污染的概率为38.32%,处于中等污染的概率为61.68%。所有7种重金属污染程度以及潜在生态风险指数RI均为轻微级。敏感性分析表明,Cu、Zn和Cr对C_d和RI起主导作用。

The uncertainties and randomness are the most general issues existing in the risk assessment of heavy metals in sediments,the Monte Carlo technique was introduced for simulating the Hakanson potential ecological risk index,in order to make the risk assessment more scientific and rational.Potential ecological risk assessment modified with the Monte Carlo technique was used to analyze the ecological risk of heavy metals（Cu、Pb、Zn、Cr、Cd、Hg、As）in surface sediments from adjacent waters of Dushan Port.The results show that the pollution degrees of Cu,Pb and Zn are medium contaminated,while others belongs to slight contaminated.The results also illuminate that the probabilities for slight degree and medium degree pollution levels of C_d（the comprehensive pollution index）are 38.32% and 61.68% respectively.As for the ecological risk,all of 7heavy metals and RI（the potential ecological risk index）are at a slight risk 1evel.The sensitive analyses indicate that Cu、Zn and Cr play leading roles in C_dand RI.