椒江口表层沉积物中重金属及多氯联苯研究

Research of Heavy Metals and Polychlorinated Biphenyls in the Surface Sediments of Jiaojiang Estuary

于2013年对椒江口表层沉积物中重金属(Cu、Pb、Cd、Zn、Cr、Hg、As)和多氯联苯(PCBs)含量进行了测定,采用单因子污染指数法和Hakanson生态风险指数法评价沉积物污染状况及其潜在生态风险。结果表明,Cu、Pb、Cd、Zn、Cr、Hg、As和PCBs的平均含量分别为37.6、27.8、0.129、108.0、68.3、0.077、7.47 mg/kg和1.02μg/kg,其含量分布受到沉积物粒径的影响,沉积物中的细颗粒对重金属、PCBs污染物等具有更强的吸附、结合能力。评价结果显示:研究区域处于中等污染水平和中等潜在生态风险水平,各要素污染程度为Hg>Cu>Zn>Cd>Pb>Cr>As>PCBs,潜在生态风险程度排序为Hg>Cd>Cu>As>Pb>PCBs>Cr>Zn,Hg、Cd为首要潜在生态风险因子。

The contents of heavy metals(Cu, Pb, Cd, Zn, Cr, Hg, As) and polychlorinated biphenyls(PCBs) in the surface sediments of Jiaojiang estuary were analyzed in 2013. The pollution status and potential ecological risk were evaluated with single factor index and Hakanson ecological risk index. The results showed that the average concentrations of Cu, Pb, Cd, Zn,Cr, Hg, As and PCBs were as follows: 37.6, 27.8, 0.129, 108.0, 68.3, 0.077, 7.47 mg/kg and 1.02 μg/kg. Sediment grain size affected the distribution of the pollutants. The fine grained sediments have stronger adsorption and binding ability for heavy metals and PCBs. The pollution status belonged to moderate pollution degree mainly, with the order of Hg >Cu>Zn>Cd>Pb>Cr>As>PCBs. The potential ecological risk degree belonged to moderate level on the whole with the order of Hg >Cd >Cu >As>Pb>PCBs>Cr>Zn. The main pollution factors were Hg and Cd.