张家港河金港段表层沉积物中氮磷及重金属污染评价

Pollution assessment of nitrogen,phosphorus and heavy metals in surface sediments of Zhangjiagang River Jingang section

为了解张家港河金港段表层沉积物中氮磷及重金属的污染特征,对张家港河金港段表层沉积物展开了调查,基于单项污染指数法、综合污染指数法对总氮、总磷进行评价,基于地累积指数法、污染负荷指数法对重金属做了评价。结果表明:张家港河金港段表层沉积物中TN整体为轻度污染状态,TP除个别点位外,大部分处于重度污染状态。张家港河金港段表层沉积物中w(Cu)、w(Zn)、w(Cr)、w(Ni)、w(Pb)、w(As)、w(Hg)、w(Cd)的平均值分别是江苏省土壤重金属环境背景值的4.923、4.053、1.653、1.760、1.454、1.313、1.900、6.178倍,Cu、Zn、Cd多为中度及偏中度污染,Cr、Ni、Pb、As、Hg多为清洁及轻度污染。区域底泥重金属污染程度为I级中等污染,南部污染最重。

In order to understand the pollution characteristics of nitrogen,phosphorus and heavy metals in surface sediments of Zhangjiagang River jinggang section,the surface sediments of Zhangjiagang River jinggang section were investigated.Based on the single pollution index method and the comprehensive pollution index method,the total nitrogen and total phosphorus were evaluated.Based on the cumulative index method and the pollution load index method,the heavy metals were evaluated.The results showed that the TN was mildly polluted,the TP were heavily polluted except for individual points.The average of Cu,Zn,Cr,Ni,Pb,As,Hg,Cd in the surface sediments were4.923,4.053,1.653,1.760,1.454,1.131,1.900and6.178times higher than the background values respectively.The Cu,Zn and Cd were mildly to moderately polluted and moderately polluted,Cr,Ni,Pb,As and Hg were mostly clean and mildly polluted.The degree of heavy metal pollution in the area was