上海城市公园灰尘重金属污染及其潜在生态风险评价

通过对上海城市公园灰尘重金属含量的调查,发现上海城市公园灰尘重金属Pb、Zn、Cu、Cr、Cd和Ni含量的平均值分别为416.63 mg/kg、906.29 mg/kg2、35.89 mg/kg1、62.59 mg/kg1、.58 mg/kg和92.19 mg/kg,同上海市土壤环境背景值相比,均处于较高的积累水平。公园灰尘重金属空间上的分布特征表现为:内外环线之间公园灰尘各重金属元素含量平均值均高于内环线内公园;通过分析判定公园灰尘中较高的重金属含量可能主要源于交通和工业造成的污染。运用潜在生态危害指数法来评价上海城市公园灰尘重金属污染状况,发现单种重金属造成的潜在生态危害表现为:Cd>Pb>Cu>Ni>Zn>Cr;公园灰尘6种重金属潜在生态危害达到一个相当高的水平,在所调查的公园中,63.6%的公园灰尘重金属生态危害达到极高水平,29.5%的公园达到高水平,6.8%的公园处于较高水平。

Heavy Metal Pollution and the Ecological Risk in Dust of Shanghai Urban Parks

Heavy metal concentrations of dust taken from the parks in Shanghai urban area were studied.The results showed that the average concentrations of Pb, Zn,Cu,Cr,Cd and Ni were 416.63,906.29,235.89,162.59,1.58 and 92.19 mg/kg respectively.Compared with the backgrounds of soils in Shanghai,the heavy metal concentrations of the dust got higher values.The spatial distribution of heavy metals in the dust of urban parks was regular.The average concentrations of heavy metals in the inner ring parks were lower than the parks between outer ring and inner ring,which may due to the distribution of the industry.The higher concentrations of heavy metals in the dust may come from the pollutants produced by traffic and industry.The potential ecological risk of heavy metal pollution were assessed by Las Hakanson,and the results indicated that 63.6% of the researched parks from parks got to sky-high ecological hazards,29.5% got to high ecological hazards,and only 6.8% were upper level.Different heavy metals caused various ecological hazards,and the effect of the ecological hazards was Cd>Pb>Cu>Ni>Zn>Cr.