通过对上海市区44个公园土壤中Pb含量的调查,发现表层土壤中Pb的平均含量为55.06mg/kg,变幅为26.39~174.35mg/kg,为上海市土壤环境背景值的1.04~6.85倍。运用地积累指数法对公园表层土壤Pb污染进行评价,结果表明:超过半数的公园为轻度污染至中等污染,近1/3的公园无污染,6个公园达到中等污染和中等污染至强污染水平。通过对土壤Pb含量的空间分布分析发现,上海市区公园土壤中Pb主要来源于交通和工业污染,土壤Pb含量与公园建成时间无显著性相关。
Lead concentrations in surface soils of 44 urban parks of Shanghai were determined. Results showed that Pb concentrations in the soils averaged 55.06 mg/kg, ranging from 26.4 to 174.4 mg/kg, which was 1.04 - 6.85 times the background value of soil Pb in Shanghai. Geoaccumulation index was used to assess Pb pollution of the surface soils. Results indicated that more than a half of the parks were light- or medium-polluted, nearly one third of the parks were not polluted, and 6 parks were medium- and medium-heavily polluted. The spatial distribution of Pb concentrations showed Pb might come from traffic and industry, and Pb concentrations were not significantly correlated to the history or duration of the parks.