上海城市公园土壤及灰尘中重金属污染特征

Characteristics of Heavy Metal Pollution in Soil and Dust of Urban Parks in Shanghai

对上海城市公园土壤和灰尘重金属含量水平进行了研究,并分析了土壤和灰尘中重金属的空间分布特征,结果表明,公园土壤中Pb、Zn、Cu、Cr、Cd和Ni的平均含量分别为55.06、198.54、44.57、77.01、0.40和31.17 mg.kg-1;公园灰尘中重金属含量普遍高于土壤,各元素的平均含量分别为416.63、906.29、235.89、162.59、1.58和92.19 mg.kg-1;同上海市土壤环境背景值相比,公园土壤(Ni除外)和灰尘中重金属元素含量均不同程度超出背景值;内外环线之间公园土壤(Zn除外)和灰尘重金属的平均含量均大于内环线以内公园;在不同的功能区,公园土壤和灰尘重金属的空间分布则无明显的规律性.通过Pearson相关分析和主成分分析,认为人类活动造成了公园土壤和灰尘中重金属的积累,其中最主要的污染源为工业和交通污染.

The contents of heavy metals in soils and dust of urban parks in Shanghai were studied, and the spatial distribution of heavy metals was also analyzed. The results showed that the average contents of Pb（55.06 mg·kg^-1 ）, Zn（198.54 m·kg^-1 ）, Cu（44.57 mg·kg^-1 ）, Cr （77.01 mg·kg^-1 ）, Cd（0.40 mg·kg^-1 ） and Ni（31.17 mg·kg^-1 ） in soils were lower than them in the dust, which were 416.63 mg·kg^-1 , 906.29 mg· kg^-1, 235.89 mg· kg^-1 , 162.59 mg· kg^-1, 1.58 mg· kg^-1 and 92.19 mg· kg^-1 respectively. The heavy metals in soils except Ni and all the six heavy metals in dust were higher than the background values in Shanghai more or less. The heavy metals average contents in dust in the parks of city central area were lower than them in the parks of city surrounding area, and the heavy metals in soils have similar spatial distribution patterns except for Zn. However, in different districts, the distribution of heavy metals in the soils and dust were not regular. Pearson correlative analysis and principal component analysis indicated that the heavy meals accumulation of the soils and dust were induced by anthropogenic input, furthermore traffic and industry were the main pollution sources.