Levels of Cu, Ni, Zn, Pb and Cr were measured in soils and trees in ur ban Guangzhou, China. Tree and soil samples were collected from the roadside, ur ban parks and a university campus. Mean concentrations of Cu, Ni, Zn, Pb and Cr in tree leaves were 28.3, 7.7, 142.1, 23.4, and 195.1 mg/kg respectively. In a c omparison of heavy metal concentrations in tree leaves between roads and park lo cations, only Pb concentrations were significantly higher in the former. Heavy m etal concentrations were lower in the roots compared to leaves. It indicated tha t heavy metal pollution of trees is mainly from air pollution. For all top soil samples the mean concentrations of Cu, Ni, Zn, Pb and Cr were 24.3, 17.3, 121.5, 63.9 and 88.7 mg/kg, respectively. Heavy metal concentrations in roadside soils were higher and their coefficient of variation was higher than those in urban p arks. Comparing heavy metal concentrations in trees and soil between urban Guang zhou and Hainan Island, China, Cu, Ni, Zn, Pb and Cr levels in soils and plants in urban Guangzhou were evidently affected by the human impact. However the heav y metal content in the soil compared to some international standards do not give cause for concern. Some observations on the implications of the data for enviro nmental monitoring are made.
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