关键词: 非点源污染, 预测, 模拟, 面积阈值, 城市建设用地

Abstract: Woody plants play an important role on phytoremediation of heavy metal contaminated soil during urban greening. In this study, the ability of 54 woody species on phytoextraction of Cu, Pb and Zn in soil were evaluated with pot experiment. The results showed that the contents of Cu (22.91-370.96 mg·kg^-1), Pb (0.21-27.00 mg·kg^-1) and Zn (25.03-539.02 mg·kg^-1) in roots of woody plants were significantly higher than the aboveground parts. Cu and Zn contents in aboveground parts of 11 and 15 woody species exceeded 30 and 150 mg·kg^-1 respectively, while only Robinia pseudoacacia had a Pb content more than 10 mg·kg^-1. There were 16 woody species with strong phytoextraction ability for Zn, but few species with phytoextraction ability for Cu and Pb. With comprehensive evaluation, Fraxinus chinensis, Callicarpa dichotoma, Lagerstroemia indica,Rhus chinensis, Sambucus williamsii,R. pseudoacacia, Liquidambar formosana, Broussonetia papyrifera,Idesia polycarpa and Viburnum odoratissimumhad strong ability of phytoextraction of heavy metals from soil. F. chinensisis an ideal tree species for phytoremediation of urban soil polluted by Cu, Pb and Zn.

Key words: simulation, non-point source pollution, urban building land, prediction, area threshold.