Accumulation of Heavy Metals by ElevenTree Species in Xianshan Lake Wetland

Field sampling of leaf, stem, root and rhizospheric soilwas implemented on 11 tree species in April, 2016 in Xianshan Lake wetlandin Changxing, Zhejiang province. Determination was carried out on content of Cu, Cd, Zn, Pb and Hg. The results showed that the soil was healthy, though the concentration of Zn, Cd, Pb and Hg wasslightly higher than the national standard for grade one. The content of Cu was the highest in root of Ligustrum lucidum, stem of Salix matsudanas and leaf ofSapium sebiferum, respectively 49.267, 25.302 and 26.308 mg?kg-1. The content of Zn was the highest in root of S. sebiferum, stem and leaf of S. matsudana, respectively 212.105, 262.030 and 89.804 mg?kg-1. The content of Cd was the highest in root of S. triandra var. nipponica roots, stem and leaf ofS. matsudana, respectively 1.613, 1.443 and 0.723 mg?kg-1. The content ofHg was the highest in both root and stem of Cinnamomum camphora and leafof Phyllostachys heteroclada, respectively 0.070, 0.045 and 0.025mg?kg-1. The content ofPb was the highest in both root and leafof S. triandra var. nipponica (in summer) and stem of L. sinense, respectively 12.113, 11.050 and 5.930 mg?kg-1. Bio-concentration factor of Cu, Cd, Zn, Pb and Hg in tested plans ranged from 0.06-22.50, and translocation factor from 0.10-3.57. The determination found that the content of heavy metals in different plant organs in different tree species was orderedby Zn>Cu>Pb>Cd >Hg, and that in rhizosphere soil showed similar curve.