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Effects of different modes of vegetation restoration on soil heavy metal contents and soil enzyme activities:
A case study in damaged mountain body in Sibaoshan County, Zibo City, Shandong Province |
Zhang Liudong1,2, Li Chuanrong1,2, Liu Yun2, Lü Mengmeng2, Bing Beibei2, Han Congcong2 |
1. Taishan Forest Ecosystem Research Station;2. Key Laboratory of Agricultural Ecology and Environment, Shandong Agricultural University: 271018, Tai’an, Shandong, China |
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Abstract Exploitation of mineral resources has caused serious heavy metal pollution, in order to choose a reasonable vegetation restoration mode for the soil heavy metal pollution, were taken different vegetation restoration modes of the damaged mountain body in Sibaoshan County, Zibo City as object of the study, the activity of soil enzymes (polyphenol oxidase, catalase, peroxidase and urease), the content of heavy metals (Cu, Zn, Cd, Mn, Pb, Cr and Ni) together with its chemical properties (organic materials, the total nitrogen content, alkalinized nitrogen, available phosphorus and potassium and the pH value) were measured, and the content of heavy metals and the activity of enzymes in the soil of different vegetation restoration modes were analyzed. The results showed that soil was heavily polluted by Cu and Cd, lightly polluted by Zn, and not polluted by Mn, Pb, Cr and Ni. The contents of soil heavy metals for all vegetation restoration modes were lower than that of brushwood. Moreover, the remediation effect of Pinus thunbergii forest was best for soil polluted by Cu and Cd, whereas Platycladus orientalis forest performed best in remediation of soil polluted by Zn. Vertical distribution law of soil heavy metals was complex, an effective amount of of available Cu, Zn and Cd in lower layer is higher than in the upper layer by 24.00%-18.94%, 0.97%-20.09% and 5.48%-35.51%, respectively. In a variety of factors affecting soil enzyme activities, effect of content of heavy metals and soil chemical properties of soils was most obvious, and both were of equal importance, this study found that the soil enzyme activity was largely inhibited by Cu, Zn and of Cd, Hence, polyphenol oxidase, catalase and urease could be used as indicators for soil Cu pollution in damaged mountain body.
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Received: 29 August 2011
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