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环境工程学报 2012
Effect of lime and superphosphate on maize production and heavy metals uptake by low-accumulating maize
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Abstract:
A field experiment was carried out to study effects of the combined application of lime and superphosphate on growth and heavy metals(Cd,Pb,Zn,Cu) concentration of a low-accumulating cultivar of Zea mays in a soil contaminated by wastewater from a lead/zinc mining.Changes in soil pH and available heavy metal contents after application of lime and superphosphate were also assessed.Results showed that the combined application of lime and superphosphate significantly increased the yields of Z.mays compared to the single additions.The favorable influence still exhibited in the second crop without further applications.The concentrations of Cd,Zn and Cu in grain of Z.mays were decreased by the single application of lime and the mixed application of lime and superphosphate.Furthermore,the best results was found in the treatments of the lime in the middle level(0.4 kg/m2) and the combined application of lime in high level(0.6 kg/m2) and the superphosphate in middle level(0.2 kg/m2).They were both below the limits of Chinese food standards.While the concentration of Pb in grain of Z.mays increased with lime addition,and exceeded the limit of Chinese food standard,and the combined application with superphasphate could not significantly decrease Pb content in corn grain.However they were still conformed to the Chinese feed standard.The concentrations of Cd,Pb,Zn and Cu in stem and leaf of Z.mays were all decreased by the single lime application and the lime and superphosphate mixed application and it was safe to be served as organic fertilizer.