Balances of heavy metals in small-scale vegetable farming system in a peri-urban agricultural area, China
This study monitored the balances of heavy metal elements such as Cu, Pb, Zn, and Cd and evaluated pollution potential of them in a small-scale vegetable farming system in the peri-urban area of Nanjing, China during July 2003-July 2004. Results indicated that the inputs of the heavy metals via fertilization and irrigation were the sources of the heavy metals in the system. Organic fertilization contributed more than 98％ of the heavy metals input to the system. In contrast, the annual outputs were low and less than 10％ of the inputs. Compared to the national safety standards, the concentrations of Cu, Pb, Zn and Cd in soils and vegetables were lower, indicating that the vegetable farming system was safe under the present circumstances. The evaluation of the heavy metal accumulation in combination with atmospheric deposition showed the soil might have the long-term risk of Cu, Zn and Cd contamination. The magnitude of the risk depended on intensity of soil cultivation. The intensive cultivation can result in the accumulation of the heavy metals in vegetable soils close to the Chinese environmental quality standards for soils within several decades.
Balances of heavy metals Risk evaluation Peri-urban area Small-scale vegetable farming
Huang B Xu Y. X Wang H. J Shi X. Z Yu D. S Oborn I
State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy Swedish University of gricultural Sciences, SE-750 07 Uppsala, Sweden
国际会议
第九届痕量元素生物地球化学国际会议(9th International Conference on the Biogeochemistry of Trace Elements)
北京
英文
69-70
2007-07-15（万方平台首次上网日期，不代表论文的发表时间）