Heavy metals in soil and plants after long-term sewage irrigation at Tianjin China: A case study assessment
Heavy metals in soil and plants after long-term sewage irrigation at Tianjin China: A case study assessment
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中国天津长期污水灌溉后土壤和植物中的重金属：案例研究评估
DOI：
10.1016/j.agwat.2016.03.013
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发表时间：
2016-06-01
影响因子：
6.7
通讯作者：
Goodman, Robbin Cole
中科院分区：
文献类型：
--
作者：
Meng, Weiqing;Wang, Zuwei;Goodman, Robbin Cole
由于淡水资源对农业灌溉的限制，近三十年来，我国特别是北方地区将污水作为重要的补充和替代水资源用于农田灌溉。然而，人们越来越关注食品安全和健康风险，因此，进行了一项案例研究，以了解污水灌溉对土壤和植物中重金属浓度的长期影响。污水污泥，土壤和植物样品收集和分析的重金属浓度。结果表明，与清水灌溉土壤相比，污水灌溉土壤中镉、铜、铅、锌、镍、铬、砷和汞的含量要高得多。表层土壤（0-20 cm）重金属含量明显高于下层土壤。天津市污水灌溉区土壤中存在严重的重金属污染。污水灌溉小麦对重金属有明显的积累。与小麦植株其他部位相比，小麦根系中Cd、Cr、Pb、As的含量较高，说明小麦根系对Cd、Cr、Pb、As的吸收能力较强，可能具有明显的屏障效应。基于重金属的土壤-植物转移因子，蔬菜对Cd有较强的积累效应。总体而言，土壤中Cd、Pb、Ni、Cr和As的含量均低于国家允许的安全限值。蔬菜中Cd、Pb和As的平均含量高于国家安全限值，Cu、Zn和Cr的平均含量低于国家安全限值。因此，为了确保食品安全和使用污水灌溉，需要持续监测和污染控制。皇冠版权所有（C）2016由Elsevier B.V.出版。保留所有权利。
Due to the constraints of freshwater for agricultural irrigation, sewage water has been used in farmland irrigation as an important supplement and alternative water resources during the past three decades in China, especially in northern areas. However, there is increasing concern about food safety and health risks, hence, a case study was undertaken to understand the long-term effect of sewage irrigation on heavy metal concentrations in soil and plants. Sewage sludge, soil and plant samples were collected and analyzed for heavy metals concentrations. Results showed that sewage irrigated soil contained much higher concentrations of Cd, Cu, Pb, Zn, Ni, Cr, As and Hg compared to clean water irrigated soil. The heavy metal content of the topsoil (0-20 cm) was much higher than that of the subsoil. Significant heavy metal (Cd, Zn and Hg) pollution has occurred in soils of areas that had been using untreated waste water irrigation in Tianjin, China. There were significant accumulations of heavy metals in wheat that used sewage irrigation. Compared with the other parts of the wheat plants, the higher contents of Cd, Cr, Pb and As in the roots indicated that roots had a strong absorption ability and maybe cause an obvious barrier effect. Based on the soil to plant transfer factor of heavy metals, there is a strong accumulation effect of Cd in vegetables. Overall, the concentrations of Cd, Pb, Ni, Cr and As were lower than the national permitted safety limits in soil. Mean Cd, Pb and As concentrations in vegetables were higher than the national safety limits, whereas the mean concentrations of Cu, Zn and Cr were below Chinese national safety limits. Therefore, in order to ensure food safety and use of sewage for irrigation, continuous monitoring and pollution control is needed. Crown Copyright (C) 2016 Published by Elsevier B.V. All rights reserved.