期刊
CHEMOSPHERE
卷 237, 期 -, 页码 -出版社
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.chemosphere.2019.124480
关键词
Degradable chelator; Phytoextraction; Amaranthus hypochondriacus L.; Bioavailable Cd; Soil enzyme activity
资金
- National Key Research and Development Program of China [2016YFD0800806]
- National Natural Science Foundation of China [41771525]
- STU scientific research foundation for talents [NTF19025]
The use of degradable chelating agent to enhance phytoextraction is a promising and low-cost method for remediation of heavy metals-polluted soil. However, very limited information is available regarding the effect of chelating agent combinations on plant growth and its capacity to extract metals. In this study, a pot experiment was conducted to evaluate the applicability of [N, N]-bis glutamic acid (GLDA), nitrilotriacetic acid (NTA), [S, S]- ethylenediamine disuccinic acid (EDDS), and citric acid (CA) alone and in combination to enhance the phytoextraction efficiency of amaranth (Amaranthus hypochondriacus L) in two Cd-contaminated agricultural soils (S-1 soil 2.12 mg/kg and S-2 soil 2.89 mg/kg; the environmental standard value of Cd in agricultural soils in China is lower than 0.8 mg/kg). The results showed that, except for EDDS, other treatments had no obvious effect on plant biomass, and even promoted biomass increase to reach 1.06 (S-1), 2.07 (S-2) g/pot. The increase in total Cd extraction amount by 5 mM of single chelators GLDA and NTA reached 3.87 and 2.81 (S-1), and 3.28 and 2.50 (S-2) times that of the control group, respectively. For complexed chelating agents, G-N (GLDA + NTA) combinations (GLDA = 3 mM, NTA = 2 mM) extracted the highest amount of Cd compared with other treatments, reaching 0.36 and 0.52 mg/pot (4.50 and 3.71 times that of the control group), respectively. The order of extraction amount was G-N > GLDA > NTA > G-E (GLDA + EDDS) > G-C (GLDA + CA) > CA (5 mM total Cd concentration). Moreover, soil enzyme activity of G-N treatment increased significantly compared to that of the control group, indicating the great application potential of a composite chelating agent relative to a single chelating agent. Therefore, degradable chelators, especially the G-N combination, can effectively increase the available Cd content and greatly enhance the ability of plants to absorb and transport Cd in soils. (C) 2019 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据