铁 (水) 氧化物和有机合物介于Cr (VI) 污染的土中合物结合的调动
Ting Liu1, Ran Wei1, Jingjing Li1
1Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Provincial Key Laboratory of Agricultural & Rural Pollution Abatement and Environmental Safety, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, 510642, China.
Environmental pollution (Barking, Essex : 1987)
|October 2, 2024
概括
化颗粒显著影响 (Cr) 运输和大米在污染的土壤中的积累. 了解Cr-合物相互作用对于管理土壤和地下水污染至关重要.
科学领域:
- 环境科学 环境科学
- 土壤科学 土壤科学
- 地质化学 地质化学
背景情况:
- (Cr) 污染对土壤和地下水系统构成风险.
- 体粒子运输是六价 (Cr(VI)) 迁移和转化的一个关键因素.
- 米等作物中的cr积累受土壤cr物种化和流动性的影响.
研究的目的:
- 为了研究合物和颗粒结合的Cr在米积累中的作用.
- 了解不同氧化还原条件和生长阶段下的Cr迁移和转变.
- 量化大小解析的Cr与土壤颗粒的关联.
主要方法:
- 实验模拟了Cr (VI) 污染的米土壤条件.
- 传输电子显微镜 - 能量分散光谱 (TEM-EDS) 用于材料识别.
- 不对称的流场 - 流分离 (AF4) 用于尺寸解析的粒子分析.
- 纳米粒子零价值铁 (nZVI) 应用程序来评估氧化还原效应.
主要成果:
- 在水生长过程中,土壤13-29%的Cr是水分散型合物 (100-1000nm) 结合.
- 与体结合的Cr主要与有机物和铁 (Fe) 在Fe (氧化水) -粘土复合物 (125-350 nm) 中有关.
- 纳米粒子零价值铁 (nZVI) 降低了合物和纳米粒子结合的Cr;再氧化释放了Cr.
- 合物结合的Cr度与合物结合的 (Mn) 有正相关.
- 米粒中的Cr含量与合物结合的Cr含量显著相关.
结论:
- 与体结合的Cr,特别是与Fe-氧化物-粘土复合物相关的Cr,是土中的主要载体.
- 氧化还原条件和土壤再氧化显著影响Cr通过合体运输的流动性.
- 与体结合的Cr是直接影响米粒Cr积累的关键因素.
- 这项研究强调了合物-铁相互作用在水土壤中Cr的地球化学循环中的重要性.
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