溶解有机物 (DOM) - - 在水浸的土中,的流动性和生物可用性的驱动变化
Mingming Tao1, Xianlin Ke2, Jingnan Ma3
1Sino-Danish College, University of Chinese Academy of Sciences, Beijing 101408, China; Department of Plant and Environmental Science, Faculty of Science, University of Copenhagen, Taastrup DK-2630, Denmark; Sino-Danish Centre for Education and Research (SDC), Beijing 101408, China.
Journal of hazardous materials
|March 30, 2025
概括
溶解有机物 (DOM) 最初增加了在土中的 (Cd) 流动性,但后来通过促进硫化物封存来减少它. 硫酸盐修改增强了这种效果,尽管低Cd水平可以逆转DOM.
科学领域:
- 环境化学环境化学
- 土壤科学 土壤科学
- 地质化学 地质化学
背景情况:
- 在土中, (Cd) 的流动性和生物可用性受到溶解有机物 (DOM) 的显著影响.
- 控制这种相互作用的精确机制,特别是在水浸的条件下,需要进一步阐明.
- 了解这些过程对于管理农业系统中Cd污染至关重要.
研究的目的:
- 调查溶解有机物 (DOM) 和硫酸盐修正在调节水浸的土中的 (Cd) 流动性和生物可用性的作用.
- 阐明底层机制,包括铁 (Fe) 和硫 (S) 循环的影响.
- 评估不同Cd水平对DOM-硫酸盐相互作用的影响.
主要方法:
- 在浸水条件下进行了为期90天的土壤化实验.
- 修改包括在不同度下溶解有机物 (DOM) 和硫酸盐.
- 监测的关键参数包括溶解有机碳 (DOC),pe+pH,Fe/S相关参数以及Cd流动性和生物可用性的指标.
主要成果:
- 此外,DOM最初增加了Cd的流动性,由于脱落和复杂化,但后来通过促进硫化物介导的Cd封存来减少它.
- 硫酸盐的应用增强了硫化物介导的Cd分离效应.
- 在低Cd土壤中,由于Cd/DOM比率低,DOM在后期增加了生物可用性,而硫酸盐减轻了这种影响.
- 在高Cd土壤中,DOM的流动性降低,但由于竞争性吸附和Fe转化,在45天后可用性增加.
结论:
- 溶解有机物在调节土壤中的动态方面发挥着双重作用,受化时间,Cd水平和硫酸盐存在的影响.
- 由Fe-S降解细菌驱动的硫化物介导的封存是DOM诱导的Cd固定化的关键机制.
- 硫酸盐修改通常会增强Cd固定,为控制Cd污染提供一种潜在的策略,但相互作用是复杂的,并且取决于环境.
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