溶解有机物中的类成分抑制了沉积物对的封存
Bolin Li1, Zhongwu Li2, Jia Chen1
1College of Environmental Science and Engineering, Hunan University, Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China.
Journal of environmental sciences (China)
|September 21, 2024
概括
溶解有机物 (DOM) 对湖泊中的 (Cd) 运输产生影响. 类似的DOM成分抑制了沉积物对Cd的分离,从而增加了其生物可用性.
科学领域:
- 环境化学环境化学
- 地质化学 地质化学
- 水生化学 水生化学
背景情况:
- (Cd) 污染是中国湖泊的一个重大问题.
- 溶解有机物 (DOM) 在沉积物-水界面调节Cd的运输方面发挥着至关重要的作用.
研究的目的:
- 研究不同DOM组件对沉积物-水界面Cd (II) 流动性的影响.
- 了解DOM-Cd相互作用背后的机制及其对Cd封存的影响.
主要方法:
- 使用光火加上并行因子分析 (EEM-PARAFAC) 进行DOM组件的表征.
- 在不同DOM类型 (富尔维酸,α-氨酸,二甲硫酸盐) 的存在下,沉积物对Cd (II) 吸附的分析.
- 使用富里埃变换红外光谱 (FTIR) 和复杂反应模型对沉积物表面相互作用的研究.
主要成果:
- 陆地衍生的DOM (富尔维酸) 和本土衍生的DOM (α-氨酶) 抑制了Cd(II) 结合分别为42.5%和5.8%.
- 人类衍生的DOM (二二二硫酸盐) 增加了Cd(II) 沉积物的吸附量,增加了2.8%.
- 发现类似的DOM成分与沉积物竞争Cd (II) 吸附点,抑制Cd封存并增加生物可用性.
结论:
- DOM的类型显著影响了沉积物-水界面上的Cd(II) 流动性.
- 类DOM成分是减少Cd封存和提高Cd在水生系统中的生物可用性的关键驱动因素.
- 了解DOM-Cd相互作用对于管理湖泊中的Cd污染至关重要.
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