来自不同湖泊的溶解有机物质的光谱性质和金属结合行为的分子重量依赖的差异
Keli Yang1, Yaoling Zhang2, Jiaoyu Peng1
1Key Laboratory of Green and High-end Utilization of Salt Lake Resources, Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining, China; Qinghai Engineering and Technology Research Center of Comprehensive Utilization of Salt Lake Resources, Xining, China.
The Science of the total environment
|June 26, 2024
概括
来自三个湖泊的溶解有机物 (DOM) 分数显示了各种金属结合. 高分子量DOM通常更好地结合金属,但查卡湖
科学领域:
- 环境化学环境化学
- 水生化学 水生化学
- 有机地化学 有机地化学
背景情况:
- 溶解有机物 (DOM) 显著影响水生环境中的金属物种和流动性.
- 了解DOM的作用对于预测金属命运和湖泊运输至关重要.
研究的目的:
- 研究埃尔海湖,科科诺尔湖和查卡湖中大小分化的DOM的光谱特性和金属结合行为.
- 为了比较铜 (Cu(II)) 和 (Pb(II)) 与不同 DOM 分数的结合亲和力.
主要方法:
- DOM的大小分成高分子量 (HMW) 和低分子量 (LMW) 分数.
- 测量溶解有机碳 (DOC) 和光谱特性 (光).
- 金属定位实验与激发发射矩阵 (EEM) -平行因子 (PARAFAC) 建模相结合.
主要成果:
- 与其他湖泊相比,查卡湖DOM的DOC和光度较高,但碳水化合物含量较低.
- HMW-DOM 分数被丰富了芳香,碳水化合物和类似蛋白质的物质.
- 类似胺的成分显示较强的结合Cu(II),而类似蛋白质的成分则更喜欢Pb(II).
- 金属-DOM结合常量 (Log KM) 在湖泊和DOM分数之间有所不同,HMW-DOM通常显示出更高的亲和力,除了查卡湖.
结论:
- 自然DOM在光谱特征和金属结合能力方面表现出显著的异质性.
- DOM的分子组成决定了它与不同金属离子的相互作用.
- 这些发现提高了对DOM金属相互作用及其在水生生态系统中的环境影响的理解.
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