在季节性淹水沉积物中增加的甲基产量:从DOM分子组成的洞察力
Xian Zhou1, Tianrong He1, Yongguang Yin2
1Key Laboratory of Karst Georesources and Environment (Guizhou University), Ministry of Education, College of Resources and Environmental Engineering, Guizhou University, Guiyang 550025, China.
Journal of hazardous materials
|January 9, 2025
概括
由于独特的溶解有机物 (DOM) 质量,季节性洪水地区 (SIA) 显示出更高的甲基 (MeHg) 产量. 包括成分和结构在内的SIA DOM特征显著推动了沉积物中的MeHg合成.
科学领域:
- 环境化学环境化学
- 水生生态学 水生生态学
- 生物地质化学生物地质化学
背景情况:
- 季节性洪水地区 (SIA) 是水生生态系统中甲基 (MeHg) 生产的热点.
- 在SIA沉积物中溶解有机物 (DOM) 质量对MeHg生产的具体作用仍然不清楚.
- 了解这些因素对于管理湿地的污染至关重要.
研究的目的:
- 研究DOM在SIA沉积物的分子组成和结构特征.
- 为了确定SIA DOM质量对MeHg产量的影响.
- 阐明DOM属性与金属污染湿地中的MeHg合成之间的关系.
主要方法:
- 在金属污染的高原湿地实地采样,比较SIA和永久淹水地区 (PIA).
- 实验室微观宇宙实验以评估DOM生物降解性,吸附性和对Hg的结合亲和力.
- 通过Desulfomicrobium escambiense对MeHg合成的分析和使用部分最小平方路径建模 (PLS-PM) 的量化.
主要成果:
- 与PIA相比,SIA中的DOM表现出更高的体样分数,分子量和生物可用性,但较低的染色体DOM和蛋白质样分数.
- SIA DOM更容易生物降解,具有更高的Hg (II) 吸附能力和较低的结合亲和力.
- 与SIA DOM相比,MeHg合成高出了29.6倍,而DOM组成强烈影响了沉积物孔水中的MeHg水平.
结论:
- 在SIA沉积物中的DOM分子组成和结构是MeHg产量升高的关键驱动因素.
- 在SIA内部,DOM质量的适应性变化为MeHg合成创造了有利的条件.
- 这些发现为季节性淹水的水生系统中高MeHg水平提供了机械解释.
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