在被稳定同位素所限制的泥炭地中,沉积和氧化还原转化过程受到稳定同位素的限制
Chuxian Li1, Martin Jiskra2, Mats B Nilsson3
1Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden. chuxian.li@slu.se.
Nature communications
|November 15, 2023
概括
泥炭地中的 (Hg) 通过光驱动的过程被释放回大气中,光还原发出沉积的Hg的30%. 暗氧化也影响了泥炭土中的气态水平.
科学领域:
- 环境化学环境化学
- 生物地质化学生物地质化学
- 生态系统科学 生态系统科学
背景情况:
- 泥炭地是大气中的 (Hg) 的重要沉积点.
- 泥炭地中的甲基化产生神经毒性甲基Hg,影响下游生态系统.
- 了解Hg氧化还原转换对于预测其环境命运至关重要.
研究的目的:
- 为了研究在北极泥炭地中沉积后的氧化还原转化过程.
- 量化不同过程对泥炭地释放的的贡献.
- 为了确定光驱和暗氧还原反应对Hg循环的作用.
主要方法:
- 在泥炭地样本中分析的度和同位素特征.
- 应用同位素质量平衡来确定Hg转换路径.
- 在水表上方和下方的Hg氧化还原过程的研究.
主要成果:
- Hg的光降解 (II) 是主要的过程,将30%的沉积Hg释放回大气中.
- 水平面上方的暗无生物氧化减少了泥炭土中的气态Hg(0) 度.
- 在水表以下,降雨的光降低,而不是泥炭土,可能会产生气态Hg超和.
结论:
- 光驱动和黑暗的氧化还原过程显著影响了泥炭地中的Hg循环.
- 这些发现促进了对Hg命运的理解,包括潜在的动员和甲基化.
- 皮特兰Hg释放主要通过光还原和非生物氧化过程控制.
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