使用高分辨率质谱测量揭示沉积物-水界面上溶解有机物质的组成和转化
Jinfeng Ge1, Yulin Qi1,2,3, Sen Xu1
1Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China.
Journal of the American Society for Mass Spectrometry
|September 17, 2024
概括
溶解有机物 (DOM) 的组成因沉积物-水界面的盐度而异. 盐度较低的水域表现出更高的多样性,而盐度较高的水域表现出更高的生物可用性,影响流域生物地质化学.
科学领域:
- 环境化学环境化学
- 生物地质化学生物地质化学
- 分析化学 分析化学
背景情况:
- 沉积物-水界面的溶解有机物 (DOM) 交换是流域生物地球化学的关键.
- DOM的分子组成决定了它的转化过程.
- 高分辨率质谱 (HRMS) 对于分析DOM组成至关重要.
研究的目的:
- 分析不同盐度的沉积物-水界面上的DOM组成特征.
- 了解盐度如何影响DOM分子多样性,重量,和和生物可用性.
- 在不同的盐度条件下阐明DOM转换路径.
主要方法:
- 在沉积物-水界面使用高分辨率质谱法 (HRMS) 分析DOM成分.
- 在中国北部的三个不同盐度水平中对DOM特征进行比较.
- 计算H/C和O/C比率来表征化学转化.
主要成果:
- 与盐度较高的海水相比,低盐度的内陆水域表现出更大的DOM分子多样性和更高的分子重量.
- 高盐度的海水显示DOM和和生物可用性增加.
- 在低盐度水域 (陆地/人类影响) 中,CHOS物质更为普遍,而CHO和CHNO物质则在高盐度水域 (微生物影响) 中占主导地位.
- 确定了包括甲基化,化,脱碳化和还原在内的化学转化.
结论:
- 人力资源管理系统 (HRMS) 在各种环境条件下,为沉积物-水界面的DOM过程提供了精细的见解.
- 盐度显著改变DOM分子组成和转化途径.
- 这些发现有助于更好地理解沉积物有机物源-沉机制.
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