地球系统中溶解有机物质的全球模式和驱动因素:从H/C和O/C比率的见解
Ang Hu1, Lei Han1, Xiancai Lu2
1Key Laboratory of Lake and Watershed Science for Water Security, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China.
Fundamental research
|January 30, 2026
概括
溶解有机物 (DOM) 的分子组成在全球范围内有所不同. 这项研究分析了各种环境中的H/C和O/C比率,揭示了气候和pH等关键驱动因素,以了解全球碳循环.
科学领域:
- 环境化学环境化学
- 生物地质化学生物地质化学
- 有机地化学 有机地化学
背景情况:
- 溶解有机物 (DOM) 是一种复杂的分子混合物,对全球碳循环至关重要.
- 了解DOM在地球系统和气候中的分子特性是必不可少的,但仍然不完整.
研究的目的:
- 使用H/C和O/C比率全面分析DOM的分子特性.
- 调查DOM分子组成在各种环境系统和气候梯度中的全球分布和驱动因素.
主要方法:
- 编制了来自317项水,土地,植物,石油和大气系统的317项研究的2,995个DOM样本.
- 分析了丰富度加权的平均H/C和O/C比率来描述DOM分子性质.
- 与环境因素 (pH,溶氧,C/N含量) 和极端气候相相关的DOM比率.
主要成果:
- 与其他系统相比,DOM H/C 比率在水 (1.15) 和陆地 (1.20) 系统中较低.
- 水温比率遵循陆地到海洋连续趋势:雪>冰川>海洋>淡水/土壤>地下水.
- 在H/C比率中观察到U形的度图案,在中度 (40°-50°) 中的最小值.
- DOM比率受到pH值,溶解氧,C/N含量以及降水和温度等气候因素的显著影响.
结论:
- 环境和气候因素是全球DOM分子组成的主要驱动因素.
- 这种对DOM分布的分子层次理解有助于预测全球变化下的碳循环动态.
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