森林地表土壤溶解有机物中的空间和分子变化,由FT-ICR质谱检测揭示
Ming Sheng1, Shuang Chen1, Cong-Qiang Liu1
1Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, 300072, China.
The Science of the total environment
|June 28, 2023
概括
森林土壤溶解有机物 (DOM) 根据度而异. 高度显示更多的植物衍生的,稳定的化合物,而低度有更多的微生物衍生的碳. 这会影响全球碳循环.
科学领域:
- 环境科学 环境科学
- 地质化学 地质化学
- 土壤科学 土壤科学
背景情况:
- 森林土壤对全球碳循环至关重要,溶解有机物 (DOM) 是最大的活跃陆地碳池.
- 土壤DOM是一种复杂的多种化合物的混合物,影响土壤发育,微生物活动和营养循环.
- 了解森林土壤DOM的分子组成和空间分布是解读其在碳循环中的作用的关键.
研究的目的:
- 研究不同度的森林土壤中溶解有机物 (DOM) 的空间和分子变化.
- 阐明中国森林保护区中DOM分子组成的大规模分布模式.
主要方法:
- 使用里埃转换离子循环子共振质谱法 (FT-ICR MS) 来分析DOM分子组成.
- 选择了6个主要的森林保护区,跨越中国的度梯度进行样本采集.
- 使用网络分析可视化土壤有机物分子的复杂性和多样性.
主要成果:
- 芳香类分子在高度森林土壤中被丰富,而酸/酸类,碳水化合物类和不和碳化合物分子在低度土壤中占主导地位.
- 在所有研究的森林土壤中,类化合物占DOM的比例最高.
- 高度的土壤呈现出更高的芳香等价值和指数,表明更多的植物衍生的耐火有机物,而低度的土壤则由微生物衍生的碳占主导地位.
- 在所有样本中,CHO和CHON化合物构成了大多数已识别的DOM分子.
结论:
- 森林土壤DOM分子组成表现出显著的度变化,受植物投入和微生物过程的影响.
- 高度的土壤含有更多的反抗性,来自植物的有机物质,而低度的土壤的特点是微生物加工的碳.
- 这项研究为大规模森林土壤有机物分布提供了分子层面的理解,有助于资源管理和碳循环研究.
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