在海洋中低估了陆地溶解有机碳的输入
Yuanbi Yi1, Andrew J Tanentzap2,3, Chen He4
1Department of Ocean Science and Center for Ocean Research in Hong Kong and Macau, The Hong Kong University of Science and Technology, Hong Kong 999077, China.
概括
陆地溶解有机物 (DOM) 对海洋的贡献是以前认为的1.7-2.5倍. 这一发现需要对全球碳循环模型进行调整,以提高准确性.
科学领域:
- 环境化学环境化学
- 海洋学 海洋学 海洋学
- 生物地质化学生物地质化学
背景情况:
- 陆地溶解有机物 (DOM) 在海洋碳池中的作用仍然不太清楚.
- 之前的追踪方法因生物标记物不稳定性,无法区分的同位素和类似的化学成分而面临挑战.
研究的目的:
- 量化陆地DOM对海洋有机碳池的贡献.
- 为了识别和跟踪从河流运输到海洋的陆地分子.
- 为了完善全球碳循环模型.
主要方法:
- 使用高性能液态色谱与超高分辨率质谱相结合.
- 确定了269种分子配方 (MF),可能起源于陆地来源.
- 进行了化实验,以评估MF对降解的抵抗力.
- 分析了全球河流,边缘海洋和开放海洋中的MF分布.
主要成果:
- 陆地DOM的贡献是以前估计的1.7至2.5倍.
- 已识别的陆地MF具有耐降解性,分布广泛.
- 据估计,海洋DOM的16.7%至25.0%来自河流.
结论:
- 陆地DOM在海洋碳池中扮演的角色比以前认为的要重要得多.
- 特定的陆地分子是稳定的,并在海洋环境中广泛存在.
- 当前的全球碳循环模型可能低估了陆地对海洋的投入.
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