矿产保护规范了自然有机碳的长期全球保存
Jordon D Hemingway1, Daniel H Rothman2, Katherine E Grant3
1Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA, USA. jordon_hemingway@fas.harvard.edu.
Nature
|June 14, 2019
概括
矿物相互作用保护土壤和沉积物中的有机碳, 这项研究揭示了矿物保护是碳封存的关键,
科学领域:
- 地质化学
- 生物地质化学
- 气候科学
背景情况:
- 光合作用和呼吸调节大气组成和气候.
- 有机碳封存对于大气中的氧气和二氧化碳平衡至关重要.
- 有机碳保存的两个建议机制是选择性保存和矿物相互作用.
研究的目的:
- 研究有机碳保存机制的全球相对重要性.
- 分析矿物质矩阵在长期有机碳稳定性的作用.
- 了解有机碳的保存如何影响地球的气候在地质时间.
主要方法:
- 编制有关有机碳激活能量的全球数据集.
- 分析土壤,沉积物和溶解有机碳中的放射性碳衰老.
- 对结合强度的多样性和有机矿物结合的评估.
主要成果:
- 在含有矿物质的样本中,激活能量分布随着时间的推移而扩大,这表明结合强度的多样性增加.
- 与未结合的有机碳相比,矿物结合的有机碳在数千年内表现出更大的持久性.
- 证据支持矿物保护在有机碳保护中的重要作用.
结论:
- 矿物保护是全球连贯且占主导地位的有机碳保护机制.
- 有机矿物键的形成有助于有机碳的长期稳定性.
- 了解古代沉积物中的结合强度多样性是解读过去气候变化的关键.
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