温和的加热使780万年前的沉积物有机物变得生物可用
Shuchai Gan1,2,3, Verena B Heuer1, Frauke Schmidt1
1MARUM - Center for Marine Environmental Sciences and Department of Geosciences, University of Bremen. Leobener Straße 8, D-28359 Bremen, Germany.
Science advances
|August 20, 2025
概括
海洋沉积物有机物分解是由热量驱动的, 无生物热过程释放可生物利用的化合物,影响长期碳封存和全球碳循环.
科学领域:
- 地质化学
- 微生物学
- 有机地化学
背景情况:
- 海洋沉积物储存大量反抗性的有机物质.
- 在极端深度和极端温度下存在微生物.
- 在这些环境中供应可生物利用基质的机制尚不清楚.
研究的目的:
- 研究温度对海洋沉积物中溶解有机物 (DOM) 的转化作用.
- 在模拟埋葬条件下阐明生物可用基质生成的途径.
主要方法:
- 在20°C至85°C的温度下化780万年前的海洋沉积物.
- 使用3D光光谱和超高分辨率质谱分析溶解有机物质.
- 对金属离子释放和DOM生物可用性的监测.
主要成果:
- 在35°C时,释放出具有低生物可用性的类DOM.
- 在55°C,非生物分解产生更小,更可生物利用的DOM,增强发酵.
- 在85°C,无生物过程通过绕过发酵,从含有的化合物中产生可变的H2和酸盐.
结论:
- 在海洋沉积物中的耐火有机物中,无生物热过程至关重要.
- 温度驱动的DOM转换会影响微生物活动和基质的可用性.
- 这些发现有助于人们更好地了解长期的碳封存和全球碳循环.
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