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大规模的陆地生态系统破坏在古世 - 世热极限开始时发生
Mei Nelissen1,2, Debra A Willard3, Han van Konijnenburg-van Cittert2
1Department of Ocean Systems, Royal Netherlands Institute for Sea Research, Den Burg 1790 AB, the Netherlands.
概括
在古世 - 世热极值 (PETM) 中,广泛的植被变化和生态系统崩,类植物在全球范围内取代森林. 这表明在事件期间有重大陆地生态系统干扰和积极的碳循环反.
科学领域:
- 古气候学 古气候学
- 古生态学 古生态学
- 地质化学 地质化学
背景情况:
- 古世 - 世热极值 (约56亿年前) 是一个全球快速变暖和大规模碳排放的时期.
- 在PETM期间已知水文和土壤侵蚀事件,但与植被和碳循环变化的联系尚不清楚.
研究的目的:
- 在PETM期间使用有机微化石证据调查植被和碳循环变化.
- 了解陆地生态系统反在PETM碳同位素游览 (CIE) 中的作用.
主要方法:
- 从沉积物记录中分析有机微化石 (花粉,子,微炭).
- 在多个全球地点之间植被变化的平流图相关性.
- 碳循环模型模拟包括陆地生态系统反.
主要成果:
- 一个全球性的,全球性的.
- 棘的棘是一种棘.
- 表明在PETM的CIE期间,从针叶树林转向开拓鸟植被.
- 经常出现的物理干扰 (土壤侵蚀,野火) 和重新加工的有机物质表明生态系统的广泛不稳定性.
- 模型模拟显示,在CIE期间,显著的生物质损失和土壤有机物氧化作为积极的反作用.
结论:
- 在全球范围内,陆地生态系统在PETM期间经历了严重的干扰和崩.
- 植被变化和生态系统反在放大PETM碳循环扰乱方面发挥了关键作用.
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