生命和地球大气层的演变
James F Kasting1, Janet L Siefert
1Department of Geosciences, 443 Deike, The Pennsylvania State University, University Park, PA 16802, USA. kasting@essc.psu.edu
Science (New York, N.Y.)
|May 11, 2002
概括
像蓝藻和藻类这样的微生物进行光合作用,产生氧气和固定. 早期的无氧细菌可能已经调节了早期的地球.
科学领域:
- 天体生物学和进化生物学
- 生物地质化学循环的过程
- 微生物生态学 微生物生态学
背景情况:
- 光合作用,用于能量和氧气生产的光采集过程,是陆地植物的一个关键特征,起源于古老的蓝藻细菌.
- 今天,蓝藻和微观藻类对大气中的氧气和海洋固定的至关重要.
- 早期地球的大气和气候在氧化事件之前受到微生物生命的显著影响.
研究的目的:
- 探索微生物在地球大气层演变中的关键作用.
- 了解早期微生物生命对气候调节的贡献.
- 突出生物进化和大气变化的相互联系.
主要方法:
- 对光合作用和无氧微生物的进化历史的回顾.
- 分析由微生物活动驱动的生物地化学过程.
- 早期地球环境条件和微生物影响的重建.
主要成果:
- 菌的光合作用能力被转移到植物,塑造了陆地生态系统.
- 海洋微生物对全球氧气和循环至关重要.
- 无氧细菌可能产生甲,维持地球早期温暖的气候.
结论:
- 地球大气层的进化与其生物群的进化密切相关.
- 微生物的创新,从氧光合作用到甲基生成,已经深刻地塑造了行星的可居住性.
- 了解古代微生物的作用是理解地球系统演变的关键.
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