地球の段階的な酸素化は,地球生物化学循環の固有の性質である
Lewis J Alcott1, Benjamin J W Mills2, Simon W Poulton2
1School of Earth and Environment, University of Leeds, Leeds LS2 9JT, UK. eelja@leeds.ac.uk.
まとめ
地球の酸素化は 3つの段階で行われました 内部生地化学的なフィードバックが 酸素の増加を促し 光合成が進化した後に 徐々に酸素が増えたのです
科学分野:
- 地化学
- 生地化学
- 古代気候学
背景:
- 地球の大気と海洋は,古プロテロゾイク,新プロテロゾイク,古プロテロゾイク時代に3つの主要な酸素化イベントを経験しました.
- これらの酸素化の段階は 生物圏に大きな影響を及ぼしましたが その主な原因については 議論が続いています
- これまでの仮説では 生物学的または地質学的な革命が 段階的な酸素増加の原因だと考えられていた.
研究 の 目的:
- 地球の段階的な酸素化の要因を調査する
- 観察された酸素化の段階を説明するために,外部からの強制が必要かどうかを判断する.
- 炭素,酸素,の長期の生地化学サイクルをモデル化するために
主な方法:
- 理論モデルの開発と応用
- 長期生地化学サイクルにおける内部フィードバックの分析
- 炭素,酸素,の相互作用のシミュレーション
主要な成果:
- このモデルは,段階的な酸素化が内部生地化学フィードバックの自然な結果であることを示しています.
- 酸素化の段階のタイミングや大きさを説明するために,特定の外部の強制的なイベントは必要ありません.
- この結果は,酸素光合成の進化に伴う 惑星表面の漸進的な酸素化と一致している.
結論:
- 地球の酸素化現象は,炭素,酸素,の循環における内部フィードバックによって説明される.
- 段階的な酸素増加は 地球の生地化学システムの本質的な性質です
- 酸素 fotosynthesisの進化は,観察された地質学的記録と一致する徐々に酸素化のプロセスを開始しました.
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