ベースアルト水層における水素ベースの微生物生態系に対する証拠
1R. T. Anderson, Department of Civil and Environmental Engineering, University of Massachusetts, Amherst, MA 01003, USA. F. H. Chapelle, U.S. Geological Survey, Columbia, SC 29210-7651, USA. D. R. Lovley, Department of Microbiology, University of Mass.
まとめ
玄武岩-地下水相互作用による水素生成は,地表深部の生命を支える可能性は低い. 実験では,環境に関係のないpHレベルでの,最小の,一時的な水素生成が示されています.
科学分野:
- 地質化学 地質化学
- 微生物学 微生物学とは
- 天体生物学 アストロバイオロジー
背景:
- 玄武岩と地下水との相互作用によって生成される水素は,地球上の地下微生物の生命と潜在的に他の惑星のためのエネルギー源である.
- 以前の研究では,この水素生成が微生物生態系を維持できると示唆されていました.
研究 の 目的:
- 地下生命のための持続可能なエネルギー源として,玄武岩-地下水相互作用による水素生産の可行性を調査する.
主な方法:
- バザルトと水の実験室インキュベーションで, pH 値が異なる.
- 水素の生産速度と持続可能性を評価するための地化学分析.
- 実験条件の環境関連性の評価.
主要な成果:
- 水素の生成は,環境的に重要なアルカリ性pHでベースタルトから観察されませんでした.
- 軽微で一時的な水素生成は,より低い,無関係なpHで発生しました.
- 地化学モデリングは,報告された水素生産率は,地質学的時間尺度では持続可能ではないことを示しました.
結論:
- ベースアルト-地下水相互作用による水素生成は,地表深層の微生物の代謝を支える可能性は低い.
- 地球外生命と地球深層生命のための提案されたエネルギー源は,研究された条件下では実行不可能です.
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