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3,500万年前から現在までの微生物マットにおける炭素固定のモデル

L J Rothschild¹, R L Mancinelli

¹Solar System Exploration Branch, NASA-Ames Research Center, Moffett Field, California 94035, USA.

|June 21, 1990

まとめ

初期の生活初期の生活

科学分野:

パレオントロジー・パレオントロジー
エコロジーエコロジーエコロジー
地質化学地質化学

背景:

生物学的炭素固定は,世界の炭素循環と生態学にとって極めて重要です.
ストロマトライトは,化石化した微生物のマットで,3,500万年前からの初期の炭素固定を記録し,プロテロゾーイク時代に豊富に存在していました.
ストロマトライトの豊富さは,捕食,競争,または環境の変化のために減少した可能性があります.

研究の目的:

大気中の二酸化炭素 (CO2) レベルが,古代の微生物マットにおける生物学的炭素固定率に与える影響を調査する.
プレカンブリア期におけるストロマトライトの衰退における炭素制限の役割を調査する.

主な方法:

古代のストロマトライトの類似品として,現代の微生物マットを利用しました.
異なる大気中のCO2濃度下での炭素固定速度を比較し,過去の条件をシミュレートした.

主要な成果:

炭素固定率は,初期の地球の特徴である大気中のCO2レベルが上昇したときに高かった.
微生物のマット炭素固定は,おそらく,初期のプレカンブリア時代には炭素限定ではなかった.
プレカンブリア紀の終わりに無機炭素の供給が減少したため,炭素の固定が制限された.

結論:

CO2の供給量の減少は,ストロマトライトの減少に寄与した可能性がある.
大気中のCO2レベルの変化は,初期の生物学的炭素固定と微生物の生態系に大きな影響を与えた.

キーワード:

NASA Center ARCは,NASAセンターのARCとして運営されています.NASAの規律エキゾバイオロジー NASAの規範番号52−50は,NASAの規律番号52−50は,NASAの規律番号52−50は,NASAの規律番号52−50は,NASAの規律番号52−50は,NASAの規律番号52−50は,NASAの規律番号52−50は,NASAの規律番号52−50は,NASAの規律番号52−50は,NASAの規律番号52−50は,NASAの規律番号52−50は,NASAの規律番号52−50は,NASAの規律番号52−50は,NASA エクゾバイオロジープログラム

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