微生物のオートロフィー:海洋堆積物における有機炭素の主要な源である
まとめ
海の泥のバクテリアは二酸化炭素を固定し,有機炭素を生成します. このプロセスは硫黄細菌によって推進され,硫化物豊富な環境において不可欠であり,有機物質と細菌の集団の増加に関連しています.
科学分野:
- マリン・マイクロバイオロジー
- バイオジオケミストリー バイオジオケミストリー
- 地化学のサイクルとは
背景:
- 硫化物豊富な海洋沈殿物は,ユニークな微生物群を宿している.
- 海洋の泥の有機炭素は,微生物のプロセスを含む様々な源から発生します.
- 化学オートロフィーは,太陽光が欠けている環境では,炭素の固定に役割を果たします.
研究 の 目的:
- 海洋の泥の有機炭素生産における化学的オートトロフ的二酸化炭素固定の役割を調査する.
- この環境における炭素固定に責任を負う特定の微生物群を特定する.
- 炭素固定速度と地化学的および微生物学的パラメータを相関させるため.
主な方法:
- 堆積物の中核における二酸化炭素固定速度の測定.
- 有機炭素含量と炭素と窒素の比率の分析.
- バクテリアの細胞数と支配的な微生物群の特定.
- 硫酸硫酸塩を用いた濃縮実験と酸素濃度の操作.
主要な成果:
- 二酸化炭素の固定のピークは,底下40cmで観察されました.
- この固定ピークは,有機炭素,C:N比率,細菌細胞数の増加と相関していた.
- 硫酸チオスは炭素固定を刺激し,無酸素状態はそれを阻害した.
結論:
- 細菌による化学的オートトロフ的二酸化炭素固定は,硫化物豊富な海洋泥の有機炭素の重要な源である.
- 化学的自己栄養硫黄細菌は,この固定に責任を負う主要な生産者である.
- この発見は,深海の堆積物における微生物の炭素循環の生態学的重要性を強調しています.
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