海洋硫酸塩の減少の世界的な割合と,海底の代謝活動への影響
Marshall W Bowles1, José M Mogollón2, Sabine Kasten3
1MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany. bowlesmw@uni-bremen.de.
Science (New York, N.Y.)
|May 10, 2014
まとめ
海洋堆積物における世界的な硫酸塩減少率は,人工ニューラルネットワークを使用して今より良く定量化されています. この重要なプロセスは,有機炭素の重要な酸化を説明し,海底の下には独特の微生物の生息地があることを明らかにします.
科学分野:
- 地質化学 地質化学
- マリン・バイオロジー マリン・バイオロジー
- 計算科学 計算科学とは
背景:
- 硫酸塩還元は,海洋堆積物における重要な酸化還元プロセスである.
- 硫酸塩の減少の世界的な割合は十分に理解されていません.
- このプロセスは,海洋生物地球化学のサイクルにおいて重要な役割を果たします.
研究 の 目的:
- 世界の硫酸塩削減率を定量化するために.
- 海洋堆積物における硫酸塩還元率の分布を推定する.
- 海底の微生物生命に及ぼす影響を理解する.
主な方法:
- 人工ニューラルネットワークモデルを開発した.
- モデルを199の硫酸塩プロファイルで訓練した.
- モデルをジオモルフォロジカル,ジオケミカルマップで制限した.
主要な成果:
- 年間11.3テラモールで推定の世界的な硫酸塩の減少,以前の推定値の ~15%.
- 硫酸塩の減少は,海底への有機炭素の流れの12~29%を占めています.
- 大陸の縁のプロカリオット生息地と,深淵の平原との対比が明らかになった.
結論:
- 海底の微生物生物の分布は,硫酸塩の減少によって強く影響されています.
- 大陸の縁では,硫酸塩が少ない地域では細胞数がより多いことが示されています.
- アビッサル平原は,酸素および/または硫酸塩を減少させる堆積物でほとんどの生命を保ちます.
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