南太平洋を横断する水熱溶解金属の盆地規模の輸送
Joseph A Resing1, Peter N Sedwick2, Christopher R German3
1Joint Institute for the Study of the Atmosphere and the Ocean, University of Washington and NOAA-PMEL, 7600 Sand Point Way NE, Seattle, Washington 98115, USA.
Nature
|July 10, 2015
まとめ
熱水噴出孔は溶けた鉄を海に放出し,その輸送の制限に関する以前の仮定に異議を唱える. この研究は,開口からの鉄の長距離輸送が海洋生物地球化学に大きな影響を与え,南大洋の初次生産をサポートすることを示しています.
科学分野:
- 海洋化学 海洋化学について
- 海洋学 海洋学 海洋学
- バイオジオケミストリー バイオジオケミストリー
背景:
- 熱水噴出孔は海洋化学の重要な調節体であり,微量元素の濃度に影響を与えます.
- 鉄は,海洋原発生産と世界の炭素循環にとって重要な栄養素です.
- 以前は,水熱溶解鉄は,風口の近くの溶液から急速に失われると考えられていた.
研究 の 目的:
- 熱水噴出孔から溶けた鉄の長距離海洋輸送を調査する.
- 海洋生物地球化学における水熱鉄の投入の重要性を再評価する.
- 液熱溶解鉄の地球的な流れを定量化するために.
主な方法:
- 米国GEOTRACES東太平洋ゾナルトランセクト (EPZT) のデータを活用した.
- 南太平洋で溶けた鉄,マンガン,アルミニウムの濃度を分析した.
- シミュレーションのために世界規模の海洋生物地球化学モデルを使用した.
主要な成果:
- 南太平洋で水熱溶解鉄,マンガネス,アルミニウムの大幅な横横輸送が実証された.
- 熱水噴出で溶解した鉄のほぼ保守的な行動が観察され,長寿が延長されたことを示しています.
- 推定の世界的な水熱溶解鉄の輸入量は,年間3〜4ギガモールで,以前の推定値の4倍である.
結論:
- 水熱溶解鉄は,以前の考えに反して,長い海洋距離を移動することができます.
- 物理化学的安定化は,この長距離輸送に極めて重要です.
- 水熱による鉄は,南洋の輸出生産を維持する上で重要な役割を果たしています.
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