チリ沿岸沖の酸素不足地帯の水域における神秘的な硫黄循環
Don E Canfield1, Frank J Stewart, Bo Thamdrup
1Institute of Biology and Nordic Center for Earth Evolution, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark. dec@biology.sdu.dk
Science (New York, N.Y.)
|November 13, 2010
まとめ
海洋の酸素最小のゾーンは窒素循環によって支配されていますが,この研究は重要な神秘的な硫黄循環を明らかにしています. 硫酸塩の還元と硫化物の酸化は,これらの酸素のない環境におけるエネルギーと元素の循環の鍵です.
科学分野:
- 海洋生物ジオケミストリー
- 微生物生態学とは
- 海洋学 海洋学とは
背景:
- 窒素循環は,伝統的に,海洋酸素最小限ゾーン (OMZs) の研究を支配しています.
- OMZにおける微生物のプロセスは,地球的な元素の循環にとって極めて重要です.
- OMZを理解することは,気候変動に対する海洋の反応を予測する鍵です.
研究 の 目的:
- 酸素不足地帯における硫黄循環の役割を調査する.
- 硫酸塩還元と硫化物の酸化が,OMZにおけるエネルギーフックスの貢献度を測定する.
- 海洋環境における硫黄と窒素の循環の関連性を調査する.
主な方法:
- 微生物のコミュニティを分析するために分子技術を用いた.
- バイオジオケミカルフロースを定量化するためにプロセスの速度測定を使用しました.
- チリ北部沖の酸素のない海域を研究した.
主要な成果:
- 硫酸塩の還元と硫化物の酸化は,OMZにおけるエネルギー流と元素の循環に大きく貢献する.
- 生成された硫化物が即座に再酸化される神秘的な硫黄循環が特定されました.
- この硫黄循環は,アナモックスやその他の窒素循環プロセスと密接に関連しています.
結論:
- 硫黄循環は,これまで認識されていたよりも,OMZの生地化学においてより重要な役割を果たしています.
- 謎めいた硫黄の循環は,OMZにおける全体的な生地化学的循環に影響を与えます.
- これらの発見は,地球規模の海洋生物地球化学に対するより広範な影響を示唆しています.
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