高CO2の世界における植物プランクトンの化.
M Debora Iglesias-Rodriguez1, Paul R Halloran, Rosalind E M Rickaby
1National Oceanography Centre, Southampton, University of Southampton Waterfront Campus, European Way, Southampton SO14 3ZH, UK.
Science (New York, N.Y.)
|April 19, 2008
まとめ
二酸化炭素のレベルが上昇すると,海洋カルシウム炭酸酸塩の主要な生産者であるココリトホルスのカルシ化が予期せぬ形で加速する. この発見は,海洋酸化がこれらの重要な生物に与える影響に関する仮定に異議を唱える.
科学分野:
- マリン・バイオロジー マリン・バイオロジー
- 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:
- 大気中のCO2の増加によって引き起こされる海洋酸化は,一般的に海洋の化を抑制すると予測されています.
- コッコロリトフォアは,海洋カルシウム炭酸 (CaCO3) の生産に大きく貢献しており,世界の総生産量の約3分の1を占めています.
- 変化する海洋化学に対するココロリトフォアの反応を理解することは,将来の海洋動態を予測するために不可欠です.
研究 の 目的:
- エミリアニアのカルシフィケーションと一次生産に対する高 CO2 偏圧の影響を調査する huxleyi.
- 野外観測が,CO2の上昇に対するココリソフォアの反応に関する実験室での発見と一致するかどうかを評価する.
主な方法:
- エミリアニア・フクスレイイをCO2の偏圧の変動にさらした実験室での実験.
- 過去220年間におけるココリットの歴史的な質量変化を再構築するために,深海の沈殿物核の分析.
主要な成果:
- 実験室の結果は,高CO2条件下では,エミリアニア・フクセリイの石灰化と純一次生産の有意な増加を示した.
- 現地調査は,過去220年間にココロリトの平均質量が40%増加したことを示しており,これは実験室での発見と一致している.
- ココロリトフォアは,大気中のCO2濃度の上昇に積極的に反応しています.
結論:
- 予想に反して,Emiliania huxleyiは,CO2の上昇とともに,強化された化を示しています.
- ココロリト群の観測された歴史的増加は,ココロリトホルスが変化する海洋条件に適応しているという結論を支持しています.
- これらの発見は,将来の海洋と気候のシナリオを予測するバイオジオケミカルモデルの見直しを必要としています.
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