大気中の二酸化炭素の増加が珊瑚礁に及ぼす地化学的影響
1National Center for Atmospheric Research, Boulder, CO 80307, USA. Kansas Geological Survey, University of Kansas, Lawrence, KS 66047, USA. Department of Geophysical Sciences, University of Chicago, Chicago, IL 60637, USA. Observatoire Oceanolo.
まとめ
二酸化炭素濃度の上昇は,カルシフィケーションを減少させることで,サンゴ礁を脅かしている. これは,海洋酸性化がアラゴニット飽和度を低下させ,サンゴ礁の成長やその他の化生物を阻害するので,海洋生態系に影響を及ぼします.
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 海洋学とは
- バイオジオケミストリー バイオジオケミストリー
背景:
- 珊瑚礁は,カルシ化する生物によって作られた重要な海洋生態系です.
- サンゴ礁の形成は,炭酸カルシウム (CaCO3) の蓄積に依存しています.
- 石灰化の速度は環境条件,特に海洋化学に敏感です.
研究 の 目的:
- 増加した二酸化炭素がサンゴ礁の化に与える影響を評価する.
- アラゴニトの飽和状態と生物学的降水量の変化を予測する.
- 海洋の化生態系に対するより広範な生地化学的影響を理解する.
主な方法:
- 高濃度の二酸化炭素下での海洋表面水の化学分析.
- アラゴナイトの飽和状態のモデリング.
- 生物学的アラゴニトの降水率の推定.
主要な成果:
- 20世紀半ばまでに熱帯アラゴナイトの飽和度が30%減少すると予測されています.
- 生物学的アラゴニトの降水量が14-30%減少すると予想されています.
- メタステーブルなCaCO3.3の分泌によるサンゴ礁に対する脅威を特定した.
結論:
- 大気中の二酸化炭素の増加は,珊瑚礁の化を著しく損なう.
- 海洋酸化は,サンゴ礁の構造的整合性に深刻な脅威をもたらしています.
- 生地化学的な影響は,他の化海洋生物や生態系にも及ぶ.
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