珊瑚礁のpHの変化は,工業化以前の時代から現代の10年間の間,変化しています
Carles Pelejero1, Eva Calvo, Malcolm T McCulloch
1Research School of Earth Sciences, Australian National University, Canberra, ACT 0200, Australia. pelejero@cmima.csic.es
まとめ
二酸化炭素の吸収によって引き起こされる海洋酸化は,海洋生物にリスクをもたらす. 気候パターンに関連した自然のpH周期は,珊瑚礁がこれらの変化にどのように適応するかに影響を与える可能性があります.
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 海洋学
- 気候科学 気候科学
背景:
- 海は大気中の二酸化炭素を吸収し,酸性の上昇につながります.
- 海洋酸化が海洋生態系,特にサンゴ礁に与える影響は依然として不明である.
- 自然の海水のpHの変動を理解することは,種の適応性を評価するために極めて重要です.
研究 の 目的:
- リーフ水のpHの自然な変動性を決定する.
- 自然のpHサイクルと気候の振動との関係を調査する.
主な方法:
- 300年前の巨大なポライトスサンゴのボロン同位体組成の分析.
- 過去の海水のpH変動の再構築.
主要な成果:
- およそ50年周期で pH の有意な変動が観察されました.
- これらのpH周期は,海洋-大気異常の10年間の太平洋振動 (IPO) と相関しています.
- 自然のpHの変動は,海洋酸化の影響を大幅に調節することができます.
結論:
- 珊瑚礁の生態系は,気候パターンの影響を受けた自然的なpH変動を経験します.
- これらの自然循環は,海洋酸性化の進行に対するサンゴ礁の回復力を理解するために重要です.
- 海洋環境への自然変動と人為的な影響の相互作用を完全に理解するためには,さらなる研究が必要である.
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