値とカリブ海のサンゴ礁の回復力
Peter J Mumby1, Alan Hastings, Helen J Edwards
1Marine Spatial Ecology Lab, School of BioSciences, University of Exeter, Prince of Wales Road, Exeter EX4 4PS, UK. p.j.mumby@ex.ac.uk
Nature
|November 2, 2007
まとめ
カリブ海のサンゴ礁は,1983年のの絶滅後,藻類が優勢である状態に閉じ込められているかもしれない. 牧草地とサンゴの覆面が臨界値を下回ると回復力が失われ,不可逆的な生態系の変化が起こる危険性があります.
科学分野:
- 海洋生態学 海洋生態学とは
- 生態系のダイナミクス
- 保護科学とは,自然保護に関する科学です.
背景:
- 珊瑚礁の健康は,世界的に,特にカリブ海で,1983年のDiadema antillarum urchinの絶滅などの要因により,悪化しています.
- マクロアルガの開花はサンゴ礁の健康状態が悪化していることを示しており,藻類の優位性へのこれらの変化の逆転可能性について疑問を投げかけています.
研究 の 目的:
- カリブ海のサンゴ礁が,マクロ藻類が支配する別の安定した状態に変化しているかどうかを判断する.
- 珊瑚礁の回復力を影響する,牧草と珊瑚の覆いの重要な値を特定する.
主な方法:
- 完全にパラメータ化されたシミュレーションモデルと単純な分析モデルを使用した.
- 牧草の動態とサンゴ礁の安定性に対する1983年のの死亡率の影響を分析した.
- エコシステムの回復力を評価するために,サンゴの覆面と草食性の重要な値を定義します.
主要な成果:
- 1983年のの絶滅により,カリブ海のサンゴ礁は他の安定した状態に敏感になり,主に魚への放牧圧力を移した.
- 有意なヒステレスが示され,藻類の優位性からの回復は,重要な値を超えると困難であることが示されています.
- ほとんどの放牧の値が現在の魚のレベルに近いことが判明し,魚の過剰搾取に対するサンゴ礁の感受性を強調した.
結論:
- カリブ海のサンゴ礁はヒステレシスを示し,生態学的混乱後のマクロ藻類の持続的な優位性に対して脆弱になります.
- 珊瑚礁の回復力を回復し,相変化を防ぐために,牧草地と珊瑚の kritical thresholds を特定する必要があります.
- この研究は,サンゴ礁の回復のための目標を提供し,管理者がグローバルな混乱を局所レベルで対処するのに役立ちます.
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