体制転換の早期警告:生態系全体の実験
S R Carpenter1, J J Cole, M L Pace
1Center for Limnology, University of Wisconsin, Madison, WI 53706, USA. srcarpen@wisc.edu
Science (New York, N.Y.)
|April 30, 2011
まとめ
回復の鈍化や多様性の増加などの統計的早期警告信号は,主要な生態学的変化を予測することができます. この研究は,湖の中のこれらの信号を確認した.
科学分野:
- エコロジー エコロジー エコロジー
- エコロジカル・ダイナミクス
- 生態系管理とは,生態系管理のことです.
背景:
- エコロジムのシフトは,生態系の状態の急激で重大な変化を表します.
- 変動率の上昇や回復率の低下などの早期警告信号 (EWS) は,これらのシフトに先行すると理論化されています.
- 生態系全体におけるEWSの実証的検証は依然として限られている.
研究 の 目的:
- 統計的な早期警告信号が,水生食物網における実験的に誘発されたレジームシフトに先行するという仮説を検証する.
- 理論的なEWSの実世界,全体的なエコシステム文脈での適用性を評価する.
主な方法:
- 水中の食物網は,頂点の肉食動物の数を徐々に増加させることで,3年間にわたって実験的に不安定化されました.
- 近くの湖は,比較分析のための基準生態系として機能した.
- 2つの湖では,リターン率とバリエーションを含む統計指標が監視されました.
主要な成果:
- 操作された湖は,差し迫った政権交代の明白な早期警告信号を示した.
- 食物網の動態の変化などのこれらのシグナルは,シフトが完了する1年以上前に現れた.
- 基準湖は同様の統計的傾向を示せず,実験効果を強調した.
結論:
- この研究は,生態系体制の変化を予測するために,統計的早期警告信号の使用に対する強力な経験的支持を提供します.
- 発見は理論的予測を裏付け,生態系の監視と管理のための実用的な応用を示唆しています.
- 体制の変化を早期に検出することで,生態系の崩壊を防ぐための適切な介入が可能になる可能性があります.
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