熱帯雨林とサバンナのグローバルな回復力 危機的な移行への回復力
Marina Hirota1, Milena Holmgren, Egbert H Van Nes
1Department of Aquatic Ecology and Water Quality Management, Wageningen University, Wageningen, Netherlands.
Science (New York, N.Y.)
|October 15, 2011
まとめ
熱帯雨林とサバンナは,移行に影響を与える重要な臨界点を持つ代替的な安定した状態として存在することがあります. この研究は,3つの異なる植生状態と,気候変動に対するそれらの回復力の証拠を提供します.
科学分野:
- エコロジー エコロジー エコロジー
- 気候科学 気候科学
- バイオジオグラフィー バイオジオグラフィー
背景:
- 熱帯雨林とサバンナの生態系は,代替的な安定した状態であると仮定されています.
- これらの生態系における重要な移行や臨界点に関する証拠は限られている.
- 現在の気候モデルでは,突然のシフトではなく,徐々に植生が反応することを想定しています.
研究 の 目的:
- 熱帯植生のための代替的な安定状態の存在を調査する.
- 臨界点を特定し,異なる植生状態の回復力を理解するために.
- 次世代の気候モデルの開発に役立つ.
主な方法:
- アフリカ,オーストラリア,南米における樹木覆いの分布データを分析した.
- 植生状態を惹きつける盆地の経験的再構築.
- 降雨パターンに関連した状態の回復力の評価.
主要な成果:
- 森林,サバンナ,樹木のない州という3つの異なる植生を惹きつける強力な証拠が見つかりました.
- これらの状態の回復力は,降水量に応じて普遍的に変化します.
- 植生状態の切り替えに敏感な地域を特定する.
結論:
- この研究は,熱帯地域の独特で安定した植生状態の存在を確認しています.
- 降水量は,これらの州の回復力と潜在的な転換点を決定する重要な要因です.
- この発見により,突然の植生変化を考慮した新世代の気候モデルが必要になる.
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