生態系の性質と森林の減少は,対照的な長期の時間順序を構成しています
David A Wardle1, Lawrence R Walker, Richard D Bardgett
1Department of Forest Vegetation Ecology, Swedish University of Agricultural Sciences, SE901 83 Umeå, Sweden. david.wardle@svek.slu.se
Science (New York, N.Y.)
|June 19, 2004
まとめ
森林の生態系は,長期にわたり,混乱することなく衰えていく. この減少には,木のサイズが縮小され,の制限が増加し,世界の森林種間の分解と微生物の活動に影響を与えています.
科学分野:
- エコロジー エコロジー エコロジー
- 森林科学 林業科学 林業科学
- エコシステムのダイナミクス
背景:
- 生態系の発展は,継承として知られており,通常,バイオマスの増加につながります.
- しかし,長期的な生態系の安定性は,干渉の欠如によって脅かされ,潜在的に衰退期につながる可能性があります.
研究 の 目的:
- 長期的な森林継承における生態系衰退の特徴と流行を調査する.
- 多様な地球規模の森林生態系における衰退段階に関連した重要な生態学的指標を特定する.
主な方法:
- 熱帯,温帯,北陸の森林地帯 (オーストラリア,スウェーデン,アラスカ,ハワイ,ニュージーランド) の6つの長期クロノシーケンスの分析.
- 木の基礎面積,基板の窒素とリンの比,ゴミの分解率,リン放出,分解剤の微生物バイオマスと活性の測定.
主要な成果:
- 研究されたすべてのクロノシーケンスの衰退段階は,木の基礎面積の減少と関連していました.
- 亜基質の窒素とリンの比率の増加は,時間の経過とともに漸進的なリンの制限を示した.
- 廃棄物の分解,の放出,分解器の微生物の活動が減少した.
結論:
- 森林の継承過程で達成される最大バイオマスは,干渉なしに長期的には持続不可能である.
- フォスフォースの制限と分解の減少によって特徴づけられる生態系の衰退の予測可能なパターンは,世界中の森林で起こります.
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