現実的な種の損失は,生物的侵略者に対する草原の抵抗性を不釣り合いに減少させる
Erika S Zavaleta1, Kristin B Hulvey
1Environmental Studies Department, University of California, Santa Cruz, CA 95064, USA. zavaleta@ucsc.edu
Science (New York, N.Y.)
|November 13, 2004
まとめ
現実的な種の消失は,草原の侵入に対する耐性を劇的に低下させ,特に植物機能群全体が消滅したときです. これは,生態系の機能に対する生物多様性の減少における種の順序の重要性を強調しています.
科学分野:
- エコロジー エコロジー エコロジー
- 環境科学 環境科学
背景:
- 生物多様性の減少は,生態系の機能に影響を及ぼします.
- 以前の研究では,種滅亡のシーケンスがしばしば見過ごされている.
- 種の機能的役割は,生物多様性-生態系機能の関係において極めて重要です.
研究 の 目的:
- 実験的に,現実的な種の減少が草原の侵襲に対する耐性をどのように影響するかをテストする.
- 生態系プロセスに対する種順序と機能群の喪失の影響を調査する.
主な方法:
- 草原の多様性における観察された変動を利用して実験を設計した.
- 植物全体の機能群の消失を含む,現実的な種の消失シナリオをシミュレートした.
- 種を除去後の侵入抵抗性の評価された変化.
主要な成果:
- 侵襲に対する耐性は,種が徐々に消滅するにつれて劇的に減少しました.
- 植物全体の機能群は,予想よりも速いペースで消滅した.
- 現実的でランダムでない種の損失は,ランダムな損失よりも大きな影響を及ぼしました.
結論:
- 種の消失の順序は,侵略に対する耐性などの生態系プロセスに大きな影響を及ぼします.
- 希少種の消失でさえ,重大な結果をもたらす可能性があります.
- 生物多様性の減少は,ランダムでない場合,先ほどランダム化実験によって示されたよりも,生態系の安定に対するより大きな脅威です.
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