スケール効果と人間の影響が,高さ上の種豊かさのグラデーションに及ぼす影響
D Nogués-Bravo1, M B Araújo, T Romdal
1Department of Biodiversity and Evolutionary Biology, National Museum of Natural Sciences, CSIC, C/ José Gutiérrez Abascal, 2, 28006 Madrid, Spain. davidnogues@mncn.csic.es
Nature
|May 10, 2008
まとめ
種多様性のパターンは,分析の規模に依存する. 研究の規模を変化させると,矛盾するパターンが生まれ,普遍的な生物多様性グラデーションの探求が妨げられる.
科学分野:
- エコロジー エコロジー エコロジー
- 生物多様性 科学 科学 生物多様性
- バイオジオグラフィー バイオジオグラフィー
背景:
- 環境の梯度,特に標高は,種の豊かさのパターンを理解するために不可欠です.
- 以前の研究は普遍的なパターンを想定していたが,コンセンサスは依然として難解である.
- 高度グラデーションは,多様性仮説を検証するための重要なモデルである.
研究 の 目的:
- 分析のスケールが,標高グラデーションに沿って観察された種豊かさのパターンにどのように影響するか調査する.
- スケール効果が文献で報告されている矛盾する多様性パターンを説明できるかどうかを判断する.
- 異なる多様性仮説を支持するスケールの影響を評価する.
主な方法:
- ピレニアの花のグラデーションから大規模なデータセット (400,000の記録,3,046種の) を再サンプリングする.
- 粒子のサイズとグラデントの範囲を調整することによって,種豊かさのパターンを様々なスケールで分析します.
- 規模に依存するパターンに基づいて,競合する多様性仮説の支持を統計的に評価する.
主要な成果:
- 種多様性のパターンは,分析の規模が縮小するにつれて,うんざり形から単調に変化した.
- スケール効果だけで,文献で以前に報告された矛盾するパターンを生み出した.
- スケール効果は,さまざまな多様性仮説の統計的支持に大きく影響した.
結論:
- 観察された種の豊かさのパターンは,高度にスケールに依存しています.
- スケール効果は,以前の研究における不一致を説明し,普遍的な多様性グラデーションの識別を妨げることができます.
- 山岳生態系に対する人間の影響は,スケール効果を悪化させ,生物多様性研究を複雑にする可能性があります.
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