植物の多様性は,地球規模での負の密度依存の強さとともに増加する
Joseph A LaManna1,2, Scott A Mangan2, Alfonso Alonso3
1Tyson Research Center, Washington University in St. Louis, St. Louis, MO, USA. joe.a.lamanna@gmail.com.
Science (New York, N.Y.)
|July 1, 2017
まとめ
熱帯林は,希少種に対するより強い同種の負の密度依存 (CNDD) により,より高い生物多様性を維持しています. この相互作用パターンは 希少種が存続するのを助け 温帯に比べて 希少種の数が多いことを説明します
科学分野:
- エコロジー
- 生物多様性科学
- 森林の生態学
背景:
- 生物多様性のパターンは生物の相互作用によって影響を受けます
- 同種の負密度依存 (CNDD) は,特に熱帯では,種の多様性を維持するために提案された重要なメカニズムです.
- 異なる緯度におけるCNDDの役割を理解することは,地球規模の生物多様性グラデーションを説明するために極めて重要です.
研究 の 目的:
- 同種の負密度依存 (CNDD) と緯度間の関係を調査する.
- 熱帯と温帯の森林の種数パターンに CNDD がどのように影響を与えるかを決定する.
- 熱帯で強いCNDDが 樹種の多様性を高めるという仮説を検証する.
主な方法:
- 全世界の24の森林から得られたデータで 3千種類以上の樹木と 約240万本の樹木が含まれています
- 熱帯と温帯にわたるCNDDのパターンを分析した.
- 異なる緯度におけるCNDDの強度と種の豊富さの関係を調べた.
主要な成果:
- 世界の木種の多様性のパターンは,熱帯と温帯の緯度でより強いCNDDと関連しています.
- CNDDと種の豊富さの関係における重要な緯度変化が観察されました.
- CNDDは 温帯地域と比較して 熱帯の希少種に強く見られた.
結論:
- 熱帯雨林では,特に希少種の場合,より強いCNDDは,より高い木種の多様性を維持するのに寄与します.
- 熱帯林と温帯林のコミュニティの間には,局所的な生物学的相互作用の根本的な違いがあります.
- この発見は,熱帯生物多様性の説明において,専門的な相互作用とCNDDの役割を支持しています.
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