肉食動物密度のスケーリングのための共通のルール
Chris Carbone1, John L Gittleman
1Institute of Zoology, Zoological Society of London, Regent's Park, London NW1 4RY, UK. chris.carbone@ioz.ac.uk
Science (New York, N.Y.)
|March 23, 2002
まとめ
資源の可用性は肉食動物集団の密度を決定するのであり,体の大きさではない. 一般的なモデルは,獲物のバイオマスが肉食動物のバイオマスを決定し,絶滅危惧種の肉食動物の保全活動を支援することを明らかにしています.
科学分野:
- エコロジー エコロジー エコロジー
- 動物学 動物学
- 保護生物学の保護生物学
背景:
- 人口密度は,エネルギー需要のため,体量に比例すると理論化されています.
- 資源の利用可能性は,人口密度に影響を与える重要な要因であり,潜在的にスケーリングパターンを変化させる可能性があります.
研究 の 目的:
- 肉食動物 (食肉類類類) の集団密度の変動に関する一般的なモデルを開発し,テストする.
- 獲物のバイオマス,肉食動物の体量,および人口密度の間の関係を調査する.
主な方法:
- カーニボラ族の集団密度の一般的なモデルを開発した.
- 肉食動物の数と獲物のバイオマスの比率を分析した.
- 獲物の生産性の質量特有の方程式を用いた.
主要な成果:
- 約1万キログラムの獲物のバイオマスは,肉食動物の体量とは関係なく,肉食動物のバイオマスの90キログラムを支えている.
- 肉食動物の数と獲物のバイオマスの比率は,肉食動物の質量と逆方向に比例する.
- 獲物の生産性単位あたりの肉食動物数は,−0.75.5に近い指数を持つ肉食動物質量に比例する.
結論:
- 派生したスケーリングルールは,幅広い肉食動物種 (大きさの3桁以上) の集団密度を正確に予測します.
- この関係は,危険にさらされている肉食動物種を特定し,保全行動の優先順位を決めるための枠組みを提供します.
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