草食動物は,アマゾンの森の樹木によって生息地の特化を促進します
Paul V A Fine1, Italo Mesones, Phyllis D Coley
1Department of Biology, University of Utah, 257 S. 1400 East, Salt Lake City, UT 84112, USA. fine@biology.utah.edu
Science (New York, N.Y.)
|August 3, 2004
まとめ
ペルーのアマゾンにおける生息地の専門化は,土壌タイプと相互作用する草食動物による圧力によって引き起こされる. 粘土の専門家は,より速く成長しますが,保護を必要としますが,白砂の専門家は,草食動物がいるときに,自分の土壌で繁栄します.
科学分野:
- エコロジー エコロジー エコロジー
- 植物生物学 植物生物学
- アマゾンの生態系
背景:
- ペルーのアマゾンの粘土と栄養が少ない白砂の土壌には,独特の植物群が住んでいます.
- 生息地の専門化は,説明を必要とする重要な生態学的現象である.
研究 の 目的:
- 植物の成長と反草食者の防御の間のトレードオフが,生息地の専門化を推進するかどうかを調査する.
- 専門化を強制する上で,土壌の種類と草食動物による圧力の役割を決定する.
主な方法:
- 6つの属から20種の樹木を相互移植した研究.
- 苗木は,粘土と白砂の両方の土壌で育てられました.
- 草食動物の存在が操作された.
主要な成果:
- 粘土の特殊種は,草食動物が存在しないとき,両方の土壌タイプで白砂の特殊種よりも速い成長を示した.
- 草食動物の存在下では,白砂の専門家が白砂の森を支配し,粘土の専門家が粘土の森を支配した.
- これは,草食動物への圧力と土壌の種類との間の重要な相互作用を示しています.
結論:
- このアマゾンのシステムにおける生息地の専門化は,土壌条件のみによるものではなく,草食と土壌タイプの相互作用によって著しく影響を受けています.
- 草食動物による圧力によって調節される成長と防衛のトレードオフは,土壌の種類によって異なる植物コミュニティの分布を強制する.
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