鍵となる草食動物における集団サイクルがヨーロッパ全域で鈍化している
Thomas Cornulier1, Nigel G Yoccoz, Vincent Bretagnolle
1School of Biological Sciences, University of Aberdeen, Zoology Building, Tillydrone Avenue, Aberdeen AB24 2TZ, UK. cornulier@abdn.ac.uk
Science (New York, N.Y.)
|April 6, 2013
まとめ
小規模な草食動物集団は,鳥類のように,冬の成長が減少したため,人口サイクルが鈍化しており,気候変動が生態系機能に影響することを示唆しています. これらの変化は,ヨーロッパ全域の食物網に影響を及ぼす可能性があります.
科学分野:
- エコロジー エコロジー エコロジー
- 人口のダイナミクス
- 気候変動の影響 気候変動の影響
背景:
- 1980年代以降,小規模な草食動物サイクルの崩壊に関する懸念が存在しています.
- 潜在的な原因には,外的な環境変化や内的なストキャスティシティが含まれます.
- これらのサイクルを失うと,生態系の重要な機能が脅かされます.
研究 の 目的:
- 小規模な草食動物サイクルの抑制の一般性を調査する.
- 環境の変化や内在的な要因がこれらの現象を誘発しているかどうかを判断する.
- 根本的な原因を特定し,将来の傾向を予測する.
主な方法:
- 飛鳥の豊富さに関するタイムシリーズデータの大規模なコンパイルの分析.
- 人口増加率の評価,特に冬季.
- 循環性に関与する規制プロセスの検討.
主要な成果:
- ボールサイクル振幅の一貫した鈍化が観察されました.
- 冬季の人口増加の減少は,この減退と強く関連しています.
- 循環性を推進する規制プロセスは,無傷のままです.
- ヨーロッパ全域の広範囲にわたる変化と鳥類によって,共通の気候の要因が示唆されている.
結論:
- 小規模な草食動物集団は,冬季の人口増加の減少に関連して,サイクル幅の減少を示しています.
- 観測された変化は,欧州の生態系に影響を与える共通の気候ドライバーを示唆しています.
- 将来の予測は,低振幅の変動がより長い期間続くことを示し,トロフィック・ウェブに潜在的に影響を与える可能性がある.
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