南アマゾンの熱帯雨林の千年規模の動態
F E Mayle1, R Burbridge, T J Killeen
1Department of Geography, University of Leicester, Leicester LE1 7RH, UK. fem1@leicester.ac.uk
まとめ
アマゾンの熱帯雨林は,気候変動によりボリビアの南に広がっています. この拡大は,熱帯間の収束地帯によって引き起こされた.
科学分野:
- 古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは
- エコロジー エコロジー エコロジー
- バイオジオグラフィー バイオジオグラフィー
背景:
- アマゾンの熱帯雨林とサバンナの境界線は,気候変動に敏感であり,種の形成に影響を与えます.
- これらの境界線の長期的な動態を理解することは極めて重要ですが,限られています.
研究 の 目的:
- アマゾンの熱帯雨林の境界の動態を数千年にわたって再構築する.
- 過去5万年におけるアマゾン熱帯雨林の最南端の範囲を決定する.
主な方法:
- アマゾニアの南の縁からの後期四次期の花粉記録の分析.
- 過去の植生の変化と境界の変化の再構築.
主要な成果:
- ボリビア東部にある湿った常緑の熱帯雨林は,過去3000年にわたって南に広がっています.
- 現在の森林の境界線は,少なくとも5万年にわたって観察された最も南の範囲です.
- 熱帯雨林の拡大は,熱帯間の収束地帯の季節的緯度移動の増加と相関しています.
結論:
- 過去の気候変動,特にミランコビッチフォースが熱帯間の収束地帯に影響を与え,アマゾンの熱帯雨林の拡大を促した.
- これらの発見は,アマゾン流域の長期的な生態学と気候の歴史についての洞察を提供します.
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