パレオセノ・エオセノ境界における急速な地球温暖化の影響が,新熱帯植生に及ぼす影響
Carlos Jaramillo1, Diana Ochoa, Lineth Contreras
1Smithsonian Tropical Research Institute, Box 0843-03092, Balboa, Ancon, Republic of Panama. jaramilloc@si.edu
まとめ
熱帯雨林は,気温上昇3°C〜5°Cにもかかわらず,旧生代・新生代熱最大期 (PETM) で繁栄した. 新しい植物種が現れ,温暖化と高CO2レベルに対する回復力を示した.
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
- パレオボタニーは古植物学です.
- ネオトロピカルエコロジーとは
背景:
- パレオセーヌ・エオセーヌ熱極 (PETM) は,熱帯の気温が3°5°C上昇し,急速な地球温暖化を引き起こした.
- 極端な温暖化現象に対する熱帯生態系の反応を理解することは,将来の気候影響の予測に不可欠です.
研究 の 目的:
- 熱帯雨林がPETM期間中に急速な温暖化にどのように反応するかを調査する.
- ネオトロピカル熱帯雨林における植物多様性と発生率の変化を評価する.
主な方法:
- コロンビア東部とベネズエラの西部の3つの層図学断面からのパリノロジック記録の分析.
- PETMにおける植物多様性および発生率の評価.
主要な成果:
- 植物多様性および起源率の有意な増加が観察されました.
- 新しいアンジオスペルム属が植物群に追加され,急速な適応と多様化を示した.
- 北部のネオトロピクスでは,干ばつの増加の証拠は見つかりませんでした.
結論:
- 熱帯雨林は,著しい温暖化と高いCO2レベルにもかかわらず,PETMの間に持続し,多様化しました.
- いくつかの仮説に反して,熱帯の生態系は熱ストレスによる深刻な妥協ではなく,回復力を示した.
- この研究は,過去の気候変動イベントに対する熱帯植物の適応能力を強調しています.
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