大量絶滅の回復過程で生態系機能と回復力から切り離された多様性
Sarah A Alvarez1,2,3, Samantha J Gibbs4, Paul R Bown5
1School of Geographical Sciences, University of Bristol, Bristol, UK. sarah.alvarez@unigib.edu.gi.
Nature
|September 27, 2019
まとめ
シクスルブ衝突で 海洋生態系が崩壊した 衝突後の海洋社会は 安定するのに180万年かかり 炭素循環と生物学的ポンプの効率を回復し 機能が種の豊かさより優先されました
科学分野:
- 古代海洋学
- 海洋生態学
- 生地化学
背景:
- 6600万年前のチクスルーブ・ボリドの衝突で 大量絶滅が起こり 海の生態系が崩壊し 地球の生地化学的サイクルが 破壊されました
- 衝撃後の海洋生態系の回復と生地化学機能の回復の時間スケールとメカニズムの理解は,詳細な生物学的データの欠如によって制限されています.
研究 の 目的:
- 海洋生態系と生地化学的機能のChicxulub後の影響回復を調査する.
- 生態系の変動や 安定した 回復力のあるコミュニティの出現の時間軸を 決定する
- 海洋の炭素循環と生物学的ポンプ機能の回復を結びつける
主な方法:
- 衝突後の1300万年のナノプランクトンの タイムシリーズの分析
- コミュニティ構造,細胞サイズスペクトル,そして生地化学循環の指標の検討.
- 生物学的データと炭素循環回復と生物学的ポンプ機能の関連性
主要な成果:
- 衝突後の海域は 180万年の間 大きく変動しました
- 安定した,弾力的なバランス状態のコミュニティが生まれました 細胞の大きさの幅広いスペクトルが特徴です
- この安定したコミュニティへの移行は 炭素循環の回復と 完全に機能する生物学的ポンプと一致しました
- コミュニティの安定と生物学的ポンプの効率が回復したにもかかわらず,種の豊かさは低いままでした.
結論:
- 生態系の回復と生地化学の循環は 長期にわたって 根本的に結びついています
- 生物の多様性だけでなく 生態学的機能も コミュニティの回復力や海洋の健康を 左右する要因です
- この研究は,衝撃後の回復の見積もりを洗練し,完全な分類学的な豊かさの回復よりもはるかに短い機能的な回復を示しています.
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