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植物プランクトンの最適な窒素からリンへのステキオメトリー
Christopher A Klausmeier1, Elena Litchman, Tanguy Daufresne
1Department of Ecology and Evolutionary Biology, Princeton University, Princeton, New Jersey 08544, USA. christopher.klausmeier@biology.gatech.edu
Nature
|May 14, 2004
まとめ
植物プランクトンの窒素とリン (N:P) の比率は,レッドフィールド比率とは異なり,固定されていません. 生態学的条件が最適な植物プランクトンN:Pを決定し,8.2から45.0まで変化します.
科学分野:
- 海洋生物学 海洋生物学
- バイオジオケミストリー バイオジオケミストリー
- 植物プランクトン生理学 植物プランクトン生理学
背景:
- レッドフィールド比 (N:P = 16) は,プランクトンと海洋水の平均窒素/リン比を表しています.
- 植物プランクトンは,窒素固定を通じて,海洋のN:P比を調整して,その要求を満たす可能性があると推測されています.
研究 の 目的:
- 生理学的モデルを使用して,最初の原則から最適な植物プランクトンステキオメトリを導き出す.
- 生態学的条件が植物プランクトンの窒素からリンへの要求にどのように影響するか調査する.
主な方法:
- 植物プランクトンの生理学のステキオメトリックに明示的なモデルの開発.
- 様々な生態学的シナリオ (例えば,栄養素の制限,成長モード) の下で資源競争のシミュレーション.
主要な成果:
- 競争の均衡は,より高いN:P比 (より多くのPに乏しい機械) を好む.
- 指数関数的な成長は,より低いN:P比 (よりP豊富な機械) を好む.
- 最適なN:P比は,環境条件によって大きく異なる (8.245.0).
結論:
- 定規のレッドフィールドのN:P比は,普遍的な生化学的最適ではない.
- 植物プランクトンN:Pステキオメトリーは,種別であり,環境に依存しています.
- 生化学的な制約だけでなく,生態学的要因が,最適な植物プランクトンのN:P比を決定する.
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