ENSOの移行期間中のバイオスフィアの一次生産
M J Behrenfeld1, J T Randerson, C R McClain
1National Aeronautic and Space Administration, Goddard Space Flight Center, Greenbelt, MD 20771, USA. mjb@neptune.gsfc.nasa.gov
Science (New York, N.Y.)
|April 3, 2001
まとめ
世界的な海洋と陸上の植物生産性 (NPP) は,エルニーニョからラニーニャのシフトの間に比較されました. 海洋NPPは,特に熱帯では増加したが,陸上NPPは,ENSOの明確なグローバルな反応を示さなかった.
科学分野:
- 地球科学 地球科学 地球科学
- 海洋学 海洋学とは
- エコロジー エコロジー エコロジー
背景:
- Sea-viewing Wide Field-of-View Sensor (SeaWiFS) は,海洋の植物プランクトンと陸上の植物の光吸収に関する重要なグローバルなデータを提供しています.
- 海と陸の両方の生態系の純一次生産 (NPP) を理解することは,気候モデリングと生態学的研究にとって不可欠です.
研究 の 目的:
- 大規模なエルニーニョからラニーニャへの移行に海と陸の生態系が同時に反応する純一次生産 (NPP) を比較する.
- エルニーニョ・サザン・オシレーション (ENSO) が地球と地域生物圏の生産性に与える影響を分析する.
主な方法:
- SeaWiFSによる植物プランクトンのクロロフィールバイオマスと陸上の植物の光採集の月間測定を活用した.
- ENSOイベントを含む,1997年9月から2000年8月の間の生物圏のNPP変動を分析した.
主要な成果:
- バイオスフィアの原子力発電所は,年間6ペタグラムの炭素によって変動し,年間111〜117Pg C−1.1の範囲でした.
- 海洋原子力発電所は,特にENSOによる上流と栄養素の利用可能性の変化の影響を受けた熱帯地域で,著しい増加を示した.
- グローバル・ランド・NPPは,ENSOの対応が一貫していないが,地域的に大きな差異が見られた.
結論:
- この研究は,ENSOイベントに対する海洋と陸の原子力発電所の異なる反応を強調しています.
- 熱帯海は,ENSOの生産性への影響に対して,地球上の陸上生物圏よりも敏感である.
- SeaWiFSのデータは,大規模な環境変化と,その影響が初次生産に及ぼす影響を追跡するのに非常に重要です.
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