大気中の窒素堆積によって引き起こされる湖のN:Pステキオメトリーと栄養素の制限の変化
James J Elser1, Tom Andersen, Jill S Baron
1School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA. j.elser@asu.edu
まとめ
大気中の窒素堆積は湖の栄養分比を変化させ,植物プランクトンの成長を窒素制限からリン制限にシフトさせます. これは,人間の活動が水生生態系に及ぼす広範な影響を強調しています.
科学分野:
- 環境科学 環境科学
- エコロジー エコロジー エコロジー
- リムテクノロジーとは
背景:
- 人間の活動により,世界の窒素 (N) 循環が著しく増加しています.
- 大気中の窒素 (N) の堆積は,生態系への人為的なNの輸入の主要な経路です.
研究 の 目的:
- 大気中の窒素 (N) の堆積が湖の栄養制限に与える影響を調査する.
- 変化した窒素 (N) とリン (P) の比率が植物プランクトンの成長にどのように影響するかを決定する.
主な方法:
- ノルウェー,スウェーデン,コロラド州の湖における窒素 (N) とリン (P) のステキオメトリック比率の分析.
- 生態学的栄養素制限パターンの変化の観察.
主要な成果:
- 大気中のN堆積は,研究された湖のN:P比を増加させた.
- 植物プランクトンの成長は,窒素 (N) 限度から,高濃度Nの堆積湖で,リン (P) 限度へと変化した.
結論:
- 人為的な窒素 (N) 濃縮は,湖の基本的な生態学的プロセスを変化させます.
- これらの変化は,遠隔の湖でさえも,生地化学的サイクル,トロフィクダイナミクス,生物多様性に影響を及ぼします.
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