川の生態系機能に対する栄養汚染の大陸規模の影響
Guy Woodward1, Mark O Gessner, Paul S Giller
1Department of Zoology, Ecology and Plant Science, University College Cork, National University of Ireland, Cork, Enterprise Centre, Distillery Fields, Cork, Ireland. g.woodward@qmul.ac.uk
Science (New York, N.Y.)
|June 16, 2012
まとめ
栄養素の汚染は水生生態系を脅かしています. この研究では,葉のの分解率は栄養分レベルによって異なることが明らかになり,機能的な生態系評価の必要性を強調しています.
科学分野:
- エコロジー エコロジー エコロジー
- 環境科学 環境科学
- 水生生態系 水生生態系
背景:
- 過剰な栄養素の負荷は,生物多様性や生地化学的サイクルを変化させ,水生生態系に対する世界的な脅威です.
- 川のネットワークにおける機能的な生態系対策の定量的な評価は,特に大陸規模では,希少である.
研究 の 目的:
- 機能的な生態系評価のギャップを埋めるために,広い栄養分度の範囲で葉の落とし穴の分解を研究する.
- 欧州の河川における生態系における基本的なプロセスに,栄養素の負荷が及ぼす影響を評価する.
主な方法:
- 100のストリームを含む汎ヨーロッパフィールド実験を実施しました.
- 栄養分グラデントの1000倍を超える葉のスレの分解率を評価した.
- 栄養分レベルに関連した機能的な生態系測定値を分析した.
主要な成果:
- 葉のリッター分解は,低濃度および高濃度の栄養素の両方において,著しく減速しました.
- 栄養素の制限は,影響を受けていない流れで明らかであり,中程度の栄養素の添加は分解を刺激しました.
- 高度汚染された川は,葉の落とし穴の分解が抑制されていることを示した.
結論:
- 廃棄物分解率などの機能的な測定は,水生生態系の健康を評価する上で極めて重要です.
- 確立された構造的アプローチは,生態系の健康に関する包括的な理解のために,機能的評価によって補完されるべきである.
- 栄養分グラデントは,河川ネットワークの基本的な生態系プロセスに深い影響を及ぼします.
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