湖のリン酸塩濃度について
J J Hudson1, W D Taylor, D W Schindler
1Department of Biological Sciences, University of Alberta, Edmonton, Canada. hudsonje@ene.gov.on.ca
Nature
|July 14, 2000
まとめ
新しい放射線バイオアッセイでは,湖のピコモラーリン酸塩濃度が,以前の推定値より著しく低いことが明らかになりました. 微生物は,これらの低い栄養分レベルでも急速な周回を達成し,既存の生態学的モデルに挑戦します.
科学分野:
- 環境科学 環境科学
- 微生物学 微生物学とは
- リムテクノロジーとは
背景:
- リン酸は,水生生態系における微生物の生産を制限する重要な栄養素です.
- リンが限られた水域でのリン酸塩濃度測定のための既存の方法は,しばしば実際のレベルを過大評価します.
- 精密なリン酸塩測定は,微生物の動態と栄養素の循環を理解するために不可欠です.
研究 の 目的:
- 様々な湖系におけるリン酸塩濃度の正確な測定のための新しい放射生物測定法を開発し,適用する.
- 新しい測定値を既存の光譜光度測定およびリグラー放射生物測定データと比較する.
- リン酸濃度,総リン酸,湖のトロフィック状態との関係を調査する.
主な方法:
- フォスファート濃度を測定するために,新しい安定状態放射生物測定法が採用されました.
- 調査は,様々な湖の環境で実施されました.
- データは,既存の文献値と組み合わせて分析されました.
主要な成果:
- 酸塩濃度は,標準的な方法を使用して以前に推定されたよりも数桁低いことが判明しました.
- 微生物コミュニティは,ピコモラーリン酸塩濃度で急速な転移率を示した.
- 総リン量が増えたにもかかわらず,リン酸の比率はオリゴトロフ湖からユートロフ湖へと減少した.
結論:
- 新しい放射生物測定法により,水生システムにおける生物利用可能なリン酸塩のより正確な評価が可能です.
- 微生物の生命は,非常に低いリン酸濃度でも繁栄し,急速な活動を示すことができます.
- この発見は,水中の環境における栄養素制限と微生物の反応を再評価することを必要としています.
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