大気中のオゾン濃度は,樹木や作物の種における純光合成を減少させます
Science (New York, N.Y.)
|November 1, 1985
まとめ
地下層オゾンは,中程度のレベルであっても,作物や木々の植物 fotosynthesis を大幅に害します. 酸性雨は悪影響を示さなかったため,オゾンが植物健康に影響を与える主要な大気汚染物質であることを示唆した.
科学分野:
- 環境科学 環境科学
- 植物生理学 植物生理学
- 農業科学 農業科学とは
背景:
- オゾンと酸性雨は,生態系に影響を与える重要な大気汚染物質です.
- 農作物や木の光合成に及ぼす影響を理解することは,農業と森林の健康にとって極めて重要です.
研究 の 目的:
- 現実的なオゾン濃度に対する作物や樹種の光合成反応を評価する.
- 樹木の光合成にシミュレートされた酸性雨の影響を決定するために.
- オゾンと酸性雨の潜在的相互作用を調査する.
主な方法:
- 3種の作物と4種の樹木を様々なオゾン濃度にさらした.
- 木種にシミュレートされた酸雨を施した.
- 測定された純光合成速度とストマト伝導率.
主要な成果:
- オゾンへの曝露は,すべての試験種において,純光合成を減少させた.
- 酸雨は樹木の光合成に悪影響を及ぼさなかった.
- オゾンと酸性雨の影響の間の相互作用は観察されなかった.
- 経口伝導性が高い種は,オゾンに対してより高い感受性を示した.
結論:
- オゾンは,環境レベルでも,様々な植物種の光合成に悪影響を及ぼします.
- 酸性雨は,これらの実験条件下で樹木の光合成に重大な脅威を与えない.
- 米国東部のような地域における広範囲にわたるオゾン汚染は,作物と木の光合成率を低下させ,潜在的に収穫と成長に影響を及ぼしている可能性があります.
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