森林におけるOH反応性の欠如:未知の活性生物学的VOCの証拠
Piero Di Carlo1, William H Brune, Monica Martinez
1Department of Meteorology, Pennsylvania State University, University Park, PA 16802, USA. piero.dicarlo@aquila.infn.it
まとめ
生物学的揮発性有機化合物 (BVOCs) の森林からの排出は,オゾンとエアロゾールに寄与する. 未知の反応性のあるBVOC,おそらくテルペンは,ミシガン州の森林研究で観察された予想以上に高いOH反応性を説明します.
科学分野:
- 大気化学 大気化学
- 森林生態学 森林生態学 森林生態学
- 環境科学 環境科学
背景:
- イソプレンとテルペンを含む森林からの生物学的揮発性有機化合物 (BVOC) は,大気化学に影響を与えます.
- トロポスフィアのオゾンとエアロゾールの形成は,森林の排出によって影響を受けます.
- OHの反応性は,大気中の酸化過程の重要な指標である.
研究 の 目的:
- ミシガン州北部の森で計測された総OH反応性と予想された総OH反応性の差異を調査する.
- 測定されていないOH反応性の潜在的な源を特定するために.
- 未知の反応性BVOCが欠けているOH反応性に貢献するという仮説を検証する.
主な方法:
- 森林環境における総OH反応性の直接測定.
- テルペンを含むBVOCの排出量の定量化.
- 温度,BVOC排出量,およびOH反応性の関係に関する分析.
主要な成果:
- 測定された総OH反応性は,既知の化合物に基づいて予測されたより著しく高かった.
- "欠けている"OHの反応性は,環境温度とともに増加した.
- ターペンやその他のBVOCの排出量も温度とともに増加した.
結論:
- 未知の反応性BVOCは,観測された"欠落した"OH反応性の原因である可能性が高い.
- テルペンは,これらの未知の反応性化合物の潜在的な候補である.
- 森林の排出量は,大気化学における重要な,そして潜在的に過小評価されている役割を果たしています.
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