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Updated: Jun 5, 2026

07:26
Visualizing Methane-Cycling Microbial Dynamics in Coastal Wetlands
Published on: January 31, 2025
淡水メタンの排出は,大陸の炭素吸収を相殺する
David Bastviken1, Lars J Tranvik, John A Downing
1Department of Thematic Studies-Water and Environmental Studies, Linköping University, SE-58183 Linköping, Sweden. david.bastviken@liu.se
まとめ
内陸の淡水生態系は,強力な温室効果ガスであるメタン (CH4) を大量に放出しています. この排出量は,推定される陸上の炭素吸収量の相当な部分を相殺し,世界の炭素予算に水生システムを含める必要性を強調しています.
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
- 気候科学 気候科学
背景:
- 湖や川などの内陸水は,メタン (CH4) の源として認識されています.
- これらの源は,世界の温室効果ガス (GHG) 予算に完全に統合されていません.
- 温室効果ガス排出量の正確な会計は,気候変動緩和戦略にとって極めて重要です.
研究 の 目的:
- 内陸淡水生態系からのメタン排出量を定量化するために.
- 世界の温室効果ガス予算に対する淡水CH4排出量の貢献度を評価する.
- 淡水のCH4排出が,地球上の炭素吸収槽に与える影響を決定する.
主な方法:
- 474の多様な淡水生態系からのデータを活用した.
- 最新の世界の水面面積の推定値が組み込まれました.
- 計算されたCH4排出量は,年間テラグラムで表され,二酸化炭素 (CO2) 相当に変換されます.
主要な成果:
- 淡水生態系は,毎年推定103テラグラムのCH4を排出しています.
- この排出量は,CO2 ekvivalentsとして0.65ペタグラムのCに相当します.
- 淡水のCH4排出量は,推定陸上の炭素吸収量の約25%を相殺する.
結論:
- 大陸の温室効果ガス吸収槽は過大評価されているかもしれない.
- 内陸水は,世界の炭素循環の重要な構成要素である.
- 淡水生態系は,世界の炭素と温室効果ガスの予算に明示的に考慮する必要があります.
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