大規模で持続的な炭素が世界の森林に沈む
Yude Pan1, Richard A Birdsey, Jingyun Fang
1U.S. Department of Agriculture Forest Service, Newtown Square, PA 19073, USA. ypan@fs.fed.us
まとめ
世界の森林は,年間2.4ペタグラムの炭素を吸収し,重要な炭素吸収場として機能しています. 不確実性にもかかわらず,この森林の炭素吸収場は,大気中の二酸化炭素レベルを軽減する上で重要な役割を果たしています.
科学分野:
- * 地球システム科学 地球システム科学
- * 森林生態学 森林生態学
- * 生物地球化学のサイクル
背景:
- * 地球上の炭素吸収槽の規模と地理的分布は不明である.
- *森林は,地球規模の炭素循環の重要な構成要素である.
- *近年,陸上の生態系によって,かなりの量の炭素が吸収されている.
研究 の 目的:
- * 1990年から2007年までの世界の森林の炭素吸収量を定量化する.
- * 熱帯地域における土地利用の変化が炭素の流れに与える影響を評価する.
- * 排出量と封じ込めを考慮して,世界の森林における純炭素吸収量を決定する.
主な方法:
- * 森林在庫データを利用して,地球規模の沈殿地の推定を行いました.
- * 組み込まれた長期の生態系炭素研究.
- * 量化された熱帯森林伐採の排出量と森林再生の沈没.
主要な成果:
- * 推定の世界的な森林沈殿量は,年間2.4±0.4ペタグラムの炭素 (Pg C年 ((-1)) である.
- * 熱帯の土地利用の変化の源は,年間1.3 ± 0.7 Pg C ((-1) であった.
- * 熱帯地域の不確実性が高く,1.1 ± 0.8 Pg C year ((-1) の世界の森林沈没を計算した.
結論:
- *世界の森林の炭素吸収量は,他の主要な炭素循環構成要素と比べるとかなり大きい.
- * 熱帯森林伐採は,森林の再生によって部分的に相殺される重要な炭素源を表しています.
- * 熱帯の炭素流動の不確実性は,監視と研究を改善する必要性を強調しています.
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