世界的な森林破壊:大気中の二酸化炭素への貢献
Science (New York, N.Y.)
|December 9, 1983
まとめ
森林伐採は大気中の二酸化炭素レベルに大きな影響を及ぼし,1960年まで化石燃料よりも多くの炭素を放出しました. この研究は,気候変動緩和戦略に意味を持つ,主要な生物学的ドライバーとしての森林破壊を強調しています.
科学分野:
- 環境科学 環境科学
- 大気化学 大気化学
- エコロジー エコロジー エコロジー
背景:
- 地球上の生物は,大気中の二酸化炭素 (CO2) の調節に重要な役割を果たしています.
- 歴史的なデータは,土地利用の変化,特に森林伐採による炭素の排出量が大幅に増加していることを示しています.
研究 の 目的:
- 1860年から1980年までの森林伐採による炭素の純排出量を定量化する.
- 大気中のCO2に対する生物学的源と化石燃料の相対的な貢献度を評価する.
- 森林伐採が,CO2の空中分量に及ぼす影響を評価する.
主な方法:
- 森林伐採と炭素排出に関する過去のデータの分析.
- バイオタと土壌から排出される炭素と,化石燃料からの排出量の比較.
- 人口増加に基づく将来のバイオティック・カーボン放出のモデリング.
主要な成果:
- 森林の伐採 (1860年−1980年) から排出される世界の純炭素排出量は,135-228×10^15グラムと推定されている.
- 1980年には,森林伐採が排出された1.8-4.7 x 10^15グラムの炭素の80%近くを占めていた.
- バイオティック・カーボンの排出量は,約1960年まで,化石燃料の排出量を上回っていた.
- 1980年の総炭素排出量の空中分子は,一般的に想定されている化石燃料排出量の50%ではなく,おそらく22%から43%であった.
結論:
- 森林伐採は大気中のCO2に影響を及ぼす主要な生物学的要因であり,森林の炭素貯蔵が増加し,排出を相殺するという理論に反する.
- 森林が枯渇する前に,予想される生物学的炭素の排出量は,年間9×1015グラムに達する可能性があります.
- 化石燃料の削減と森林管理を通じて大気中のCO2の蓄積を制限する機会は過小評価されている可能性があります.
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