まとめ
熱帯雨林の伐採によって1980年に排出された炭素は,以前に推定されたよりも少ない. 生態系の回復を考慮した新しいモデリングは,これらの重要な生態系から排出される二酸化炭素の純流量が少なくなることを示唆しています.
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:
- 熱帯雨林は,世界の炭素循環において重要な役割を果たしています.
- 土地利用の変化による炭素排出量の正確な推定は,大気中のCO2レベルを理解するために不可欠です.
- 以前,熱帯森林伐採による炭素フルースの推定値は大きく異なっていた.
研究 の 目的:
- 1980年に熱帯の生態系から大気中に排出された二酸化炭素の純流量を定量化するためです.
- 土地利用の変化,特に森林伐採が植生と土壌の炭素に与える影響を評価する.
- データの不確実性に対する炭素流量推定の感受性を評価する.
主な方法:
- 植生と土壌の炭素への土地利用の変化の影響をシミュレートするコンピュータモデルを使用しました.
- トロピカルフォレストの伐採による炭素排出の主要な決定因子に関する新しいデータを組み込みました.
- モデリングに生態系の回復プロセスを含めた.
主要な成果:
- 1980年,熱帯は0.4から1.6×1015グラムの炭素の純供給源であった.
- 土壌の有機物質の減少は,0.1から0.3x10^15gを寄与した.
- クリアされた植物の燃焼と腐敗は,0.3から1.3×10^15グラムの炭素を放出しました.
結論:
- 熱帯から放出される生物学的炭素の新推定値は,以前の多くの数字よりも低い.
- 改訂された見積もりは,潜在的によりバランスのとれたグローバルな炭素予算を示唆しています.
- 減少したバイオマス推定値,低クリアリング率,生態系回復の含有が,低流量値に寄与した.
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