アマゾンの森林における炭素:予期せぬ季節的な流れと,干渉による損失
Scott R Saleska1, Scott D Miller, Daniel M Matross
1Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA 02138, USA. saleska@fas.harvard.edu
まとめ
ブラジルの古い森林は,予想に反して,毎年二酸化炭素を失っていた. 3年間にわたって観測されたこの純炭素損失は,これらの森林における炭素の吸収が,以前に推定されたよりも低いことを示唆しています.
科学分野:
- エコロジー エコロジー エコロジー
- 森林科学 林業科学 林業科学
- 炭素循環に関する研究
背景:
- 旧生林は重要な炭素吸収源である.
- 炭素循環におけるそれらの役割を理解することは,気候変動の緩和に不可欠です.
- 以前の研究では,しばしば,未干渉の古い成長の森林が一貫した炭素吸収源であると仮定しています.
研究 の 目的:
- ブラジルのサンタレムにある2つの旧生林地における二酸化炭素 (CO2) の生態系の交換量を測定するために.
- 季節的な炭素動態を調査し,木の成長とモデル予測と比較する.
- これらの森林の長期的な炭素バランスを評価する.
主な方法:
- エディコバリアンス法を使用して,3年間にわたるCO2の生態系交換を測定しました.
- 炭素流量測定を確認するために生体測定を行った.
- 炭素の増量と減少の季節的変動を分析した.
主要な成果:
- 雨季の二酸化炭素の純損失と乾季の純損失が観測され,典型的な季節的パターンが逆転した.
- 年間1ヘクタールあたり1.3メガグラムの炭素の3年間の平均純炭素損失を計算しました.
- バイオメトリックデータにより,炭素の純損失が確認され,最近の干渉による一時的な影響が示唆された.
結論:
- 研究された古い成長の森林は,季節的な成長サイクルとモデル予測に反して,炭素の純損失を経験しています.
- 旧生林におけるエピソード的干渉は,干渉されていない場所から以前に推定されたより低い純炭素収縮につながる可能性があります.
- これらの発見は,森林の炭素吸収の可能性を評価する際に,破壊の歴史を考慮することの重要性を強調しています.
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