呼吸は,欧州の森林における炭素バランスの主要な決定因子である
R Valentini1, G Matteucci, A J Dolman
1University of Tuscia, Department of Forest Environment and Resources, Viterbo, Italy. rik@unitus.it
Nature
|April 29, 2000
まとめ
欧州の森林は,かなりの量の二酸化炭素を吸収し,重要な炭素吸収場として機能します. 炭素吸収は緯度が下がるにつれて増加し,主に生態系の呼吸によって引き起こされ,植生指数や在庫データだけではない.
科学分野:
- エコロジー エコロジー エコロジー
- 環境科学 環境科学
- 林業 林業 林業 林業 林業
背景:
- 地上生物圏の炭素交換は,特に京都議定書の下で,気候変動の評価に不可欠です.
- 以前の地上の炭素増加の推定は間接的な方法に依存しており,制御要因と場所が議論されている.
- 森林の炭素吸収場を理解することは,世界の炭素予算の正確性にとって不可欠です.
研究 の 目的:
- 欧州の森林における生態系の炭素交換の直接的な測定を提示する.
- 欧州の森林生態系が炭素吸収体として機能しているかどうかを確認する.
- 緯度や生態系呼吸などの炭素吸収に影響を与える要因を調査する.
主な方法:
- ヨーロッパの15の森林地帯で,生態系による純炭素交換 (NCE) を直接測定した.
- データ収集は,1996年から1998年まで続いた.
- 緯度との関係で炭素バランス,総原産物,生態系呼吸を分析した.
主要な成果:
- 最も研究された欧州の森林生態系は,年間炭素バランスが6.6トンC/haの吸収からほぼ1トンC/haの放出まで,炭素吸収場として機能することを確認しました.
- 緯度が下がるにつれて,炭素吸収の有意な増加が観察されました.
- 生態系の呼吸が,総原産よりも,一般的に生態系の純炭素交換を決定することを発見した.
結論:
- 欧州の森林は明らかに炭素の吸収源として機能しているが,森林間の大きな変動がある.
- 緯度は炭素吸収に影響を与える重要な要因であり,南部の森林はより高い吸収率を示しています.
- 森林の炭素バランスを正確に評価するには,リモートセンシング (NDVI) または森林在庫データ以上のことが必要であり,生態系の呼吸の役割を強調します.
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