増加する二酸化炭素に対する植物の反応による大陸流出量の増加が予測されています
Richard A Betts1, Olivier Boucher, Matthew Collins
1Met Office Hadley Centre, Fitzroy Road, Exeter EX1 3PB, UK. richard.betts@metoffice.gov.uk
Nature
|August 31, 2007
まとめ
二酸化炭素のレベルが上昇すると,植物の水分保持が強化され,大陸の流れが増加します. この"生理的強制"は,これまで理解していた以上に淡水資源に影響を与え,将来の水不足を緩和する可能性があります.
科学分野:
- 気候科学 気候科学
- 水文学 水文学とは
- 植物生理学 植物生理学
背景:
- 大気中の二酸化炭素の増加は,放射能強制と植物生理学的反応を通じて気候に影響を与えます.
- 植物のストマタル閉塞は,高濃度のCO2下では,透析を減少させ,陸地表面水の利用量を増加させます.
- この"生理的強制"は,20世紀に大陸の流れが上昇したとして観察されています.
研究 の 目的:
- 将来の大陸の流れの変化に対する生理学的強制の貢献を定量化するために.
- CO2に対する植物生理学的反応が,地球規模の水循環に与える影響を評価する.
- 物理的なフォッシングと放射線フォッシングの影響を将来の流れに比較する.
主な方法:
- 植物の構成要素を統合したグローバルな気候モデルを利用した.
- 二酸化炭素濃度の倍増をシミュレートする一連の実験を行いました.
- シミュレートされた大陸の流れと透析の変化を分析した.
主要な成果:
- 二酸化炭素濃度が倍増すると,生理学的影響により,シミュレートされた世界の平均流出量が6%増加した.
- 流出に対するこの生理学的強制効果は,放射的強制効果 (11 +/- 6%) と比較できます.
- 放射力強引のみに基づく将来の評価は,流れの増加を過小評価し,減少を過大評価する.
結論:
- 生理学的強制は水循環に大きく影響し,淡水資源の利用可能性に影響を与えます.
- 生理学的強制を過小評価すると,将来の水資源の予測が不正確になる可能性があります.
- 放射線強制の概念だけでは,温室効果ガスが淡水資源に与える影響を完全に捉えることはできません.
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