気候変動. 気候変動. 北極の茂みが増えている
1US Army Cold Regions Research & Engineering Laboratory-Alaska, PO Box 35170, Fort Wainwright, Alaska 99703, USA. msturm@ccrel.usace.army.mil
Nature
|June 1, 2001
まとめ
北極の温暖化は,アラスカの灌木の拡大を促している. この50年にわたる茂みの大幅な増加は,ツンドラ生態系におけるエネルギーバランス,雪の分布,炭素の貯蔵に影響を及ぼしています.
科学分野:
- 北極の生態学 北極の生態学
- 気候変動科学 気候変動科学
- リモートセンシング (リモートセンサー)
背景:
- アラスカの北極の温暖化は,ここ数十年で加速しています.
- 茂みが増えれば,ツンドラ植物の生産性が向上すると予測されています.
- 証拠は,北極の風景の潜在的進行中の移行を示唆しています.
研究 の 目的:
- 北極で広範囲に広がる灌木の豊富さの増加の証拠を提示するために.
- 過去50年にわたる灌木覆いの変化を分析するために.
- 北極の生態系に対する灌木の拡大の影響を理解する.
主な方法:
- 歴史的空中写真と現代の空中写真の比較.
- 320kmの横断部分における景観の変化の分析.
- 灌木の繁殖傾向の評価.
主要な成果:
- 北極の景観全体で灌木の豊富さの広範な増加を示した.
- この拡大を過去50年間で320km以上記録した.
- 観測された変化は,ツンドラ植物の潜在的な変化を示しています.
結論:
- 灌木の拡大は,北極の夏のエネルギー分割と冬の雪の分布を大幅に変化させます.
- 灌木覆いの増加は,現在二酸化炭素の純源と見なされている地域で炭素貯蔵を強化する可能性があります.
- この発見は,気候温暖化に対する北極の生態系のダイナミックな反応を強調しています.
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