高草の草原の温暖化への土壌呼吸の適応
1Department of Botany and Microbiology, University of Oklahoma, Norman, Oklahoma 73019, USA. yluo@ou.edu
Nature
|October 26, 2001
まとめ
温暖化が予想されるほど温室効果ガスの排出量を増加させないかもしれない. 気候フィードバックの重要な要因である土壌呼吸は,より高い温度に適応し,潜在的にその影響を弱めるように見える.
科学分野:
- エコロジー エコロジー エコロジー
- 気候科学 気候科学
- バイオジオケミストリー バイオジオケミストリー
背景:
- 気候変動に関する政府間パネル (IPCC) の報告書は,地球温暖化が著しく増加すると予測しています.
- 陸上の生態系はより多くの温室効果ガスを放出し,気候のポジティブなフィードバックループを生み出します.
- 現在のモデルでは,土壌呼吸の温度感受性が温暖な気候でも一定であると仮定しており,この仮定は検証が必要である.
研究 の 目的:
- 高草原の草原生態系における人工温暖化に対する土壌呼吸の反応を調査する.
- 土壌呼吸の温度感度が将来の気候条件下では安定しているという仮定を検証する.
主な方法:
- 高草の草原に約2度Cの人工温暖化を適用した実験を行いました.
- 根の呼吸とヘテロトロフの呼吸の両方を含む,測定された土壌呼吸.
主要な成果:
- 土壌呼吸の温度感受性は,実験的な温暖化下で減少または適応した.
- この適応効果は,より高い温度でより顕著であった.
結論:
- 温暖化への土壌呼吸の適応は,地球上の炭素循環と気候の間の肯定的なフィードバックを減少させる可能性があります.
- このフィードバックを組み込む将来の気候予測は,改定する必要があるかもしれません.
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