土壤呼吸适应在高草草原的温暖化
1Department of Botany and Microbiology, University of Oklahoma, Norman, Oklahoma 73019, USA. yluo@ou.edu
Nature
|October 26, 2001
概括
变暖可能不会像预期的那样增加温室气体排放. 土壤呼吸,气候反的一个关键因素,似乎适应更高的温度,可能削弱其影响.
科学领域:
- 生态生态学 生态生态学
- 气候科学 气候科学
- 生物地质化学生物地质化学
背景情况:
- 政府间气候变化专门委员会 (IPCC) 的报告预测全球气候变暖显著.
- 陆地生态系统可能会释放更多的温室气体,从而产生积极的气候反循环.
- 目前的模型假设土壤呼吸的温度敏感性在更温暖的气候下保持不变,这一假设需要验证.
研究的目的:
- 为了研究土壤呼吸对高草原生态系统中人工变暖的反应.
- 测试土壤呼吸的温度敏感性在未来的气候条件下是稳定的假设.
主要方法:
- 进行了一项实验,将大约2摄氏度的人工变暖应用于高高的草原.
- 测量土壤呼吸,包括根和异质的呼吸.
主要成果:
- 在实验加热下,土壤呼吸的温度灵敏度下降或适应.
- 这种适应效应在更高的温度下更加明显.
结论:
- 土壤呼吸对变暖的适应可能会减少陆地碳循环和气候之间的积极反.
- 结合这种反的未来气候预测可能需要修订.
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