不稳定和抗性土壤有机物池对温度变化的反应类似
Changming Fang1, Pete Smith, John B Moncrieff
1School of Biological Sciences, University of Aberdeen, Aberdeen AB24 3UU, UK. c.fang@abdn.ac.uk
Nature
|January 7, 2005
概括
土壤有机物 (SOM) 分解对温度敏感,影响气候变化预测. 抗性土壤碳池的反应类似于不稳定池的反应,这表明两者都将受到全球变暖的影响.
科学领域:
- 土壤科学 土壤科学
- 生物地质化学生物地质化学
- 气候变化研究 气候变化研究
背景情况:
- 土壤有机物 (SOM) 的分解及其温度敏感性对于预测气候变化对土壤碳储存的影响至关重要.
- 目前的理解表明,不稳定的碳对温度敏感,而耐性碳则不是,这影响了全球碳库存预测.
- 耐性碳池的温度敏感性对于准确的全球变暖影响评估至关重要.
研究的目的:
- 为了研究土壤有机物分解的温度敏感性,特别是对于抗性碳池.
- 为了确定耐性土壤碳是否与不稳定碳相比对温度变化做出不同的反应.
- 改进气候变化对土壤储存碳的影响预测.
主要方法:
- 在受控,变化的温度条件下化土壤.
- 测量土壤基本呼吸速率作为SOM分解的指标.
- 分析由土壤深度,采样方法和化时间影响的SOM组件.
主要成果:
- 土壤有机物分解率受到与土壤深度,采样方法和化时间相关的SOM组件的显著影响.
- 重要的是,SOM分解的温度灵敏度不受这些因素的影响.
- 这表明,抗性有机物池的温度灵敏度与不稳定池的温度灵敏度相似.
结论:
- 不稳定和抗性土壤有机物池都表现出类似的温度敏感性.
- 全球变暖可能会同样影响两种类型的SOM,这与一些现有假设相反.
- 这些发现需要对在气候变化下预测未来土壤碳库存的模型进行修订.
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