土壤碳分解的温度敏感性和对气候变化的反
Eric A Davidson1, Ivan A Janssens
1The Woods Hole Research Center, PO Box 296, Woods Hole, Massachusetts 02543, USA. edavidson@whrc.org
Nature
|March 10, 2006
概括
全球土壤碳储量比大气中含有更多的碳. 气候变化影响土壤分解速度,但由于复杂的土壤过程,对大气碳的净影响仍然不确定.
科学领域:
- 土壤科学 土壤科学
- 气候科学 气候科学
- 生物地质化学生物地质化学
背景情况:
- 土壤储存了大量的全球碳,超过了大气储存库.
- 讨论了气候变化对土壤碳动态的影响,并讨论了潜在的正面或负面反循环.
- 了解土壤碳反对于气候变化预测至关重要.
研究的目的:
- 为了研究土壤碳分解的温度敏感性.
- 阐明影响土壤碳对气候变化的反效应的因素.
- 为了解决关于土壤碳对变暖的反应缺乏共识的问题.
主要方法:
- 分析各种土壤有机化合物及其分解动力学.
- 对观察到的"明显"温度敏感性进行环境约束的评估.
- 评估土壤碳分解的内在与表面温度灵敏度.
主要成果:
- 在土壤有机化合物中,分解的内在温度敏感性差异很大.
- 环境限制显著降低了观察到的分解温度灵敏度.
- 这些约束本身可能是气候敏感的,增加了复杂性.
结论:
- 气候变化对全球土壤碳库存的净影响仍然不确定.
- 准确的气候建模需要更好地了解土壤碳分解温度敏感性.
- 需要进一步的研究来解开内在和表面温度敏感性及其气候相互作用.
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