地球的二氧化碳总吸收:全球分布和与气候的共变
Christian Beer1, Markus Reichstein, Enrico Tomelleri
1Biogeochemical Model-Data Integration Group, Max Planck Institute for Biogeochemistry, 07745 Jena, Germany. christian.beer@bgc-jena.mpg.de
Science (New York, N.Y.)
|July 7, 2010
概括
陆地原始生产总量 (GPP) 是最大的二氧化碳流量,使用观测数据估计为每年123 Pg C. 这项研究突出了GPP的重点.
科学领域:
- 地球系统科学 地球系统科学
- 生态生态学 生态生态学
- 生物地质化学生物地质化学
背景情况:
- 陆地总初级产量 (GPP) 是全球最大的二氧化碳 (CO2) 流量,从根本上影响生态系统功能.
- 准确量化GPP对于了解全球碳循环及其与气候相互作用至关重要.
- 现有的生物圈模型在模拟GPP模式时显示出显著的差异,表明需要改进模型组件.
研究的目的:
- 提供基于观测的全球陆地GPP的估计.
- 调查GPP与气候因素,特别是降水之间的关系.
- 为了确定气候变化预测当前生物圈模型的局限性.
主要方法:
- 利用来自全球多个站点的状共变量流量数据.
- 采用各种诊断模型来处理和分析流量数据.
- 估计了空间分布的GPP,并分析了它与气候变量之间的共变性.
主要成果:
- 基于观察的GPP估计为每年123±8倍克的碳 (Pg C年−1) 得到了推导.
- 热带森林和草原的贡献很大,占总GDP的60%.
- 大约40%的植被地表现出GPP受到降雨模式的强烈影响.
结论:
- 目前的生物圈模型可能无法完全捕捉植被对气候的反应,因为缺少的过程或反机制.
- 来自GPP的估计和它们的气候共变量为改进气候碳循环模型提供了有价值的数据.
- 改进的模型对于更准确的气候变化预测和理解生态系统动态至关重要.
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