Biogeochemical Model-Data Integration Group, Max Planck Institute for Biogeochemistry, 07745 Jena, Germany.
Science. 2010 Aug 13;329(5993):834-8. doi: 10.1126/science.1184984. Epub 2010 Jul 5.
Terrestrial gross primary production (GPP) is the largest global CO(2) flux driving several ecosystem functions. We provide an observation-based estimate of this flux at 123 +/- 8 petagrams of carbon per year (Pg C year(-1)) using eddy covariance flux data and various diagnostic models. Tropical forests and savannahs account for 60%. GPP over 40% of the vegetated land is associated with precipitation. State-of-the-art process-oriented biosphere models used for climate predictions exhibit a large between-model variation of GPP's latitudinal patterns and show higher spatial correlations between GPP and precipitation, suggesting the existence of missing processes or feedback mechanisms which attenuate the vegetation response to climate. Our estimates of spatially distributed GPP and its covariation with climate can help improve coupled climate-carbon cycle process models.
陆地总初级生产力（GPP）是最大的全球 CO2 通量，驱动着多种生态系统功能。我们使用涡度协方差通量数据和各种诊断模型，提供了一个每年 123±8 百万吨碳（Pg C year(-1)) 的观测基础上的估计值。热带森林和稀树草原占 60%。40%以上有植被的土地的 GPP 与降水有关。用于气候预测的最先进的面向过程的生物圈模型在 GPP 的纬度模式上表现出较大的模型间变异性，并显示出 GPP 和降水之间更高的空间相关性，这表明存在缺失的过程或反馈机制，减弱了植被对气候的响应。我们对空间分布的 GPP 及其与气候的协变的估计可以帮助改进耦合气候-碳循环过程模型。
