Hayat Amaury, Hacket-Pain Andrew J, Pretzsch Hans, Rademacher Tim T, Friend Andrew D
Department of Pure Mathematics and Mathematical Statistics, Centre for Mathematical Sciences, University of Cambridge Cambridge, UK.
Fitzwilliam CollegeCambridge, UK; St Catherine's CollegeOxford, UK.
Front Plant Sci. 2017 Mar 21;8:182. doi: 10.3389/fpls.2017.00182. eCollection 2017.
Increasing CO concentrations are strongly controlled by the behavior of established forests, which are believed to be a major current sink of atmospheric CO. There are many models which predict forest responses to environmental changes but they are almost exclusively carbon source (i.e., photosynthesis) driven. Here we present a model for an individual tree that takes into account the intrinsic limits of meristems and cellular growth rates, as well as control mechanisms within the tree that influence its diameter and height growth over time. This new framework is built on process-based understanding combined with differential equations solved by numerical method. Our aim is to construct a model framework of tree growth for replacing current formulations in Dynamic Global Vegetation Models, and so address the issue of the terrestrial carbon sink. Our approach was successfully tested for stands of beech trees in two different sites representing part of a long-term forest yield experiment in Germany. This model provides new insights into tree growth and limits to tree height, and addresses limitations of previous models with respect to sink-limited growth.
不断增加的二氧化碳浓度受到现有森林行为的强烈控制，现有森林被认为是当前大气中二氧化碳的主要汇。有许多模型预测森林对环境变化的响应，但它们几乎完全由碳源（即光合作用）驱动。在此，我们提出了一个针对单棵树木的模型，该模型考虑了分生组织的内在限制和细胞生长速率，以及树木内部影响其直径和高度随时间增长的控制机制。这个新框架基于基于过程的理解，并结合通过数值方法求解的微分方程构建。我们的目标是构建一个树木生长的模型框架，以取代动态全球植被模型中的现有公式，从而解决陆地碳汇问题。我们的方法在德国一个长期森林产量实验的两个不同地点的山毛榉林分中得到了成功测试。该模型为树木生长和树木高度限制提供了新的见解，并解决了先前模型在汇限制生长方面的局限性。
