摘要
Forests have long life cycles of up to several hundred years and longer.They also have very different growth rates at different stages of their life cycles.Therefore the carbon cycle in forest ecosystems has long time scales,making it necessary to consider forest age in estimating the spatiotemporal dynamics of carbon sinks in forests.The focus of this article is to review methods for combining recent remote sensing data with historical climate data for estimating the forest carbon source and sink distribution.Satellite remote sensing provides useful data for the land surface in recent decades. The information derived from remote sensing data can be used for short-term forest growth estimation and for mapping forest stand age for longterm simulations.For short-term forest growth estimation, remote sensing can provide forest structural parameters as inputs to process-based models,including big-leaf,two-leaf,and multi-layered models. These models use different strategies to upscale from leaf to canopy,and their reliability and suitability for remote sensing applications will be examined here.For long-term forest carbon cycle estimation, the spatial distribution of the forest growth rate（net primary productivity,NPP） modeled using remote sensing data in recent years is a critical input.This input can be combined with a forest age map to simulate the historical variation of NPP under the influence of climate and atmospheric changes. Another important component of the forest carbon cycle is heterotrophic respiration in the soil,which depends on the sizes of soil carbon pools as well as climate conditions.Methods for estimating the soil carbon spatial distribution and its separation into pools are described.The emphasis is placed on how to derive the soil carbon pools from NPP estimation in current years with consideration of forest carbon dynamics associated with stand age variation and climate and atmospheric changes.The role of disturbance in the forest carbon cycle and the effects of forest regrowth after disturbance are also considered in this review.An example of national forest carbon budget estimation in Canada is given at the end.It illustrates the importance of forest stand age structure in estimating the national forest carbon budgets and the effects of climate and atmospheric changes on the forest carbon cycle.
森林有长寿周期直到几百年并且更长。他们也在他们的生命周期的不同阶段有很不同的生长率。因此，在森林生态系统的碳周期有长时间规模，使考虑在估计森林里的碳水池的时间空间的动力学的森林年龄必要。这篇文章的焦点是为为估计森林碳来源和水池分发把最近的遥感数据与历史的气候数据相结合考察方法。卫星遥感在最近的十年为陆地表面提供有用数据。从遥感数据导出的信息能被用于短期的森林生长评价并且为长期的模拟为印射森林看台变老。为短期的森林生长评价，遥感能提供森林是的结构的参数输入到基于过程的模型，包括大叶，二叶，并且 multi-layered 模型。这些模型使用不同策略到从叶高级到为遥感的华盖，和他们的可靠性和适用性，应用将这里被检验。为长期的森林碳周期评价，森林生长率的空间分发(捕捞主要生产率， NPP ) 在最近的年里使用遥感数据建模是批评输入。这输入能与一张森林年龄地图被相结合在气候和大气的变化的影响下面模仿 NPP 的历史的变化。森林碳周期的另一个重要部件是在土壤的不是自养的呼吸，它取决于土壤碳水池以及气候条件的尺寸。进水池的空间分发和它的分离被描述的为估计土壤碳的方法。强调被放在怎么与与看台年龄变化和气候和大气的变化联系的森林碳动力学的考虑在当前的年里从 NPP 评价导出土壤碳水池上。在森林碳周期和在骚乱以后的森林生长的效果的骚乱的角色也在这评论被考虑。在加拿大的国家森林碳预算评价的一个例子在结束被给。它在在森林碳周期上估计国家森林碳预算和气候和大气的变化的效果说明森林看台年龄结构的重要性。
