Collaborative Research: Testing Paleo to Present Tree Carbon Capture Across Ontogeny, Atmospheric CO2 and Productivity Gradients

这项研究的目标是对大气二氧化碳浓度如何影响森林碳捕获进行现实评估。环境因素，如温度和水的可用性，以及树龄，极大地影响了大气二氧化碳对树木生长和森林碳捕获的影响。古代和现代木材中的年轮将被用作已知时间点上树木生长的档案，当与过去14,000年来对气候和二氧化碳水平的独立估计相结合时，将提供关于树木生长如何对大气二氧化碳做出反应的信息。将在不同树龄和不同环境中采集树心样本。根据现代和古代木材年轮中发现的几个同位素指标的信息，结合对活树的光合作用的测量，将开发出预测广泛林龄和环境条件下碳捕获的模型。到目前为止，只有在有限数量的昂贵的短期实地研究中，才研究了二氧化碳浓度增加对森林生长的影响。这些研究的广泛适用性仍然不确定，因为森林碳捕获在很大程度上依赖于树龄及其与特定地点生长环境的相互作用。这项新的研究为检验和加强对森林生态系统如何应对气候变化的理解提供了一个独特的机会。研究结果将对有关碳排放、土地利用和森林管理的政策决策产生重要影响，以优化碳捕获。

The goal of this research is a realistic assessment of how atmospheric CO2 concentrations affect carbon capture by forests. Environmental factors, such as temperature and water availability, and tree age greatly influence how tree growth and forest carbon capture are influenced by atmospheric CO2. Tree rings in ancient and modern wood will be used as an archive of tree growth at known points in time, and when combined with independent estimates of climate and CO2 levels over the past 14,000 years, will provide information on how tree growth responds to atmospheric CO2. The tree core samples will be collected for different tree ages and in different environments. Models that predict carbon capture over a broad range of forest age and environmental conditions will be developed from information on several isotope indicators found in the tree rings of modern and ancient wood combined with measurements of photosynthesis in living trees.To date, the influence of CO2 enrichment on forest growth has only been studied in young trees exposed to artificially elevated levels of CO2 in a limited number of costly short-term field studies. The broad applicability of these studies remains uncertain because forest carbon capture depends strongly on tree age and its interactions with site-specific growth environments. This new research provides a unique opportunity to test and enhance understanding of how forest ecosystems respond to climate change. The results will have important implications for policy decisions concerning carbon emissions, land-use and forest management to optimize carbon capture.