Evaluating the capabilities of Eastern Canadian forest ecosystems to sequester atmospheric CO2 and their response to climate change

大气中二氧化碳和其他温室气体水平的上升引起了科学家和政策制定者的关注，因为它们捕获了从地球发出的长波辐射，导致我们的大气变暖。最近发布的第四次联合国IPCC报告得出结论，气候系统变暖是明确的，很可能是由于人为温室气体。加拿大将其森林视为潜在的碳汇。然而，加拿大政府尚未决定是否采用生物碳汇方案来抵消化石燃料排放，因为生物碳汇，特别是森林碳汇的不确定性。未来气候变暖可能对加拿大森林生态系统的健康和生长产生严重影响，目前气候变暖已经严重影响到加拿大森林生态系统。该战略拨款提案（SGP）的重点是评估加拿大东部三个关键森林生态系统的能力，针叶树年龄序列（65，35，5岁），落叶和混合木林，以封存大气中的CO2及其对未来气候变化（如变暖，干旱等）的反应。该小额赠款方案还将侧重于开发一个氮循环模型，并将其纳入加拿大陆地生态系统模型。CTEM+N将用于探索自然和人为影响（即增加氮沉降，CO2施肥，严重干旱和洪水事件，温度压力等）对所有三个（针叶树，落叶和混合木）森林生态系统在各种未来气候变化情景下模拟碳和水交换的影响。量化加拿大东部所有三个主要森林生态系统对气候变化的反应将使环境规划者和管理者能够制定战略，帮助这些生态系统更好地适应未来的气候变化。在加拿大全球气候模型中实施CTEM+N将提供一个评估工具，为政策制定提供未来气候情景，并帮助加拿大履行其国际义务。

Rising levels of atmospheric CO2 and other greenhouse gases are a concern to scientists and policy-makers, because they trap longwave radiation emitted from Earth, contributing to our atmosphere's warming. Recently released fourth UN IPCC report concluded that warming of the climate system is unequivocal and very likely due to anthropogenic greenhouse gases. Canada considers its forests as a potential carbon (C) sink. However, Canadian government has not yet decided whether it will adopt the biological C sink option to offset fossil fuel emissions, due to uncertainties associated with biological C sinks, particularly in forests. Future warming of the climate may have a severe impact on the health and growth of Canadian forest ecosystems, which are already being seriously affected by current warmer climatic conditions. This Strategic Grant Proposal (SGP) focuses on evaluating the capabilities of three key Eastern Canadian forest ecosystems, a conifer age-sequence (65, 35, 5 year old), deciduous, and mixedwood stands, to sequester atmospheric CO2 and their response to future climate change (e.g. warming, drought, etc.). This SGP would also focus on developing and incorporating a nitrogen (N) cycle model in the Canadian Terrestrial Ecosystem Model (CTEM+N). CTEM+N will be used to explore the impact of natural and anthropogenic effects (i.e. increased N deposition, CO2 fertilization, severe drought and flooding events, temperature stresses, etc) on simulated C and water exchanges in all three (conifer, deciduous and mixedwood) forest ecosystems under various future climate change scenarios. Quantification of the responses of all three major Eastern Canadian forest ecosystems to climate change would equip environmental planners and managers to develop strategies that may help these ecosystems to better adapt to future climate change. Implementation of CTEM+N in the Canadian Global Climate Model would provide an assessment tool to generate scenarios of future climate for policy development and help Canada meet its international obligations.