National carbon flux estimation system for forest ecosystems of Canada

加拿大有400万平方公里的森林生态系统，每年将10亿公吨的碳从大气中固定到植物组织中。森林生态系统还储存了全球活植物中储存的总碳的约6%，而加拿大土壤储存了世界土壤碳储量的约20%。鉴于加拿大的变暖速度是全球平均速度的两倍，了解植物和土壤中储存的碳对气候变化和干扰的脆弱性的举措不仅对加拿大，而且对全球碳预算和循环都是不可或缺的。加拿大的森林包括树木泥炭地地区、大片未管理的北方森林和最南端的树木苔原，对全球变化最敏感，因为该国观察到和预测的气候变化要大得多。随着科学界和政治界对净零排放和净负排放以及基于自然的气候变化解决方案的兴趣日益增加，有一股强大的动力推动建立一个综合的国家森林碳估算系统。在加拿大，如果没有土地部门，特别是森林部门，就无法实现净零排放和净负排放目标。拟议的国家碳估算系统量化了加拿大所有森林生态系统的年度净碳通量，包括通过植物初级生产固定的碳，以及通过土壤呼吸和干扰排放的碳。拟议的碳估算系统预计将促进量化和减少我们对加拿大森林碳循环的理解的不确定性，以评估和监测基于自然的解决方案，以实现净零排放。拟议的系统还将提高我们对直接土地管理行动如何影响森林生态系统碳平衡的理解，为潜在的国家温室气体减排战略提供信息。最重要的是，拟议的碳估算系统将由保护当局部署，以监测为加强和保护加拿大的自然碳汇而采取的行动，并将用于培训下一代科学家，使他们了解如何将动脉情报和天基激光扫描技术纳入森林生态系统研究。

Canada has four million km2 forested ecosystems that fix 1 billion metric tonne carbon from atmosphere into plant tissues every year. The forested ecosystems also store about 6% of the total carbon stored in live plants globally, while Canadian soils store approximately 20% of world soil carbon stocks. Given that Canada is warming twice the global average rate, initiatives to understand the vulnerabilities of carbon stored in plants and soils to climate change and disturbance are indispensable not only for Canada, but also for the global carbon budget and cycle. Canada's forests including areas with treed-peatland, tracts of unmanaged boreal forest, and the most southerly treed Tundra, are most sensitive to global change because of disproportionally greater climate change observed and projected for the country. With increasing scientific and political interest in net-zero and net-negative emissions and nature-based solutions for climate change, there is a strong impetus to develop an integrated national forest carbon estimation system. In Canada, net-zero and net-negative emissions targets cannot be reached without the land sector and in particular forests. The proposed national carbon estimation system quantifies annual net carbon flux of all forest ecosystems in Canada including carbon fixed through plant primary production, and carbon emissions through soil respiration and disturbance. The proposed carbon estimation system is expected to advance the quantification of and reduce uncertainties in our understanding of Canada's forest carbon cycle to evaluate and monitor nature-based solutions to achieve net-zero emissions. The proposed system will also improve our understanding of how direct land management actions impact forest ecosystem carbon balance to inform potential national greenhouse mitigation strategy. Most importantly, the proposed carbon estimation system will be deployed by conservation authorities to monitor actions taken to enhance and protect natural carbon sinks in Canada and will be used to train the next generation scientists on the integration of arterial intelligence and space-based laser scanning technologies to forest ecosystem studies.