Measuring and modelling carbon storage in Quebec boreal black spruce ecosystems under varying fire regimes

加拿大缺乏关于北方生态系统碳动态和北方森林土壤碳稳定性的关键信息。这些信息对于预测生态系统对气候变化的反应和可能影响全球碳循环的反馈的建模工作很重要。我们的多学科团队将测量北方森林中碳动态的关键元素，并随后通过建模练习整合这些信息。来自气候模型的最新信息表明，覆盖加拿大盾的宽阔的黑云杉林带未来可能会受到更频繁的野火干扰。大火也可能没有过去那么猛烈。我们将研究火灾严重程度与木炭生产的数量和质量之间的关系；炭化过程以一种更顽固的形式稳定碳。我们还将调查木炭在土壤剖面中的命运，即它被储存在哪里和如何储存，以及原产地材料(例如苔藓或木材)可能如何影响储存。我们将通过烧毁的树干来测量碳向土壤的输入率，这些树干会逐渐风化并落到土壤中，为有机质做出贡献。将评估火灾严重程度对林下植物(苔藓、草本植物和灌木)早期反应的影响，并将其纳入建模练习。我们将确定可能与严重程度相互作用的非生物因素，以控制植物演替、生产力(生物量)，从而控制碳储存。最后，我们将研究黑云杉幼苗如何在不同的火灾强度下再生。重点将放在再生与生态系统其他组成部分的相互作用上。例如，较低的木炭产量和不太严重的火灾可能对埃里卡灌木有利，因为已经证明木炭可以吸收干扰针叶树营养和生长的酚类化合物。我们将直接与我们的工业合作伙伴合作，评估他们目前回收烧焦木材的战略，然后通常是场地准备和种植。我们需要更多地了解抢救的影响(对苗木和植被再生的潜在影响)，以及在场地准备后重新种植烧毁场地的成功。

Canada lacks critical information about boreal ecosystem carbon dynamics and carbon stability in boreal forest soils. This information is important to modelling efforts to predict responses of ecosystems to climate change and feedbacks that may impinge on the global carbon cycle. Our multidisciplinary team will measure key elements of carbon dynamics in boreal forests and subsequently integrate this information via a modelling exercise. Recent information from climate models suggests that the wide belt of black spruce forest that covers that Canadian Shield may be subject to more frequent wildfire disturbance in the future. Fires may also be less intense than they have been in the past. We will examine the relationship between fire severity and the quantity and quality of charcoal produced; the process of charring stabilizes carbon in a more recalcitrant form. We will also investigate the fate of charcoal in the soil profile, i.e. where and how it is stored, and how the material of origin (for example moss, or wood) might affect storage. We will measure input rates of carbon to the soil via burnt tree boles that gradually weather and fall to the soil to contribute to organic matter. Fire severity effects on early response of the understory (mosses, herbs and shrubs) will be evaluated and integrated into the modelling exercise. We will identify abiotic factors that may interact with severity to control plant succession, productivity (biomass) and therefore carbon storage. Finally, we will examine how black spruce seedlings regenerate under different fire severities. The emphasis will be on interaction of regeneration with other components of the ecosystem. For example, a lower production of charcoal with less severe fires may be beneficial to the ericad shrubs, since charcoal has been shown to absorb phenolic compounds that interfere with the nutrition and growth of conifers. We will work directly with our industrial partners to evaluate their current strategy of salvage of burnt wood, followed generally by site preparation and planting. We need to understand more about the impacts of both salvage (potential impacts on regeneration of both the seedlings and vegetation), as well as the success of replanting burnt sites after site preparation.