Dept. of Geography and Environment, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada.
Canadian Forest Service, Great Lakes Forestry Centre, Sault Ste. Marie, ON P6A 2E5, Canada.
Sci Total Environ. 2021 May 15;769:145212. doi: 10.1016/j.scitotenv.2021.145212. Epub 2021 Jan 17.
Boreal peatlands store a disproportionately large quantity of soil carbon (C) and play a critical role within the global C-climate system; however, with climatic warming, these C stores are at risk. Increased wildfire frequency and severity are expected to increase C loss from boreal peatlands, contributing to a shift from C sink to source. Here, we provide a comprehensive review of pre- and post-fire hydrological and ecological interactions that affect the likelihood of peatland burning, address the connections between peatland fires and the C-climate cycle, and provide a conceptual model of peatland processes as they relate to wildland fire, hydro-climate, and ecosystem change. Despite negative ecohydrological feedback mechanisms that may compensate for increased C loss initially, the cumulative effects of climatic warming, anthropogenic peatland fragmentation, and subsequent peatland drying will increase C loss to the atmosphere, driving a positive C feedback cycle. However, the extent to which negative and positive feedbacks will compensate for one another and the timelines for each remains unclear. We suggest that a multi-disciplinary approach of combining process knowledge with remotely sensed data and ecohydrological and wildland fire models is essential for better understanding the role of boreal peatlands and wildland fire in the global climate system.
北方泥炭地储存了不成比例的大量土壤碳 (C)，在全球碳-气候系统中发挥着关键作用；然而，随着气候变暖，这些碳储量面临风险。野火频率和严重程度的增加预计将增加北方泥炭地的碳损失，导致其从碳汇转变为碳源。在这里，我们全面回顾了影响泥炭地燃烧可能性的火灾前后水文和生态相互作用，探讨了泥炭地火灾与碳-气候循环之间的联系，并提供了一个与野火、水文气候和生态系统变化有关的泥炭地过程概念模型。尽管可能存在负的生态水文学反馈机制来最初补偿增加的碳损失，但气候变暖、人为泥炭地破碎化以及随后的泥炭地干燥的累积效应将增加向大气的碳损失，从而导致正的碳反馈循环。然而，负反馈和正反馈将如何相互补偿，以及每个反馈的时间表仍然不清楚。我们建议，将过程知识与遥感数据以及生态水文学和野火模型相结合的多学科方法对于更好地理解北方泥炭地和野火在全球气候系统中的作用至关重要。
