Forest resilience in the 21st century: Adapting to altered fire regimes and climate change

21 世纪的森林恢复能力：适应改变的火灾状况和气候变化

• 批准号: RGPIN-2020-06310
• 负责人: Daniels, Lori
• 金额: $ 4.74万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=740724
• 关键词: Forest; resilience; 21st; century; Adapting

Wildfire is the most important natural disturbance agent affecting global forests. Changes to fire regimes, triggered by subtle changes in climate and human impacts, have potential major impacts on ecosystems. The current rate and magnitude of climate change have the potential to jeopardize ecological resilience so that disturbed ecosystems are unable to recover. Understanding fire regimes and their drivers is essential to adapt, given the potential consequences of climate change. Worldwide, intense and fast-moving megafires have burned with severe social, economic, and ecological impacts. The record-breaking wildfires of 2017 in British Columbia burned 1.2 million hectares, mostly in montane forests. These fast-moving, intense fires had high-severity effects, even in montane forests with strong evidence of past low-severity surface fire regimes. These extreme wildfires incite three ecological questions:    Have fire regimes been altered beyond historical limits?    Is forest resilience to fire compromised?    How do we adapt management to improve forest resilience? My research shows that fire regimes in montane forests differs from those in boreal forests in meaningful ways. Mixed-severity fire regimes include frequent surface fires and periodic crown fires and historically dominated montane forests in British Columbia and the foothills of Alberta. Improved understanding of the dynamics and drivers of mixed-severity fire regimes is urgently needed to assure the resilience of these forests. Over the next 5 years my research team and I will complete a series of inter-related research projects: Phase 1 will expand our network of fire history reconstructions into the driest forests in BC. We will use multiple lines of tree-ring evidence to compare fire history among these study areas. We will determine if changes to historic fire regimes are pervasive among climatic regions and the consequences for forest composition and structure. Phase 2 combines western science with Indigenous knowledge for a comprehensive understanding of cultural fire and its ecological effects. Phase 3 addresses the consequences of eliminating surface fires from forest stands and landscapes. Combining fieldwork and air photograph analysis with fire behaviour modelling, we will quantify the amount of fuels that have built up and the probability of forests to burn as high intensity crown fires. The final phase of this research assesses how climate change exacerbates these problems. Three PhD, 3 MSc and c.14 undergraduate students will be integrally involved with this research. Ultimately, we will generate new knowledge on the drivers of historical fire regimes, the degree to which they have changed, and the consequences to forest resilience. Our work will help prioritize areas for fuels mitigation and ecological restoration. It also provides a much-needed baseline to ensure adaptive management is effective at improving forest resilience to climate change.

野火是影响全球森林的最重要的自然干扰因素，由气候和人类影响的微妙变化引发的火灾状况的变化对生态系统具有潜在的重大影响。鉴于气候变化的潜在后果，受干扰的生态系统无法恢复。扑灭野火2017 年，不列颠哥伦比亚省的大火烧毁了 120 万公顷土地，其中大部分发生在山地森林中，即使在有明显证据表明过去发生过低严重程度地表火灾的山地森林中，这些极端的野火也引发了三场生态火灾。问题： 火灾制度的改变是否超出了历史极限？ 森林的抵御火灾能力是否受到损害？ 我们如何调整管理以提高森林的抵御能力？研究表明，山地森林的火灾状况与北方森林的火灾状况存在显着差异，包括频繁的地表火灾和周期性的树冠火灾，以及历史上主要发生在不列颠哥伦比亚省和阿尔伯塔省山麓地区的火灾状况。迫切需要混合严重程度的火灾机制的驱动因素，以确保这些森林的恢复能力。在接下来的五年里，我和我的研究团队将完成一系列相互关联的研究项目：第一阶段将扩大我们的网络。我们将使用多行树木年轮证据来比较这些研究区域的火灾历史，我们将确定历史火灾状况的变化是否在气候区域中普遍存在，以及对森林构成的影响。第二阶段将西方科学与本土知识相结合，以全面了解文化火灾及其生态影响，第三阶段将实地考察和航空照片分析与火灾行为建模相结合。将量化这项研究的最后阶段将评估气候变化如何加剧这些问题。这项研究最终将产生关于历史火灾状况的驱动因素、其变化程度以及对森林恢复力的影响的新知识，我们的工作将有助于确定燃料缓解和生态恢复的优先领域。确保适应性管理急需的基线能有效提高森林应对气候变化的能力。