Fire versus water: ecosystem boundaries in tropical forest landscapes

火与水：热带森林景观中的生态系统边界

• 批准号: RGPIN-2019-05052
• 负责人: Schwartz, Naomi
• 金额: $ 2.04万
• 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: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=714552
• 关键词: Fire; versus; water; ecosystem; boundaries

Understanding the interactions between climate, disturbance, and vegetation and the ways human activities modify these relationships in tropical biomes is a major challenge with global implications. Over the next five years, my research program will identify key feedbacks between climate variability, soil properties, fire, and vegetation structure and function in seasonally dry tropical forests (SDTF). We will address the following short-term objectives: 1) Quantify the influence of climate variability and land use on fire regimes in SDTF landscapes and 2) identify key feedbacks between fire, soil conditions, and vegetation structure and function at boundaries between vegetation types. We will address these objectives with studies across multiple spatial scales, ranging from global analyses to individual leaves. Much of our work will take place in northern Cambodia, where deciduous dipterocarp forests, which resemble savanna and frequently burn, form patchy landscape mosaics and abrupt boundaries with dry evergreen forests. We will use this system as a model to understand anthropogenic and biophysical drivers of fire activity, feedbacks between fire, soil characteristics, and vegetation, and to explore relationships between plant species water-use strategies and fire sensitivity. To address Objective 1, we will use remote sensing to characterize fire regimes across all SDTF, and regionally within northern Cambodia, to explore factors that shape SDTF fire regimes. To address Objective 2, we will conduct field research to characterize variation in environment, forest structure and dynamics, and plant strategies across forest types. Measurements of functional traits related to water-use strategies and vulnerability to fire, along with data on soil characteristics and fire history will allow us to infer which environmental factors exert the strongest filters and to what degree fire favors particular water-use strategies. We will also use LiDAR to characterize forest structure, and link variation in forest structure to fire history at the landscape scale. Changes in tropical forest structure and function have large implications for carbon storage and biodiversity, but are difficult to predict, in part due to incomplete understanding of the processes that govern the boundaries between ecosystems. Global studies of forest-savanna boundaries have excluded southeast Asian ecosystems, limiting generality. By quantifying feedbacks between climate, fire, and vegetation in southeast Asian ecosystems, my research program will help resolve some of this uncertainty. Our research will have important applications for conservation and forest management, and our engagement with Cambodia's Forest Administration will ensure that our work directly affects local policy and management guidelines. The proposed research will train at least 8 HQPs, including 3 PhDs, 2 MScs, and 3 undergraduates, and will result in at least 10 peer reviewed publications.

了解气候，干扰和植被之间的相互作用以及人类活动在热带生物群落中修改这些关系的方式是全球影响的主要挑战。在接下来的五年中，我的研究计划将确定气候变异性，土壤特性，火灾和植被结构与植被结构与功能之间的关键反馈（SDTF）。我们将解决以下短期目标：1）量化气候变异性和土地利用对SDTF景观中火灾制度的影响，并确定在植被类型之间的边界处的火灾，土壤条件以及植被结构和功能之间的关键反馈。 我们将通过跨多个空间量表的研究来解决这些目标，从全球分析到单个叶子。我们的大部分工作都将在北柬埔寨进行，在那里，落叶二角果森林类似于稀树草原，经常燃烧，形成了斑驳的景观马赛克，并与干燥的常绿森林形成了突然的界限。我们将使用该系统作为模型来了解火灾活动的人为和生物物理驱动力，火灾，土壤特征和植被之间的反馈，并探索植物物种水利用策略与火灾敏感性之间的关系。 为了满足目标1，我们将使用遥感来表征所有SDTF以及北部柬埔寨范围内的区域的火灾制度，以探索塑造SDTF火灾制度的因素。为了解决目标2，我们将进行现场研究，以表征环境，森林结构和动态的变化以及跨森林类型的植物策略。与水利用策略和火灾脆弱性有关的功能性状的测量以及有关土壤特征和火灾历史的数据将使我们能够推断出哪些环境因素具有最强的过滤器，并且在多大程度上有利于特定的水利用策略。我们还将使用LiDAR来表征森林结构，并将森林结构的变化与景观量表的火灾历史联系起来。 热带森林结构和功能的变化对碳储存和生物多样性具有很大的影响，但很难预测，部分原因是对控制生态系统之间边界的过程的理解不完整。全球对森林 - 萨瓦纳边界的研究排除了东南亚生态系统，限制了一般性。通过量化东南亚生态系统中气候，火和植被之间的反馈，我的研究计划将有助于解决其中的一些不确定性。我们的研究将在保护和森林管理方面有重要的应用，我们与柬埔寨森林管理局的参与将确保我们的工作直接影响当地政策和管理指南。拟议的研究将培训至少8个HQP，包括3个博士学位，2个MSC和3名本科生，并将至少有10个同行评审的出版物。