Biological and landscape controls on the net greenhouse gas balance of High Arctic ecosystems

对高北极生态系统温室气体净平衡的生物和景观控制

• 批准号: RGPIN-2017-05921
• 负责人: Scott, Neal
• 金额: $ 1.6万
• 依托单位: Queen's University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=754825
• 关键词: Biological; landscape; controls; net; greenhouse

Since the 1950's, annual air temperatures over Arctic landmasses have risen between 2C and 3C, while winter temperatures have increased as much as 4C. These warmer temperatures could induce cascading changes to terrestrial Arctic ecosystems, such as: altered hydrological cycles from increasing precipitation, shifting distribution of plant communities, altered surface properties such as decreased surface albedo, and increased permafrost thawing. Permafrost soils contain approximately half of the global soil carbon reservoir, so an increased rate of carbon loss due to permafrost thawing could accelerate future climate change. At the same time, permafrost thawing could liberate plant nutrients, increasing plant productivity and carbon storage, creating a negative feedback on future warming. To predict the future response of arctic ecosystems to changes in climate, we need to understand key greenhouse gas (GHG) cycling processes in high Arctic ecosystems at a range of spatial and temporal scales.At the Cape Bounty Arctic Watershed Observatory (CBAWO) on Melville Island, I will explore how the interactions between vegetation distribution and climate change alters the net GHG balance of high Arctic ecosystems. Specifically, I will examine 1) the contribution of mosses to net GHG fluxes, and the interaction between mosses and soil moisture 2) the contribution of polar semi-desert communities to the net methane balance of the high Arctic, and 3) how temperature, moisture, active layer depth, solar radiation, and satellite-based estimates of vegetation properties interact to control the net GHG balance across Arctic landscapes. I will explore these questions using a combination of field and laboratory measurements, including state-of-the-art automated chambers to measure carbon dioxide fluxes at high temporal frequencies and soil molecular techniques to characterize the bacteria responsible for methane production and consumption. My results, along with those of my colleagues working at this site, will be integrated into a state-of-the art watershed scale biogeochemistry model that will provide insights into how the region might change in the future in response to changes in climate. My research will help train the next generation of Arctic scientists by providing interdisciplinary training to 4 MSc, 1 PhD, and 5 undergraduate students - the training also provides key skills for many environmental positions. Results from my research will provide insights into how terrestrial ecosystems will respond to climate change, and help develop improved models that predict the contribution of Arctic ecosystems to future climate.

自1950年代以来，北极陆地的年度气温在2C至3C之间上升，而冬季温度升高高达4C。这些较高的温度可能会引起陆地北极生态系统的层叠变化，例如：由于增加降水量增加，植物群落的分布转移，表面性能降低（例如降低表面反挡膜）以及长期冻结的融化而改变了水文周期。多年冻土土壤大约含有全球土壤碳储层的一半，因此由于冻结的永久冻结而导致的碳损失率增加可能会加速未来的气候变化。同时，永久冻结可以解放植物营养，提高植物生产力和碳储存，从而对未来的变暖产生负面反馈。为了预测北极生态系统对气候变化的未来反应，我们需要了解高北极生态系统中的重要温室气体（GHG）自行车过程，在一系列的空间和时间尺度上。生态系统。具体而言，我将检查1）苔藓对净温g通量的贡献，以及苔藓与土壤水分之间的相互作用2）极地半静脉群落对高北极的净甲烷平衡的贡献以及温度，水分，水分，水分，活跃的层深度，显着辐射，太阳辐射以及基于卫星的基于基于蔬菜的估计，以控制素食均衡。我将使用现场测量和实验室测量的结合（包括最先进的自动化室）来探讨这些问题，以测量高时间频率和土壤分子技术的二氧化碳通量，以表征负责甲烷生产和消耗的细菌。我的结果以及我在该站点工作的同事的结果将集成到最先进的流域生物地球化学模型中，该模型将提供有关该地区对气候变化的响应方式的见解。 我的研究将通过为4台MSC，1位博士学位和5名本科生提供跨学科培训来帮助培训下一代北极科学家 - 该培训还为许多环境职位提供了关键技能。 我的研究结果将提供有关陆地生态系统将如何应对气候变化的见解，并帮助开发改进的模型，以预测北极生态系统对未来气候的贡献。