The past, present and future greenhouse gas (GHG) footprint of lakes: from biogeochemical processes to large scale upscaling

湖泊过去、现在和未来的温室气体 (GHG) 足迹：从生物地球化学过程到大规模升级

• 批准号: RGPIN-2022-04110
• 负责人: Prairie, Yves
• 金额: $ 3.13万
• 依托单位: Université du Québec à Montréal
• 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=765232
• 关键词: past; present; future; greenhouse; gas

The overarching goal of my NSERC Discovery Grant research program is the development a robust quantitative framework to assess the role of inland waters in landscape carbon and greenhouse gas (GHG) budgets, from local to regional to global. While CO2 is typically the dominant form in which lakes emit carbon to the atmosphere, the higher warming potential of methane (CH4) renders their impact on radiative forcing about co-equal. However, given the more complex nature of the biogeochemical cycling of methane relative to CO2, estimates of the contribution of CH4 to total GHG emissions is much more variable and poorly constrained. The specific objectives of this proposal are focused on methane and aim 1) to test a new model describing sediment CH4 production and its partitioning between ebullitive and diffusive fluxes, 2) to establish the quantitative relationship between sediment CH4 production and other lake characteristics (in particular, trophic status and temperature) on a broad set of lakes, 3) continue the development of a novel coupled physical-biogeochemical model (PB-GHG) and its validation using both a multi-lake and within-lake approaches, 4) apply the PB-GHG model to evaluate by how much the GHG footprint of Canadian lakes has changed over the past 70 years and by how much it is likely to change further under different scenarios of climate change and eutrophication. Together, these projects, combined our previous work, will provide the most comprehensive framework to better predict the dynamics of CH4 in lakes.

我的NSERC发现补助金研究计划的总体目标是开发一个强大的定量框架，以评估内陆沃茨在景观碳和温室气体（GHG）预算中的作用，从地方到区域再到全球。虽然CO2通常是湖泊向大气排放碳的主要形式，但甲烷（CH 4）较高的变暖潜力使其对辐射强迫的影响大致相等。然而，由于甲烷相对于CO2的生物地球化学循环性质更为复杂，因此对甲烷在温室气体排放总量中所占比例的估计变数更大，制约因素也更少。该提案的具体目标是以甲烷为重点，目的是：1）测试一个描述沉积物甲烷产生及其在沸腾通量和扩散通量之间分配的新模型，2）建立沉积物甲烷产生与其他湖泊特征之间的定量关系（特别是营养状况和温度）对一系列湖泊的影响，3）继续开发一个新的物理-地球化学耦合模型（PB-GHG），并使用多湖和湖内方法对其进行验证，4）应用PB-GHG模型评估加拿大湖泊的GHG足迹在过去70年中发生了多大变化，以及在气候变化和富营养化的不同情景下可能进一步发生多大变化。总之，这些项目，结合我们以前的工作，将提供最全面的框架，以更好地预测CH 4在湖泊中的动态。