The changing boreal carbon cycle at the land-water-sediment interfaces

陆地-水-沉积物界面变化的北方碳循环

• 批准号: 543661-2019
• 负责人: Lapierre, JeanFrançoisJF
• 金额: $ 5.76万
• 依托单位: Université de Montréal
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 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=765155
• 关键词: changing; boreal; carbon; cycle; land

The demand for low-carbon power is rapidly increasing across Canada due to recent developments in technologies and environmental policies that aim at reducing human impacts on the global climate. Hydro-power is perceived as a clean source of power by many Canadians, but damming carries an environmental footprint in terms of greenhouse gases emission and mercury levels that cannot be ignored, which is a hurdle for future developments in the country and exports of hydro-electricity. Moreover, this footprint depends on the underlying baseline fluxes of C and Hg that would occur even in the absence of reservoirs, but this baseline is rapidly changing in response to natural and human driven perturbations such as global warming, extremes in precipitation patterns, changes in atmospheric deposition, as well as forest fires. Full understanding of the net environmental footprint of hydro-power hence relies on two main aspects: a) accurate estimations of the fluxes of carbon and mercury in hydro-electric reservoirs over time and b) quantification of the natural fluxes of carbon and mercury at the landscape before dams were constructed. The latter is not trivial because very few estimates exist in the water-rich Canadian boreal biome and because existing estimates ignore the disproportionately important but understudied small water bodies. With the long term goal of disentangling the net effects of reservoirs on the cycling of C and Hg from shifts in natural baselines, we aim, with this project, to 1) quantify the modern and historical variation in carbon and mercury fluxes in comparison to the effect of reservoirs, 2) improve understanding of the movement and transformation of carbon from land to water across under-studied small water bodies, and 3) better understand the association between the cycling of carbon and mercury in aquatic ecosystems found in different regions across the boreal biome. To do so we will conduct field work focusing on the sampling of water and sediments of small lakes, wetlands in three regions of boreal Québec where there are major hydro-electric activity. We will further leverage existing geographic and field data to model past and future changes in the fluxes of carbon and mercury. The knowledge generated by this research will provide industries and managers with the data needed to refine the net environmental impacts of hydro-power for a better assessment of its competitiveness compared to other sources of energy as well as to hydro-power produced in other countries.

由于旨在减少人类对全球气候的影响的技术和环境政策的最新发展，对低碳力量的需求正在迅速增加。许多加拿大人认为水力动力被认为是清洁的力量来源，但是在温室气体排放和汞含量方面，该死的含量是不容忽视的环境足迹，这是该国未来发展的障碍和水力发电的出口。此外，该足迹取决于即使没有储层的情况下也会发生的C和HG的基本基线通量，但是由于自然和人类驱动的扰动，例如全球降水模式，降水模式的极端变暖，大气层的变化以及森林火灾，这种基线正在迅速变化。对水力发电的净环境足迹的全面了解依赖于两个主要方面：a）随着时间的推移，水力电源储层中碳和汞通量的准确估计以及b）在建造大坝之前在景观中的碳和汞的自然通量数量。后者并不小，因为在加拿大水上富裕的北方生物群落中，很少有估计值，并且现有的估计值忽略了不成比例的重要，但理解的小水体。长期目标是解开储层对C和HG从天然基线的转移的循环循环的净影响，我们的目标是，与该项目相比，我们的目标是量化碳和汞通量的现代和历史变化，相比之下，与储层的影响相比在整个北方生物群落的不同地区发现的水生生态系统中的碳和汞。为此，我们将进行现场工作，重点是对小湖的水和沉积物的取样，魁北克北方三个地区的湿地，那里有主要的水力发电活动。我们将进一步利用现有的地理和现场数据来建模碳和汞通量的过去和将来变化。这项研究产生的知识将为行业和经理提供所需的数据，以优化与其他国家的能源以及在其他国家生产的水力来源相比，与其他能源以及与其他能源相比，对其竞争力的净净影响进行了更好的评估。