Susceptibility of peatland permafrost in coastal Labrador to future environmental change

拉布拉多沿海泥炭地永久冻土对未来环境变化的敏感性

• 批准号: RGPIN-2020-06499
• 负责人: Way, Robert
• 金额: $ 1.82万
• 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: 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=718348
• 关键词: Susceptibility; peatland; permafrost; coastal; Labrador

Perennially frozen soil or rock (permafrost) is a critical component of northern ecosystems, altering local hydrology, vegetation and wildlife usage. Permafrost is also the only element of the terrestrial cryosphere that allows communities and infrastructure to be permanently situated on it. Thawing of ice-rich permafrost can lead to structural damage to infrastructure and degradation of current ecosystems through subsidence and hydrological changes. A recent concern is the potential release of greenhouse gases stored in permafrost in the Arctic but also in perennially frozen Subarctic peatlands. In northern Canada, it is expected that peatland permafrost will thaw in most of the southern half of the country over the next century. This could mobilize large quantities of carbon into the atmosphere and impact local ecosystems, but several recent studies showed that peatland permafrost may be less vulnerable to climate change than originally expected. Consequently, there is considerable debate as to how and where permafrost thaw may occur in Canada in the future, and ultimately how much impact this will have on a regional basis. In coastal Labrador, peatland permafrost occurs in clusters along the entirety of the >1000 km coastline. However, a lack of prior studies on permafrost in Labrador means that the abundance of these unique environments on the landscape and their vulnerability to future warming is largely unknown. This proposal aims to characterize the distribution of peatland permafrost in coastal Labrador and to assess historical and future changes to permafrost affected peatlands that could be caused by climatic and other ecosystem modifiers. This research program will combine extensive field data collection, climate monitoring, remote sensing analysis and numerical modelling to enhance our understanding of peatland permafrost susceptibility to future warming. It will also quantify carbon quantities currently stored in frozen peatlands in the region thus contributing to global carbon cycle inventorying. On a local-scale, peatland permafrost environments are found adjacent to housing and infrastructure in two communities and are expected to occur along potential road routes north proposed for the region. Peatland permafrost environments are also locally important to Indigenous and non-Indigenous Peoples in coastal Labrador because they are commonly used for hunting, trapping and berry picking. The latter includes culturally valued cloudberry (apik' in Inuktitut) which are abundant on permafrost mounds but rarely found in wetter depressions formed post permafrost thaw. Changes to the permafrost distribution in these peatlands may thus have consequences on human foraging potential and local wildlife. Through the execution of this research program knowledge gained will contribute to local ecological integrity and environmental assessment and to national and international efforts to quantify permafrost thaw and carbon stocks.

永久冻土或岩石是北方生态系统的重要组成部分，改变了当地的水文、植被和野生动物的利用。永久冻土也是陆地冰冻圈中唯一允许社区和基础设施永久位于其上的元素。富冰永久冻土的融化可能会导致基础设施的结构性破坏，并通过沉降和水文变化导致现有生态系统的退化。最近的一个担忧是，储存在北极永久冻土和常年冻结的亚北极泥炭地的温室气体可能会释放出来。在加拿大北部，预计下个世纪该国南部大部分地区的泥炭地永久冻土层将融化。这可能会将大量的碳排放到大气中，并影响当地的生态系统，但最近的几项研究表明，泥炭地永久冻土对气候变化的影响可能比最初预期的要小。因此，关于未来加拿大永久冻土如何以及在何处解冻，以及最终这将对区域基础产生多大影响，存在相当大的争论。