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: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=741254
• 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.

常年冻结的土壤或岩石(永久冻土)是北方生态系统的重要组成部分，改变了当地的水文、植被和野生动物的使用。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。富含冰的永久冻土的融化可能会导致基础设施遭到结构性破坏，并通过下沉和水文变化导致现有生态系统的退化。最近一个令人担忧的问题是，储存在北极永久冻土中的温室气体可能会释放，但也会在常年冰冻的亚北极区泥炭地释放。在加拿大北部，泥炭地永久冻土预计将在下个世纪在该国南部的大部分地区融化。这可能会将大量碳转移到大气中，并影响当地的生态系统，但最近的几项研究表明，泥炭地永久冻土可能比最初预期的更不容易受到气候变化的影响。因此，关于加拿大未来可能如何以及在哪里发生永久冻土融化，以及最终这将对区域产生多大影响，存在着相当大的争论。在沿海的拉布拉多，泥炭地永久冻土沿着1000公里的整个海岸线呈丛状分布。然而，缺乏对拉布拉多永久冻土的先前研究意味着，这些独特的环境在该地貌上的丰富性及其对未来变暖的脆弱性在很大程度上是未知的。该提案旨在确定拉布拉多沿海泥炭地永久冻土的分布特征，并评估气候和其他生态系统改良剂可能对受永久冻土影响的泥炭地造成的历史和未来变化。这项研究计划将结合广泛的野外数据收集、气候监测、遥感分析和数值模拟，以增强我们对泥炭地永久冻土对未来变暖的敏感性的理解。它还将量化目前储存在该区域冻结泥炭地中的碳量，从而有助于全球碳循环清点。在当地范围内，在两个社区的住房和基础设施附近发现了泥炭地永久冻土环境，预计这些环境将出现在为该地区提议的北部潜在道路路线上。泥炭地永久冻土环境对拉布拉多沿海的土著和非土著人民在当地也很重要，因为它们通常用于狩猎、诱捕和采摘浆果。后者包括具有文化价值的云莓(在因努基特语中为‘apik’)，在永久冻土丘上盛产，但在永久冻土融化后形成的较潮湿的凹地中很少发现。因此，这些泥炭地永久冻土分布的变化可能会对人类的觅食潜力和当地的野生动物产生影响。通过执行这一研究计划，所获得的知识将有助于当地生态完整性和环境评估，并有助于国家和国际上量化永久冻土融化和碳储量的努力。