Coastal Labrador peatland permafrost inventory

Northern peatlands cover approximately four million km², and about half of these peatlands are estimated to contain permafrost and periglacial landforms, like palsas and peat plateaus. Peatland permafrost environments are known to be sensitive to climate warming and ecosystem modifications, so understanding the distribution of these ice-rich landforms is important for predicting thermokarst potential, hydrological and vegetation change, and carbon cycling activities. We applied a multi-stage consensus-based approach to develop a first inventory of peatland permafrost complexes in Labrador, spanning from 51 to 61°N, with a focus on the area within 100 km of the Labrador Sea and Gulf of St. Lawrence coastline. A team of three mappers identified a total of 2092 prospective peatland permafrost complexes in coastal Labrador and adjacent parts of Quebec using high-resolution satellite imagery available via Esri ArcGIS Online (Maxar Vivid imagery, 0.5 m spatial resolution, 5 m spatial accuracy, imagery acquisition dates 2010-2020) (Esri, 2022). Each prospective peatland permafrost complex was subsequently reviewed by two of the three mappers into classes of likely, possible, and unlikely peatland permafrost complexes. Prospective complexes that were evaluated by both reviewers as containing peatland permafrost were classified as likely peatland permafrost complexes, while prospective complexes with conflicting evaluations were classified as possible peatland permafrost complexes. Interpretation of peatland permafrost presence or absence was supported by field and imagery-based validation efforts at 557 prospective peatland permafrost locations, 331 of which contained peatland permafrost. Out of 2092 initial wetland complexes, 1120 were interpreted as likely containing peatland permafrost, and 186 were interpreted as possibly containing peatland permafrost. Likely peatland permafrost complexes were mostly found in lowlands within 22 km of the coastline, in locations with corresponding mean annual air temperatures of up to +1.2 °C (1980-2010). These inventory results provide an important baseline for future mapping, modelling, and climate change adaptation strategy development for the region. Updated versions of the inventory will continue to be made available. Esri. (2023). World Imagery, https://www.arcgis.com/home/item.html?id=10df2279f9684e4a9f6a7f08febac2a9. Accessed from September 2020 to June 2023.

北方泥炭地覆盖约四百万平方公里，其中大约一半的泥炭地含有永久冻土和冰缘地貌，例如泥炭藓丘和泥炭高原。泥炭地永久冻土环境对气候变暖和生态系统变化敏感，因此，了解这些富含冰的土地形态的分布对于预测热融滑坡潜力、水文和植被变化，以及碳循环活动至关重要。本研究采用基于多阶段共识的方法，首次对拉布拉多地区51至61°N范围内的泥炭地永久冻土复合体进行了编制，重点关注拉布拉多海和圣劳伦斯湾海岸线100公里范围内的区域。由三名测绘员组成的团队利用通过Esri ArcGIS Online（Maxar Vivid影像，空间分辨率为0.5米，空间精度为5米，影像获取日期为2010-2020年）提供的高分辨率卫星影像，在拉布拉多沿海地区及其相邻的魁北克省发现了2092个潜在的泥炭地永久冻土复合体。随后，三名测绘员中的两位对每个潜在的泥炭地永久冻土复合体进行了分类，分为可能、可能和不可能的泥炭地永久冻土复合体类别。经两位评审员评估含有泥炭地永久冻土的潜在复合体被归类为可能的泥炭地永久冻土复合体，而评估意见冲突的潜在复合体则被归类为可能的泥炭地永久冻土复合体。对泥炭地永久冻土的有无进行解读时，得到了557个潜在的泥炭地永久冻土地点的现场和影像验证努力的支持，其中331个地点含有泥炭地永久冻土。在2092个初始湿地复合体中，1120个被解读为可能含有泥炭地永久冻土，186个被解读为可能含有泥炭地永久冻土。可能的泥炭地永久冻土复合体主要分布在距离海岸线22公里内的低地，在这些地点，相应的年均气温最高可达+1.2°C（1980-2010年）。这些编制结果为该区域未来的制图、建模和气候变化适应策略的开发提供了重要的基础。库存的更新版本将继续提供。Esri.（2023）. World Imagery，https://www.arcgis.com/home/item.html?id=10df2279f9684e4a9f6a7f08febac2a9。访问日期：2020年9月至2023年6月。