Effects of soil warming and thermokarst on soil microbial communities in the High Canadian Arctic, 2005-2021.

Soil microbes are not only key drivers for nutrient and energy cycles, but they are also fast responders to changes in their environment- and as such act as bioindicators of climate change. The temperatures in the Arctic are warming two times faster than at lower latitudes and lead to warming of permafrost soils, an increase of the active layer and eventually to thermokarst, the thawing of permafrost. Thawing permafrost affects the hydrological systems and increases the potential of old carbon becoming available for decomposition. The fate of carbon stores will rest largely on the response of plant and microbial communities to the changed conditions. Especially the ice rich permafrost soils in the High Arctic are highly sensitive to increasing air temperatures, because the permafrost occurs close to the surface and the soils lack the insulation provided by a thick vegetation cover and organic soil horizons as found in the Low Arctic (Farquharson et al. 2019). This study examines the effects of soil warming and thermokarst on fungal and bacterial communities of active layer soils in the three most northern bioclimatic subzones (A, B, C) of the Arctic that occurred over 10 years (2005-2016). We used Illumina sequencing to analyze the fungal and bacterial communities and obtained environmental data to investigate the effect of warming and thermokarst on fungal and bacterial communities in the High Arctic. Here we present the assembled fungal, bacterial and environmental data sets.

土壤微生物不仅是养分与能量循环的核心驱动因子，同时也是环境变化的快速响应类群，因此可作为气候变化的生物指示物（bioindicators of climate change）。北极地区的升温速率是低纬度地区的两倍，由此引发永久冻土（permafrost）升温、活动层（active layer）厚度增加，最终导致热喀斯特（thermokarst）现象——即永久冻土融化。永久冻土融化会扰动水文系统，并提升老旧碳被分解利用的潜在可能性。碳库的存续状态很大程度上取决于植物与微生物群落对环境变化的响应。尤为值得注意的是，高北极地区的富冰永久冻土对气温升高极为敏感：该区域的永久冻土贴近地表，且缺乏低北极地区常见的厚植被覆盖与有机土层所提供的隔热层（Farquharson等人，2019）。本研究针对北极三大最北部生物气候亚区（A、B、C）的活动层土壤，探究了土壤增温与热喀斯特现象对真菌及细菌群落的影响，观测周期跨越2005至2016年共计10年。研究采用Illumina测序（Illumina sequencing）技术分析真菌与细菌群落，并获取环境数据以解析增温和热喀斯特对高北极地区真菌、细菌群落的调控效应。本数据集即包含组装完成的真菌、细菌及环境数据集。