Functional microbial ecology in arctic soils: the need for a year-round perspective

Abstract

The microbial ecology of arctic and sub-arctic soils is an important aspect of the global carbon cycle, due to the sensitivity of the large soil carbon stocks to ongoing climate warming. These regions are characterised by strong climatic seasonality, but the emphasis of most studies on the short vegetation growing season could potentially limit our ability to predict year-round ecosystem functions. We compiled a database of studies from arctic, subarctic, and boreal environments that include sampling of microbial community and functions outside the growing season. We found that for studies comparing across seasons, in most environments, microbial biomass and community composition vary intra-annually, with the spring thaw period often identified by researchers as the most dynamic time of year. This seasonality of microbial communities will have consequences for predictions of ecosystem function under climate change if it results in: seasonality in process kinetics of microbe-mediated functions; intra-annual variation in the importance of different (a)biotic drivers; and/or potential temporal asynchrony between climate change-related perturbations and their corresponding effects. Future research should focus on 1) sampling throughout the entire year; 2) linking these multi-season measures of microbial community composition with corresponding functional or physiological measurements to elucidate the temporal dynamics of the links between them; and 3) identifying dominant biotic and abiotic drivers of intra-annual variation in different ecological contexts.

Seasonal variation in near-surface seasonally thawed active layer and permafrost soil microbial communities

“…But despite evidence that Arctic soil microbial communities show seasonal variation in composition and abundance [22], our understanding of this variation remains limited, due in part to the relative difficulty of sampling from cold environments outside of summer. Indeed, a recent review of seasonality in Arctic soil microbial ecology [23] identifies an ongoing and pressing need to identify the dominant drivers of seasonality in Arctic soil microbial community composition, and to identify linkages with biogeochemical processes.…”

Genome analysis and description of Tunturibacter gen. nov. expands the diversity of Terriglobia in tundra soils

“…Approximately one third of the global soil carbon stock is stored in Arctic soils (Hugelius et al, 2014; Loya & Grogan, 2004), and despite sub‐zero temperatures, microbial activity persists throughout the long winters, albeit at a slower rate (Gadkari et al, 2020; Natali et al, 2014; Nikrad et al, 2016; Oechel et al, 1997; Pessi et al, 2022; Poppeliers et al, 2022; Welker et al, 2000). Microbes play important roles in nutrient cycling as they decompose soil organic matter (SOM).…”

Carbon Emission and Biodiversity of Arctic Soil Microbial Communities of the Novaya Zemlya and Franz Josef Land Archipelagos

“…The relationship between biodiversity and soil ecosystem functioning in the Barents Sea archipelagos is poorly understood. More information is available on the soil communities of the Spitsbergen archipelago [ 18 , 19 , 20 , 21 ], but the Franz Josef Land and Novaya Zemlya archipelagos, located to the east and less exposed to the Atlantic Ocean, are much less studied [ 11 , 13 ]. In order to investigate the relationship between the soil carbon dioxide emission process and soil microbial diversity, we conducted a study of soil samples from the Novaya Zemlya and Franz Josef Land archipelagos, in which we analyzed bacterial diversity, soil parameters and soil carbon dioxide emission.…”