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

Area of Science:

• Microbial ecology
• Soil science
• Climate change research

Background:

• Arctic and sub-arctic soils store large carbon stocks sensitive to climate warming.
• Most research focuses on the growing season, potentially limiting understanding of year-round ecosystem functions.

Purpose of the Study:

• To assess the seasonal dynamics of microbial communities and functions in arctic, sub-arctic, and boreal soils.
• To identify knowledge gaps and guide future research on year-round microbial ecology in cold regions.

Main Methods:

• Compiled a database of studies including microbial sampling outside the growing season.
• Analyzed studies comparing microbial community composition and biomass across different seasons.

Main Results:

• Microbial biomass and community composition exhibit significant intra-annual variation in most studied environments.
• The spring thaw period is frequently identified as the most dynamic phase for microbial communities.
• Seasonality in microbial communities can affect process kinetics, driver importance, and temporal synchrony with climate change impacts.

Conclusions:

• Year-round microbial activity is critical for accurate predictions of carbon cycle responses to climate change.
• Future research must prioritize year-round sampling and link community composition to function.
• Identifying key biotic and abiotic drivers of seasonal microbial variation is essential for understanding ecosystem dynamics.