Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
Abstract
The physical and chemical changes that accompany permafrost thaw directly influence the microbial communities that mediate the decomposition of formerly frozen organic matter, leading to uncertainty in permafrost–climate feedbacks. Although changes to microbial metabolism and community structure are documented following thaw, the generality of post-thaw assembly patterns across permafrost soils of the world remains uncertain, limiting our ability to predict biogeochemistry and microbial community responses to climate change. Based on our review of the Arctic microbiome, permafrost microbiology, and community ecology, we propose that Assembly Theory provides a framework to better understand thaw-mediated microbiome changes and the implications for community function and climate feedbacks. This framework posits that the prevalence of deterministic or stochastic processes indicates whether the community is well-suited to thrive in changing environmental conditions. We predict that on a short timescale and following high-disturbance thaw (e.g., thermokarst), stochasticity dominates post-thaw microbiome assembly, suggesting that functional predictions will be aided by detailed information about the microbiome. At a longer timescale and lower-intensity disturbance (e.g., active layer deepening), deterministic processes likely dominate, making environmental parameters sufficient for predicting function. We propose that the contribution of stochastic and deterministic processes to post-thaw microbiome assembly depends on the characteristics of the thaw disturbance, as well as characteristics of the microbial community, such as the ecological and phylogenetic breadth of functional guilds, their functional redundancy, and biotic interactions. These propagate across space and time, potentially providing a means for predicting the microbial forcing of greenhouse gas feedbacks to global climate change.
Department
Soil Biogeochemistry and Microbial Ecology
Publication Date
6-20-2022
Journal Title
Global Change Biology
Publisher
Wiley
Digital Object Identifier (DOI)
Document Type
Article
Recommended Citation
Ernakovich, J. G., Barbato, R. A., Rich, V. I., Schädel, C., Hewitt, R. E., Doherty, S. J., Whalen, E. D., Abbott, B. W., Barta, J., Biasi, C., Chabot, C. L., Hultman, J., Knoblauch, C., Vetter, M. C. Y., Leewis, M-C, Liebner, S., Mackelprang, R., Onstott, T. C., Richter, A. … Winkel, M. (2022). Microbiome assembly in thawing permafrost and its feedbacks to climate. Global Change Biology, 28, 5007–5026. https://doi.org/10.1111/gcb.16231
Rights
© 2022 Her Majesty the Queen in Right of Canada.
Comments
This is an open access article published by Wiley in Global Change Biology in 2022, available online: https://dx.doi.org/10.1111/gcb.16231