Key Findings
Understanding the factors that influence microbial communities during permafrost thaw can help scientists predict climate change impacts. UNH researchers discovered environmental factors are less important in structuring permafrost bacterial communities prior to thaw, and that understanding the impact of chance is essential for predicting post-thaw community structure and function.
About the Co-Author
Jessica Ernakovich, Assistant Professor of Natural Resources and the Environment
Contact information: Jessica.Ernakovich@UNH.edu, 603-862-2216, Ernakovich Lab website
This research first published in Frontiers in Microbiology.
Researchers: S. Doherty, R. Barbato, A. Grandy, W. Kelley Thomas, S. Monteux, E. Dorrepaal, M. Johansson, and J. Ernakovich
NASA warns that the Northeast faces increasing challenges due to climate change, including heat waves, heavy downpours, and sea level rise. Such outcomes could be influenced by changes to microbial communities in the Arctic resulting from the thawing of permafrost and its impact on greenhouse gas production. Scientists at the University of New Hampshire are studying the ecological factors that affect microbial communities in order to predict the implications of a thawing Arctic.
Former graduate student Stacey Doherty, who conducted research supported by the New Hampshire Agricultural Experiment Station, explains that thaw-induced environmental changes result in altered microbial communities and their functions, which include greenhouse gas production. “The Northern high latitudes are warming twice as fast as the global average, and permafrost— soil frozen for two or more years—has become vulnerable to thaw. Thaw-induced environmental changes result in altered microbial communities and the functions they carry out, which includes the production of greenhouse gases,” she said. These ecological factors influence the identity and abundance of microbial communities during permafrost thaw, including measurable factors such as pH, salinity, and temperature, as well as non-measurable factors such as chance genetic mutation, lineage loss, and dispersal. "Understanding both non-random and random factors may improve predictions of greenhouse gas loss from thawing permafrost landscapes,” Doherty added.
"Understanding both non-random and random factors may improve predictions of greenhouse gas loss from thawing permafrost landscapes."
Doherty's research found that microbial communities were structured less by environmental factors than anticipated, with environmentally driven processes becoming more significant as the thaw progressed. Going forward, Doherty and her collaborators aim to understand how ecological factors shape microbial communities and their function, with the hope of predicting functional outcomes after permafrost thaw.
The results of Doherty's research are particularly relevant to New England due to the rapid global circulation of heat-trapping gases produced at the poles, which increase the greenhouse effect at lower latitudes. While functions that are shared by many microbial species are less likely to be affected by randomness, more work is needed to understand the relationship between these factors and functions for those performed by a narrower subset of species. Ultimately, predicting which microbes are present after permafrost thaw is essential for understanding the processes being carried out and the amount of greenhouse gas released.
This study was funded by the NH Agricultural Experiment Station.
