Permafrost thaw waters linked to inhibited methane production in intact palsa soil

Discontinuous permafrost areas in northern Europe are on a trajectory to nearly completely thaw by the end of the century, and will likely transition to post-thaw wetland mires and fen habitats. Our field site is located in Northern Finland (Peera palsa; 68.877961?N, 21.079261?E) was chosen for its documented chronosequence and remoteness. Peera palsa has lost 77.2 percent of its aerial mass between the years of 1959 and 2021 emphasizing the need for more field experiments in this remote, but rapidly changing landscape. To assess the C dynamics of an intact palsa as it begins to thaw, we used laboratory incubations in tandem with a metagenomic total community assay at targeted depths and experimental treatments for microbial functional potential. From both incubations (soil-horizon and mesocsom-scale) an inhibited C production effect was observed when the incubation soil material was innoculated with water from the Peera palsa thaw pond. Pairing incubation data with the metagenomic analysis will allow us to better understand the permafrost thaw sequence with a connection between the measured metabolic respiration fluxes and the communities that produced them. This experiment seeks to investigate the magnitude of influence potential inhibitors have on the green house gas flux rate of permafrost thaw. We investigate our hypothesis using experimental greenhouse gas production mesocosms coupled with metagenomic sequencing of water and soil samples.