Microbial Community Patterns Reveal Differences From Bogs To Intermediate Fens In North American Peatlands Along A Latitudinal Grandient

Peatlands are unique areas of study due to their capacity to act as both carbon sinks and sources. These wetlands are estimated to hold up to one-third of the Earth’s terrestrial carbon due to an unequal relationship between microbial decomposition and biological productivity, resulting in the large accumulation of peat. However, as reservoirs, peatlands are major contributors of atmospheric carbon such as carbon dioxide (CO2) and the potent greenhouse gas, methane (CH4). For bacterial communities, Proteobacteria, Acidobacteria, and Actinobacteria were the dominate phyla on average for all peatland classes. Intermediate and rich fens experienced greater diversity and taxonomic richness when compared to bogs and poor fens. Groups such as Bacteroidetes were observed in higher abundance in the less acidic and more nutrient rich sites, potentially aiding the higher carbon turnover rates seen in these peatlands. Supporting previous findings, archaeal sequences increased with depth for nearly all sites.NMDS Bray-Curtis-dissimilarity ordinations and biplots exposed pH to be the principal influence on microbial community structuring. Predictive metagenome content (PICRUSt) showed increased microbial activity, such as amino-acid and purine/pyrimidine metabolism, in relative mid-latitude peatlands from 37 to 43 degrees North, proposing a shift towards utilization of microbial biomass in these microbial communities.