Chronic N and nutrient deposition impact on diversity and abundance of bacteria, fungi, and CH4 cycling prokaryotes at a northern peat bog

Abstract

Anthropogenic N deposition may threaten peatland carbon storage capabilities. Increased deposition has been associated with plant community shifts and increased decomposition rates, potentially via the disruption of natural microbial communities. By examining peat soils from randomized, replicated treatment plots in a long-term simulated chronic nitrogen deposition experiment at the Mer Bleue Bog, my objective was to characterize how increased deposition impacts diversity and abundance of broad groups of microbial decomposers, and specific CH4 cycling prokaryotes. Using fingerprinting approaches and qPCR of SSU rRNA and other functional genes, my data show that with increasing nutrient loading the bacterial and fungal community structure changed. Along the same gradient methanogen abundance decreased, however there were no corresponding changes in methanotroph community structure or abundance. My results provide new insight on the possible causes of higher CO2 and CH4 effluxes seen in situ following chronic nutrient loading.