A Novel Laboratory-Scale Mesocosm Setup to Study Methane Emission Mitigation by Mosses and Associated Methanotrophs.

Degraded peatlands are often rewetted to prevent oxidation of the peat, which reduces CO emission. However, the created anoxic conditions will boost methane (CH) production and thus emission. Here, we show that submerged peat mosses in rewetted-submerged peatlands can reduce CH emission from peatlands with 93%. We were able to mimic the field situation in the laboratory by using a novel mesocosm set-up. By combining these with 16S rRNA gene amplicon sequencing and qPCR analysis of the and genes, we showed that submerged mosses act as a niche for CH oxidizing bacteria. The tight association between peat mosses and methane oxidizing bacteria (MOB) significantly reduces CH emissions by peatlands and can be studied in more detail in the mesocosm setup developed in this study.