Landfill cover soil column experiment

In this study, soil columns simulating MSW landfill hotspots were constructed using cover soil from a former MSW landfill site and hydrated with cyclic synthetic precipitation events. The aim was to delineate the effects of soil moisture dynamics on CH4 consumption, with the hypothesis that precipitation would gradually decrease CH4 consumption rates as soil moisture increased. Changes in gas cycling were not reflected in the soil microbial communities, which were dominated by methanotrophic lineages, and which remained essentially unchanged over the course of the experiment. These findings are consistent with other studies of soil moisture effects on landfill CH4 consumption and support the need for soil moisture considerations in MSW landfill mitigation plans, particularly for those located in regions with high and variable precipitation which could exacerbate CH4 emissions.