Termite mounds mitigate half of termite methane emissions

Significance Termites are important decomposers of plant material in tropical ecosystems, and thereby produce globally significant amounts of the greenhouse gas CH 4 . Here, we provide a mechanistic understanding of CH 4 turnover in termite mounds to fill a long-standing knowledge gap. Using field measurements, we show that termite mounds oxidize, on average, half of the CH 4 produced by termites before emission. This “hidden” biofilter mechanism is mediated by methanotrophic bacteria living in the mound walls or the soil beneath, for which internal termite-mound structures can facilitate CH 4 transport. Process links within the mound stabilize the filter efficiency. Moreover, we estimate undisturbed termite biomass via CH 4 emissions. This knowledge is crucial to reduce uncertainty in global termite-derived CH 4 emissions.