Root oxygen loss from Raphia taedigera palms mediates greenhouse gas emissions in lowland neotropical peatlands

Aims Little is known about the influence of vegetation on the timing and quantities of greenhouse gas fluxes from lowland Neotropical peatlands to the atmosphere. To address this knowledge gap, we investigated if palm forests moderate greenhouse gas fluxes from tropical peatlands due to radial oxygen loss from roots into the peat matrix. Methods We compared the diurnal pattern of greenhouse gas fluxes from peat monoliths with and without seedlings of Raphia taedigera palm, and monitored the effect of land use change on greenhouse gas fluxes from R. taedigera palm swamps in Bocas del Toro, Panama. Results CH4 fluxes from peat monoliths with R. taedigera seedlings varied diurnally, with the greatest emissions during daytime. Radial oxygen loss from the roots of R. taedigera seedlings partially supressed CH4 emissions at midday; this suppression increased as seedlings grew. On a larger scale, removal of R. taedigera palms for agriculture increased CH4 and N2O fluxes, but decreased CO2 fluxes when compared to nearby intact palm forest. The net impact of forest clearance was a doubling of the radiative forcing. Conclusions R. taedigera palm forest influences the emission of greenhouse gases from lowland tropical peatlands through radial oxygen loss into the rhizosphere.