Nitrous oxide (N2O) is a dangerous greenhouse gas, warms the climate and destroys the stratospheric ozone layer. Nitrous oxide is the intermediate and by-product of several processes of the nitrogen cycle conducted by soil microbes. While undisturbed wet peatlands do not emit much N2O, drained peatlands are substantial sources of nitrous oxide. A global study of peatlands led by geographers and microbiologists of the University of Tartu, Estonia, identified the microbes involved in nitrous oxide emissions from different peatland environments.