It’s no laughing matter: draining natural peatlands such as fens, swamps and bogs for cultivation markedly increases nitrous oxide emissions. Also known as laughing gas, nitrous oxide is a powerful greenhouse gas and agent of ozone layer destruction.

The influence of warm, drained fertile soils on climate change was tested in a global survey of in situ nitrous oxide fluxes from organic soils. These data were combined with ancillary measurements of key drivers, to derive a model of nitrous oxide emissions applicable to a wide range of ecosystems and environmental conditions. Emissions from organic soils were observed to increase with rising soil nitrate levels and with rising soil temperature.

Emissions followed a bell-shaped distribution peaking at intermediate soil moisture content around 50 percent. Both nitrate and soil moisture together explains 72 percent of nitrous oxide emissions from the global organic soils.

The research, which is published in Nature Communications, shows that artificial drainage will be the primary driver of future changes in the release of this greenhouse gas from organic soils.

The study was conducted by scientists from the University of Tartu, Estonia and the University of Birmingham, UK.

Site-mean nitrous oxide fluxes by study region superimposed on a global organic-soil map. Source: Nature Communications