Peatlands are a type of wetland which store more organic carbon than any other type of land ecosystem in the world.
Due to waterlogged conditions, dead plant materials do not fully decay and carbon accumulates in peatlands over thousands of years.
Therefore, natural peatlands help to cool the climate by capturing carbon dioxide (CO2) from the atmosphere through photosynthesis and trapping carbon in soils.
However, artificial drainage of peatlands for agriculture aerates the soil and enhances the decay of organic matter, rapidly releasing carbon into the atmosphere.
Peatlands are a missing piece of the carbon cycle puzzle; little is known about how much carbon has been released due to drainage and conversion of peatland to cropland during the historical sprawl of agriculture, and about the role of cultivated peatlands versus natural peatlands.
The new international study, led by INRAE and LSCE, and including the University of Exeter, quantified CO2 fluxes in natural and cultivated peatlands between 850 and 2010.
The study provides the first detailed estimates of historical carbon losses from cultivated northern peatlands.
“We incorporated peatland hydrological and carbon processes into a process-based land surface model," said Chunjing Qiu who developed the model and designed the study, and worked at the Institut National de de recherche pour l'agriculture, l'alimentation et l'environnement (INRAE) and the Laboratory for Sciences of Climate and Environment (LSCE) in France.