GHG fluxes from European croplands are the least well quantified and most uncertain of all fluxes. Whilst some studies have suggested a net loss of carbon from European croplands, predominantly as a soil C loss, other studies have suggested that croplands are currently close to equilibrium. In addition to CO2 emitted by SOC decomposition, agricultural soils emit N2O by nitrification and denitrification of mineral nitrogen, predominantly driven by fertilizer inputs. The uncertainty arise from the human activities like management and land use/cover change and how they influence NBP and soil organic carbon. The session will focus on the current stand of knowledge and discuss the remaining uncertainties.