Conventional technology is virtually unable to measure complete GHG budgets of drained organic soils, which may provide misleading results. So, global estimates of GHG emissions are based on coarse assumptions that don’t take into account the complexity of agroecosystems. Better data are needed for evidence-based rulings on mitigation. By newly developed Relaxed Eddy Accumulation (REA) systems we will study complete, continuous GHG budgets (H2O, CO2, CH4, N2O, NH3) from 3 pairs of organic agricultural fields with contrasting peat layer depth and cultivation. This will shed new light on the climate impact of cultivated organic soils and the importance of site-specific conditions and management. High time resolution enables process studies to reveal key parameters and mechanisms that control GHG fluxes in the soil-plant-atmosphere system, which will significantly improve simulation models. This will notably improve GHG reporting, climate modeling, and the base for mitigation strategies.