Combined impact of no-tillage and cover crops on soil carbon stocks and fluxes in maize crops

Soil plays a major role in the carbon cycle for both stocks and respiration since soil organic (SOC) is most important pool CO2 efflux largest source of emissions to atmosphere. The aim this study was understand how combination no-till (NT) cover cropping (CC) influences SOC respiration. measured southwestern France from April October at two distinct sites characterized by contrasting initial contents. Each site included adjoining maize fields which conservation (NT+CC) conventional (CT) practices were used. For with high contents (> 50 tC ha-1 0–30cm layer), 0–90 cm depth (NT+CC: 72.4 ± 10.6, CT: 68.9 9.2 t C ha-1) during growing season 0.57 0.24, 0.54 0.26 g m-2 h-1) not significantly different practices. low contents, 42.7 5.5, 29.7 4.8 0.86 0.32, 0.50 0.34 higher NT+CC than CT Due crop biomass root density, mineralization enhanced. We showed positive effect on stock upper layers but also deeper (60–90 cm) only content environment. At levels, may have reached its sequestration potential, or time implemented long enough observe effects. Our shows that potential sequester large amounts SOC, enabling mitigation greenhouse gas emissions, strongly depends