Fig. 2: System-level effects of soil tillage and C-friendly practices on cropping system performance (SOC storage, GHG emissions, pesticide use), accounting for interactions and synergies among practices rather than isolated effects.

C-friendly practices increase the quantity and diversity of organic C inputs, which is recognised as the most efficient way to increase SOC storage. They can also reduce GHG emissions by replacing mineral N inputs with biological N fixation and organic amendments. The signs + and – relate to the effect of soil tillage on the considered impact. The direct effect of soil tillage on SOC storage is uncertain, but is generally small or even negligible when considering the entire soil profile. However, frequent tillage can indirectly affect SOC storage by reducing the growth period of crops, particularly cover crops. No-till farming reduces GHG emissions linked to fossil fuel combustion, but these emissions generally account for only a small part of total GHG emissions from cropping systems. Furthermore, reducing soil tillage has contrasting effects on N₂O emissions, depending on the context. Therefore, the overall effect of tillage on total GHG emissions is particularly uncertain. No-till systems generally require more pesticides, particularly herbicides. Soil tillage is a strategic tool to reduce pesticide dependency.