Compared to the sandy site, the silty site was characterized by a higher content of fine particles (clay- and silt-size particles) which implies a better soil fertility status. This is highlighted by a higher cationic exchange capacity (CEC in cmolc/kg) which can partly explain the higher bioavailability of nutrients. The silty site was also characterized by higher pH (lower soil acidity). The soil physico-chemical properties of the sandy site largely differs given the higher content of sand-size particles, which are responsible for a lower CEC and bioavailability of nutrients.
The sand site showed nitrogen (Ntot) and carbon (Ctot) to be higher under organic farming system, while the other variables remained stable. The silt site, however, showed stronger farming system effect than in the sand site. Results identify phosphorus (P), calcium (Ca) and pH to be higher under organic farming, while potassium (K), magnesium (Mg) and CEC showed to be higher under conventional farming system.