“…Although Na + concentrations in sugarcane vinasse are relatively low (50-325 mg L −1 -; Lyra et al, 2003;Mariano et al, 2009;Ferreira et al, 2011;Rolim et al, 2013) compared to other ions, e.g., potassium (1200-4600 mg L −1 -; Prada et al, 1998) and sulfates (600-3730 mg L −1 -; Ferreira et al, 2011;Prada et al, 1998), the inputs of Na + ions could result in concentrations of approximately 1800-3400 mg L −1 when using NaHCO 3 as the alkalizing compound. These values are at least 2.4-to 5.8-fold higher than the concentrations of calcium (460-740 mg L −1 ) and magnesium (210-310 mg L −1 ) commonly measured in sug-arcane vinasse (Lyra et al, 2003;Mariano et al, 2009;Ferreira et al, 2011;Rolim et al, 2013), in order to increase the risks of soil sodification. Conversely, the use of NaOH in the considered dosage (4 g g −1 COD-vinasse-Table 2) would only slightly increase Na + levels in vinasse (51.3-65.1 mg L −1 , depending on the application of phase separation), most likely leading to null risks of soil sodification when applying the biodigested vinasse into soils.…”