Fig. 3

Effect of treatment on WEOC during the incubation of sandy soils amended with cow manure (M), biochar (B) and B–M mixtures over 56 days. Same letter(s) above the bars indicate no significant difference between treatments at p = 0.05. Vertical bars represent standard error of the mean (n = 3). M0, M13 and M26 are M rates at 0, 13 and 26 tons ha⁻¹ respectively. B0, B20 and B40 are B rates at 0, 20 and 40 tons ha⁻¹, respectively