The aim of this study was to evaluate the effects of vinasse (100 and 200 m³ ha-1) on the degradation and sorption of diuron in Rhodudalf and Haplorthox soiIs. For the degradation study an experiment was carried out in a completely randomized design with a factorial experiment of 2 (soils) x 3 (vinasse: 0, 100 and 200 m³ ha-1), for 120 days. The mineralization was evaluated by radiorespirometry. At the end of the incubation, the original compounds and their metabolites were extracted from the soils and detected in the radio-scanner. Another experiment was simultaneously carried out to evaluate the effect of the vinasse doses and herbicide on the microbial activity, pH and organic carbon content of the soil. The sorption experiment was carried out under the same conditions as the degradation study, with 5 herbicide concentrations. The diuron degradation in the Rhodudalf soil was higher in the vinasse presence, but no difference was found on the Haplorthox soil. The vinasse addition increased the microbial activity and the pH. The sorption of diuron was low and not affected by vinasse.
herbicide diuron; diuron sorption; diuron degradation; vinasse