ABSTRACT The objective of this study was to evaluate the quality of the percolate in soil columns cultivated with Tiffon-grass 85 under different wastewater rates from swine slaughterhouse and dairy. The experiment was conducted at the Department of Engineering at the Federal University of Lavras, in PVC columns with 0.30 m of diameter and 1.2 m deep, filled with Dark Red Latosol cultivated with Tifton-grass 85. The treatments consisted of a (AQT0) control with recommended chemical fertilization for Tifton-grass 85 (300 kg ha-1 year-1 of N), and four doses of SSW and DPW (100, 200, 300 and 400% of the recommendation) in a CRD with 3 replications. The samples of percolated were collected and characterized weekly. The treatments of highest dosage have obtained COD, after 120 days, of 47.7 mg L-1 (AAT3) and 38.6 mg L-1 (AAT4). Although nitrate concentrations were elevated on the earlier months, the greater assimilation of nutrients by the Tifton-grass 85 and the reduction of the mineralization of organic material resulted in lower nitrate concentrations of 10 mg L-1.

ABSTRACT The aim of this study was to evaluate the soil chemical properties submitted to fertigation with slaughterhouse (SW) and dairies (DW) wastewater. The experiment was conducted in the Environmental Engineering Center and Sanitary of UFLA/MG in PVC columns filled with Dark Red Latosol (Oxisol) and randomly distributed. The treatments applied with nitrogen based load (300 kg ha years-1 of N) consisted of four doses of SW and DW (100, 200, 300 and 400% of the recommendation) and AQT0 control at random. The soil was collected at a depth of 0.30 m and, subsequently, characterized in terms of physical, chemical and physicochemical. The application of treatment of the largest irrigation of DW provided, after 120 days of monitoring, N concentration of 1.85 g kg-1. However, the treatment with AQT0 obtained N concentration of 0.81 g kg-1, in the soil. We observed that the largest irrigation of SW provided increases of 2.62 and 5.49 g kg-1, respectively, in the P and K concentrations of the soil. There was quadratic increase in the N concentration in the 0.30 m soil depth of the columns with the increase in the applied irrigations of SW and DW, being obtained maximum values of 1.85 and 1.02 g kg-1 that were obtained in the relative irrigation of the application dose of 600 kg ha-1 of N.