Abstract
The agricultural and agroindustrial sector are great waste generator, among them the filter cake, derived from the processing of sugarcane biomass. The inappropriate disposal of this residue can cause large impacts to the environment, however using it as an additional source of nutrients for the soil and consequently for the agricultural crops presents itself as a sustainable alternative. Therefore, the purpose of this work was to analyze the influence of the application of the filter cake, associated or not with mineral fertilization, on the chemical characteristics of the soil. The experimental design was a randomized complete block design with 4treatments and 4 repetitions: T1 - filter cake (25 ton.ha-1), T2 - filter cake (25 ton.ha-1) plus mineral fertilization(139 kg.ha-1 of formulation 04 %, 30 % and 10 % of NPK), T3 - mineral fertilization (257 kg.ha-1 of formulation 04 %, 30 % and 10 % of NPK) and T4 - control. After 90 days of treatments application the soil chemical characteristics were evaluated: V% (base saturation), CEC (cation exchange capacity), sum of bases, organic matter, carbon, macronutrients (P, K, Ca, Mg, Ca + Mg) and micronutrients (Cu, Zn, Fe, Mn and Na). Data haS been submitted to analysis of variance and the results have been compared by the Scott-Knott test at 5% level of significance. The chemical characteristics of the soil, the parameters that presented significant difference were CEC, sum of bases and Ca + Mg, with emphasis on treatments T2 and T3 for the first two parameters and T1, T2 and T3 for Ca + Mg. In this way, it was observed that the use of the filter cake in the soil, under the conditions of this experiment, presents itself as a sustainable practice. Since the disposal of this residue in soil did not cause negative changes in the evaluated parameters, as the results showed, it can be used as a source of nutrients, reducing the dependence of producers on mineral fertilizers, and consequently a more sustainable agriculture.
