Método da hidrólise ácida na disponibilidade de nitrogênio em resíduos orgânicos

Abstract

The nitrogen (N) available for plants from organic residues is usually estimated by greenhouse or aerobic incubation experiments. These methods are laborious, expensive and impracticable for laboratory routines, requiring alternative approaches. The aim of this work was to evaluate the acid hydrolysis as an alternative method in comparison to the N absorbed by maize on the greenhouse experiment for 10 organic wastes. The acid hydrolysis fractionated the N of the wastes’ organic matter of in labile and recalcitrant pools, which was compared to the amount of N absorbed by the plants measured by nitrogen recuperation index (NRI). The data were submitted to ANOVA and the means compared by the Tukey test (P<0.05). The relation between the methods was estimated by linear regression (p>0.05). There was a significant relationship between the labile pools and the NRI values for the coffee silverskin, chicken and cattle manure, expired coffee powder, peat and poultry litter wastes