Utilization of agricultural waste biomass to produce organic composts

Abstract

The aim of this study was to evaluate the effect of addition of pruning residue of different tree species on the quality and time of maturation of organic composts produced from cattle manure and rock powder MB-4 (rock powder – source of Ca and Mg) in an organic system of farming in the semiarid northeastern Brazil. Piles of 100 kg were constructed in a randomized experimental design with three treatments and four repetitions. The organic composts produced were tested in a randomized design in a greenhouse using the corn plant as an indicator of nutrient accumulation. The organic compost produced by the mixture of pruning residue of mesquite, cattle manure and MB-4 had the lowest time of maturity reaching C/N ratio = 11,1 at 60 days and the highest total contents of N, P, K, Ca and Mg, 16.25, 4.43, 8.5, 15.25 and 6.0 g kg^-1, respectively. The highest accumulations of N, P, K, Ca and Mg in the corn plant were observed in the plots fertilized with compost produced from the mixture of mango pruning, cattle manure and MB-4.