SISTEMAS AGROFLORESTAIS CAFEEIRO-ARAUCÁRIA E SEU EFEITO NA MICROBIOTA DO SOLO E SEUS PROCESSOS

Abstract

The effects of agroforestry system (AFS) on soil quality have been studied. However, there is lack of information about the coffee-araucaria system, present in some environments. In order to evaluate the soil quality and its microbiota in these systems and, considering the existence of AFS coffee under two levels of shading by Araucaria (median - CSM, intense - CSI), and the growing in full sun (CSP), in the southern of Minas Gerais state, soil samples were taken from three areas in the summer of 2009 to determine the physical, chemical, and especially microbiological and biochemical attributes (density of bacteria and fungi, phosphate solubilizing, cellulolytic microorganisms, ammonifying microorganisms, denitrifying, total length of extraradical mycelium of arbuscular mycorrhizal - AM - fungi, density of fungal spores, percentage and intensity of root colonization, microbial biomass carbon, microbial activity and metabolic quotient). The coffee-araucaria agroforestry system did not affect the distribution of the microbial groups studied, but the median shading provided a greater accumulation of organic matter in the soil, with a positive effect on its physical attributes and greater mycorrhiza formation in coffee.