Microbiological indicators of recovery soil quality in a agroforestry system

The verification of soil quality is an important tool to monitor its degradation, and to plan the implementation of sustainable management practices. The objective of this study was to evaluate soil quality in three agroforestry systems located in the Associação de Pais e Amigos dos Excepcionais (APAE RURAL) of Campo Mourão, Paraná. The three areas present distinct stages: an initial one, with characteristics of soil degradation activity (Area 1); an intermediary, where the agroforestry system was implemented a year ago (Area 2); and an advanced one, presenting more mature and perennial forest formation (Area 3). Three functional groups of microorganisms were used in each of the areas: total fungi, aerobic bacteria and cellulase producing bacteria. All microorganisms were quantified by Colony Forming Units per gram (UFC / g) of diluted soil. Area 1 showed lower abundance of total microorganisms, in the order of 105 UFC; Area 2 presented intermediate composition of total fungi, aerobic bacteria and cellulase producing bacteria, with UFC around 107 for the three functional groups; Area 3 had the highest amount of fungi (108), aerobic bacteria (1010) and cellulase producing bacteria (1011). When comparing the areas within each functional group, the lowest amount of aerobic bacteria in Area 1 (107) was observed, as well as a higher amount of cellulase producing bacteria in Area 3 (1011). These results show that the areas have distinct qualities in relation to microorganisms. Area 1 with less microorganisms, Area 2 with intermediate quantities and Area 3 with more colonies formed as expected due to the time of implantation of the agroforestry system in each area