Atividade microbiana e propriedades bioquímicas do solo sob a adição de composto orgânico e palha de café

Abstract

The use of organic residues, in modern agriculture, and the adoption of more sustainable management practices, is seen as an important choice, mainly because this material is recyclable in the soil. This study was done with Oxisol soil samples, with four replications, collected from the 0-5 cm layer, to which 0, 10, 20, 40 or 80 g kg-1 of organic-mineral compost (OMC), or 0, 7, 14, 28 or 56 g kg-1 of coffee beans trash (CBS) was added. Chemical analyzes were performed to characterize soil and organic residues used. The evaluated attributes were phosphorus (P) availability in the soil, soil microbial respiration (RMS), carbon (C) mineralization percentage of CBS, and activity of the enzymes: dehydrogenase (DHA), hydrolases fluorescein diacetate (FDA), β-glucosidase, invertase, urease and acid and alkaline phosphatases. The results showed that addition of OMC and CBS has important implications for soil microbial and biochemical activity. Added organic residues resulted in a significant increase in RMS, where the smallest addition of CBS (7 g kg-1) presented greater values than the greatest addition of OMC (80 g kg-1). Adding OMC resulted in a linear increase of available P. Percentage mineralization C in CBS exceeded 85%. The activity of DHA, FDA and β-glucosidase showed greater values after the addition of CBS than of OMC. The results suggest that use of organic residues, composted or natural, in agricultural production system can be an important management practice because it showed changes in soil biological and biochemical processes.