Effect of carnauba bagana on microbiological attributes, moisture and temperature of soil

Abstract

The waste resulting from the extraction of wax from the carnauba leaf, known as carnauba bagana, is occasionally used as organic fertilizer, but little is known about the best way of application and its relationship with mineral fertilizer. The objective of this work was to verify the effect of surface application and incorporation of carnauba bagana associated with NPK fertilization on microbiological attributes, temperature and soil moisture. The experimental design was a randomized block consisting of six treatments and four replications for planting corn (Zea mays). The treatments were: a) superficial application of 8 Mg ha-1 carnauba bagana; b) incorporation of 8 Mg ha-1 carnauba bagana; c) surface application of 8 Mg ha-1 carnauba bagana + NPK, d) incorporation of 8 Mg ha-1 carnauba bagana + NPK, e) NPK application and, e) control where no fertilization occurred. Soil samples were collected from the plots, after corn harvest, to evaluate the microbial biomass carbon (MBC); basal respiration (BR); microbial quotient (qMIC), metabolic quotient (qCO2) and total organic carbon (TOC). During the experiment, soil samples were collected to determine moisture and temperature. The treatments that received the addition of carnauba bagana indicate a greater increase in TOC. The application of carnauba bagana on the surface associated with NPK fertilization contributed to the increase of the averages of MBC and qMIC. The treatments with incorporation of 8 Mg ha-1 of carnauba bagana and control showed a higher metabolic quotient. The carnauba bagana applied to the soil surface contributed to the maintenance of higher moisture and lower temperature in the soil. Through multivariate analysis, it was possible to verify that the use of carnauba bagana on the surface alone or associated with NPK showed the best results in relation to microbial carbon, organic carbon and soil moisture.