Análise microbiológica dos diferentes meios de suporte de uma estação de tratamento de efluentes por zona de raízes de fluxo vertical

Abstract

The Sewage Treatment Plant - WTP root zone is a constructed wetland, composed of substrtate and with vegetation on its surface. Next plant roots is the adhesion of microorganisms forming a biofilm that aids in the clearance of sewage, and is occurring in this region associations and important reactions, which gives the name of the system as the root zone. The objective of this study was to estimate the density of microorganisms from a treatment plant for the root zone at different media support: the root zone, gravel and sand, to understand the dynamics of microorganisms in the system. The results of the analysis of plate count for fungi and heterotrophic bacteria showed differences in the density of these organisms in different media support. The most probable number method indicated little variation for E. coli and total coliforms. The results for bacteria sulforedutoras varied only in a collection featuring low densities, the nitrate-reducing bacteria also showed low values in relation to the denitrifying bacteria. Fungi and heterotrophic bacteria were found in greater density in the middle of the root zone support, and denitrifying bacteria, sulforedutoras, total coliforms and Escherichia coli did not show significant variations with respect to their density in different media support, varying similarly and regulate the same. The nitratereducing bacteria varied the density of irregular shape in the different means of support, indicating that probably is the ratio of oxygen that induces this variation.