ASSESMENT OF MICROBIOLOGICAL DYNAMICS AND TROPHIC STATUS INDICATORS IN A MULTI USE RESERVOIR LOCATED IN THE BRAZILIAN SEMIARID

Abstract

This study aimed to evaluate the dynamics of microbiological quality based on E. coli concentrations and their relationship with trophic state indicators (TSI) in the dry and rainy season of the waters of the Acaraú Mirim reservoir, located in the Municipality of Massapê - CE, Brazil, between the period 2014 2020. The variables of interest defined were: E. coli counts, Phosphorus and Chlorophyll a concentration, to determine TSI and quantification of cyanobacteria. The results showed that there is a moderate relationship between the levels of precipitation and the concentrations of E. coli in the reservoir, different from the dry period. The relationship between E. coli concentrations and TSI values, and cyanobacterial concentrations, was not correlated. In the comparison between the water quality, considering the analyzed variables and the national standards for classification of class II fresh water, the reservoir presented the possibility of meeting classes I/II.