Influência da precipitação na qualidade da água de mananciais superficiais no município de Poços de Caldas – MG

Abstract

The aim of this study was to investigate the influence of the seasons, water springs and water spring season interaction in relation to the water quality parameters of the water springs of the city of Poços de Caldas, MG, through statistical analysis: F test, ANOVA and their residue analyzes, Kruskal-Wallis test and Dunn's test. The means obtained in the five years of study were also compared with the values of the COPAM/CERH resolution. The 5% significance test F observed that the number of parameters that are influenced by the season increases when the data set from 2013 to 2017 is analized simultaneously, due to the greater number of data processed. The water spring most influenced by the season was Cipó, with 17 parameters with statistically significant differences and the least influenced was Ribeirão da Serra, with 12 parameters with statistically significant differences. In the Kruskal-Wallis test, the total bacterial count, total coliforms, thermotolerant coliforms, temperature, color, pH, residual chlorine, turbidity, fluoride, manganese, iron, chloride, DO, BOD, ammoniacal nitrogen, TDS, nitrate and phosphate were influenced by the water spring-season interaction. The behavior of this interaction was observed through Dunn’s test. The study provided data that prove that the water springs of Poços de Caldas are influenced not only by the season, but also by the water springs that is part of the water body and the water spring-season interaction.