Qualidade da água do Rio Macaco, Município de São Lourenço do Oeste, Santa Catarina

Abstract

Water is an essential resource for humanity. The universal solvent characteristic makes it more prone to physical, chemical and biological changes, compromising its quality. The present study had the objective of monitoring the water quality of the Macaco River, located in the city of São Lourenço do Oeste - SC. The extension analyzed covers about 5 km in a rural area. The monitoring of water quality was carried out during the period of one year, from December 2017 to the end of November 2018, respecting the seasons of the year. Being two collection points, the first point upstream of the Macaco River and the second point located before the capture for public supply. The parameters analyzed were biochemical oxygen demand, chemical oxygen demand, thermotolerant coliforms, nitrogen and phosphorus. The data obtained received statistical treatment with the aid of RStudio software, through the Tukey test. The parameters were analyzed individually and compared to the limits established by Resolution No. 357/2005 of the National Environmental Council (CONAMA), except for the biochemical oxygen demand that was used to obtain the degree of biodegradability of Rio. Organic matter and significant impact on phosphorus. The quantification of thermotolerant coliforms was low, but with great pathogen potential, indicating fecal contamination. Seasonality interfered mainly with nutrient dilution, decreasing concentrations in seasons with higher rainfall. The water quality of the Macaco River was affected by its surroundings, with a higher indication of pollution from domestic dumps and fecal contamination.