Water quality and trophic state index in amazônic river: the case of Pará do Uruará river

Abstract

The large waterway network in the Amazon has significant importance for the riverside population, being of fundamental importance for the survival of humans and nature. Based on that, this research aimed to evaluate the water quality of an Amazon river, through physical, chemical and/or biological parameters, as well as to estimate whether there is seasonality influence and to evaluate the trophic state index (TEI) . The study area comprises the waters of the Pará do Uruará River, which bathes the District of Santa Maria do Uruará, municipality of Prainha-PA. Four points along the river were analyzed, within a perimeter of 4 km, which were named: points 1, point 2, point 3 and point 4, in two seasonal periods (winter/summer), and the variables of electrical conductivity were evaluated, chlorophyll A, apparent color, hardness, total phosphorus, turbidity, dissolved oxygen, pH, temperature, thermotolerant coliforms and Eschirichia coli. According to the results, it was possible to observe that the physical-chemical and microbiological parameters showed in 3 of the 4 points that the color did not comply with the GM/MS Ordinance No. 888 of 21. In addition, the variable of dissolved oxygen in 3 points did not comply with CONAMA resolution n° 357/05 in the winter period. Regarding seasonality, the research showed that there are significant differences in water quality, according to the period in which it is being evaluated. From this work, it is possible to see that studying the quality of water in riverside communities is of paramount importance and that it is necessary to implement new public policies aimed at protecting water bodies, as well as alerting the population about the importance of preserving the water. water quality and the environment.