CHARACTERIZATION OF PH, TOTAL DISSOLVED SOLIDS, ELECTRICAL CONDUCTIVITY AND DISSOLVED OXYGEN IN THE LOWER TARUMÃ-AÇU RIVER (AMAZONAS, BRAZIL)

Abstract

This study aimed to characterize the water quality of the lower course of the Tarumã-Açu River, based on the variables: hydrogen potential (pH), total dissolved solids (TDS), electrical conductivity (EC) and dissolved oxygen (DO). To achieve this objective, the qualitative and quantitative methodological approach was used. The samples were collected and analyzed in loco, on March 11, 2020, the hydrological period of flooding on the Negro River. The water collected in the subsurface (-15 cm) in the 18 sampling stations of the Tarumã-Açu River showed less acid characteristics, with an average pH of 5.35±0.25, low concentration in the TDS, with an average of 4.06±0 .87 mg/L, low EC, with a mean of 8.11±1.49 μS/cm and higher concentration of DO, with a mean of 6.03±0.47 mg/L. However, the deep waters (-4 meters) showed more acidic characteristics, with an average pH of 4.87±0.34, low concentration in the TDS, with an average of 5.61±2.45 mg/L, low EC , with a mean of 10.72±3.71 μS/cm and lower DO concentration, with a mean of 3.17±1.98 mg/L. Concerning the characterization of the banks of the Tarumã-Açu river, it was observed that the Igarapés¹ of Mariano, Bolivia and Gigante, located on the left bank of the main channel, contribute to the release of pollutant load in the Tarumã-Açu river basin. Given the above, the results indicate that there are favorable conditions for the dilution of dissolved solids in the lower sector of the watershed. negative consequences from anthropic action.