Indicadores de qualidade da água em área rural da microbacia do Rio Apéu, Pará.

Abstract

This study aims to evaluate the use of surface and underground water in agricultural activities, in addition to proposing an index of water quality for use in irrigation (IWQI) in a rural area in the municipality of Castanhal, Northeast of Pará State. The frequency of water sample collection occurred once a month from september/2018 to August/2019, georeferenced, with in situ determination of qualitative parameters, such as: pH, DO, CE, TDS. For the determination of Al, Fe, Ca, Na, Mg, Zn metals, the samples were preserved and sent for analysis in the laboratory at Instituto Evandro Chagas. The individual evaluation of the results obtained were compared with the standard values established in CONAMA resolutions no 357/2005 and no 396/2008, allowing us to say that in the water collected, its parameters are in accordance with what is recommended by the current legislation. Due to the applied sodium adsorption ratio methodology, it was noticed that there were no restrictions on the use of surface and underground water in the irrigation activity throughout the year. In the elaboration of the IQAI, the water classes presented excellent classification for most of the qualitative parameters.