Análise da qualidade da água em ambientes fluviais semiáridos em São João do Tigre/PB

Abstract

Coexistence with drought has been a recurrent theme in recent years, especially when it was found that combating this phenomenon had been lost over time, exposing thousands of people to the risk. Among the great adversities imposed on the semi-arid region, water scarcity is the main one. The high evapotranspiration rates, the great spatial and temporal irregularity of the rainy events, added to the lithological characteristics, contribute to the fact that the water does not meet the needs in the periods of prolonged drought. An efficient management of the scarce water resources in the semi-arid region presupposes the knowledge and characterization of its sources. Knowing that the crystalline geology covers almost the entire northeastern semi-arid region, the water quality was evaluated in two of its main alluvial and fissural aquifers. For this, the main drainage channels of the Tigre’s creek basin, in São João do Tigre, semi-arid region of Paraíba, were selected and samples of water from amazon or shallow wells and deep wells were analyzed along these channels. The water analyzes were performed through a multiparameter probe and also in the laboratory. The main parameters analyzed were Ph, salinity, conductivity, total dissolved solids, chlorides and hardness. Based on the results obtained, it was concluded that all the samples extracted from fissural and alluvial aquifers presented brackish waters, according to the classification of the National Environmental Council, while another 5, out of a total of 9, were classified as unsuitable for the consumption, by the standards of potability established by the Ministry of Health, when the total dissolved solids concentration was evaluated. In the analysis of the other parameters, samples were also identified in disagreement with the established standards.