Qualidade da água de fontes hídricas da Sub-bacia do Baixo Jaguaribe, Ceará, Brasil

Abstract

The water is an essential natural resource for the maintenance of life, as well for the execution of various economic activities realized in society. In recent years, a greater attention and quality of water resources has been observed, since water is a finite resource, susceptible to adversities and contamination by polluting activities, which makes it essential to carry out a monitoring of water sources. This work had as objective to evaluate the quality of water for irrigation, human and animal consumption, in surface and subterranean waters located in sub–basin of Baixo Jaguaribe, state of Ceará, Brazil. For this purpose, it was realized a monitoring to evaluate the spatial and temporal variability in 75 points, encompassing surface waters, shallows wells and deep wells, in four collects. The collects were done over the years 2016 to 2018. In field were evaluated the static level of wells, with the objective of to verify if there was depletion or recharge of water in studied period. In laboratory, it was determined the concentration of salts and contamination by heavy metals. The data were evaluated for descriptive statistics (average, minimum, maximum and coefficient of variation) and by the technique multivariate of the analysis of main components, to identify the main components responsible for the variation of quality among the points, correlations between the variables of salinity and heavy metals and the similarity among points. The interpretation of results was assisted by limits for Environmental Sanitation Technology Company (Cetesb) of 2014. Concludes. It was concluded that the water quality of the left bank of the Jaguaribe River presented greater restriction for use in irrigation than the right bank of the river, with more severe restriction during the dry period. Among the types of water sources, greater restriction was obtained for irrigation in the waters of deep wells than in the shallow wells and surface water. The waters presented contaminations by metals Al, Fe, Mn and Pb. Rainfall during the evaluation period was not sufficient to recharge the aquifers of the Baixo Jaguaribe Sub–Basin.