Comparative study of the salinization process in surface water reservoirs located in two distinct regions in Southwestern Bahia, Brazil

Abstract

In this study, the influence of the rainfall variability in the salinization process in surface water reservoirs located in two distinct regions in southwestern Bahia, Brazil was evaluated with basis in the temporal variation of electric conductivity (EC), sodium, potassium, calcium and magnesium contents on the water samples collected in the reservoirs. Two reservoirs built on ocean watercourses were chosen: the Anagé reservoir, situated in the semi-arid zone and the Água Fria reservoir, located in the atlantic forest transition zone. The determination of Na, K, Ca and Mg were carried out by flame atomic absorption spectrometry (FAAS). The result obtained form this study indicates that the circulation and distribution of the chemical species in both water systems are relatively well defined. However, the water form the Anagé reservoir presented the largest variations in the values of the electric conductivity and sodium adsorption ratio (SAR) between of two collection periods, demonstrated a larger influence of the rain regime in the water quality of reservoir located in semi-arid zones. © 2011 Sociedade Brasileira de Química.