Modelo de qualidade de águas superficiais para simulação de salinidade em reservatórios de clima semiárido

Abstract

This paper aims to analyze the impact of climate variability on the concentration of salts in semi - arid climate reservoirs by developing a zero-dimensional model of surface water quality for reservoirs. The model is based on the simultaneous resolution of water and salinity mass balances equations. To solve the balance equations, maximum capacity, historical series of affluent flows, quota-area-volume and evaporation data, that were obtained from the State Water Resources Management Company (COGERH), were used. A constant and theoretical affluent concentration of 100 mg /L was considered. The elaborated model simulated the temporal evolution of the salt concentration for the reservoirs of the Upper Jaguaribe Basin in the State of Ceará for a period of 100 years (1912-2012). The results showed that the salinity varies inversely with the volume, increasing drastically during drought periods. It was concluded that the process of allocation and operation of hydro systems should take into account parameters of water quality, considering the impact of the variation of the amount of water stored on it and the aggravation of both during periods of drought.