Identificação e caracterização de corpos de águas salinas no semiárido paraibano.

Abstract

This work is aimed, through research, to get information and evaluate the technical quality of some watre bodies for human consumption, livestock and irrigation, in sources of supplying, located in the watershed of Paraiba River, and the characterization of upstream and downstream land of the 4 sources characterized with high levels of salt. Water samples were collected in three different periods, it means, in dry periods (November/2006), rainy (May/2007) and after the rain (July/2008), while the soil samples, were collected in the basin bed of water abstraction , at depths of 0- 30, 30-60 and 60-90 cm during the second stage of the water collection. Generally, the electrical conductivity of water and other characteristics were higher in the dry season. The chemical composition of all the water was similar and predominantly sulphate or sodium chloride, in both periods. According to the resolution of the Health Ministry and the results of pH, cations and anions, 91,7 % of water samples are unfit for human consumption during the period, as classification for animal consumption and irrigation, only in some exceptions the water can be used. The risk of salinity and sodicity to use this water ranged from high to very high. On the ground, you can classify it based on the samples in saline sodic soils in all municipalities.