Impact de la salinité de Chott El Beida sur la qualité des eaux souterraines de la plaine de Beida Bordj, Sétif, Nord-Est-Algérien.

Abstract

Groundwater salinity poses a problem in arid and semi-arid zones, and damages its quality. The Mio-plioquaternary aquifer system of Setifian high lands is lodged in a clayey and conglomeratic formations, and lacustre inelime stone. It is placed between the Tellian series at North and the Hodneanones at South. It is essentially recharged by precipitation and by a faults governing and favoring groundwater flow. The endoreismis the main character of the region. With regard to the observation period taken into account, the real evapotranspiration mean value is 75 % of the precipitation and that of the infiltration coefficient does not exceed 10 %., the superficial aquifer waters present a moderately to quite high salinity. The latter has even revealed a poorquality. During their paths in depth, water chemical elements have developed two dominant facies: sodium chloride and calcium sulfate. The chemical analysis has there foreshown the dominance of a saliferous ions (Na+, Cl-) and a gypsumones (Ca2+, SO4 2-) comparingwith the carbonates (Ca2+, HCO3 - ).