Quality of aquifers in the Aïn el Atti region (immediate upstream of the Tafilalet plain)
The present results were obtained with the project IAEA-TC (INT/5/144) on the sustainable utilisation of the saline groundwater and wastelands for plant production at the Aïn el Atti region. This zone lies within the Saharan climate with less than 90 mm as the average annual precipitation. This site is characterized by the existence of for aquifer’s systems: the Infracenomanian, the Turonian, the Senonian and the Quaternary. In this region, a network of 20 water points has been the purpose of the physical-chemistry analysis (pH, T°C, EC.) to follow the groundwater saline evolution, identify its origin and estimate the groundwater recharge. These samples were taken once every three months from the Ziz River, the Quaternary (4), the Senonian (4), the Turonian (4) and the Infracenomanian groundwater (4). Overall, we distinguished between three types facies: (i) Sodium-Chloride for the artesian well, the Quaternary and the Ziz river, (ii) Calcium-Sulfate for the Turonian aquifer with the evolution towards Calcium-Chloride and (iii) Calcium-Bicarbonate for the Senonian aquifer. According to the USSL classification Salinity Laboratory (1954), the dominant class is C5S3-4. However, the high salinity and sodicity of these groundwater does not cause neither reduction of permeability and nor surface soil salt accumulation.