Human Impact and the Deterioration of the Lower Sahara Wetlands

The geochemical deterioration of the Ain El Beida chott was highlighted following observations of this wetland from December 2010 to May 2011. Geologically, the bottom, composed of sand, evaporites, and undegraded organic matter, is characterized by significant lateral variation in facies. The chemical facies of the waters ranges from chloride to sodium and potassium chloride. The pH, salinity, density, and alkalinity of the waters, as well as the concentrations of major ions, show abnormal changes during the observation period; spatially, they highlight the heterogeneity of the chott's waters. This is an ephemeral lake strongly influenced by human activity and highly sensitive to variations in climatic conditions. Indeed, the constant inflow of wastewater and irrigation water, along with alternating hot and cold periods, causes recurrent halts in evaporation, leading to geochemical dysfunction in this ecosystem, which is classified as a desert wetland.