Origin and Impact of Trace Elements on Brines of Chotts and Sebkhas (Saline Lakes) in Algerian Low Sahara

Abstract

The brines in the chotts and sebkhas of the Algerian Low Sahara are solutions characterized by a salinity that far exceeds that of the waters of the sea (120 to 440 g/l). Over the past three decades, these lacustrine systems (chotts and sebkhas) have become an estuary for all types of urban discharge; this situation highlights the environmental impact of these discharges on these lacustrine systems. The chemical analysis of the brines showed that the average concentration of certain trace elements is very high. It is of the order of 2.2 mg/l for Zn, 1.6 mg/l for Cu and 0.03 mg/l for Pb and Ni. These trace elements are trapped in evaporites and clays and are micropollutants that cause nuisance even when they are released in very small quantities.