Soil quality in the Sebkhas environment (South-Eastern Constantine), Algeria.

Abstract

The sebkhas (Sabkhet Djendli and Garaat Ank Djemel) considered in our study are part of the Boulehilet plain (ex. Lutaud) located on the southern edge of Constantine's high plains. The soils surrounding these sebkhas are dotted with very sparse vegetation consisting mainly of halophytic plants. These two lakes are drained, respectively, by Oued el Madher and Oued Chemora. Chemical analyses of the soils (about 150 samples) show relatively high concentrations of sodium and sulphates. The latter are more present in the vicinity of Sebkhet Djendli, the source of which would be the leaching of the Triassic formations that lie just to the north-east of the Sabkha. However, the CaCO3 content does not show a significant variation across the plain. As for sodium levels, they increase significantly with depth, especially on the eastern edge of Sebkhet Djendli. The soils of the Boulehilet plain are relatively salty and have a pastoral interest. Conductivity measurements carried out in 70 farmers' wells on the outskirts of Sebkhet Djendli indicate values that are sometimes quite high, exceeding 2000μs, thus corroborating the salinity of the water that is used for domestic supply. Trace elements analyses (Zn, Cu, Cr, Ni, Ba, etc.) of soil samples taken from auger-digged boreholes (12 samples) show relatively high levels. The presence of these metals is thought to be linked to mining waste from previous operations near these sebkhas.