[01] Sabri Kanzari, National Institute of Research of Rural Engineering, Waters and Forests of Tunis, INRGREF, Laboratory of Rural Engineering, University of Carthage, Ariana, Tunisia. [02] Sana Ben Mariem, National Institute of Research of Rural Engineering, Waters and Forests of Tunis, INRGREF, Laboratory of Rural Engineering, University of Carthage, Ariana, Tunisia. [03] Béchir Ben Nouna, National Institute of Research of Rural Engineering, Waters and Forests of Tunis, INRGREF, Laboratory of Rural Engineering, University of Carthage, Ariana, Tunisia. [04] Mourad Rezig, National Institute of Research of Rural Engineering, Waters and Forests of Tunis, INRGREF, Laboratory of Rural Engineering, University of Carthage, Ariana, Tunisia.

In arid and semi-arid regions are characterized by the high evaporation rates which increases the solute accumulation in the unsaturated soils. Hydraulic properties are essential for modeling water flow and contaminant transport. In this paper, the effect of high solute concentration is studied in three different soils (Clay, Loam and Sand) through the measurement of the retention curves by a simple evaporation method using two water qualities (distilled water and water with a total solute concentration of 5 g.l^-1). The measured values were fitted on the van Genuchten model by the RETC software in order to obtain an estimation of the hydraulic parameters. The results show that there is a significant effect for the water retention curve of the clay soil which increases. On the contrary, for the sand and the loam soils the effect is not significant.

Unsaturated Soils, Hydraulic Properties, Parameter Optimization, RETC, Soil Retention Curve

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