Evaluation of the evaporation of ground water and depth of drainage in irrigated lands in saharian area

In the Saharian regions the ground water level in most worked surfaces is about 0 m to 1.5 m and the waters are excessively salty. The evaporation of the surface of the ground water is one of the principal causes of the salization of soils, the over consumption of the resources in irrigation water and the degradation of the environment. The obtained results concerning the evaporation of water of the ground water in the region of Ouargla show that at a depth of 1 m, the intensity of the evaporation equal the evapotranspiration (Enp/Etp = 1) at a depth of 2 m to 2.03 m. Therefore the amelioration of the soils the agriculture yield and the use of the resource in the irrigation water are closely linked to the groundwater evaporation. l