ESTIMATION OF THE PHENOMENON OF RECHARGE AND EVAPORATION OF GROUND- WATERS UNDER SEMI-ARID CONDITIONS -PLAIN OF TAFILALT - SOUTH OF MOROCCO
The area of study, located in the Saharan borders, to the south of the high atlas, extends on more than one thousands of km2; this area knows an arid climate (less than 100 mm per year of precipitation) doubled of an irregular pluviometry. Since the construction of the stopping Hassan ED Dakhil upstream of the area which deprived Tafilalt of water of the Ziz oued, an artificial recharge is assured by intermittent lâchers water of the stopping.
The isotopic and chemical study of the soil profile in the unsaturated soil of approximately 6,5m shows that with the top a depth of approximately 111mm, water is taken again under the effect of evaporation. According to Barnes and Allison, the modeling of the phenomenon has provided an evaporation rate estimate of 7mm/year.