Is the evaporation from phreatic aquifers in arid zones independent of the soil characteristics?

The approximately 20 published data based on isotopic profiles of the the unsaturated zone lead us to express the evaporative flux as an inverse power function of the piezometric depth below the soil surface, independently of the soil characteristics. Recent publications report suction values tak?en at over 1000 m from the soil surface in arid regions as well as hydraulic conductivities corresponding to these values. These new data allowed us to compute new bounds of the evaporative flux from aquifers in arid regions; they corroborate the weak influence of soil characteristics. (C) Academie des sciences/Elsevier, Paris.