The anafyàis of thé deuteriúrri excess values found in samples from 43 springs and wells to the southeast of Sierra Nevada shows: (a) a relatively scarce seasonal variability, when compared to the precipitation data, and (b) a positive correlation with the average altitude of the recharge áreas. From (a) can be deduced an important integrating and mixing effect in the carbonate alpujârride aquifers, as well as a flow system neater to the diffuse type than to the karstic «sensu stricto» one. The (b) effect illustrates on the importance of evaporation processes previous to the infiltration, mainly affecting the precipitations of rheditérraheàn origin