Résumé:
Water is by far the most abundant element of our planet and the essential material for living beings, without forgetting its importance and its essential relationship for the health of the soil and therefore of the environment. The study of rainfall processes in arid and semi-arid regions is well established, with water being the main limiting factor.
To treat our theme, we divided the work into four chapters, the first of which is devoted to a bibliographic search on the studied region (geographical situation, climate, vegetation and hydrology). In the remaining three chapters, we studied the spatio-temporal variability of precipitation using statistical processing and drought index analysis. We therefore adopted a methodology characterized by the collection of precipitation data and the creation of a computer database. For this, we have relied on monthly data from several rainfall stations located in our study area (uplands - central and uplands - western Algeria).
The calculation of the indices for the different stations reveals the existence of two distinct wet and dry periods. The years of drought are all the more remarkable as they can be established for four years. Rainfall has decreased during this period of study, but is also interrupted by other years of heavy rainfall in some areas such as Djelfa and Ksar Chellala. It is as if the further south, the more the impact of the drought is present.
