Le bassin-versant de l'Oued Zaz (région de Ouezzane). Etude géographique mise au service de l'hydrologie (Maroc)
Institution:
Toulouse 2Disciplines:
Directors:
Abstract EN:
This research has aspectific aim : to make its contribution to the hydrologic study of a drainage basin which hasn't got any hydrometric equipment, the river zaz's one(area of ouezzane, morocco). We have succeeded in collecting a vast amount of hydrologic and geomorphologic data by means of geographic, scientific method. Through the observation of the ground which is minutely detailed. And the global understanding of the drainage basin, its complexity and its dynamic characteristic which can be seen through its various geographic components (geological structure, slope system, biogeographic structure, climatic structure and society). Processing these data has enabled us to define the hydrologic system of the drainage basin in space and in time, through sharp analysis, delimitation and cartography, that is : - first the real functional drainage pattern at the time of the total saturation of the drainage basin, its draining off density and its dynamics. - secondly the hydrologic seasons,their date of occurence, their intensity and length frequency, their hydrologic stages and their geomorphologic procedures. - finally the hydrologic soils : homogeneous sections of space which experience the same hydrologic reactions and procedures under an identical climatic sequence. The thorough knowledge of hydrologic soils and hydrogeomorphological dynamics which characterize them have enabled us to respond to the development demands in order to protect the natural environment. To that effect measures of protection and safeguard for each soil have been suggested. Thus allowing us to convert the present agricultural system, which is a social and ecological crisis, into an agricultural system which would permit "fellahs"* to improve their standard of living and allow them to fight in a methodically intelligent way against the destruction of the soils and their hydrologic reserves.
Abstract FR:
Notre recherche se veut une contribution a l'etude hydrologique d'un bassin-versant sans equipement hydrometrique : celui de l'oued zaz (region de ouezzane - maroc). Par l'emploi d'une methode geographique scientifique. Par l'observation minutieuse de terrain, la comprehension du bassin-versant dans sa totalite, sa complexite et sa dynamique a travers toutes ses composantes geographiques (structure geologique, systeme de pentes, structure biogeographique, societe et structure climatique), nous avons reussi a collecter de riches informations hydrologiques et geomorphologiques. Le traitement de celles-ci nous a permis de cerner le regime hydrologique du b-v. Dans l'espace et dans le temps et ce, en analysant, en delimitant et en cartographiant finement : - le reseau hydrographique reel fonctionnel lors de la saturation totale du bassin-versant, sa densite de drainage et sa dynamique. - les saisons hydrologiques,leur date d'occurrence, leur frequence-intensite-duree, leurs phases hydrologiques et leurs processus geomorphologiques. - enfin,les terroirs hydrologiques : portions d'espace homogenes connaissant les memes reactions et processus hydrologiques sous une meme sequence climatique. La connaissance approfondie des terroirs hydrologiques et de la dynamique hydrogeomorphologique qui les caracterisent nous a permis de repondre aux exigences de l'amenagement et de la protection du milieu naturel. Dans ce but, des mesures de protection et de sauvegarde pour chaque terroir ont ete proposees. Leur realisation permettrait de convertir le systeme cultural actuel qui est en train d'engendrer une crise ecologique et sociale en un systeme cultural qui permettrait aux fellahs d'ameliorer leur niveau de vie et de lutter de facon for intelligente contre la destruction des terroirs et de leurs reservoirs hydrologiques.