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Détermination des dynamiques d’évolution morphologique et végétale combinées des « dayas » du piémont sud de l’Atlas saharien (Algérie) par télédétection Volume 10, issue 1, Mars 1999

Authors
Laboratoire CNRS de géographie physique Pierre-Birot UMR 8591, 1, place Aristide-Briand, 92195 Meudon cedex, France, Laboratoire de traitement d’images institut d’électronique, Université de sciences et technologie Houari-Boumédiène, BP 32, Bab-Ezzouar, 16111 Alger, Algérie, Laboratoire de géologie-géomorphologie structurale et télédétection, Université Pierre-et-Marie-Curie, case 129, 4, place Jussieu, 75252 Paris cedex 05, France, Laboratoire de géologie-géomorphologie structurale et télédétection, Université Pierre-et-Marie-Curie, case 129, 4, place Jussieu, 75252 Paris cedex 05, France. ORSTOM, 213, rue La Fayette, 75010 Paris, France.
  • Page(s) : 63-7
  • Published in: 1999

The Ras ech Ch’aab hamada, on the southern piedmont plain in the Algerian Saharan Atlas region, is characterized by dayas, i.e. small semi-circular depressions colonized by dense vegetation. These dayas, which are found in chain-like groups, show specific morphological variations : small nascent dayas increase in size with age and become increasingly irregular and embanked. The vegetation cover also becomes scattered and disappears altogether in the middle of the oldest dayas. A correlation was noted between their morphology and stage of development. Vegetation and shape criteria concerning these daya structures, as determined from remote-sensing data, were used to enhance the accuracy of the correlations and to map all dayas in the Ras ech Ch’aab hamada.