Science et changements planétaires / Sécheresse
MENUDétermination 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
- 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.