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Science et changements planétaires / Sécheresse. Volume 10, Number 1, 63-7, Mars 1999, Note de recherche

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Author(s) : Aude Nuscia Taïbi, Akila Kemmouche, Jean-François Parrot

Summary : 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.

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