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A. Annexe, Illustrations de la croûte biologique et des micro-organismes la constituant Croûte biologique sur sol nu au Sahel (Languille, 2009.

. Microorganismes, cyanobactérie -Microcoleus vaginatus (a), lichens -Psora decipiens et Collema coccophorum (b) et mousses -Syntrichia caninervis

C. Annexe, Les axes de recherché du projet BioCrust (d'après O. Malam Issa, 2009) CemOA : archive ouverte d'Irstea / Cemagref

H. Annexe, Quelques exemples de cartes d'humidités Banizoumbou, 29 mai, méthode 1, mailles de 100x100 pixels Banizoumbou, 29 mai, méthode 1, mailles de 500x500 pixels CemOA : archive ouverte d'Irstea / Cemagref