Conclusion et perspectives
Cette étude a porté sur les croûtes
microbiotiques de la région de Banizoumbou au Niger. Les
résultats obtenus montrent que l'hydrophobicité des croEtes
microbiotiques est une caractéristique variable selon le taux de
couverture, la biomasse microbienne et l'usage des sols.
Les croûtes microbiotiques issues des parcelles
protégées contre le passage du bétail et des humains
montrent un degré d'hydrophobicité plus élevé que
les parcelles soumises au p1turage. Cette caractéristique semble Itre
accompagnée par des taux de couverture et de biomasse microbienne
élevés.
Ce travail constitue une étude préliminaire qui
servira de base à la compréhension du comportement de la
dynamique de l'eau à la surface des sols portant des croItes
microbiotiques dans la zone sahélienne du Niger. L'étude d'autres
types de croItes microbiotiques permettra d'élargir la gamme de
données sur l'hydrophobicité.
La connaissance de paramètres comme la teneur en
fraction fine, la matière organique totale et la teneur en produits de
sécrétions polysaccharidiques (EPS) dans les horizons
encroûtés permettront une meilleure compréhension de la
variabilité de l'hydrophobicité.
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