Caractérisation des pâturages herbacés sahéliens à accès limité : Cas du Centre Secondaire de Multiplication de Bétail de Sayam (Diffa).

Objectives : This study aims to characterize the current state of the herbaceous pastures of the Sayam Secondary Cattle Multiplication Center. Methodology and Results : Four pastoral groups have been identified and described from 56 linear surveys carried out on a South North transect. A total of 98 herbaceous species distributed among 59 genera and 27 botanical families have been listed. The best represented genera are: Eragrostis, Ipomoea, Aristida, Cenchrus, Indigofera, Digitaria and Brachiaria. They represent about 50% of the total and contain most of the species of good pastoral value. The overall recovery, the gross and net pastoral values are respectively 85.5%, 75.05% and 67.56%, these attest that the pasture of the center is of good quality. The overall productivity of herbaceous phytomass was estimated at 2.26 tMS / ha with an overall carrying capacity of 0.40 TLU / ha / year, ie 2.5 ha / TLU / year. Analysis of the forage spectrum indicates that species of good pastoral value and those of low pastoral value dominate the grass cover. The first category dominates the better protected central zone while the last occupies the peripheral parts subject to heavy livestock exploitation. Conclusion and applicability of results : The colonization front of poorly palatable species is progressing towards the center under the effect of strong pastoral pressure. Hence the urgency to enclose the entire perimeter of the center in order to avoid creating an ecological imbalance detrimental to the survival of many species dependent on these particular miles. With a view to the rehabilitation and sustainable management of these pastoral centers, this study provides additional information on the current state of the herbaceous pastures in this center.