Ecological condition of encroached and non-encroached rangelands in Borana, Ethiopia

The range condition was assessed in six communal grazing areas and one Government ranch in both areas encroached by bushes or shrubs and non-encroached areas. In each area, three altitude zones were distinguished and in each altitude zone one transect, covering both encroached and non-encroached rangeland, away from water sources, was selected. The assessment was based on botanical composition of the herbaceous layer, basal cover, litter cover, relative number of seedlings, age distribution of grasses and soil condition. A total of 41 grasses, four legumes, three sedges and 28 tree and/or shrub species were identified. The grasses Aristida adscensionis. Cenchrus ciliaris, Chrysopogon aucheri and Panicum coloratum were common or dominant in all sampled areas, Pennisetum mezianum and Pennisetum stramineum were typically found in the encroached vegetation. In general, the range condition was good. The encroached vegetation had a significantly lower score for range condition than the non-encroached vegetation for most of the parameters as well as for the total score, although the differences were small. Differences based on altitude and distance of sample sites from water sources within transects were not significant, except for the relative number of seedlings. No signs of overgrazing were detected.