The natural vegetation of Babile Elephant Sanctuary, Eastern Ethiopia: Implications for biodiversity conservation

Abstract

A floristic analysis of the natural vegetation was carried out in the Babile Elephant Sanctuary (BES), in semi-arid part of eastern Ethiopia. A total of 75 quadrats, each 400 m², were analyzed following a stratified sampling design. A total of 237 plant species, belonging to 155 genera and 57 families, were identified. Fabaceae was represented by the highest number of species (i.e., 36 species; 15.1%). Six community types were identified using the TWINSPAN program. These are: I. Tamarindus indica; II. Acacia robusta; III. Acacia seyal - Balanites aegyptiaca; IV. Acacia senegal - Acalypha fruticosa; V. Terminalia brownii - Boswellia neglecta and VI. Acacia bussie - Grewia tenax types. A total basal area of 17.8 m2/ha, and a density of 385 ± 114.2 (S.E.) individuals ha-1 were calculated for 67 woody species (22 trees, 36 shrubs and 9 climbers); the mean density of trees was 32 ± 9.96, shrubs 619 ± 203.3 and climbers 315 ± 103.4 individuals ha^-1. A very high impact was imposed by the invasive species Lantana camara, which had a density of 2794.6 individuals ha^-1. In general, the vegetation of the sanctuary was threatened by human encroachment, intensification of commercialized farming and invasive species. Therefore, as the habitat for the only known population of the isolated, ecologically distinct subspecies population of the elephant (Loxodonta africana orleansi), the BES should be afforded the highest conservation priority as a matter of urgency.

Keywords/phrases: Babile Elephant Sanctuary, Community types, Conservation, Floristic analysis, Species diversity

Ethiop. J. Biol. Sci., 10(2): 137-152, 2011