Woody Species Diversity and Composition of Dry Woodland Vegetation in West Shewa, Central Ethiopia: Implications for Their Sustainable Management

The dry land forest of Ethiopia possesses diverse tree species that are known for their ecological and economic values. Despite growing recognition of environmental and economic benefits of these species, the woodland harbouring these species is degrading. Adequate knowledge on the resource base including the current status of its population is crucial for sustainable management of the forest resource. Therefore, this study was carried out to investigate the diversity and composition of woody species in Kara dry lands forest. A total of 90 quadrants were established along transect lines. A 400 m2 quadrants was used, distance between quadrants and transecting lines were 200 m and 500 m respectively. Species diversity and evenness, density, frequency, important value and regeneration status were assessed. This study reveals total of 48 woody species representing 23 families and 31 genera’s were found. Out of that, 13 woody species were identified as gum and resin bearing species. The genus of Commiphora and Acacia species were found to be the dominant gum and resin bearing species at the study area. Diversity of the entire woody species assemblage and of the gum- and resin-bearing species was H= 3.47 and H= 2.3 respectively. The evenness values of entire and gum and resin producing woody species were 0.67 and 0.77 respectively. The gum and resin producing woody species accounted for 44.56% of the density, 49.87% of the basal area and 45.49% of the Importance Value Index. However, we recorded the declining natural regeneration of most gum- and resin-bearing woody species except for a small number of species, which exhibited signs of healthy populations. Generally, the results of the present study highlighted the absence of conservation actions that will probably be subject to a progressive decline of gum and resin bearing species because of uncontrolled grazing, charcoal production and shifting cultivation. Therefore, proper management plan and domestication of the species through artificial regeneration and area closure are urgently needed.