Effect of Coffee Management on Composition and Regeneration of Woody Species in Hurumu District, Ilu Ababor Zone, Oromia Region, Southwestern Ethiopia

Abstract

Traditional coffee management varies across location and may result in different effect on structure and regeneration of woody species. This study was aimed to investigate the effect of forest coffee management practices on composition and regeneration of woody species in Hurumu District Ilu Aba Bor Zone, South West Ethiopia. The forest was divided into undisturbed natural forest and managed coffee forest. 10(ten) transect lines and a total of 8 plots (4 for coffee forest and 4 for natural forest) of 20x20m area were established in each transect at a distance of 200m and the distance between the lines was 100m to collect the vegetation data. Within the main plot 5x5m sub-plots are nested for saplings and seedlings woody species respectively. All plant species found in each plot were identified and counted and their DBH was measured following standard procedures. Diameter at breast height (DBH), Height and inventory data on all woody species were collected from 20 m × 20 m plots. Seedling and saplings were collected from the 5 m × 5 m plots. In the field species were identified by their local names (Afan Oromo). For scientific name identification, the sample specimens were brought to Jimma University Herbarium. In the Herbarium, Identification was carried out using Flora of Ethiopia and Eritrea (Edwards et al., 2000; Hedberg et al., 2006) and Useful trees and shrubs for Ethiopia (Bekele 2007). The voucher specimens were deposited at Jimma University Herbarium. Shannon diversity index and Sorensen’s similarity index were used to analyze vegetation data. The indexes were calculated using the formula following Magurran, (2004), and thereby constructed into bar graphs and tables that show species composition and regeneration status of the two forests. Regeneration status of woody species in coffee forests and natural forest was analyzed by comparing the number of saplings and seedlings with the matured trees following method used by