Abstract:
Shade based coffee agroforestry systems have a considerable contribution to support biodiversity. Yet assets and limits of their contribution are insufficiently documented. Understanding the diversity and management of shade trees are important to maintain the balance of productivity and biodiversity conservation in human made landscapes such as coffee agro-ecosystems. The objective of this study was to assess tree species diversity, preference and management in small holder coffee farms in Bedeno district, East Hararghe Zone, Ethiopia. Eleven kebeles were selected purposively and four of them were randomly selected from which 119 households were selected for this study. Tree inventories were made in a selected 119 smallholder coffee farms. The household survey has involved questionnaire based respondent and key informant interview. The study was carried out in between October 28, 2019 and April 15, 2020. Data was analyzed by Statistical Package for Social Sciences (SPSS) version 20 and Microsoft Office Excel 2010, using descriptive statistics such as means, percentages and frequency. A total of 53 tree species representing 28 families, constituting 69.8% indigenous and 30.2% exotic species were recorded in coffee farms. There was significant difference (p<0.05) between three wealth categories across four study kebeles and wealth status of the household influenced the tree species diversity of coffee farms. The rich class was found to own more diversified tree species. The highest and lowest mean value of richness (11.5, 3), Shannon index (2.3, 0.9) and abundance (22.8, 4.8) were recorded on the farm of rich and poor household respectively. There was no significant difference among the study kebeles and the position of kebeles was not influenced tree species diversity in this specific study. Farmers selected four multipurpose and indigeneous tree species in the order of Cordia africana>Acacia albida>Croton macrostachyus>Millettia ferruginea for coffee shade, using leaf lifespan, height, growth rate, leaf size, crown shape, leaf decomposition rate and root depth tree attributes as criteria. The sources of planting materials were from own sources, neighboring farmer, government nursery and self-raised. Hoeing, weeding, watering, manuring and fencing, pruning, thinning, pollarding and coppicing were the most common management practicest for the coffee farm. It was concluded that, coffee based agroforestry system is important land use system in conserving tree species diversity and should be encouraged.
