Contribution of Hagenia abyssinica and Schefflera abyssinica Selected Parkland Trees on Soil Properties and Wheat Productivity in Ana Sora District of Guji Zone, Southern Ethiopia

The study was conducted to evaluate the contribution of Hagenia abyssinica and Schefflera abyssinica selected parkland trees on soil properties and wheat productivity in Ana Sora District of Guji Zone, Southern Ethiopia. Key informant interview was used to identify farmers selection criteria and purpose of keeping parkland tree species of the study area. The study results showed that, Schefflera abyssinica, Hagenia abyssinica, Millettia ferruginea, Cordia africana and Croton macrostachyus were the most preferred top five parkland tree species of the study area respectively. Regarding selection of parkland tree specie for soil and crop related studies the most preferred 1st and 2nd ranked parkland trees namely; Schefflera abyssinica and Hagenia abyssinica were selected. Three isolated trees of each species which had similar management practice and grown under similar soil types, climate and landscape were selected on each of the study site and the canopy coverage of each tree was divided into three radial distances (2.3m,4.6m and 15m). The results of the study indicated that except for soil particle fractions the amount of major soil fertility parameters such as soil pH, CEC, OC, OM, TN and available P, under canopies of Hagenia abyssinica and Schefflera abyssinica parkland trees were higher than the open cultivated land. Moreover, the effects of the two parkland trees on grain yield of wheat was higher within the canopy of the tree than outside of the canopy. Therefore, the findings suggest that the maintenance of soil fertility and improvement in grain yield of wheat can be attained by incorporation of the two parkland trees in the study area and agricultural landscapes of similar agro-ecological conditions.