Soil Properties under Selected Homestead Grown Indigenous Tree and Shrub Species in the Highland Areas of Central Ethiopia

Abstract

A study was conducted in Galessa-Jeldu areas to evaluate soil pH, organic C, total N, available P and exchangeable bases under four indigenous and one exotic tree species, and to examine the correlation between the different soil properties. The tree and shrub species included in the study were Senecio gigas Vatke, Hagenia abyssinica (Bruce) J.F. Gmel., Dombeya torrida (J.F. Gmel.) P. Bamps, Buddleja polystachya Fres. and Chamaecytisus palmensis (Christ) Bisby and K. The first four are indigenous, while the last one is an exotic N-fixing species. The soil pH values under H. abyssinica and S. gigas were above 6.34 as compared to the soil pH values under C. palmensis, D. torrida and B. polystachya. Total N was slightly higher under H. abyssinica although not statistically

different with the N content under other species. Organic C was higher under H. abyssinica than under B. polystachya. The variation for exchangeable K was more at 0-15 cm soil depth than at the 15-30 and 30-50 cm soil depths. The correlation between soil pH and total N as well as pH and organic C was positive in almost all the

horizontal positions. Hagenia abyssinica, S. gigas and C. palmensis are some of the potential species that can be evaluated in different land-use systems of the high altitude areas to protect the loss of plant nutrients.

Keywords: High Altitude; Total N; Organic C; Exchangeable Bases; Soil Fertility; Nutrient Cycling