Rangeland condition and trend in the semi-arid Borana lowlands, southern Oromia, Ethiopia

Abstract

Rangeland condition assessment was conducted in the Borana lowlands, southern Ethiopia to determine the current status and future trend of the grazing land with emphasis on comparing different functional land use units, called Kalo, Worra and Foora. An approach that integrated data from herbaceous and woody plants, soil and pastoralists' perceptions was followed. Density and canopy cover of woody plants were determined in 123 plots of 500m2. Scores of grass species composition, basal cover, litter cover, number of grass seedlings, grass age distribution, soil erosion and compaction were recorded from 615 subplots of 0.25m2. Furthermore, relationships between rangeland condition score and herbaceous biomass production, percent bare soil, and density, frequency and percent cover of woody plants were determined by applying multivariate analyses. The overall rangeland condition appeared to be in a transitional state from good to poor with a downward trend. Principal Components Analysis (PCA) and Redundancy Analysis (RDA) illustrated that woody plants were negatively correlated with rangeland condition score, botanical composition and basal cover of grasses. The pastoralists perceived that woody plants encroachment, lack and/or shortage of rain, and ban of rangeland burning were among the major factors that caused rangeland deterioration. Therefore, rangeland rehabilitation, re-utilization of fire as a rangeland management tool, and selective clearing of woody plants are recommended as a result of this study.