Diversity, density and management of trees in different agro-forestry practices of Yem Special District, Southern Ethiopia

Abstract

Conserving tree species diversity cannot be restricted to forest areas because of increasing encroachment to remaining forests. Agricultural landscapes can also maintain tree species diversity where the native habitats are heavily diminished and/or merit conservation. The present study was conducted in the agroforestry practices of Yem Special District, Southern Ethiopia, to determine the diversity, composition and density of trees, and assess farmers’ tree management practices. The data were collected through two consecutive field surveys involving structured household questionnaires administered in 126 households, and making inventory of the woody species. Data were analyzed using one way anova, and Chi-square, Kruskal-Wallis, and Mann-Whitney tests. The status of tree species richness and diversity were quantified for the different agroforestry practices. A total of 100 tree and shrub species belonging to 57 families and 83 genera were recorded in the different agroforestry practices of individual household farms, of which 11 (or 11%) were exotic and 89 (or 89%) native species. The mean value of tree species per household for the overall agroforestry practices was 14.04 and it was found to be significantly different among sites, mainly due to differences in agroecology and road access. Tree species richness was influenced by distance to major roads, wealth status, farm size and family size. The study revealed that the agroforestry practices contribute to the conservation of agrobiodiversity.