Assessment of Plant Species Composition and Diversity in Home garden Agroforestry Practices Across Agro-Ecological Zones of Dara district, Southern Ethiopia

Home garden agroforestry systems support biodiversity conservation and rural livelihoods, yet their ecological patterns may vary across agro-ecological zones. This study assessed the effects of agro-ecological variation on plant diversity, species composition, beta diversity, and vegetation structure in Dara District, Southern Ethiopia. 63 home gardens were systematically sampled using 10 m × 10 m plots for woody species and 1 m × 1 m subplots for herbaceous vegetation. Species diversity was assessed using Shannon–Wiener, Simpson, and evenness indices, while beta diversity was evaluated using the Sørensen similarity index. Structural attributes(diameter at breast height, height, basal area, stem density, and Importance Value Index (IVI), were calculated. Differences among agro-ecological zones were tested using ANOVA and Kruskal–Wallis tests at p < 0.05. A total of 214 plant species representing 80 families were recorded, with Asteraceae comprising the largest proportion (7.94%). Herbaceous species accounted for 45% of the flora, followed by trees (27%) and shrubs (21%). Exotic species (56.5%) were more abundant than indigenous species (43.5%). Midland home gardens had the highest species richness (25.86 ± 7.80), Shannon diversity (2.52 ± 0.31), and evenness (0.79 ± 0.07). Beta diversity indicated substantial species turnover, with the greatest dissimilarity between lowland and highland zones (0.65). Structural attributes generally increased with elevation, whereas stem density did not differ significantly. Ensete ventricosum had the highest IVI, while regeneration was limited, particularly in highlands. Agro-ecology-specific management is therefore needed to conserve indigenous species and improve regeneration.