Perennial plant species composition and diversity in relation to socioecological variables and agroforestry practices in central Ethiopia

Tropical deforestation and forest degradation have resulted in substantial losses of goods and services and a decline in the quality of life. Agroforestry is a viable land-use option to counteract such declines in ecosystem services, including biodiversity and supporting local livelihoods. However, it is unclear how socioecological factors mediate these roles, which hinders the implementation of initiatives to conserve biodiversity. This study aimed to investigate perennial plant species composition and diversity in relation to socioecological variables and agroforestry practices in central Ethiopia. The vegetation data were collected from 243 sample farms that belonged to 81 randomly chosen households from nine kebeles. Across all practices, 92 plant species from 75 genera and 46 families were identified. Of these, 77% were native plant species, and the remaining were exotic ones. Margalef species richness and the Shannon diversity index were both significantly higher (p < 0.05) in homegardens and middle elevations. Furthermore, species richness and the Shannon diversity index were positively and significantly related to slope, farm size, farm age, and wealth status. Parklands, lowland altitude, and younger farms had the highest Simpson's evenness, whereas wealth status, farm size, and slope had no significant association with Simpson's evenness. Overall, this study showed that agroforestry serves as a refuge for native species and helps reverse species loss in natural forests. However, native species are gradually being replaced with exotic species, compromising the integrity of agricultural landscapes. Our study also emphasizes the urgent need to consider socioecological factors when examining biodiversity and planning agricultural landscape management strategies.