Contributions of coffee-based agroforestry to woody species conservation and management in Western Ethiopia

Abstract

Smallholder coffee-based agroforestry play an important role in conserving woody species and supporting broader ecosystem functions. Nevertheless, their contribution to woody species conservation has been insufficiently studied. The current study was therefore conducted to evaluate the contributions of smallholder coffee-based agroforestry for woody species conservations, compositions, management as compared to adjacent fragmented forests. Vegetation survey data were collected from 54 plots in smallholder coffee-based agroforestry and adjacent forests using 20 m × 20 m plots. Additionally, structured questionnaires were administered to 54 households to capture local knowledge and woody species management strategies. Results revealed that a total of 53 woody species representing 16 families were recorded and smallholder coffee-based agroforestry retained significantly (P < 0.05) 56% of forest species richness, 60–70% of diversity indices, and 84% of stem density. Shannon diversity was significantly (P < 0.05) lower in smallholder coffee-based agroforestry (1.55 ± 0.24) than in forests (2.55 ± 0.34), while evenness was higher in coffee-based agroforestry (0.94 ± 0.03 vs. 0.74 ± 0.06), indicating a more uniform distribution of retained species. Basal area was significantly higher in smallholder coffee-based agroforestry (10.89 ± 5.57 m2 ha⁻1) compared to forests (8.45 ± 3.47 m2 ha⁻1, P < 0.05), reflecting the retention of larger trees. Household interviews and key informant discussions confirmed that farmers actively manage and retain multifunctional shade trees—particularly for coffee shade (100%), income generation (91.4%), and soil fertility enhancement (80.65%). Management practices were dominated by pruning (88.9%), thinning (50%), hoeing (100%), and weeding (100%). The study concludes that smallholder coffee-based agroforestry act as secondary habitats and biodiversity reservoirs, complementing natural forests in landscape-level conservation. Farmer centered incentives could further maximize their conservation potential, ensuring that these agroforestry systems continue to support ecological sustainability while simultaneously improving rural livelihoods.