Assessing climate-smart agroforestry practices: a study of tree species composition, distribution, and utilities in two contrasting agroecosystems of Rwanda

Abstract

Tree adoption on farms has expanded around the world in the last years due to food security concerns and is expected to further spread due to climate change. Climate-smart agroforestry (CSAF), a smart farming approach, is one of these farming patterns. In this study, we (a) analyzed the distribution and composition of trees in CSAF systems, (b) assessed tree diversity in CSAF systems, (c) analyzed CSAF best management practices, and (d) evaluated CSAF-derived utilities in two contrasting agroecological zones of Rwanda. In particular, species composition, diversity, richness, evenness, and similarity were estimated across land use types. Utility data were recorded as fulfilled goals from different practices. Home gardens, alley cropping, improved fallow, multipurpose trees, plantation crop combination, shelterbelts/windbreaks, and silvopasture are the predominant CSAF practices in Bugesera and Rulindo with different structures and compositions. Results highlighted that tree species diversity, richness, dominance, and importance decrease from Rulindo to Bugesera (H′ = 1.397–1.247), (Dmg = 0.621–0.368), (D = 0.192–0.117), (IVI = 58.42–58.02). Moreover, farmers seemed to give more weight to utilities from goods meant for household survival such as fruits (home consumption), fuelwood (culinary), fodder (cattle-housed for zero-grazing), and standing trees (stakes for climbing crops). Logs, and poles/timber meant for commercial purposes were given the least weight. Introducing and upscaling fruit tree species on farms can be one of the best alternatives to improve local climate-resilient landscapes and livelihoods. The outcomes of this study can support the targeting of agricultural interventions and innovations in resource-poor settings struggling with food security challenges.