Woody plant species diversity as a predictor of ecosystem services in a social–ecological system of southwestern Ethiopia

Context Human-dominated landscapes in the tropics need to be managed for biodiversity and the maintenance of ecosystem services (ES). Nevertheless, integrating both biodiversity conservation and ES management remains a challenge. Objectives This study aimed to quantify woody plant species diversity and associated ES in farmland and forests, and investigate the relationship between species and ES diversity. Methods The study was conducted in southwestern Ethiopia. We surveyed woody plants in 181 20 m by 20 m plots in farmland, forest with, and forest without coffee management. We also interviewed 180 randomly selected households about woody plant benefits. We then (a) quantified species and ES diversity; and (b) investigated the relationship between species and ES diversity. Results We recorded 128 woody plant species in total. Most ES were available in all land uses, although they differed in their mean availability. ES composition was significantly different among land uses. ES diversity was positively related with species diversity in all land uses. Conclusions Our findings suggest that all examined land-use types were multifunctional in terms of key ES provided by woody plants and that maintaining high species diversity also benefits ES diversity. Given these findings, we suggest to: (1) strengthen landscape multifunctionality by drawing on the positive relationship between biodiversity and ES diversity; (2) devise conservation policies that encompass entire landscape mosaics and enhance co-benefits of conservation and ES provision across land uses; and (3) conduct further social–ecological studies that use mixed data to elicit socially relevant relationships between biodiversity and ES diversity.