Denis Mpairwe

Feed scarcity and land degradation are major constraints to livestock production in the drylands of Sub-Saharan Africa (SSA). This systematic review assessed the most commonly studied grass and forage legume species and how grass–legume mixtures affect forage yield and nutritive value in SSA drylands. Following PRISMA 2020 guidelines, Web of Science and Scopus were searched for peer-reviewed studies. A total of 32 studies met the inclusion criteria, covering ten countries, with most studies conducted in Kenya, Nigeria, Tanzania, and Ethiopia. The review identified 91 forage species (55 legumes, 36 grasses), with Centrosema pubescens and Chloris gayana being the most frequently studied legume and grass species, respectively. Of the 20 studies reporting dry matter yield in grass–legume mixtures, 17 (85%) showed increases of 13–500% compared with grass monocultures, while three (15%) reported decreases of 2–37%. Nine studies compared forage nutritive value, with reported crude protein of mixtures ranging from 9.6% to 14.4% of DM. The evidence base was limited by substantial heterogeneity in species combinations, management practices, the small number of contemporary studies, and limited assessment of socio-economic factors influencing adoption. Further research should prioritize long-term, participatory and farmer-managed evaluations across contrasting environmental and socio-economic contexts.

Drylands face urgent development challenges that are complex and interconnected, requiring holistic systems-based approaches. Here, we present a social–ecological systems framework to guide research, policy, and action across disciplines and sectors towards sustainability transformations in drylands for improved livelihoods and enhanced ecosystem, livestock, and human health. Our conceptual framework integrates three non-exclusive and complementary lenses of human-driven transformations: systemic, structural and enabling/grassroots change. Based on these three complementary lenses, along with three main phases of transformation and key associated actions, we briefly illustrate the framework’s value through the case of the Karamoja cross-border region of East Africa. We show how the framework can be used as an entry point to identify and analyse key challenges and their interlinkages; envision desired social–ecological systems; and explore pathways towards sustainability. The framework provides actionable guidance to co-develop context-specific interventions that support sustainability transformations in drylands.