Strategies to increase biodiversity at the farm and landscape level in East Africa

Smallholder farmers in East Africa face intensifying climatic and agronomic challenges, including increasingly erratic rainfall, heat stress, and degraded soils. In this context, Nature-based Solutions (NbS) that enhance biodiversity and agroecosystem functioning at both farm and landscape scales are becoming critically important. We evaluated two farmer-led NbS: conservation agriculture (CA)—minimal soil disturbance, diversified cropping, and soil cover—and farmer-managed natural regeneration (FMNR), a landscape-scale practice that restores degraded land from over-grazing, excessive tillage, and deforestation. Across seven years of on-farm CA adoption on 90 farms across variable agroecological zones in Kenya and Ethiopia, we observed consistent improvements in soil health and biodiversity relative to conventional agricultural practices. CA increased aggregate stability, microbial respiration, infiltration capacity, and soil organic carbon, with the strongest gains in clay-rich soils. Beneficial and neutral insect diversity were also higher under CA, suggesting broad agroecosystem benefits. Farmer-based indicators (hoe test, infiltration scores) closely mirrored laboratory measurements, highlighting their utility as low-cost, scalable monitoring tools. Importantly, many farmers continued CA practices after project completion, citing reduced labour, lower reliance on purchased inputs, and improved yield stability. At landscape scales, FMNR data from a semi-arid Kenyan site showed that FMNR substantially increased soil carbon stocks. Across 25 FMNR fields, soil carbon was significantly higher than in neighbouring conventional sites, while soil infiltration and microbial activity trended positively. Insect abundance and diversity did not differ between FMNR and conventional farms, though this system may take more time to recover. Taken together, these results show that CA and FMNR operate as complementary NbS: CA enhances on-farm soil function, in-field biodiversity, and climate resilience, while FMNR rebuilds woody and herbaceous cover and stores large amounts of carbon at landscape scales. Integrating these approaches can provide a powerful pathway for restoring agroecosystem biodiversity, strengthening smallholder livelihoods, and improving long-term sustainability under a changing climate.