Conservation agriculture assists smallholder farmers and their agroecosystem in the Democratic Republic of the Congo

Conservation agriculture, a sustainable farming practice combining no or minimum soil disturbance, crop diversification, and soil cover, can benefit humans and the biophysical environment. However, less than half of Sub-Saharan African countries implement conservation agriculture, and the majority of smallholder farmers are using unsustainable practices. Research and field trials on conservation agriculture adaptation to soil and agroecological conditions are vital for increasing adoption of conservation agriculture in Sub-Saharan Africa. The objectives of this study were to (i) evaluate the change in soil chemical properties and soil biology from implementation of conservation agriculture, (ii) assess cowpea (Vigna unguiculata L. Walp.) yield and variability under conservation agriculture compared to the conventional farming practice, and (iii) evaluate differences in soil chemical properties, soil biology, and crop yields under conservation agriculture in savannah and forest ecosystems compared to conventional agriculture in smallholder farming in the province of Maniema in the Democratic Republic of the Congo. Soils under conservation agriculture had 6.5 times more (p < 0.001) earthworms, 23% and 10% greater (p < 0.05) concentrations of soil phosphorus and potassium, respectively, and 100% greater (p < 0.001) cowpea yield than soils under conventional agriculture. Measured across all sites, conservation agriculture and conventional cowpea yields had coefficients of variation of 25% and 16%, respectively. This study showed for the first time that conservation agriculture implementation contributes to soil health and food security associated with smallholder farming in the Democratic Republic of the Congo.