Promoting Climate-Smart Agriculture Through Water and Nutrient Interactions Options in Semi-arid West Africa: A Review of Evidence and Empirical Analysis

In this paper, we analysed the ability of a range of existing technologies and practices and explored how their outcomes are linked to climate change adaptation and mitigation in West Africa. The rapid population growth alongside poor land use and management resulted in soil and water erosion, desertification, and salinization, creating a spiralling decline in the productivity of the land for food and other ecosystem services. Climate change brings additional threats arising from stresses and shocks caused by higher temperatures and lack of rainfall. Thus, farmers need to utilize agricultural strategies that sustainably increase productivity, resilience, while reducing GHGs emissions where possible. In order to implement such climate-smart agriculture options in semi-arid West Africa, water has to be available for crop nutrient uptake in the right amounts and at the right time, as water stress during plant growth results in major yield reductions for most crops. Also, farmers need to use more inorganic fertiliser, while striking the right balance between managing soil organic matter, fertility and moisture content and the use of fertilisers. The most successful systems are those that provide water, nutrients and a supportive soil structure in a synergistic manner. Indeed, we found that technologies such as zaï, half-moons, stone bunds combined with application of organic/inorganic sources of nutrients, are promising climate-smart agriculture practices that could be widely used by smallholder farmers to maintain food production and secure farmers’ livelihoods, while possibly protecting the environment. These successful examples can serve as inspiration for future policies and investments that pursue food security goals at all scales