Climate resilience of irrigated quinoa in semi-arid West Africa

Abstract

Quinoa (Chenopodium quinoa Willd.) is a herbaceous C3 crop that has demonstrated resilience in regions concurrently affected by climate change and food insecurity, such as sub-Saharan Africa (SSA). The photosynthetic rate and productivity of C3 crops are enhanced under increasing CO2 concentrations. We looked at future climate trends in SSA to estimate their impacts on quinoa yields in Burkina Faso. Climate projections show a temperature increase of 1.67-4.90°C under Representative Concentration Pathways (RCP) 4.5 and 8.5, respectively by the end of the century. We demonstrate that any further climate disturbances can either be beneficial or harmful for quinoa, and modulating climate risks will depend on the decisions made at the farm level (e.g. planting date and crop choice). Crop modelling supports the identification of the most suitable transplanting dates based on future climate conditions (RCP 4.5 and 8.5), agroclimatic zones (Sahel, Soudano-Sahelian and Soudanian) and time-horizons (2020, 2025, 2050 and 2075). We show that quinoa yields can improve—when grown under irrigated conditions and transplanted in November—by about 14-20% under RCP 4.5 and by 24-33% under RCP 8.5 by 2075 across the Sahel and Soudanian agroclimatic zones, respectively. For the Soudano-Sahelian zone, the highest yield improvements (19%) are obtained when transplanting is assumed in December under RCP 8.5 by 2075. Overall, the findings of this work encourage policymakers and agricultural extension officers to further promote climate-resilient and highly nutritious crops. Such possibilities are of much interest in SSA, thought to be highly vulnerable to climate change impacts where millions of people are already experiencing food insecurity.