Identification of Optimal Agricultural Development Strategies in the West African Sahel Mékrou Transboundary River Basin

Mekrou is a transboundary river basin across Benin, Burkina Faso, and Niger. In this area, agricultural production plays a major strategic role in guaranteeing household food security for the sustainable development of the basin. Increasing agricultural productivity is crucial for meeting the growing population demands. Climate change (CC) is already affecting agricultural production due to increased frequency and intensity of extreme weather events. In this paper, a systematic approach to identify the main factors that influence observed yield gaps and to evaluate the impacts of agricultural intensification on the environment and support local development plans is presented. By using a newly developed decision support system tool (E-Water) linking a geographic information system with the biophysical model EPIC, we demonstrate that the agricultural sector has a growing potential by adopting more integrated and efficient agricultural production systems. The analysis of the crop yield gap shows that the main limiting factor for crop production is low soil fertility, while water is limiting during dry years. We predict that the adoption of more intensive farming techniques and sustainable irrigation practices can increase the capacity of agriculture to efficiently mitigate the impacts of climate change and other external environmental stress factors. We confirm that irrigation can substantially increase yield and that it will be required to adapt to expected climate and increase of rainfall variability.