African Journal of Water Conservation and Sustainability

African Journal of Water Conservation and Sustainability ISSN: 2375-0936 Vol. 5 (5), pp. 206-220, May, 2017. © International Scholars Journals

Full Length Research Paper

Modeling the impact of water and nutrient management in African agriculture

Marco Pastori, Fayçal Bouraoui, Alberto Aloe

European Commission Joint Research Centre (JRC), Institute for Environment and Sustainability (IES), via E. Fermi 2749, I-21027 Ispra (VA), Italy.

*Corresponding auth: E-mail: [email protected] Tel: +390332785173

Accepted 4 February, 2015

Abstract

Africa has to adapt to the growing demand for agricultural commodities driven by growth in population, per capita income and new demands for biofuel. There is a wide agreement that African agriculture has enormous potential for growth and will shift towards a more productive farming. A systematic approach is needed to identify the main factors that explain observed yield gaps and to evaluate the impacts of a potential intensification on the environment. In this paper we presented a crop yield gap analysis for Africa using a newly developed tool linking a Geographic Information System and the biophysical model EPIC. We showed that in most African countries, the main limiting factor to crop production is nitrogen, while water limitation is more restricted to few countries. The predicted yield gap is much more marked in Sub-Saharan Africa than in North Africa. We predicted that a mining of soil resources, with nitrogen crop uptake exceeding the inputs through fertilization, is taking place in many countries in Africa. We also showed that even in water rich countries, appropriate water management including the development of irrigation infrastructure is needed to close the yield gap.

Key words: Water management, nitrogen requirements, irrigation requirements, yield gap, Africa, Epic.