Dilemma of nitrogen management for future food security in sub-Saharan Africa – a review
Cargele Masso A B H , Fredrick Baijukya C , Peter Ebanyat D , Sifi Bouaziz E , John Wendt F , Mateete Bekunda G and Bernard Vanlauwe A
+ Author Affiliations
- Author Affiliations
A International Institute of Tropical Agriculture, PO Box 30772, Kasarani, Nairobi, Kenya.
B Africa Regional Center of the International Nitrogen Initiative, PO Box 30772, Kasarani, Nairobi, Kenya.
C International Institute of Tropical Agriculture, PO Box 34441, Mikocheni, Dar es Salaam, Tanzania.
D International Institute of Tropical Agriculture, PO Box 7878, Naguru, Kampala, Uganda.
E Institut National de la Recherche Agronomique de Tunisie (INRAT), Rue Hédi Karray 2080, Ariana, Tunisia.
F International Fertilizer Development Center, PO Box 30772, Kasarani, Nairobi, Kenya.
G International Institute of Tropical Agriculture, PO Box 10, Duluti, Arusha, Tanzania.
H Corresponding author. Email: C.Masso@cgiar.org; mcargele@gmail.com
Soil Research 55(6) 425-434 https://doi.org/10.1071/SR16332
Submitted: 19 January 2017 Accepted: 8 June 2017 Published: 13 July 2017
Journal Compilation © CSIRO Publishing 2017 Open Access CC BY-NC-ND
Abstract
Food security entails having sufficient, safe, and nutritious food to meet dietary needs. The need to optimise nitrogen (N) use for nutrition security while minimising environmental risks in sub-Saharan Africa (SSA) is overdue. Challenges related to managing N use in SSA can be associated with both insufficient use and excessive loss, and thus the continent must address the ‘too little’ and ‘too much’ paradox. Too little N is used in food production (80% of countries have N deficiencies), which has led to chronic food insecurity and malnutrition. Conversely, too much N load in water bodies due mainly to soil erosion, leaching, limited N recovery from wastewater, and atmospheric deposition contributes to eutrophication (152 Gg N year–1 in Lake Victoria, East Africa). Limited research has been conducted to improve N use for food production and adoption remains low, mainly because farming is generally practiced by resource-poor smallholder farmers. In addition, little has been done to effectively address the ‘too much’ issues, as a consequence of limited research capacity. This research gap must be addressed, and supportive policies operationalised, to maximise N benefits, while also minimising pollution. Innovation platforms involving key stakeholders are required to address N use efficiency along the food supply chain in SSA, as well as other world regions with similar challenges.
Additional keywords: eutrophication, innovation platform, land degradation, nitrogen use efficiency, policy, quality standards.
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