A recent research study concludes that the path to cereal self-sufficiency for countries in sub-Saharan Africa (SSA) will require, in addition to yield gap closure, increased cropping intensity and expansion of irrigated production area in regions that can support these options in a sustainable manner.
The study projects a two- to four-fold increase in population and estimates cereal demand to triple for the 10 countries studied by the year 2050. However, trends show that all countries, except Ethiopia and Zambia, have cereal yields growing more slowly than population and demand. For example the maize yield increase averaged only 27 and 34 kg per ha per year in west and east SSA countries respectively. Attaining self-sufficiency would necessitate doubling the yield increase. This is elusive in SSA where farmers lack access to markets; and to seeds, fertilizers and pest management inputs to support
Without yield increase, the demand for cereals can be met through crop area expansion or imports or both. Current levels of cereal consumption already depend on substantial imports while crop area expansion comes from deforestation and converting marginal land or previously abandoned crop land as the experience of crop land expansion in Ethiopia and Tanzania show.
Apart from yield increase on existing farmland, other possibilities are to increase cropping intensity (more crop cycles per year on the same field) and to increase the amount of irrigated area where water resources are available.
“There are still possibilities to grow multiple crops per year and to expand the irrigated area, but these are options with many uncertainties,” according to Prof Dr Martin van Ittersum, Principal Investigator of this research study.
If those fails, major expansions of farmland are required which will be at the cost of natural habitats and increased greenhouse gas emissions, or enormous grain imports that must be paid with scarce foreign exchange. However, in some countries, the required area is simply not available, and expansion of farmland is not sustainable, explains co-researcher, Prof Dr Abdullahi Bala.
Although the research was conducted for 10 SSA countries, the study considers it unlikely that the situation is more favorable in other African countries as the availability of arable land per capita is comparatively lower.
The research was conducted using agronomically relevant local data and spatial upscaling protocol to estimate food production capacities in five staple cereals namely maize, millet, rice, sorghum and wheat. The estimations are specific to 10 SSA countries: Burkina Faso, Ghana, Mali, Niger, Nigeria, Ethiopia, Kenya, Tanzania, Uganda and Zambia.
The yield gap analysis is the result of research undertaken by a team of researchers from Wageningen University & Research, several African institutes and the University of Nebraska.
This comprehensive research is based on the collaborative work undertaken in the Global Yield Gap Atlas (GYGA) project, coordinated by Dr Lieven Claessens, Principal Scientist – Resilient Dryland Systems, ICRISAT-Nairobi.
For more information on the GYGA project click here
Research findings from this study have been published in the journal, Proceedings of the National Academy of Sciences of the United States of America (PNAS): van Ittersum MK, van Bussel LGJ and Wolf J et al. 2016. Can sub-Saharan Africa feed itself? PNAS, Early Edition http://www.pnas.org/content/early/2016/12/07/1610359113.abstract