Minimum emission pathways to triple Africa’s cereal production by 2050 (November 2019)
Martin K. van Ittersum, Renske Hijbeek, Hein ten Berge, Marloes van Loon, Hendrik Boogaard, Kindie Tesfaye
Demand for five cereals (maize, millet, rice, sorghum and wheat) is projected to increase between 2015 and 2050 by a factor 2.8 in subSaharan Africa (SSA) due to population increase and dietary changes.
To meet this demand, SSA could achieve selfsufficiency in 2050 using existing cereal cropland area, but only just so. Yields would have to increase between 2015 and 2050 from current levels, which are about 20-40% of the agronomic yield potential under rainfed conditions, to ca. 80% of that potential. This is an unprecedented rate of yield increase for rainfed systems in the world.
To enable the required yield increases, crop nutrient requirements will have to increase enormously, to - for example - an average minimum requirement of 140 kg nitrogen (N)/ha for maize, which is the most widely planted cereal in SSA. This is equivalent to a 15-fold increase between 2015 and 2050.
If cereal demand will be fulfilled in SSA, by 2050, greenhouse gas emissions from cereal production will be at least 50% higher than in 2015 due to the larger production, regardless whether scenarios of intensification or crop area expansion will be followed.
Intensification of cereal production with sufficient and efficient use of fertilizers will lead to lowest GHG emissions, but requires excellent agronomy, including the use of well-adapted cultivars, proper planting densities, good nutrient management and crop protection against weeds, pests and diseases.