How to feed 1 billion more people in 2050
In 2050, Africa is estimated to have nearly 1 billion more people than in 2020.[1] Africa will need to produce more food, feed, fibre and (bio-)fuel to satisfy the needs of all its inhabitants. In 2050, African water resources are expected to be under greater stress compared to 2020. Rainfall is the major source of water for food production currently in Sub-Saharan Africa. Despite the uncertainty about the future climate, most experts agree that in 2050 rainfall will be more erratic: rainfall events will be more intensive and dry spells during the rainy season are likely to be more frequent and longer.[2]
Agriculture in sub-Sahara Africa currently produces well below its potential. This is attributed to several issues, of which two stand out: erratic rainfall and sub-optimal fertilizer use. The majority of African farmers with rainfed plots do not apply fertilizer, or far too little.[3] Uncertain rainfall means uncertain harvests,[4] explaining the reluctance of farmers to invest in inputs. As a result, average crop yields are far below the potential (around 1.5 to 2 tons per ha for grains) and have been nearly stagnant for the last 30 years.[5] At least 15% of all arable land in sub-Saharan Africa is semi-arid to arid (300-600 mm/yr) and host 150 million people. Here, as many as half of all rainy seasons may result in serious crop yield reductions or even total crop failure. The majority of rural livelihoods in these lands are vulnerable and fragile.
Combining population growth, climate change, and current agricultural production numbers, paints a challenging future. Low crop yields imply that there is significant scope for doubling or even tripling these. This is the good news. Also, there are opportunities and potential solutions that may trigger an advancement in farmer-led irrigation in certain regions and climate zones where sand rivers are present. Enhancing access to water storage during dry spells and during the dry season could boost production year-round as farmers, once confident with sufficient water to harvest a decent crop, are willing to invest in inorganic fertilizers, improved seeds, higher value crops etc.
Finally, farmer-led irrigation has been put higher on the international water agenda, for example as part of the Kigali Joint Statement on Inclusive and Sustainable Farmer-led Irrigation at the 2018 African Green Revolution Forum conference, and the World Bank and Global Water Security & Sanitation Partnership (GWSP) initiative on farmer-led irrigation.[6]
[1] UN, 2017, https://www.un.org/development/desa/publications/world-population-prospects-the-2017-revision.html
[2] E.g. for southern Africa: Conway et al., 2015, http://dx.doi.org/10.1038/nclimate2735;
Fant et al., 2015, https://doi.org/10.1007/s10584-014-1314-x [open access];
Pinto et al., 2015, http://doi.org/10.1007/s10584-015-1573-1.
[3] Mueller et al., 2012, www.nature.com/doifinder/10.1038/nature11420;
Lu and Tian, 2017, https://www.earth-syst-sci-data.net/9/181/2017/ [open access]
[4] Van der Zaag, 2010, http://www.water-alternatives.org/index.php/volume3/v3issue1/76-a3-1-9 [open access];
Bossio et al., 2011, http://dx.doi.org/10.1016/j.agwat.2011.07.006
[5] Mueller et al., 2012, www.nature.com/doifinder/10.1038/nature11420
[6] Wiggins and Lankford, 2019, https://www.odi.org/publications/11394-farmer-led-irrigation-sub-saharan-africa-synthesis-current-understandings