Skip to main content

Freshwater for food production in tropical Africa


Globally, around 70% (and up to 95% in some developing countries) of freshwater withdrawals are used for the purpose of agriculture (FAO, 2017) – the chief driver of water stress. Studies show that 57% of global freshwater use for crop production is unsustainable (Mekonnen and Hoekstra, 2020). This highlights the significance of employing appropriate methods of irrigation to sustain efficacy of food production during periods of hydrological variability. Countries of tropical (broadly sub-Saharan) Africa, reportedly, irrigate only around 5% of cropland, predominantly on a small scale basis. This is due to dependence on rain-fed agriculture (Xie et al., 2021). Rainfall is plentiful in tropical Africa, particularly in the ITCZ, but climate change makes the rainfall patterns erratic and leaves those regions vulnerable to drought. 

 

        (top and bottom image) Entoto Hill, Ethiopia. Source: Trip.com 


There exist risk-averse strategies for rain-fed agriculture which focus on practices that make use of the climatic and hydrogeological variability. While irrigation is usually discussed in the context of overexploiting water reserves, small-holder farms’ irrigation could help to replenish the resource. The case of the ‘Bengal Water Machine’ (Shamsudduha et al, 2022) illustrates how groundwater withdrawals for irrigation in the dry season can create the conditions for efficient recharge during the wet reason’s rain-fed cultivation. 

 

It's downhill in Ethiopia

In Oromia, Eastern Ethiopia people have adapted their types of agricultural cultivation of crops and livestock based on the changing nature of freshwater access at different elevations. Shallow uphill aquifers suffice for predominantly rain-fed cultivation of potato and cereal grains. On hill slopes, people dig wells and boreholes, extracting enough water to permit irrigated cash crops such as chat, while downhill groundwater rich fields sustain livestock rearing (Tucker et al., 2014).



       Oromia, Ethiopia:  (a) Map of area used in the study (b) Illustrative cross-section of the study transect, showing elevation, hydrogeological characteristics, and typical water sources. Source: Tucker et al., 2014. 


We'll just have tap water for the table, please

Examining freshwater for food production involves that which is counted as domestic withdrawals. Groundwater provides over 80% of rural domestic supply in tropical Africa (Calow et al., 2010). Access to food and water is interrelated, however, decline in water access rarely indicates water scarcity. People, first, extract by hand from shallow water sources. Once those run low, tool-aided, deeper extraction eventually becomes limited by mechanical issues, which often go unaddressed for extended periods of time (Calow et al., 2010). Not all groundwater stores are rechargeable or encourage fair distribution of water access, which can lead to disputes, but this idea will be explored in a later entry. In Ethiopia, 64% of rural households depend on surface water (Tucker et al., 2014) which is inherently very prone to contamination.

 

Domestic water is used for cooking and meal preparation, hence the quality of it is important. Evidence from the town of Lukaya, Uganda show that around 55% of the shallow water sources, considered ‘improved’ and, therefore, safe for consumption, are contaminated with E.coli bacteria and faecal matter (Nayebare et al., 2020). Water contaminants permeate all aspects of life; boiling does not render them harmless, meaning they are consumed in home meals and drinking water. The water that mother ingests is used for production of breastmilk, the food for her baby, and can cause disease (McMahon et al., 2013). African countries are not amongst the most unsustainable freshwater users (Mekonnen and Hoekstra, 2020), yet, they vastly suffer safe water shortages and the repercussion of it.  
















Comments

Post a Comment

Popular posts from this blog

Integrated water management for food security

' Water is both an indispensable input and a key constraint ' .   As illustrated in previous entries, the current water condition in Africa, as it pertains to food production, needs more efficacy in water management, and increasingly so, due to climate change effects on hydrology. Expansion of irrigation, particularly groundwater, could be an effective adaptive strategy for the growing population. However, inherent hydrological inequalities pose great challenges and droughts threaten rain-fed livelihoods where potential for irrigation is limited. There exist methods of enhancing rain- fed productivity but they employ temporally and water quality sensitive approaches which are difficult to maintain.          (top)  Farming in Western Sahara; Source : Getty Images; (bottom) half-moon dam/swales in a field, used to save water during rainfall, Burkina Faso; Source : FAO. What’s the matter (and why does it matter)? Drylands of tropical Africa contain 50% o...
2 comments
Read more

Introduction to the blog

Food production is intrinsically linked to water – when agricultural water supply or access dwindle, or dip suddenly, food security follows the trend soon after ( World Bank, 2020 ).  Sustainable Development Goal (SDG) 2, focusing on expanding global food security, has brought about intensive initiatives, which demonstrate the critical need for irrigation for food production globally. Agriculture across Africa is dominated by smallholder farmers, which make up some 60% of Sub-Saharan population and even more in other regions. Implementing SDG2 will require as much as 65 billion dollars in irrigation alone ( Goedde et al., 2019 ).              Colocynth fruit growing in the Sahara;  Source : Britannica.  African realities  will draw on case studies from across the nations of the continent and report the figurative good, the bad and the ugly of water, as it pertains to food production. Africa is well suited for exploration of this to...
Post a Comment
Read more

African voices on the global climate arena - COP27

Global climate change influences freshwater availability and demand in Africa. This short entry briefly summarises the  African realities  of food systems as described in a  UNFCC report  prepared for Conference of Parties (COP27) in Sharm el-Sheikh, Egypt, with author list featuring prominent African experts.       COP 27 sign; Source : Scientific American Cry me a river - would water solve all problems? The report critiques the preoccupation with food production, as has also been my own focus in this blog, and calls for close consideration of other aspects of food security such as storage, processing, distribution and consumption. Rapid population growth and increasing urbanisation across the continent will also have collateral impacts on water in food systems and hence food security.  The previous entry already outlines the nexus of climate change, water, and food production, largely citing this report.  What do Africans think they need...
Post a Comment
Read more