For Ivan Altchenko, research professor on the Montpellier campus of AgroParisTech, the problem of food security on the African continent is an infrastructure problem, but it is also a problem specific to sub-Saharan Africa.
In Africa, surface and groundwater irrigation has not been fully developed. Currently, only 6% of cultivated land is irrigated while in Asia we are already at 40%, explains Yvan Altchenko. For 50 years great efforts have been made on the African continent but we are still below what exists in other regions of the world. In underdeveloped countries, investors are needed to deploy infrastructure, but they have lost interest in the African continent for several reasons.
First of all, the performance of the public irrigation systems was poor. In the 1980s, the price of cereals fell, which made African production very uncompetitive in the face of competitors, particularly in relation to subsidized production from which benefit certain countries. Added to this is political, social and environmental instability, as well as poor management of existing projects.
Yvan Altchenko believes that agricultural production must be developed to limit this food insecurity. But irrigation with groundwater is, according to him, a good way to optimize agriculture on the continent.
“Groundwater has several advantages. It is a safe and reliable resource.”Yvan Altchenko
All observations show that there are large underground water reserves in Africa, even if they are more or less accessible. The engineer also explains that irrigation with groundwater can increase yields because the system promotes the development of new agricultural practices with the addition of fertilizers in particular.
“The mode of groundwater use is also much more flexible because it is independent of drought” continues Yvan Altchenko who explains that there is always a “buffer” effect with groundwater.
When we are in the middle of a drought there is still water at great depths, so it is an interesting resource for irrigation. The specialist recognizes, however, that it is necessary to make joint use of groundwater, surface water and the reuse of wastewater.
At present, it is estimated that there are 20 million hectares in Africa that could be irrigated by groundwater. On these 20 million hectares, there are areas where groundwater irrigation is already at its maximum, therefore unusable under penalty of weakening the resource. This is the case for the whole part of the Maghreb and South Africa. On the other hand, in areas where it is possible to act, it is estimated that production could be increased by 75%.
The whole question is to know to what extent we can exploit these underground waters without harming the resource. According to Yvan Alchenko, little is known about groundwater.
“We don’t know the exact storage, nor the mechanisms that allow the recharging of this resource, as well as all the interactions around it.”
Groundwater in the ground is an important source for rivers and wetlands, which is why it is important to master its operation and accurately assess the amount of water that can be used without weakening the resource. According to the researcher, preference should be given to renewable groundwater that receives regular water recharge.“Recharge is the amount of water that infiltrates the ground to reach aquifers”, he said. This water recharge must therefore be high enough to maintain the water levels in the aquifers according to withdrawals.
Yvan Altchenko insists on the fact that groundwater is used to supply rivers and wetlands, but also agriculture, livestock, not to mention industry and domestic use. The use for agricultural uses is a tiny part of the needs but it has important consequences for food security which is one of the priorities on the African continent.
“Improved irrigation management would increase agricultural production by 75% in Africa.”Yvan Altchenko
According to Yvan Altchenko, there are several ways to improve food security in developing countries. We can import food or promote access to foodstuffs with subsidies, but we can also increase agricultural production.
Groundwater is therefore, according to him, a way to increase this agricultural production with improved management of irrigation. A production increase of more than 75% could therefore be an effective lever for improving the food security of suffering countries.