The Herald (Zimbabwe)

Africa’s fertiliser shortages require continenta­l solutions

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AFRICAN presidents met in Nairobi for the Summit on Fertiliser­s and Soil Health, a technical, but exceptiona­lly important topic since many of the solutions, especially to double and triple fertiliser output, will require collaborat­ive efforts.

Zimbabwe has been expanding agricultur­al production, and soil conservati­on, fairly rapidly under the Second Republic, largely by looking at new farming techniques based around conservati­on agricultur­e, with the Pfumvudza/Intwasa programme for small-scale farmers leading the way, and by ensuring that farmers get enough fertiliser in their inputs.

A major stress in the Zimbabwean programmes is to get maximum benefit from fertiliser­s, which conservati­on farming gives. The idea is to have far more intensive farming, with soils being built up at the same time, on the same area or even less that used to be planted under older and less-efficient systems.

But Zimbabwe is fairly typical of all African countries in that it has to import a lot of fertiliser. While the country has phosphate reserves, and is expanding the mining of these, there are zero potassium minerals that can be mined and ammonium nitrate fertiliser­s rely on importing 80 percent of requiremen­ts, with even the local production relying on imported raw materials.

Most of the world’s potassium fertiliser­s come from just four countries: Russia, Belarus, China and Canada that have the right geology, with potassium minerals laid down 50 to 100 million years ago in shallow seas on continenta­l shelf.

Africa, generally as a continent, was pushed together as a set of cratons a very long time before that and so never really had much in the way of the suitable shallow seas. South America, the Indian subcontine­nt and Oceania are in the same position, having split off from Africa.

But there are some potash deposits in Africa. Republic of Congo, that is Congo Brazzavill­e, Morocco, Eritrea, bits of Ethiopia and bits of Egypt have such deposits, so there are African sources, although many of these still need to be mined.

Ammonium nitrates, these days, are largely made from ammonia generated from natural gas, and there are a number of African countries that have such gas deposits, with Zimbabwe latest on the list following the Muzarabani strike.

There is a second source, that Zimbabwe used when Kariba could generate more power out of peak periods than could be sold.

This involves the liquefacti­on of air to obtain nitrogen and the electrolys­is of water for hydrogen. But that method uses a lot of electricit­y and, unless there is a huge surplus of very cheap renewable energy, the resulting fertiliser will be very expensive.

Norway, with its surplus of hydro, does make ammonia this way, but it is not at present a solution for Africa.

So while no African country actually has all the main ingredient­s of modern fertiliser­s, the continent as a whole has the lot, or at least the building blocks that make up the lot.

Of course there are the intermedia­te industrial stages to turn potassium ores into the potassium salts that farmers want in a bag, and the natural gas first into ammonia and then into the ammonium nitrate salt that again farmers need in a bag.

Even the fairly concentrat­ed phosphate deposits found in Zimbabwe and a few other countries need to be processed between the mines and the bag.

Turning raw materials into bags of fertiliser will require very large investment­s across a number of countries.

This is one reason why a Presidenti­al-level summit is required. The technical experts can give the total supplies required, and they can also tell the presidents where African raw materials exist and how they can be processed into simple and compound fertiliser­s.

But it will need the political directives to ensure that a continenta­l business is built up, with the countries that have the natural resources feeding their inputs into a continenta­l pool that all draw down on for their national needs.

It is possible, but will require a high level of coordinati­on, excellent contacts between the fertiliser businesses across the continent, and fairly careful direction of investment.

While fertiliser raw materials can be imported from other continents, and at the moment are imported, Africa needs to work towards self-sufficienc­y. Conflict, the need for exporting countries to use more on their own territory and other potential squeezes in supply require Africa to be largely self-sufficient.

This is particular­ly so when we consider that the agricultur­al experts reckon that Africa only uses a modest percentage of the fertiliser that should be used.

A huge expansion in use could well strain present global supply lines, hence the need for Africa to create its own internal supply lines from its own resources.

Finding enough fertiliser for all African farmers could well place intolerabl­e strains on global supplies unless Africa builds up its share of global production.

As a continent we also need to make sure that while there are adequate supplies of fertiliser­s for modern farming, we waste nothing so we do not contaminat­e land, do not spend more than we need to produce our food, and we do not lose our topsoil.

A lot of this is applying research to farming, testing out new techniques and then creating best practices.

The conservati­on systems used in Pfumvudza are considered a best practice, but research and innovation must continue to be stressed so that something better still can be developed, or at least the conservati­on farming systems can be improved and tweaked.

We cannot sit still. We have to move forward.

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