MALNUTRITION: Africa has good soils and could easily feed itself

Africa has good soils and could easily feed itself if more money was spent on fertiliser and seed rather than food aid, says one soil scientist.
World Food Prize Laureate Dr Pedro Sanchez laid out his argument to a recent agricultural research symposium at the University of Sydney.
"A lot of the public opinion still feels that Africa is a basket case. It cannot feed itself," says Dr Sanchez, of Columbia University's The Earth Institute in New York.
"I think that needs to change."
Expanding on a recent article in Nature Geoscience, Dr Sanchez argues tropical Africa is capable of tripling its crop yields if something is done about the lack of nutrients in its soils.
"Food crop yields have not changed in Africa since 1961," he says. "That's 50 years. It's amazing."
Dr Sanchez says most of the soils cultivated by Africa's small farmers are "pretty decent", but have become depleted of nitrogen, and to a lesser extent phosphorous.
"The soils are not inherently bad as some people have said," he says.
"What happened is that farmers took out too many nutrients, mainly in the form of crop harvests."
He says the same thing happened after 100 years of farming in the US Midwest, which has some of the best soils in the world.
While he sees GM crops as part of the solution to feeding Africa, Sanchez says the focus of donor agencies, like the World Bank, on improved crop varieties has missed the importance of soils.
"If the fertilisers aren't there, there is no way you can have high-yielding varieties reaching their potential," says Dr Sanchez.
Tripling yields
Dr Sanchez says an African green revolution can increase cereal grain yields from around 1 to 3 tonnes per hectare by 2020 and evidence to date suggests this is a reality.
"It's being done at sufficient scale now that we can say this not just an idea. This is reality," he says.
He says in 2005 Malawi's maize harvest only reached 57 per cent of the country's requirement, with about 5 million Malawians requiring food aid.
Dr Sanchez says since then, the government has begun subsidising farmers to buy fertiliser and improved maize seed.
In 2007, maize yields almost tripled at the national scale, transforming Malawi into a food exporter, he says.
Dr Sanchez says the subsidy programs are now being extended to another 11 countries in Africa including Tanzania, Kenya, Ethiopia, Uganda, Mali and Nigeria.
He says the gains in yield are similar to those seen in India and the Philippines at the start of the Asian green revolution.
By contrast, yields from highly-subsidised farmers in North America are around 10 tonnes per hectare.
Dr Sanchez says the canopy produced by higher-yielding plants will also reduce evaporation of water from the soil, helping farmers to better manage climate change-induced droughts.
'Organics'
Dr Sanchez says subsidies also need to be extended to organic fertilisers that contain carbon, feed soil microbes and help retain soil moisture.
He says the most effective of these are nitrogen-fixing legumes which have often been abandoned by farmers because of the cost involved in establishing them.
"When you plant those legumes they take some time to grow and usually farmers have to ... forgo a crop or so," says Dr Sanchez.
He says farmers should be paid for the opportunity cost of planting these crops, especially since they provide all kinds of "ecosystem services".
"It's a public good also because they also fix carbon from the air, they cut down on soil erosion," he says. "They increase soil organic matter."
He says while aid is important for people such as those who are starving refugees from war, 90 per cent of Africa's hungry are in rural areas.
Not only can food aid depress local prices, it costs six times more to feed people with food aid than by subsidising fertiliser and seed, says Dr Sanchez.
Dr Sanchez says greater funding for research into soils will be essential in developing sustainable agricultures.
"We know more about the soils of Mars than the soils of Africa," he says.
http://www.abc.net.au/news/stories/2010/06/10/2923356.htm