POPULATION AND ENVIRONMENT ISSUES
Farming the Desert Margins
Article by Fred Pearce and Vesselin Voltchev (UNEP)
n the Kenyan district of Makueni, farmer Jane Ngei built her own dam with an ox-plough, spade and wheelbarrow. "It collects the water running down the road after it rains," she says. With a bucket and a perforated hose pipe she then uses the water to irrigate her couple of hectares of vegetables, maize and fruit trees in the dry season. The extra harvest is enough to feed her family and pay for her children to attend school. Of such things are agricultural revolutions made.
The story calls into serious question some of the more Malthusian predictions about fast-growing populations in the arid regions of Africa causing a near-inevitable advance of deserts. Makueni shows it does not have to be like that. In reality, farmers are finding ways to intensify their farming methods and feed their growing families without destroying their soils. In places, the sands are actually retreating -- even where rainfall is in decline.
Nor is Makueni unique. Take the dusty and densely populated region around Kano in northern Nigeria -- so heavily farmed it is called the "Kano close-settled zone". Here farmers are planting cowpeas alongside maize in their fields, and tethering sheep and goats to gather manure for spreading on the fields. Result: more fertile soils and bigger crop yields without the use of chemicals or cash.
"This zone has supported intensive cultivation without suffering land degradation. The integration of crops and livestock enhances nutrient recycling," says Frances Harris, a soil scientist from Kingston University, London. And far from high population density being a liability, it actually helps the process by supplying labor to feed animals, spread manure and work the fields.
B.B. Singh from the Kano office of the International Institute of Tropical Agriculture, who has pioneered these techniques, says: "We can double yields here easily and improve the environment at the same time. We can do it all over Africa."
David Niemeijer from Wageningen University in the Netherlands has seen much the same thing in eastern Burkina Faso. A geographer, he went there in the mid-1990s to measure land degradation as populations grew and rainfall diminished. But he has found "no evidence of land degradation, nor any decline in farm productivity. In fact yields of many crops have risen sharply". Rice and maize yields have tripled in eastern Burkina Faso, while the levels of soil nutrients remain what they were when French scientists first studied the area in the 1960s.
Even more remarkably, farming techniques are not vastly different. "All they do is apply some of their soil and water conservation practices more intensively," says Niemeijer's co-worker, social scientist Valentina Mazzucato. They erect stone and earth walls to keep the soil from washing off the land in the occasional heavy downpours. They spend more time weeding and thinning crops. They swap seeds and farm equipment and even land. And they work the land more intensively by forming labor gangs that tend each others' fields during busy times.
Back in the early 1970s, at the height of the Sahel droughts, Burkina Faso was widely seen as being on a one-way trip to desertification. Yet per-capita food production here is 20 percent up on 1970 figures. "Of course, life remains hard, but things are not going down the drain," says Niemeijer.
The same story comes from neighboring Niger, where 20 years ago the southern provinces were facing repeated droughts and fears of desertification. But again farmers seem to have turned things around. According to Boubacar Yamba of the University of Abdou Moumouni in the capital Niamey, rains remain 30 percent down on the figure in the 1960s and the population has doubled in 25 years. But millet farmers have diversified into growing vegetables and tree crops and tending livestock.
Similarly, in the highlands of western Kenya, where 1 000 people and more occupy each square kilometer, farmers are keeping ahead by replacing their maize monocultures with a much richer mix of crops. They produce milk and honey, and grow medicinal plants, trees for timber and fruit, and even weeds. Napier grass, once regarded as a roadside weed, is now widely grown for sale as feed for dairy cattle.
These stories are hard to reconcile with the statements of many United Nations agencies about advancing deserts. The Food and Agriculture Organization, for instance, says that "an area [of Africa] the size of Somalia has become desert over the past 50 years. The same fate now threatens more than one-third of the African continent... The main cause is mismanagement of the land." The Convention to Combat Desertification, completed in 1996, was designed to try and halt this trend.
But increasingly analysts are calling into question the whole desertification hypothesis. They say farmers are in many places responding positively to the challenges of rising populations and faltering rainfall. Even Camilla Toulmin, head of the drylands program at the London-based International Institute for Environment and Development and a key figure in drafting the Desertification Convention, now admits that "evidence for soil fertility decline [in Africa] stems from a few highly influential studies, which have been quoted again and again. Detailed field-level studies demonstrate that the soil fertility problem is far more complex."
The reality of life in arid Africa appears to be far more diverse than many believed. Yes, deserts do advance; but they also retreat. Soils do deteriorate and farms do get things wrong. But they can also get things right and make improvements in the most unlikely circumstances. Above all, says Singh, there is nothing inevitable about the link between population growth and spreading deserts. "There is no reason why Africa cannot feed itself."