Success story: Regreening Africa with forested farms

16 Dec 2009

The arid Sahel region that spans Africa, just south of the Sahara Desert, is the home to a surprising homespun success story.

As globetrotting journalist Mark Hertsgaard reports in The Nation:

a tree-based approach to farming … has transformed the western Sahel in recent years, … providing one of the most hopeful examples on earth of how even very poor people can adapt to the ravages of climate change.

Here’s how it works:

a technique local farmers had used for centuries, but he adapted it to the new climate conditions he faced. It had long been the practice among Sahelian farmers to dig zai—shallow pits—that concentrate scarce rainfall onto the roots of crops. Sawadogo increased the size of his zai to capture more rainfall. But his most important innovation, he says, was to add manure to the zai during the dry season, a practice his peers derided as wasteful.

Sawadogo’s experiments worked: by concentrating water and fertility in pits, he increased crop yields. But the most significant result was one he hadn’t anticipated: tiny trees began to sprout amid his rows of millet and sorghum, thanks to seeds contained in the manure. As one growing season followed another, it became apparent that the trees—now a few feet high—were further increasing crop yields while also restoring soil fertility.

This seems like it definitely could help people cope with climate change in the future. But the impression the article gives is that the problems they’re facing already are because of climate change, and that this technique could help them cope.

Hertsgaard doesn’t present any strong evidence that the climate in Mali and Niger (where he reports from) has changed significantly so far. It could have, but he doesn’t say so, and only cites one farmers’ perception, writing, “in his mind, the droughts of the 1980s marked the beginning of climate change.”

Later in the article, he describes how national policies hurt the landscape:

In Mali, tree management had been part of traditional agriculture…. But using trees was abandoned when cutting wood became a crime. First the French colonial government declared all trees to be state property, enabling government officials to sell timber rights to woodcutters. Similar arrangements continued after independence. Meanwhile, farmers caught pruning or cutting trees were punished. As a result they would uproot seedlings to avoid later hassles. Needless to say, several generations of this left the land denuded and increasingly desiccated.

It sounds to me like poor management, rather than climate change, is the culprit. And the greening of the area could actually be aided by climate change: that is, these people could be among the few winners who actually benefit from global warming (at least in the short run). That’s because the tropics are expanding—that is, growing larger, away from the equator. On either side, north and south of the wet tropics are the arid semitropics. Mali and Niger are in this transition zone. As the tropics expand, I’d expect that they would get wetter. I haven’t looked into this in detail yet, but if this is right, then it paints a much different picture than Hertsgaard’s story. Rather than an example of “how even very poor people can adapt to the ravages of climate change,” perhaps it is an example of how people can overcome disastrous management, high population pressure, and other impacts on the landscape.

It might seem like hair-splitting to dwell on this issue of whether the changes are due to climate change or poor management. But a lot may be riding on the distinction. Poor countries are trying to squeeze money out of rich countries, as reparations for all the climate-warming CO2 they’ve spewed. (See, for example, “Cash for Thunder: Bolivia Demands ‘Climate Reparations'”.)

If the changes are wrought by rich countries greenhouse gases, countries like Bolivia, Mali, and Niger might get some cash to help with agroforestry projects. If the changes are down to poor management, they’ll have to rely on traditional aid—or on their own efforts.

In any case, agroforesty seems like it could really help, regardless of how the western Sahel got to its current state. The success so far is mostly homegrown, with farmers innovating, seeing the success of this approach, and spreading the word about it, which makes it seem very sustainable, and like it could scale up to reach more people and more farms.

And crucially, this approach could help now, and help in the future whatever climate change may bring. Hertsgaard writes: “The point is that tree-based crop systems are a win-win: they help farmers adapt to climate change even as they boost food security and reduce rural poverty.”

As I wrote in a review of the book Understanding Climate Change Adaptation: Lessons from Community-based Approaches, aiming for this kind of resilience, which helps now and in the future, may be the best way to go to help communities cope with today’s climate variability and with coming climate change.

A recent New Scientist article on agroforestry has a bit more on how agroforestry is already helping. As Fred Pearce reports, “a new analysis (pdf) by the World Agroforestry Centre in Nairobi shows that often, the more intensive the farming the more trees that farmers plant—for fruit, medicines, fodder crops, windbreaks, and fuel.”

“Pioneer farmers remove trees from the landscape, but as intensive systems develop, there is an increase in planting useful trees,” says study leader Robert Zomer. Or, if it’s like the agroforesty in Mali and Niger, the farmers are simply encouraging trees that sprout on their own, rather than planting the trees.


books I've read on failure & grace

The World Without Us
The Last Oil Shock: A Survival Guide to the Imminent Extinction of Petroleum Man
A Paradise Built in Hell: The Extraordinary Communities That Arise in Disaster
Hell and High Water: Global Warming--the Solution and the Politics--and What We Should Do
The Worst Hard Time: The Untold Story of Those Who Survived the Great American Dust Bowl
The Tipping Point
Three Cups of Tea: One Man's Mission to Promote Peace... One School at a Time
The Upside of Down: Catastrophe, Creativity and the Renewal of Civilization
Out of Poverty: What Works When Traditional Approaches Fail
The Little Ice Age: How Climate Made History, 1300-1850
Confessions of an Eco-Sinner: Tracking Down the Sources of My Stuff
Deep Economy: The Wealth of Communities and the Durable Future
The Geography of Bliss: One Grump's Search for the Happiest Places in the World

Mason's favorite books »