More from Senegal

5 Apr

Can Re-forestation Counter the Effects of Global Warming in the Sahel?

Payene, Senegal: As Babakar Mbaye strides assuredly across the sandy, arid terrain beneath a glaring sun, he rhymes off the names of each small plot into which his modest farm is divided. “This piece is Dakar Dhiatiri,” he explains, “and here I planted millet. That piece over there, we call Dakar Mamelles, where I planted two rows of millet beside every row of cowpeas. Every plot has a name that sometimes only we use, while other people in the village may have another name for it.”

Each parcel of the farm’s 11 hectares is encircled and dotted with trees.  Most of them were planted by Mbaye’s father, Thierno, in an attempt to stem soil erosion and stop the slow, insidious desertification of the land from which this family earns its livelihood. Yet in spite of years of tree planting, the crops here are far from abundant. The problem, says Mbaye, is not only a lack of precipitation, but changes in the way it comes. “We used to get the first rainfall in May,” he said, “with more steady rains coming a few weeks later. But last year, it took much longer for the big rainfall to come and most of my crop dried up. I let a neighbour bring his sheep here to eat the dying seedlings.”

A member of the Union of Peasant Groups of Mekhne, or UPGM, Mbaye has been working hard to bring development to Payene, home to 150 families. But as scientists debate the features of a planet that is heating up and getting drier because of global warming, Mbaye, 30, wonders if all his efforts at reforestation and crop management will prove no match for its effects in his tiny piece of West Africa’s semi-arid Sahel region. What’s more, some question whether the decrease in rainfall in an area so close to the Sahara Desert is simply a natural phenomenon.

Peasant farmers in central Senegal have been dealing with drought for more than two decades now, said Ndiakate Fall, secretary of UPGM. It was one of the reasons why some of them joined together in 1985 in an effort to find a solution for their problems. “The land had become degraded after years of planting peanuts,” he said, “and above all from the drying out of the environment.”

A group of educated farmers sons, the first members of the UPGM began to speak to their elders, said Fall, in a search for solutions that might bring their farms back to life. They began a campaign that eventually saw tens of thousands of trees, including baobabs, acacia, and fruit trees, planted around small plots. Any farmer joining the union, which has grown from five villages to 82 and has some 5000 members, is obliged to plant trees. They also went back to growing typical food crops such as millet and cowpeas, and using organic fertilizers instead of chemical ones.

However, said Gerrit Hoogenboom, a crop scientist at the University of Georgia who is familiar with the region “questions about the rains have always been there. If you talk to people, they have a lot of indigenous knowledge; they look at trees, they look at birds and whatever else is out there to see what type of rainy season they’re going to get.”

In fact, rainfall in the Sahel began decreasing in the 1950s, says a study carried out under the auspices of the United Nations’ Inter-governmental Panel on Climate Change. It continued until the late 1980s, after which a slow recovery began although not to levels typical of the first half of the century. Some scientists have ascribed the decrease to overgrazing and the conversion of woodland to agriculture, increasing surface albedo – the ratio of incoming sunlight to what is reflected back by a natural surface – and reducing the moisture supply to the atmosphere.

Another possible culprit, is the warming of the Indian Ocean and parts of the tropical Atlantic, attributed in one model at least to man-made causes, a combination of anthropogenic greenhouse gases and sulphate aerosol. “But this is not seen in all models,” said John Fyfe, of the Canadian Center for Climate Modelling and Analysis in Victoria, B.C., “and remains a matter of debate. The predicted pattern of change overall is for 21st-century drying in North and South Africa, and moistening in central Africa.” 

According to Joel B. Smith of Boulder, Colorado-based Stratus Consulting, an environmental research firm, while rainfall patterns are still being studied, there is no doubt that temperatures will go up, although by how much is still a big question. “And one of the issues there,” he said, “is that because the temperatures are already so high, the evapo-transpiration goes up exponentially. In the tropics, particularly the arid tropics like the Sahel, it would take an awful lot of precipitation increase to offset it. I think most of the models don’t show that.”

Rising temperatures also mean fewer options for planting. “Millet is the crop that requires the least amount of water and withstands the highest temperatures,” said Hoogenboom. “But you can only push those temperatures up to a point.”

Indeed, the IPCC estimates that, overall, the African continent could lose as much as 600,000 square kilometers of cultivatable land to climate change. With 70 per cent of African peasant farmers dependent on rain-fed, small-scale agriculture, just like the Mbaye family, aid experts say that poverty alleviation policies needs a complete rethink.

Although his extended family of 12 survives on an average monthly income of about $96, Mbaye remains convinced that participation in the UGPM is improving their lives. The Union has worked with international partners, such as New York-based The Hunger Project, which brought two new wells into Payene, allowing villagers to plant a co-operative garden.  Other campaigns have resulted in micro-credit schemes, free seeds from the government and community solar panels for electricity. For these at least the intense, steady sunshine will give them something to harvest.

And while many rural poor in Africa must migrate to cities or even other countries to stave off total ruin, Mbaye has no wish to leave. “My name in Wolof actually means farmer,” he said, “and I like what I do very much. I can work out here all day and not get tired.” 

While his future remained uncertain, Smith believed that planting trees “can help. Trees create shade, which can keep the temperature down somewhat. But whether it’s enough, depends on the effects of climate change.”






Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: