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In fact the results have been wonderful. Better yet it is something that the people all believe in.
Even more noteworthy they can often simply fence in a block of land to allow natural vegetation to take off. With that base it is much easier to insert productive trees and to bring in cattle for mob grazing to start building soil carbon content.
This thinking will also encourage volunteerrism as well A farmer can grow shade trees to provide fertilizer. The knowledge is out there. A lot of it is easy as well..
A wall of trees is being built across Africa to hold back the deser
7 September 2020
https://www.newscientist.com/article/2253784-a-wall-of-trees-is-being-built-across-africa-to-hold-back-the-desert/
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A wall of trees could help prevent desertification in Africa
Great Green Wall
Its proponents say it will be a new world wonder. A plan for an 8000-kilometre-long, 15-kilometre-wide wall of trees stretching the width of Africa to hold back encroaching deserts and provide people with livelihoods has been embraced by 11 countries since its launch 13 years ago. Has it worked so far?
The first comprehensive status update on the Great Green Wall, released today, paints a mixed picture of efforts to reforest degraded land to a fertile state and provide livelihoods across the Sahel, the semi-arid region south of the Sahara desert in North Africa.
So far, 17.8 million hectares have been restored, 84 per cent of it in Ethiopia, according to the report for the United Nations Convention to Combat Desertification (UNCCD). The pace needs to increase dramatically: the goal is for the restoration of 100 million hectares by 2030.
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Despite this, Salima Mahamoudou at the World Resources Institute in Washington DC says that even having numbers is refreshing progress. “But is the number good enough? No, because we need 10 times more for the Sahel,” she says. Mahamoudou, originally from Niger, thinks the 2030 goal is a stretch but not impossible.
The project’s initial idea of a contiguous wall of just trees has shifted to a vision of a wider band of vegetation. That is a good thing as it reflects different local social and ecological factors along the wall’s path, says Deborah Goffner at the French National Centre for Scientific Research (CNRS). She supports the project, but is clear-eyed about its failings.
In Senegal, she says: “The ambition was gigantic, the financial means were peanuts.” Funding has been tricky in other countries too: today’s report warns it has been “insufficient, unpredictable and insecure”.
Another problem is that areas aren’t always greened in a way backed up by science. Goffner was dismayed to see Senegal planting just two or three tree species on huge plots of land. She contributed to two field trials there to see what species people wanted and to test whether they grew. In one area, it turned out that acacia trees had a survival rate of 20 per cent at best and it was better to just fence land off for vegetation to naturally grow back. In the other, 90 per cent of trees survived. “There’s no one size fits all,” says Goffner.
Commonly, exotic species such as eucalyptus were planted, which grow fast but won’t make land more productive, says Moctar Sacande at the UN Food and Agriculture Organization (FAO). “Very often, the wrong species have been planted,” he says. “There have been a lot of mistakes,” although he adds efforts are under way to rectify that.
There is also very little monitoring of how trees have fared after planting, says Mahamoudou. Today’s report notes that monitoring expertise has been “missing in general”. There are signs of promise: the FAO is tracking 50,000 hectares of trees by satellite, for example.
Has the wall stopped desertification? Not really, says Goffner. The UNCCD doesn’t have figures for abated desertification, but a spokesperson says “a regreening of some of the Sahel countries gives some hope that things are possible”.
In terms of helping people, today’s report says 335,000 jobs have been created, some in restoring land, others in selling products from trees, such as gum arabic. At its current scale, says Moctar Sacande at the Food and Agriculture Organization, the project won’t have stopped migration northwards to Europe, but reaching the 2030 target would.
The wall may have been imperfect in delivery and too small so far, but observers say that is no reason to give up. Mahamoudou thinks local entrepreneurs may see ways to profit from tree products or restoration, and massively help speed things up. Better funding will be key, she adds.
And as Goffner says: “It is easy to say maybe it’s not everything we would have hoped for in the first 10 years. But I think that’s normal. The idea of doing nothing is not possible.”
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