Aug 31st 2016, 23:00 BY J.A.R.B.
BUILDING a wall of trees across the width of Africa is a tall order. Solving the twin problems of land degradation and desertification poses a greater challenge still. But more than 60 years after it was first proposed, just such a project is underway at the edge of the Sahara. The opening ceremony of the Olympics in Rio de Janeiro thrust it into the limelight, with footage of its progress. On completion, it is set to be the world’s largest living structure, three times the size of the Great Barrier Reef. What is Africa’s “Great Green Wall”?
In 1952 Richard St Barbe Baker, a British environmental scientist, proposed planting a swathe of trees across the southern reaches of the Sahara. The trees would block the wind and sand that move southward from the desert and improve the quality of the soil by binding sediment together and adding nutrients to the mix. Although Mr Baker was unable to convince others of his plan during his lifetime, the idea has since taken root. In 2005, Olusegun Obasanjo, then president of Nigeria, revisited Mr Baker’s proposition, seeing in it an answer to some of the social, economic and environmental problems afflicting the Sahel-Sahara region. An estimated 83% of rural sub-Saharan Africans are dependent on the region’s land for their livelihoods, but 40% of it is degraded—worn away by soil erosion, human activity and scorching temperatures—leaving much of it unfit for use.
In 2007, Mr Obasanjo gained the support of the African Union. The Great Green Wall Initiative was launched the same year. Today some 21 African countries are involved in the project, which has grown in scope. Trees have been planted, but building a wall of them is no longer the priority. Instead, the wall of trees has become a vehicle for a wider goal: countries in the region working together to tackle climate change, food security and economic growth. Recent projects include abating soil erosion and improving water management in Nigeria, agri-business development in Senegal and forestry management in Mali. Each country takes it own approach to achieving shared goals. Some focus on community planning through education, while others are expanding investment in technology and training for farmers. Since the project started, 15m hectares of land have been restored in Ethiopia and 20,000 jobs have been created in Nigeria.
In May the Great Green Wall Initiative held its first conference, in Dakar. African leaders renewed their commitment to the project and pledged to accelerate its progress with the “Dakar Declaration”. They will show off their achievements at COP22, a global climate-change conference, in Morocco later this year. Plans are afoot to take the idea to other continents too. As Chinese emperors knew all too well, a great wall takes time to build but can last forever. With luck, Africa’s green one will prove just as resilient.