The planting of a 4,000 mile ‘wall’ of trees and shrubs across Africa has begun in an ambitious effort to halt the southward spread of the Sahara desert and stop vulnerable sub-Saharan habitats from drying up
Called the Great Green Wall, it will be nine miles wide and will traverse 11 countries in the Sahel zone of sub-Saharan Africa, from Senegal in the west and across the continent to Djibouti in the east. Planting started in Senegal in July. The wall is planned to be almost continuous, with breaks only for obstacles such as streams and mountains.
Other than stopping erosion and desertification, which now affects 40% of Africa, the vegetation will help to retain moisture for water sources such as Lake Chad, which has been slowly drying up during the past few decades. Organisers also hope it will create a valuable habitat for wildlife, help research into drought tolerant plant species and provide local people with food and fuel.
The United Nations Convention to Combat Desertification (UNCCD) believes the wall will also be a symbolic achievement for co-operation and stability in Africa.
The project was first proposed in the 1980s by Thomas Sankara, then head of state in Burkina Faso, before being put forward again in 2005 when it was presented to the African Union. Since then, the project has gained international support outside Africa.
The Global Environment Facility, which provides grants to developing countries for projects related to biodiversity, climate change, international waters and land degradation, has invested $108m (£68.9m) to support the project. Other international development institutions have so far given a total of $3bn (£1.9bn), including $1.8bn (£1.1bn) from the World Bank.