An ambitious plan to stop the southward advance of the Sahara Desert also aims halt the spread of Islamic terror.
Scientists are planting a wall of trees and shrubs 15km (nine miles) wide that will stretch 7,000km across the continent. When completed, it will be the largest horticultural feature in history.
The Great Green Wall project is designed to stop the degradation of the Sahel, the arid region just south of the desert proper which is the poorest area of the world’s poorest continent.
The southward extension of the Sahara is causing poverty which is believed to feed militant Islamist groups such as Boko Haram in Nigeria, which kidnapped more than 200 schoolgirls in April. Insurgencies have also been active in Algeria and Chad.
The British House of Commons foreign affairs committee warned in March of "A new frontline of violent extremism" saying that, unless it was checked, troubles in the Sahel could have effects “felt more widely across the world”.
The region’s population is set to triple to more than 300 million by 2050, putting additional pressure on food and water while the productive capacity of the land is declining.
“The
effects of desertification are increasingly felt globally as victims turn into refugees” or “turn to radicalisation, extremism or resource-driven wars for survival,” warned the UN.
Lake Chad, which supports 30 million people in four countries, has shrunk to a fifth of its size 50 years ago.
“Most of the guys who are into terrorism in that region used to be farmers, fishermen and herders who depended on the lakes,” said Uche Okpara, an expert on agricultural economics from Leeds University.
The Great Green Wall project, conceived by British explorer Richard St Barbe Baker during a 40,000km expedition to the region in the 1950s, is being spearheaded by botanists and seedologists from the Royal Botanic Gardens, Kew, with the support of the World Bank, the African Union, the UN’s Food and Agriculture Organisation and national governments.
Eleven countries, Burkina Faso, Djibouti, Eritrea, Ethiopia, Mali, Mauritania, Niger, Nigeria, Senegal, Sudan and Chad, have created the Panafrican Agency of the Great Green Wall.
Proposed route for the Great Green Wall
Kew has been at the forefront of efforts to preserve the planets genetic diversity, having collected and stored seeds from some 10 per cent of the world’s vegetation. It hopes to have a quarter of global fauna represented in its Millennium Seed Bank by the end of this decade.
“Not every species will grow in the Sahel,” said Moctar Sacande, a Kew seedologist from Burkina Faso who is leading a team. “The main challenge is getting the villagers to maintain their involvement. We’re trying to show them that they don’t need to wait four or five years to see the benefit.”
The Kew team hopes to have planted two million seedlings on 4,000 acres near 120 villages by next year. The plants are are hardy, but sometimes need special treatment.
Some, for example, require smoke solutions or sulphuric acid to trigger germination. To encourage villages to co-operate, Sacande has mixed the wall with fast-growing grasses for grazing livestock.
Longer-term benefits include plants that produce gum arabic (used in chewing gum and colas) and fruits that can be eaten in jams or used to make local sauces.
