In 1971, Algeria began planting a 1,500-kilometre, 20-kilometre-wide “Green Dam” to help combat desertification across its semi-arid high plateaus

In the early 1970s, Algeria launched a forestry experiment on an unusually large scale. Across Algeria’s semi-arid high plateaus, authorities began establishing what became known as the Green Dam, a vast belt of trees and vegetation designed to slow desertification and protect land between the Mediterranean north and the Sahara to the south.

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