African ‘wall of trees’ gets underway

Three years after it was first proposed, preparations for an African 'wall of trees' to slow down the southwards spread of the Sahara desert are finally getting underway. The 'Great Green Wall' will involve several stretches of trees from Mauritania in the west to Djibouti in the east, to protect the semi-arid savannah region of the Sahel — and its agricultural land — from desertification.