Clearing of land for agricultural use and cutting of timber over the centuries have severely reduced the once bountiful forest wealth. Forest fires have also taken their toll. In the higher and wetter portions of the Tell Atlas, cork oak and Aleppo pine grow in thick soils. At lower levels on thinner soils, drought-resistant shrubs predominate. The grapevine is indigenous to the coastal lowlands, and grasses and scrub cover the High Plateaus. On the Saharan Atlas, little survives of the once extensive forests of Atlas cedar that have been exploited for fuel and timber since antiquity.
The forest reserves in Algeria were severely reduced during the colonial period. In 1967 it was calculated that the country’s forested area extended over no more than 24,000 square kilometres of terrain, of which 18,000 km² were overgrown with brushwood and scrub. By contrast, woodlands in 1830 had covered 50,000 km². In the mid-1970s, however, the government embarked on a vast reforestation program to help control erosion, which was estimated to affect 100,000 cubic meters of arable land annually. Among projects was one to create a barrage vert (green barrier) more or less following the ridge line of the Saharan Atlas and extending from Morocco to the Tunisian frontier in a zone 1,500 kilometers long and up to twenty kilometers wide.
The barrage vert consists principally of Aleppo pine, a species that can thrive in areas of scanty rainfall. It is designed to restore a damaged ecological balance and to halt the northern encroachment of the Sahara. By the early 1980s, the desert had already penetrated the hilly gap between the Saharan Atlas and the Aurès Mountains as far as the town of Bou Saâda, a point well within the High Plateaus region. The barrage vert project was ended in the late 1980s because of lack of funds.
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