Algeria's Barrage Vert (Green Dam) — State Afforestation Belt Across the High Plateaus

The Barrage Vert (Green Dam) was conceived under President Houari Boumediene and launched around 1970-71, formalised by 1974, as a state afforestation belt intended to run roughly 1,000-1,500 km along Algeria's High Plateaus and steppe zone, about 20 km wide, to hold back desertification from the south. It was carried out by the Direction Generale des Forets (DGF) via military conscripts and later the Office National des Travaux Forestiers, and Algeria folded it into the African Union's Great Green Wall for the Sahara and Sahel Initiative after 2007.

The original programme planted Aleppo pine (Pinus halepensis) at high density on the High Plateaus. A 2023-2030 relaunch framework took effect on 29 October 2023, coordinated under Decree 24-376 (18 November 2024), pivoting away from the original monoculture approach toward agroforestry with native and diverse species (Atlas pistachio, holm oak, acacia, carob, argan, olive, almond) and greater involvement of local pastoralist populations in planning and maintenance.

Reported results diverge sharply by source: an FAO technical note cites about 100,000 ha reforested with a claimed 75% survival rate after ten years, while an independent academic review ('Bilan critique du barrage vert en Algerie') finds only 120,000 of 160,000 ha planned were realised, with roughly 42% survival, failure rates above 40%, and about 20% further loss to pine processionary moth infestation. A peer-reviewed remote-sensing study of the Moudjbara perimeter in Djelfa Province found open-plantation canopy growing from 0 ha in 1972 to 11,074 ha by 2009, then collapsing 43% to 6,303 ha by 2019. As of December 2025, Algeria's DGF reports roughly 26,000 ha reforested since the October 2023 relaunch, against a national forest patrimony of about 4.1 million hectares (some 2% of national land area).

The programme's documented weaknesses are extensive: excessive planting density (over 1,600 stems/ha) on shallow, encrusted soils poorly suited to Aleppo pine; heavy losses to overgrazing, illegal cutting and pest infestation; and FAO describes natural regeneration in stands over 60 years old as 'practically null'. Minimal local and pastoralist involvement in the early decades undermined long-term maintenance — a gap the 2020s relaunch is attempting to correct. Reported survival/canopy figures also diverge sharply between sources, illustrating a persistent reporting-consistency problem.