The Green Dam in Algeria: From an Ambitious Project in 1971 to an Environmental Rehabilitation Strategy in 2023, Djelfa Province as a Model

Abstract

The Algerian government has launched a project to rehabilitate the Green Dam, which was established in 1971 to protect ecosystems and combat desertification. It extends over 1500 kilometers (from east to west) and 20 kilometers (from north to south) across 13 provinces. With the aim of economically exploiting, it through the cultivation of fruit trees, enhancing agriculture and livestock, and improving infrastructure. The research paper aims to track the course of this great project since 1985 and monitor its developments every 10 years, including the government's new decision to rehabilitate the Green Wall in 2023. We used both old and new remote sensing data. Two sources of satellite images were used: (1) GLC_FCS30D, the Global Land Cover product for the years 1985, 1995, 2005, and 2015, and (2) satellite imagery for the year 2025 from the Sentinel-2 multispectral satellite. The NGCC GLC_FCS30D database (Global Land Cover Maps) was produced with a resolution of 30 meters derived from temporal Landsat images and advanced classification methods. Given the diversity of land cover types displayed, especially forests, the dynamics of vegetation can be measured over the long term. GLC_FCS30D mapping data was processed to extract and measure the amounts of forested areas for 24 municipalities across the study area. After an extensive study over the monitored periods, we reached a series of results, particularly characterized by forest instability, fragility of the forest cover, and forest degradation. This is due to several factors, including climate change and human activities such as illegal logging.