Structural Dynamics of Atlas Cedar in the Tala Guilef Forest: A Favorable Situation that can be Improved by Controlling Anthropogenic Pressure

Abstract

Understanding stand structure and regeneration dynamics is essential for assessing the functioning, resilience, and conservation status of Mediterranean forest ecosystems. Atlas cedar (Cedrus atlantica), a keystone species of high conservation concern, has experienced significant decline across its natural range. This study examines the structural dynamics and regeneration patterns of C. atlantica in the Tala Guilef forest (northwestern Djurdjura, Algeria) under varying local ecological conditions and disturbance regimes. Field data were collected from 32 square stands (625 m² each), representing a range of elevations, slopes, exposures, vegetation cover classes, and stand compositions. Structural attributes were assessed using dendrometric measurements (diameter at breast height, total height, crown dimensions, basal area, and density), while regeneration was evaluated across four developmental stages. Cone production was quantified as an indicator of reproductive potential, and disturbance factors were recorded through direct field observations. The results indicate that C. atlantica dominates all stands and is associated with low to moderate woody species diversity. Regeneration was present across all sites, although its density varied significantly with ecological conditions. Seedlings were more abundant on north-facing slopes, whereas advanced regeneration stages were more frequent on south-facing slopes. Regeneration density peaked at higher elevations and under intermediate vegetation cover (25–50%). Cone production was widespread and did not limit regeneration. Diameter distributions consistently exhibited an inverted J-shaped structure, indicating continuous recruitment. Structural attributes such as diameter, height, and basal area were generally higher in mixed stands and at medium elevations. Grazing was identified as the dominant disturbance factor, affecting more than 80% of the surveyed stands and likely constraining regeneration success. Despite these pressures, the overall structural patterns suggest that C. atlantica populations in Tala Guilef maintain active dynamics and regeneration capacity. Reducing anthropogenic pressure, particularly grazing, and prioritizing the protection of stands with high regeneration potential may enhance natural regeneration processes and support sustainable forest management.