Ukrainian Journal of Forest and Wood Science

Dynamics of natural regeneration in an endemic and protected Portuguese oak forest in Western Algeria

Sid Ahmed Aouadj*, Mohamed Zouidi , Hadj Habib Houari, Belgacem Nouar, Hadjer Bekhedda

sidahmed.aouadj@univ-relizane.dz

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Abstract

Despite the ecological and silvicultural importance of Portuguese oak (Quercus faginea Lam.) in North Africa, its population dynamics under increasing anthropogenic pressure remain poorly documented, limiting evidence-based conservation planning. The aim of this study was to assess the current status of the Portuguese oak ecosystem and examine the effects of human proximity and diameter structure on natural regeneration, as well as to characterise the physicochemical properties of soils at the investigated sites. The study used stratified random sampling based on 100 circular plots of 400 m² distributed according to predefined distance classes. Results indicated that the distance from the nearest agglomerations significantly affected stand density across all diameter classes. The coefficients of determination ranged from 0.75 to 0.91, indicating that distance from human agglomerations explained a substantial proportion of the variation in the density of different diameter classes. Stand density increased with distance from human settlements, while seedlings and mature seed-bearing trees predominated and the intermediate diameter classes remained poorly represented. Natural regeneration through seedlings was also found to be associated with diameter structure: seedling density increased with the density of trees in the other diameter classes, with R² values ranging from 0.54 to 0.68. Soil pH ranged from 5.0 to 6.3 and generally decreased with depth. The surface horizons contained higher levels of organic matter, carbon and nitrogen, whereas clay accumulation in the deeper horizons was particularly evident at the Djefal and Aïn El Hadjer sites. These findings highlighted the vulnerability of the Portuguese oak ecosystem to anthropogenic pressure and suggest the need for appropriate conservation and restoration measures, particularly the protection of natural regeneration and the reduction of grazing pressure near human settlements. This study could serve as a baseline for monitoring vegetation dynamics and changes and for planning the conservation and restoration of Portuguese oak stands

Keywords

diameter classes; distance; seedling density; human proximity; anthropogenic pressure

Suggested citation
Aouadj, S.A., Zouidi , M., Houari, H.H. , Nouar, B., & Bekhedda, H. (2026). Dynamics of natural regeneration in an endemic and protected Portuguese oak forest in Western Algeria. Ukrainian Journal of Forest and Wood Science, 17(2), 39-57. https://doi.org/doi: 10.31548/forest/2.2026.39
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