Phytoecology of Pinus Halepensis Mill. stands in the Semi-Arid Region of Saida (Western Algeria)

Abstract

We conducted 166 floristic surveys in four Aleppo pine (Pinus halepensis Mill.) stands in the semi-arid region of Saïda, western Algeria, to investigate the relationships between plant community composition and selected climatic and edaphic variables. The study area is characterized by a cool-winter, semi-arid climate, with mean annual precipitation ranging from 300 to 400 mm. The soils beneath the surveyed stands contained 0.40–2.99% organic matter and had pH values ranging from 6.2 to 8.1, indicating slightly acidic to moderately alkaline conditions. Electrical conductivity ranged from 0.10 to 0.98 mS cm⁻¹, and the sampled soils were predominantly non-saline and calcareous, with CaCO₃ contents reaching up to 30.95%.
A total of 228 plant species belonging to 158 genera and 46 families were recorded. The most species-rich families were Asteraceae (49 species; 21.5%), Fabaceae (21; 9.2%), Poaceae (14; 6.1%), Lamiaceae (14; 6.1%), and Brassicaceae (13; 5.7%). The biological spectrum followed the order TH > HE > CH > PH > GE. Therophytes were the dominant life form (44%), followed by hemicryptophytes (21%), chamaephytes (20%), phanerophytes (8%), and geophytes (6%). The predominance of therophytes is consistent with arid conditions and disturbance; however, the respective contributions of climatic conditions and human activities were not quantified in this study. These stands warrant targeted protection and monitoring to support natural regeneration and reduce avoidable anthropogenic pressures.