2012 BOIS ET FORETS DES TROPIQUES 2012 null(卷), 312(期), (8-20页)
REGENERATION DYNAMICS IN ACACIA TORTILIS SUBSP. RADDIANA IN TUNISIA'S BOU HEDMA NATIONAL PARK This study was conducted in Bou Hedma national park, which is in Tunisia's arid zone and was listed as a Unesco Biosphere Reserve in 1977. The park harbours Tunisia's only tree steppe region with Acacia tortilis (Forsk.) Hayne subsp raddiana (Savi) Brenan. Our approach involves a combination of satellite imagery, vegetation surveys and observations of the dendrometric characteristics of this Acacia species. Our interpretation of the satellite images shows that Acacia tortilis occupies a very large area (12 % of the park's total area) and is essentially located in zones with characteristically skeletal soils, as in grazing prohibition zones or detritic-colluvial deposits. The species also prefers zones more than 200 m above sea level, with deep soils and shallow slopes. Overall, observed Acacia tortilis cover is mostly less than 10%, with a very significant presence of young naturally regenerating seedlings more than 10cm in diameter.