Abstract In semi-arid environments like Zagros (western Iran), soil properties are influenced by vegetation cover particularly tree species. This research addressed the effect of three oak (Quercus brantii Lindl.) growth types (seed-origin trees, old and young coppice forms areas) on soil physio-chemical and biological properties along an elevation gradient. Soil sampling was carried out at two soil depths (0-5 and 5-25cm) and three elevations (low, middle and high) in the three types of growth and in treeless area. We found lower values in soil nutrients, carbon sequestration, soil moisture and microbial activities in the open area than beneath the vegetation cover at all elevations. There was a significant influence of the type of growth: values of most of the biological and chemical properties were lower in the young coppice type than in the old coppice type and seed-origin trees. We also found negative correlations between carbon sequestration and microbial biomass nitrogen and basal respiration in all types of growth. These results thus emphasize the role of patches of woody vegetation in creating ‘islands fertility’. The type of growth significantly influence soil properties through the whole elevation gradient and the old seed-origin type was the most favourable for soil fertility.
