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چکیده
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The establishment and development of oak (Quercus spp.) seedlings are frequently impaired by siteheterogeneity resulting from historical anthropogenic disturbances in Mediterranean basin woodlands.In particular, the alteration of forest structure and soil biotic and abiotic components can compromisethe natural regeneration of Persian oak (Quercus brantii Lindl.) in western Iran. This study aimed toinvestigate how soil properties, soil mesofauna diversity and stand structural indices differ between welland poorly regenerated areas. We sampled 105 plots in an oak woodland subjected to past disturbancesbut protected from human activities for the last 20 years. These 100-m2plots were distributed into twogroups: i) poorly regenerated plots (PRP) with only 0 or 1 newly established oak seedling, and ii) wellregenerated plots (WRP) with ≥3 seedlings. In each plot, we characterized the forest structure using threestructural indices, and determined the soil properties and mesofauna diversity. Structural indices werehigher in WRP than in PRP for height (0.83 and 0.23), diameter differentiation (0.74 and 0.36) and speciesmixture (0.90 and 0.21). Also, richness and diversity of soil mesofauna were lower in PRP than in WRP.Acanonical correspondence analysis (CCA) ordination clearly separated WRP, which were characterizedby a clumped spatial distribution of mature oak trees on fertile soils, from PRP that exhibited a uniformspatial distribution of trees established on soils with a higher sand content (63 and 59%) and a higher bulkdensity (1.7 and 1.3).The uniform spatial distribution of trees, which was less favourable to oak seedlingestablishment, was inherited from intensive past human disturbances. To favour oak regeneration, werecommend applying management actions in cooperation with land-users, in particular the conservationof small patches of tree clumps to act as islands of fertility and seed sources.
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