Natural regeneration of Pinus brutia Ten. in a recreational public forest in Zawita-Kurdistan region, Iraq

Abstract

Zawita natural forest has recently has been subject to mass recreational activities during spring that have denuded large areas of the forest. It was thus essential to assess regeneration before designing optimizing strategies. To this end, we studied the overstory canopy and microhabitat conditions for recruitment of Pinus brutia Ten in 10 plots (20 × 25 m) on the southern aspects where the Zawita natural forest is still present. In total, 1540 regenerating P. brutia were recorded, 854 seedlings, 597 saplings, and 89 trees. Seedlings and saplings were more frequent beyond the canopy than under the canopy of the parent trees. Regeneration requirements differed between seedlings and saplings. The probability of the occurrence of seedlings was negatively correlated with increasing litter depth and increasing soil compaction. The density of saplings only showed a positive significant correlation with increasing slope. The nearest neighbor index showed a trend toward a positive spatial association between understory shrubs with their neighboring seedlings at a mean distance of 1.6 m. Overall, the study highlighted the requirements for seedling regeneration as a relatively open canopy cover, a light understory litter layer, and non-compacted soils. These results are a step towards designing effective management and restoration programs.

Keywords

Forest structure / Litter depth / Regeneration niche / Spatial pattern / Soil compaction

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