ارزیابی و شناخت وضعیت زادآوری دانه زاد زالزالک، آلبالو وحشی و ارژن در جنگل های زاگرس مرکزی (مطالعه موردی: جنگل های دالاب استان ایلام)

Crataegus pontica, Cerasus microcarpa and Amigdalus orientalis are from important accompanying woody plant species in Zagros forests and their regeneration dynamic helps to improve the regeneration of tree species. This research was carried out with the aim of investigating and recognizing the regeneration establishment pattern of C. pontica, C. microcarpa and A. orientalis in three forest sites in Dalab­, Ilam province with different site conditions and also studing the their seasonal changes during spring and summer 2016. In each site one basic transect was established perpendicular to the slope and regeneration establishment positions including "under tree canopy", "under shrubs", "under bushes", "next to rocks" and "without vegetation space" with three replications were selected. For each replicate a 15m2 circular permanent plot to investigate the seasonal changes was established and the number and height of seedlings for each species was measured. The results showed that the seasonal changes of C. microcarpa regeneration are associated with a significant decrease. The most density of C. microcarpa seedlings was in south aspect and altitude class of below 1500 m a.s.l., and for A. orientalis was in north aspect and altitude class of above 1500 m a s l. The most density of C. microcarpa seedlings was found under the crown of oak trees, and for C. pontica was under the crown of shrubs and for A. orientalisat was next to the rocks. The most density of seedlings for C. microcarpa, C.pontica and A. orientalis was found in north side of tree crowns and also at the first third of tree crown radius. The most percentage of tall seedlings for C. microcarpa was at a first third of tree crown radius and for C. pontica and A. orientalis was at the third of tree crown radius. It was concluded that the crown of trees and shrubs has the most important role in seedlings establishment and protecting them against cold and heat. However, the role of rocks in soil preserving and seedlings establishment is considerable.