Comparison of natural regeneration and radial growth variations of trees in the utilized and unutilized beech stands, Case study: Asalem forest

This study was carried out in the oriental beech communities in order to investigate the natural regeneration and assessment of radial growth trend from 1960 to 2016. In each area, 50 1000-m2 circular plots were established based on a random-systematic method. Regeneration was sampled on two concentric circles with an area of 20 and 10 m2 of the sample plot center (for seedling and sapling, respectively). Then, 160 core samples were taken from selective trees by increment. The results of harvested stand indicated that natural and human disturbances regimes lead to change in the diameter distribution, age distribution, radial growth pattern and establishment of tree's regeneration. In the unharvestedarea, sapling of F.orientalis and seedling of Carpinus betulus and Acer velutinum had the highest density. Whereas, the seedlings of F.orientalis and C.betulus were dominate in the harvested stand. During the studied period, 324 tree species were established in the unharvested area and the highest frequency of tree recruitment was belonged to 1970-1980 decades. However, in the harvested stand, 262 tree species were established and the greatest frequency was recoreded from 1960 to 1970 years. The radial growth of trees in the harvested area showed the higher variations during the studied period and the highest frequency of release events was belonged to moderate releases. Therefore, this stand should be managed in order to return their historical composition and structure, maintaining natural regeneration and the optimal development of stand for future.