بررسي رابطه زادآوري درخت راش با شكل زمين

Relationship between regeneration of oriental beech (Fagus orientalis Lipsky) and land form.

This paper investigates the relationship between land form and location and natural regeneration of beech species. For this purpose, the beech communities over 100 m. above sea level at Namkhaneh district of Educational and Experimental Forest of Tehran University in Caspian region were selected. Based on renegeration condition and distribution at different land forms, data sampling was performed at four different land forms, including slope, valley, ridge and doulin, using 15 sampling strips with equal widths (2m), but different lengths, depends on different environmental circumstances. The strips were selected at 150 m. intervals. Where the longest and the shortest ones were 517 and 40 m., respectively. The doulin land from was selected where the regeneration cover was more than 30%. The doulin forms were divided into four aspects, including north, east, south and west faced directions for precise study of regeneration. Quantitative and qalitative characteristics of natural regeneration of beech (Fagus orientalis Lipsky) were recorded and canopy cover of the beech old-growth stands was estimated. The results showed that there were significant differences between the four landforms in respect to regeneration cover of beech species, where the ridges had the greatest values. The greatest frequency of beech seedlings on ridge and valley and as well as slope and doulin land forms were found at <30 and 30-130 cm height classes, respectively. There was not significant correlation between beech regeneration frequency and different aspects within the doulin land form. Therefore, the average density of the seedlings per m2 was 0.8 (equal to 8000/ha). 70% of the seedlings were healthy and the rest were not sound.