اثرات بلندمدت آتش‌سوزی بر ترکیب گونه‌های چوبی و تجدید حیات طبیعی آنها در جنگل‌های هیرکانی (مطالعه موردی: جنگل لساکوتی تنکابن، استان مازندران)

     This current research was investigated the long – term effects of fire on vegetation and regeneration of beech (Fagus orientalis L.) in the mountain forest in Lesakoti forests in Tonekabon city in north of Iran. In both of burnt and unburnt areas, 30 plots 1000m2 and in total 60 sampling plots were identified using random-systematic 100 m × 150 m grid and density and DBH of trees and density of shrub and regeneration were recorded. Results indicated that the fire has changed the forest uneven aged structure to irregular even aged structure in burned area, and by destroying of low diameter trees and establishment of more light demanding species instead of shade tolerant species, changed primary situation of the burned area. The fire has changed forest tree composition from pure stands to mixed stands as the species of Carpinus betulus, Carpinus orientalis, Acer velutinum, Acer platanoides, Acer cappadocicum, Acer campester, Cerasus avium, Fraxhnus excelsior and Quercus macranthera were appeared. The result showed that fire decreased tree density in the burned area (130.02 in burned area and 236.71 in unburned area). There was significant difference as total density of regeneration between burned and unburned areas (1765 in burned area and 1283 in unburned area), and for each species regeneration there was significant difference. There was significant difference in density of shrubs between two areas, so that density of shrubs in burned area (250.02) was more than unburned area (193.77). According to the conditions of the study area, the implementation of silvicultural operations can improve the regeneration composition and density condition.