بررسي ساختار جنگل هاي كمتر تخريب يافته بلوط در استان ايلام

Structure Of Less Degraded Oak Forests in Illam Province(Southwest Iran)

Structure study of natural and less degraded Zagross forests (second important natural forest ecosystem in Iran) while considering degradation proccess in them and exigency of their regeneration is very necessary. In this study, 12 regions of less degraded oak and wild pistachio forests in Ilam province, in several different elevations and conditions were selected . Information items about regional factors as well as forest stand structure such as: dbh, canopy diameter, height were gathered and analysed by use of suitable softwares of STATISTICAL and EXCEL. In order to describe the stand structures, tables and graphs releted to canopy, dbh, canopy diameter and height distributions, regeneration, necromass were used and are presented.. Results show that, the stands are basically uneven-aged old forests among which Quercus persica with its vigorus existence outcrops as pure or original species of forest type. Other results show that, maximum forest canopy, maximum basal area, and maximum volume per hectare are 35% , 22.6m2 and 46.3m3, respectively. Some of the DBH distribution graphs in the stands indicate an uneven, aged stand, but most of them are old stands of very little regeneration . Results also show that number of dead trees and amount of dry branches in canopy are very good indices for determination of degradation in forests.