جستجوی مقالات مرتبط با کلیدواژه « Q. libani » در نشریات گروه « جنگلداری »

The aim of this study is to investigate the quantitative changes in the biometric indices of Lebanon oak (Quercus libani Oliv.) and gall oak (Q. infectoria Oliv.) during pollarding process. In a part of the two pollarded strands in northern Zagros of Iran, in which three years had passed from its last pollarding, the name of woody species was recorded and diameter (dbh), total and crown heights, and two perpendicular crown diameters were measured before and after pollarding in a full callipering assessment of all trees (dbh ≥ 5 cm). The results showed that in the pollarding process, crown height and crown area of oak trees decreased on average 15.73 and 30.06%, respectively. In both studied species, the reduction of crown area is significantly more than the crown height. In terms of reduction in crown height and crown area, there was no significant difference between Q. infectoria and Q. libani trees. The most decrease in crown height (27.99%) and crown area (44.85%) indices on diameter classes are related to Q. infectoria trees belonging to the 35 cm diameter class and Q. libani trees belonging to the 55 cm diameter class, respectively. The results indicate a higher decrease in the crown area compares to the crown height of oak trees due to pollarding practice; therefore, it is necessary to partially compensate for this decrease in the crown area by leaving some branches during each pollarding operation, because preserving the canopy is very important for Zagros-forest ecosystems. The only way to conserve these resources is to create a participatory approach as part of the transitional forest policy.

The oak leaf-roller moth (Tortrix viridana L.) damages the Zagros forests greatly by feeding upon leaves and sprouts of different species. The current study was carried out in 2015 in order to investigate the influence of cardinal directions on quantity features of oak tree and on the demographic changes of oak leaf-roller moth in Ghabr-e-Hosein area (Piranshahr) located in oak forests of west Azerbayjan. In every main geographical directions 30 gall oak trees (Quercus infectoria) and 30 Lebanon Oak trees (Q. libani) was measured using transect method and the pest larvae were counted from the branch tip inward and also quantity features of the host trees were recorded. Results showed that the maximum crown diameter was on the east while the minimum was on the south and north. The highest and lowest diameters at breast height (DBHs) were on the south and north, respectively. In addition, results showed significant differences (p

Conservation and development of Zagros oak forests requires collecting appropriate seeds for reforestation and afforestation plans. For this purpose, seeds of 60 trees of Quercus brantii, infectoria and libani (20 trees from each species) were collected from forests of Baneh, western Iran. After picking up 5 trees with distinct seed weight, the correlation between seed morphological characteristics and its growing traits like seed germination parameters and primary growth of seedling was investigated. The results showed that Quercus libani had larger seeds and seedlings compare to other species, but no significant differences in germination rate were observed between these three species. Also Quercus infectoria showed highest average time of germination. Regardless of species, primary growth of seedlings was affected by different seed morphological characteristics. So that, wider, more circular, bigger and heavier seeds produced larger seedlings. This correlation was higher in Quercus brantii and lower in Q. infectoria. But, there was no significant correlation between seed morphology and germination parameters in three oak species.