نشریه بوم شناسی جنگل های ایران
پیاپی 9 (بهار و تابستان 1396)

The present investigation was aimed to study the qualitative and quantitative characteristics of Lebanon Oak (Quercus libani Olive.) in Marivan city-kordistan. To investigate the effect of altitude on the qualitative and quantitative characteristics of Lebanon Oak, 108 circular plots of 1000 m2 on three elevation classes of 1400-1600, 1600-1800 and 1800-2000 m were designated. Within each plot, the desired characteristics include: trees diameter at the breast height, height of trees, basal area, crown coverage, quality of trunks, crown symmetry and the status of regeneration were studied. Results showed that DBH quantitative and qualitative characteristics of Lebanon oak trees within the altitude of 1600-1800 m above sea level were significantly different compared with trees located in the altitude of 1400-1600 m. The highest mean diameter at breast height (20.77 cm), trees height (6 meters), basal area (3.75 square meters per hectare) were located in the altitudes of 1600-1800 meters above sea level. The average number of trees per hectare and average crown coverage were 92 and 12% in this altitude, respectively. 37.9% of the trees had a symmetrical crown. Also, about 48% and 52% of the tree regeneration were with the coppice and seed origin in this altitude, respectively. The results also showed that no significantly difference was found between the elevation range for 1600-1800 and 1800-2000 and the suitable elevation range of Lebanon Oak trees regarding to the quantitative and qualitative characteristics was 1800-1600 m.

Quercus brantii Lindl. and Pistacia atlantica Desf. are the most important tree species in Zagros forests, The abundant use of these trees by the inhabitants of the area has led to a reduction in the quality and quantity of these valuable species, as well as the creation of heterogeneous masses.Recognizing the spatial pattern and the interactions of trees can be a key to managerial interventions for the conservation, restoration and development of forests,On the other hand, the continued involvement of Zagros inhabitants in forest areas has created many heterogeneous areas that make it necessary to recognize these areas in order to manage them in order to reduce the impact of human intervention. Therefore, the aim of this study is to determine the spatial pattern and interactions of Quercus brantii Lindl. and Pistacia atlantica Desf. in heterogeneous masses of Zagros forests. For this purpose, an heterogeneous area of 30 hectares was selected in Kermanshah Qalajeh forests and fully was inventoried, A point map of Quercus brantii Lindl. trees and Pistacia atlantica Desf. in the study area was prepared using a distance-azimuth method. In this study, the spatial pattern and interaction of trees was analyzed using univariate and bivariate K2 function. The results of this study showed that Quercus brantii Lindl. trees and Pistacia atlantica Desf. are 85.6% and 9.7% of the trees in the studied area and have a mixed pattern. Spatial pattern of Quercus brantii Lindl. and Pistacia atlantica Desf. changes from clumped to random and from random to uniform with increasing of distance, respectively. Analysis of K2 bivariate function showed attraction in distances of less than 8 meters and the non-interaction of species in other distances.

Landslides caused many ecological processes at landscape to local scales, including the ecological succession processes. The landslides geological characteristics and their management as physical risks are truly documented but the ecological processes that are caused by landslides and their relations to efforts to restore stability to unstable slopes, have not been well studied. In this study, soil mechanical, physical and chemical properties and herbaceous biodiversity of stabilized sliding area in Kheyrud Forest were compared to adjacent non-slide area. To study the properties of soil and herbaceous biodiversity in two areas were used 2×2 m plots. Past software was used to calculate biodiversity indexes and independent t-test in spss was used in order to compare biodiversity indexed and soil. No significant difference was found between soil chemical characteristics and herbaceous diversity in two areas. Results of soil mechanical properties showed that soil of the areas is fine-grained and clay loam (CL). Results generally showed that stabilized sliding area has returned to the original state before the landslide in terms of soil mechanical, physical and chemical properties after about two decades. It seems that in such areas it can be expected that the conditions of biodiversity of the grass are meaningless, and finally, by closing or redirecting the marginal slopes, some soil characteristics can be restored to the proper condition.

Numerical and parametrical indices are two of the most important and most widely used indices for assessing biodiversity in different societies. Nevertheless, their efficiency and selection in various ecosystems has always been one of the challenging issues of ecology. In this study, the numerical indices of diversity, richness and eveness, as well as abundance–ranking distribution models including broken stick, log normal, log series and geometric series as parametrical indices of diversity were calculated seperatly for herbaceous and woody species in different physiogrphic conditions in zagros forest ecosystem. Results showed that there was significant different between various physiographic conditions in term of numerical indices as the Shannon-Wiener diversity and Margalef richness indices of herbaceous species in the northern aspect have a similar trend and the highest values ​​of these indices were on slope of 0-25% and their values decreased with increasing slope. In contrast, the diversity and richness of woody species was higher in south aspect and slope more than 50%. The results showed that, in all physiographic situations, the frequency distribution of herbaceous species is more consistent with the geometric series model which indicates low biodiversity and fragile communities. In the case of the woody species frequency distribution, results showed that the log series and broken stick were the best models on north and south-facing slopes respectively.

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.

The present study eas aimed to evaluate the potential of ALS data in estimation of individual canopy cover area and tree heights for the part of Shast Kalate of Gorgan. In this study 117 tree that located in dominant forest story and without overlay with adjacent trees, were selected. Center coordinates of sample trees were determined using DGPS system. Individual canopy area and tree heights were extracted using in Fusion software. UltraCam-D images were used to separating the canopy border of a single tree and produce a tree polygon. The result of linear regression between individual canopy area and tree heights in the field measurement and ALS data were yielded coefficients of determination , (0.974 and 0.997); RMSE% (6.13 and 7.24) respectively. Mean differences between individual canopy area and tree heights of field measurement and ALS data were achieved 0.72 m and 12.8 . Therefore the results of this study showed that ALS data are capable of estimating of individual canopy and tree heights with high accuracy.

Forests have high environmental, economic and social potential values. Therefore, it is important to protect this ecosystem and prevent any unauthorized interference. The high economic value of forests, including Fandoglu forests, increases the importance of their conservation, in particular their continuous conservation. Ardabil Fandoglu forest is one of the most protective recreational forests in the area. The main collected product of this area is hazelnut. The purpose of this study was to evaluate the income from hazelnut production and the factors influencing the management of this species in this area. The method of this research was a survey of hazelnut and the statistical population of this research includes hazelnut producers in that area. A total of 79 randomly selected hazelnut harvesters were selected to complete the questionnaire. The estimated variables were amount on consumption, sale, economic rent, annual household income, employment and etc. Share of hazelnut income in total household income was 20.3 percent. According to the results, the economic profit and economic rent of hazelnuts was 1397000 rials and 8982710 rials per hectare per year, respectively. Finally, the expectation forest value per hectare from ​​hazelnut production was 17965420 rials. The annual employment amount of the hazelnut production was 19 persons. It has been concluded according the high economical importance of this species at the household economy, it is important to manage this area with consideration of the sustainable harvest rate.