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Drought is the major environmental stresses that it can have a negative impact on plant growth. The study of gas exchange under drought stress can help to identify factors affecting stress resistant. Due to this fact that Zagros forests has Mediterranean and dry climate, with the aim of this study was to assess the impact of drought on leaf gas exchange in two oak species (Quercus brantii and Quercus libani). Water stress consisted of four levels of water stress (100%, 70%, 50% and 30% FC) in the greenhouse situations. Those seedlings were intended for water stress weren’t irrigated to reach to the desired field capacity (70%, 50% and 30% of field capacity), but control seedlings were irrigated every day in order to soil water content at field capacity shall be kept 100%. Results showed that water stress treatment has a significant reduction of stomatal conductance, photosynthesis, conduct mesophilic, carbon dioxide emission, and transpiration. Also Quercus libani showed higher level of photosynthesis, water use efficiency and transpiration than Quercus branti. Overall, results in both species, showed stomatal and non-stomatal limitation would cause of photosynthesis reduction. Also, due to higher water efficiency and lower gas parameter variations, Quercus libani would gain better mechanism of waster stress and Quercus brantii would gain the use drought avoidance mechanism.

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Considering the importance of forest structure and interaction among different tree species, this study conducted aimed to determine and compare spatial pattern, heterogeneity, and dimensions of Hawthorn and Maple trees with other neighbor trees. For determining Hawthorn and Maple trees structure, 30 individual of each trees were identified and studied. Based on the results, uniform angle index for Hawthorn and Maple trees were 0/744, and 0/733 respectively, which would propose a clumped pattern for these two species. Computed mingling index values for Hawthorn and Maple were 0/877 and 0/955 respectively that show a high tree species mixture. Also, the average of crown canopy differentiation and crown canopy dimension were 0/582 and 0/322 respectively, for Hawthorn tee and it was 0/42 and 0/656 respectively for Maple tree. Based on mean values, these results show that Hawthorn had high level of differentiation but was inferior in comparing to its neighbors whereas Maple has intermediate differentiation and is dominant to the other neighbors. The average distance to nearest neighbors for Hawthorn and Maple were calculated 7/374 and 6/278 respectively. The results of an absolute discrepancy algorithm (AD) showed a high differentiation of Hawthorn and Maple mixture in comparing to the other indices. It is concluded that maple is superior to hawthorn in dimension and because of low frequency of these two species, they hold high values of mingling indices.

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In this study, the impact of land use change of forest areas to forest parks on species diversity indices in Chaghasabz Park (Ilam city) has been investigated. For this purpose, three regions in 30-hectare areas were considered, including the area, without, medium and intensive recreation. The field data were obtained using 20 sample plots with each plot covering an area of 400 m2 in a systematic random design (150 m×100 m) in each region. In order to record the herbaceous species, cover percentage for each herbaceous species was recorded in four micro-plots (1.5 m× 1.5 m) that were defined with Domin criterion. In order to evaluate plant diversity, biodiversity indices e.g. Shannon and Simpson and Maguran richness indices were computed. Also, for studying the comparison between the averages of plant diversity indices, Dunken analysis was used. The results showed that in areas without, average and intensive recreation, there were 29, 45 and 21 species respectively. Therophytes were dominant vegetative forms in all three areas. Asperula odorata, Centaurea irritans Wagentz. Marrabium vulgare L., Phlomis olivieri Benth. and Picnomon acarna (L.) Cass were not observed in intensive recreation region. The least shannon and Simpson diversity and richness indices were observed in intensive recreation region, but on the contrary, evenness index was substantial in intensive recreation. We concluded that  intense increase of recreation in forest region might cause a loss species diversity.

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Rural households’ involvement in forest conservation and reforestation depends on their perception towards forest perceived benefit which is attributed to demographic characteristics of the households head. In order to test this hypothesis, a study was run on rural households surrounded by Chahartagh forest reserve (N=600) which its livelihood was based on forest resources. About 196 rural households were determined as the research sample using Cochran’s formula through Simple random sampling procedure. Also, a researcher-designed questionnaire was used to collect data which its content validity confirmed by expert opinions and its reliability confirmed by Cronbach alpha coefficient. Collected data were analyzed by two software of IBMSPSS21 and LISREL8.5. The results showed that rural households’ perceptions towards forest are directly related to benefits they perceived from the forest. Perceptions towards forest benefits was summarized into three categories of perceptions towards forest economic, environmental and social benefits which economic benefit was recognized as the most important benefit perceived by respondents. From rural households’ perspective, the income gained from timber and non-timber products were the most important economic benefits of forests. Structural equation modeling results also revealed that rural household’ perception towards forest benefits differ among rural households according to their demographic characteristics. It observed that the younger, higher literacy level, had the higher income level and also, they had the more positive perception toward forest benefit. Also, each household’s head that was member of rural local institutions, had a corporation with NGOs and had participation into active groups to conserve forests had more positively perceived forest benefits.

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The purpose of this study was to identify the barriers of local peoples' participation in forest conservation plans. The research population included 240 Local rural households in Gilan – e – Gharb, Kermanshah. A number of 144 people were randomly selected using Morgan's sampling size table. A questionnaire was used as a main tool in this study. The content and face validity of the questionnaire was verified by a panel of experts. The reliability of the questionnaire estimated by Cranach's alpha coefficient (0.737). Factor analysis was used for finding the most important barriers. Four key factors were identified as the most important barriers in people participation programs in forest conservation plans. These factors were socio-cultural, economic, organizational and educational barriers. 

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Oak decline is a complex phenomenon that oak forests are faced with it across the world and Iran. Shalam forested area located in north of Ilam province was selectedto determine the role of topographicand some edaphic factors in tree mortality happened in Persian oak forests. The study region was divided into 20 homogeneous topographic units. Within each homogeneousunit,three 0.1-haplots  were randomly-systematically established for measuring the rate of tree mortality and oneprofile was prepared for characterization ofsome  physical and chemical soil characteristics (texture, moisture content, TNV%, OC% and N for each soil layer, and soil depth). In each plot,diameter at breast height (DBH), maximum and minimum crown diameters, crown dieback percent, origination and form of trees and shrubs for all species and site variables weremeasured. Results showed that 15.7% of forest stock had reduced while 97.65% of it belonged to Persian oak species. The results of multiple linear regression and RDA showed that tree mortality was significantly affected by elevation and aspect, but not by slope. The highestrate of tree mortality was observedin high elevation and south and west aspects. Also the results of multiple linear regression and RDA showed that tree mortality was significantly affected by soil depth and texture. So, the highestrate of tree mortality was observed in soils with less depth, less sand% and more silt%. It was concluded that topography and soil have effective role in tree mortality and its expansion across Zagros forests. Identifying the critical conditions in terms of topography and soil in these forests can help and be useful in the management of tree dieback.

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Phenology studies can be appliedin sustainable management, protection, rehabilitation, development, and utilization of forest resources. In this study, the phenology of  Persian oak was investigated in three forested areas of Mamasani, Dasht-e-Arjan and Kamfirouz with 2300 m,2100 m,1800 m altitude, respectively in south –west and north of Fars province, Iran. In each area, ninetrees were visited repeatedlyat different times in different seasons during 5 years (1998-2002) and the observed characteristics were recorded. The results showed the stages of growth were completely different at the threementioned areas. The shoots sprouted up in the second week of March to the first week of April. The full leaf formation happened in the second week of April to the fourth week of April. The early flowers appeared in the second week of March to the fourth week April. Pollination occurred in the third week of March to the third week in April. The leaves began to fall in the fourth week of October to the fourth week of December. So characteristics of phenology in Persian oak were affected by climate and environmental factors.

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Background and purpose: In recent years, forestry projects have gained increasing environmental, economic and social importance as an indicator of development. These projects are one of the most important international activities. Since the establishment of a natural forest in arid and semi-arid regions is a long and complicated process, it is difficult and necessary to restore a deforested forest in these areas. The harsh conditions and nature have reduced the forest ecosystem, so this study aims to present a picture of the status of the current forestry plans with Amygdalus scoparia Spach in four regions of central Bazoft. The intention was to compare the qualitative and quantitative status of forestry in these areas and tested the viability and adaptability of tree and shrub species cultivated in the valleys around the Bazoft river and in the central Bazoft region.
Materials and methods: In this study, the centers of sample plots were 400 m² ((20 × 20 m) in a completely randomized design. In total, there were 153 plots, and in each sample plot, quantitative characteristics such as mean area of ​​canopy, average height and qualitative characteristics such as vitality and the most important characteristic and survival was estimated. Kaplan-Meier estimator was used to estimate Survival Distribution Function, average survival rate and drying risk in each forest area. The same survival function tests associated with this estimator were also performed to ensure probable segregation of the areas. Analysis of variance was performed in regard to classified factors of the region (in four classes), planting time (in four classes: 1385, 86, 87, 88), Front (in four classes: Four main directions), slope (in two classes: more than 25 Percent and below), elevation and density of primary seedlings. Mean values ​​were compared by Tukey test.
Findings: The results of the comparison of survival rates showed that at a small spatial distance, a significant difference was observed in forestry with a singletree species. The highest survival rate after one decade was 0.88 and the lowest was 0.64. Even two identical tests of survival function i.e. Log-rank and Wilcoxon showed that there was a significant difference between forested areas with Amygdalus scoparia species. Cox Proportional Hazards Model using topographic factors (slope, front and sea level) as covariance using Wald statistic showed that the highest Amygdalus scoparia cultivation risk ratio were the western and northern fronts and then low slope regions.
Conclusion: There was a significant difference between forested areas with Amygdalus scoparia species. Based on the average canopy area, height and freshness of the trees, the southern slopes were perfectly suitable for cultivation, and the western and northern slopes were inappropriate for cultivation of these trees. The other topographic factors that probably influenced the success of the Amygdalus scoparia cultivation (slope and elevation) had not significant effects on the outcome of the Amygdalus scoparia cultivation.

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Background and purpose: Various factors affect the occurrence, spread, and controllability of forest fires. A hazard fire zones map can be obtained by knowing the important influencing factors. This map shows fire severity in different zones and stages which provides a suitable tool for managing, preventing, and reducing the damages caused by fires to the natural resources manager. This study aims to prepare fire hazard severity zones based on the range of these environmental factors in the forest areas of Mamsani and Rostam counties in the northwest of Fars province with an area of 2188.7 square kilometers.

Materials and methods: The environmental criteria that were used in this study include elevation, slope, slope direction, distance from the road, distance from residential areas, distance from agricultural lands, average annual temperature, average annual precipitation, and land use. After collecting data from different sources, the fuzzy concept was applied to standardize the criteria by using different fuzzy membership functions. A hierarchical analysis process (AHP) was used to weight the criteria and prioritize them. For this purpose, a questionnaire was prepared, and criteria were scored by experts. All the weighted criteria were overlayed by weighted linear combination method (WLC). To obtain the weights of the criteria, the data obtained from the questionnaires were extracted and analyzed in the Expert Choice software. Each of the selected criteria was also prepared as a map using the geographic information system (GIS) in the ArcMap software environment. Finally, the fire severity risk map was prepared in five categories of very high, high, medium, low, and very low fire severity zones.

Findings: The results show that the burned areas show a high compliance of the implemented model with the existing situation. Among the studied factors, the three main factors of fire in this area are distance from agricultural land, distance from road and distance from residential areas with relative weights of 0.254, 0.1971 and 0.1786 respectively. The results showed that the most fires occurred in the 1500-1900 elevation class and 0-10% slope class. As the slope increases, the rate of fire has decreased. Also, the southern aspect has been prone to fire.

Conclusions: So, it can be concluded that most fires have occurred in areas where human access to those areas is more and easier and other factors are less important. Also, the results of this research showed that forest fire risk zone mapping can help managers prevent fire in different forest areas.