ECOLOGY OF IRANIAN FOREST
Year:2024 | Volume:12 | Issue:2|Papers Count:12

Extended Abstract Background: Currently, forests are not only considered an economic pole but also a support for the survival of other sectors. For this reason, decision-making, as the core of management, is an inseparable part of the tasks of managers and planners in natural resource units. Forest management planning is an important decision-making tool in forestry. The result is a management plan that defines the expected activities, their timing, and their control to achieve the objectives of forest management in a forested area. However, climate change over time affects the biological and ecological conditions of plant communities. Considering the importance of sustainable development, it is necessary to pay attention to this issue to offer solutions to adapt to these changes and reduce the risks. Global climate change is increasing with the rise in temperature and atmospheric carbon dioxide levels, as well as changes in precipitation. These changes also affect forest ecosystem services, growth, harvest patterns, and forest structure, posing new challenges to forest ecosystems. Predicting the future growth of forests and their performance under different scenarios is a key element in planning sustainable forest management. It is also essential to study and model the quantitative characteristics of forests to target the ecosystem toward desirable goals and implement conservation and restoration measures. Therefore, this study aimed to evaluate the basal area growth model of trees under climatic conditions for the next five decades. Methods: This study was conducted in the Jojadeh section of the Farim Forest in Mazandaran Province. This section covers approximately 2803 hectares with elevations between 782 and 1750 m above sea level. The climate of the region was classified as humid according to the Ivanov method. The annual rainfall and average annual temperature are approximately 833 mm and 11 °C, respectively. Forest species include Fagus orientalis, Carpinus betulus, Alnus subcordata, Quercus castaneifolia, Acer velutinum and other species. In this study, circular fixed sample plots (1 are) were established and measured in the deciduous and uneven‑aged Farim forest. A 200 m × 150 m rectangular census was established in the forest. The diameter and tree species of all living trees with a diameter of more than 12.5 cm were measured with calipers. The basal areas of both the trees and thickest trees were two important competitive factors used as independent variables in this study. The trees measured at the beginning of the study period were re-measured and identified at the end of the study period (10 years later). Finally, the forest growth rate and growth model were calculated, analyzed, and modeled using the R software. The relationships between these factors were determined using the growth model of the basal area and the climatic information of the study area. Using the HadCM3 general circulation model data, three scenarios, A1B, A2, and B1, were used to program and analyze the relationship between the basal area growth and climate factors for the next 50 years. Results: The basal area growth model has good accuracy, with a 94% correlation. In addition, the basal area, basal area of the thickest trees, and precipitation were the most important features in the growth changes at the sample plot level. The results of climate prediction for the next 50 years were analyzed separately by species. The results indicate that each scenario creates different conditions for each species, which is an important issue in forest management as each species depends on its biological conditions, and the habitat itself responds differently in the region. Because of the rise in temperature in the region, competition will increase among heliophyte species, and, to the same extent, sciophytes species will be rarely seen in the region in the future. Conclusion: The results of this study can serve as a su itable tool to support management decisions and plans for the conservation and rehabilitation of Syrian forests in line with the effects of climate change. This is because the trend of climatic conditions indicates that torrential rains and floods will likely not increase significantly in Mazandaran province in the coming decades compared to the current and past situation while the temperature increase will take a faster pace. According to the results, the development of vegetation models for the tree basal area is strongly influenced by climatic variables, especially precipitation, which should be considered in forest management. Because climate change is regarded as one of the most important factors for tree growth, it is highly useful to carry out such studies to understand future changes in forest stands under the influence of this phenomenon and to apply them in the management and planning of forests and their management.

Extended Abstract Background: Oriental beech (Fagus orientalis Lipsky) is one of the well-known industrial species of Hyrcanian forests that spreads from the west to east of these forests. Human activities have caused significant damage to Hyrcanian forests, and this issue highlights the importance of identifying factors affecting the structural characteristics of trees, especially beech, for the optimal management of these forests and the restoration of degraded areas. Considering the effect of environmental factors on the structural characteristics (the basal area and number per hectare) and the distribution of trees, the knowledge of their ecological requirements can be used to prepare programs for the protection and development of forests. Previous research about factors affecting the distribution of this species focused on topographical variables and the effects of climate change. Thus, No research has so far investigated the effect of the frequency of fog occurrence on the structural characteristics of this species. Therefore, the effect of topographical variables (height above sea level, slope, and direction), temperature, relative humidity, and fog on the number per hectare, basal area, and the presence of beech species was investigated in the present study using a generalized linear model (GLM). The results of this research and other studies on the future data from the forests of northern Iran can help predict possible changes in the distribution of species, especially beech species, under the effect of global warming. Methods: To carry out this research, beech species data were obtained from the forest inventory data bank in the north of Iran. Because no meteorological station was available for the whole region of Hyrcanian forests, meteorological data were obtained from the POWER project of the National Aeronautics and Space Administration of the USA. Since fog is defined as water droplets suspended near the earth's surface, which reduces horizontal visibility to less than one kilometer, the occurrence of fog was determined using the horizontal visibility index. After preparing the data, first the number of trees per hectare and then the basal area of trees were calculated in each sample plot. The collected data were separated based on the presence or absence of beech. Data were analyzed using GLM and cross-validation evaluation in R software and the caret package. Results: The results of the correlation between the independent variables showed that the amount of precipitation had a significant and high correlation with relative humidity, hence the precipitation variable was removed from the modeling. The GLM showed acceptable accuracy for predicting the number of trees per hectare (R2 = 0.16), basal area (R2 = 0.16), and the presence of beech species (AUC = 0.75). The fog, height above sea level, and relative air humidity variables had a positive relationship with all three traits (number per hectare, basal area, and the presence of beech species) while temperature was negatively related only to the presence of beech species. The aspect variable had a positive and significant relationship with the number of beech trees per hectare and basal area, respectively, but it was not significantly related to the presence of this species. The height above sea level was the most important variable for predicting the number of trees per hectare, the basal area, and the presence of beech species. Relative humidity was the second most important variable for predicting the number of trees per hectare and basal area while fog was the second most important variable for the presence of beech species. The temperature, slope, and aspect had a significance of less than 20%. Conclusion: The reason for the higher relative importance of the height above sea level can be attributed to low temperature and high rainfall as the optimal conditions for the growth of the beech tree; these conditions are directly related to the height above sea level. Our results also determine the importance of relative humidity and the occurrence of fog in the distribution of beech species. The high importance of the relative humidity variable may result from the fact that beech is generally described as adapting to full-shade to partial-shade conditions. Since the northern aspect (in the Northern Hemisphere) generally receives less direct sunlight and is usually cooler, this species usually establishes in the northern direction in the Hyrcanian forest. On the other hand, since relative humidity increases with decreasing temperature, it can be concluded that beech prefers higher relative humidity. In the forests of mountainous areas and near the coast, the number of fog occurrences is high due to high air humidity and altitude. Finally, this phenomenon leads to rain fog and increases the amount of water reaching the forest floor. Therefore, it can be stated that the occurrence and production of fog play a pivotal role in providing the water needs of beech trees due to the high moisture requirement of this species. The high importance of relative air humidity and the occurrence of fog in the distribution of beech species necessitate additional studies regarding the accurate estimation of the occurrence and amount of fog in Hyrcanian forests. Studies on fog and its effects on vegetation, particularly in temperate regions, can provide valuable insight into the potential benefits of fog for this species. Given the lack of studies, it is suggested to investigate the effects of other environmental factors, including soil properties, on the distribution of beech species.

Extended Abstract Background: It is essential to investigate the depth, strength, and main mechanisms of edge effects and recreational activities to preserve species diversity in forest ecosystems. This study aimed to evaluate edge effects and recreation on woody and herb species composition, richness, and diversity in Hyrcanian broad-leaved forests. Methods: Two treatments (control and recreational regions) were determined in the Noor forest park, Mazandaran Province, to achieve research objectives. Five transects from the edge to the forest interior were established in each region. Measurements of herb and tree layers were collected at -5 (out of the forest stand), 0 (forest edge), 25, 50, 100, 150, 200, and 300 m along each transect. In total, 45 sample points were assigned to each treatment. To collect data on tree and shrub canopy cover, two rectangular sample plots of 200 m2 (20 × 10 m) were laid out perpendicular to the transect on the left and right sides at each point. The count, diameter at breast height (> 5 cm), height, and canopy cover percentage were the variables measured in the identified tree and shrub species. For sampling herbaceous species, 10 one-m2 (1×1 m) subplots, with five subplots on each of the right and left sides spaced one m apart, were determined at each sampling point. The type and abundance of herbaceous species were recorded. Using a light sensor device (model Lycor 250), the amount of light entering the forest floor at a height of > 1 m above the ground surface was recorded at each sampling point. The species richness and diversity of tree and herbaceous strata in the sample plots were evaluated using the total number of species present in each sample plot, the rarefaction method, Shannon-Wiener species evenness, and species diversity indices. The SHE method was used to determine the contribution of species richness and evenness to the measurement of species diversity. After calculating species diversity indices, GLM analysis and the Tukey test were used to compare means between treatments. The magnitude of edge influence (MEI) and DEI for all were calculated for species diversity indices and environmental variables. DEI for each variable was calculated using the randomization test of edge influence (RTEI). Data were analyzed with R software version 4.3.1. Results: The light near the edge was more than the interior in the study areas, and the edge positively affected the amount of light. Based on the results of the Rarefaction method and overlap of confidence intervals of the curves related to the study areas, no species richness differentiation was observed between the control and recreational areas. However, the non-overlap of the tree diagrams reveals the highest and the lowest tree species richness in the recreational and control areas, respectively. DEI values of light were -5, 0, 10, and 50 m in the control forest and -5 and 0 in the recreational area. The number of trees per hectare in distances from 10 to 150 m and the volume and basal area per hectare at a distance of 10 m were higher in the control area than in the recreational area. In general, a positive effect of the edge was observed on the species diversity indices of herb and tree layers. The results for the comparison of species diversity indices between the control and recreational areas  showed that species richness and diversity of the herb layer were higher in the distances of 10-300 m of recreational areas than in the control area. In the tree layer, higher species richness was recorded in edges of 10-200 m of the control area than in the recreational area. For the evenness index, DEI values were 10 and 0 m in recreational and control areas, respectively. Moreover, DEI values of herb species richness and diversity were 0 and -5 m in control forests. Conclusion: Based on the results, the forest edge is considered an essential part of the forest landscape structure that significantly affects the structure, functions, and species diversity. Regarding the tourism and recreation industry as one of the largest industries in the world and its increasing importance, it is necessary to understand and improve the knowledge about its effects and the severity of its impact (due to the construction of roads) on different variables for better management and biodiversity conservation.

Extended Abstract Background: The plant biodiversity of any ecosystem is directly affected by its vegetative characteristics and diversity of plant species, which always guarantees the ecosystem’s stability against variable environmental and biological factors. Biodiversity indices are measured to compare the biodiversity of different masses and estimate the changes in biodiversity over time at the mass level. The Hyrcanian forests of northern Iran are a legacy left from the third geological period, and today a large part of them has been destroyed in the plains due to destructive human activities. These forests have a special importance for the protection and management in the south of the Caspian Sea. Hyrcanian boxwood (Buxus hyrcana Pojark.), which belongs to the Buxaceae family, is the only species of boxwood in the Hyrcanian forests of Iran. It has unique values from various aspects, including economics, tourism, preservation of biodiversity, etc. This valuable species has been threatened by human and natural factors for a long time and its area has decreased in the country. The present research investigates the floristic-physiognomic status of boxwood habitats in Cheshme Bulbul, Sangdeh, Si-Sangan, and Shafarood regions. Methods: In this research, the important habitats of Hyrkanian boxwood were sampled from the protected area of Cheshme Bulbul, Bandar Gaz, Golestan province, as the easternmost distribution area of this species in Hyrkanian forests to Shafarood forests in Gilan province. In total, 125 sample plots of 400 m2 (20 × 20 m) were planted in the four identified areas (35, 30, 40, and 20 sample plots in Bandar Gaz (Cheshme Bulbul), Frame (Sangdeh), Si Sangan, and Shafarood, respectively). To measure the herbaceous cover of the forest floor in each sample plot, five small plots of four m2 (2 × 2 m) were walked in the center and four corners of each sample plot to harvest their herbaceous cover. Biodiversity indices, including Shannon, Simpson, and Fisher diversity, Margalf and Menhinik richness, and Pilou, Simpson, and Shannon uniformity, were measured for each of the sample plots. The plants were identified very carefully using the Persian Flora of Iran, the Flora of Iranica, the Flora of Türkiye, and the Flora of Europe. The biological form of any plant was determined and recorded based on the Rankier method. The range of geographical distribution was determined according to the mentioned flora. Then, the belonging of each species to the existing phytochorions was determined and the geographical distribution diagram of the regional plants was drawn using floristic data in the division of the vegetative regions of the earth's surface.  Species diversity between habitats was compared with the one-way analysis of variance. Means were compared using the Tukey-HSD test in SPSS software. Graphs were drawn using Excel software (2013). Results: In total, 186 plant species belonging to 68 plant genera were identified in the studied regions. The hemi-cryptophytes (65 species, 34.94%), phanerophytes (40 species, 21.5%), geophytes (37 species, 19.90%), trophytes (36 species, 19.35%), and cryptophytes (5 species, 69.2%) dominated the vegetation composition of Hyrkanian boxwood habitats. Kamephytes were the rarest biological form in the region with a percentage (3 species). The results of the geographical distribution of plant species in the region showed that the entire flora was mainly of European Siberian (55 species) and multi-regional (38 species) elements, which accounted for more than 50% of the species (93 species). This was followed by Europe-Siberian/Turanian Iran/Mediterranean vegetation areas (25 species, 13.44%), Europe-Siberian/Turanian Iran (25 species, 13.44%), Turanian Iran (16 species, 60.8%), Europe-Siberian/Mediterranean (13 species, 6.70%), and cosmopolitan (8 species, 4.3%) species. The lowest presence in the region was observed for the vegetation areas of Mediterranean/Turanian Iran (5 species, 2.70%), considering that the northern forests are geographically located in the Auxin-Hyrcania state of the Pontic sub-region, which is a large vegetation area belonging to Europe-Siberia. The presence of species belonging to this geographical spectrum in the flora of these regions is not far from expected. Moreover, the presence of species in other geographical areas is a result of the natural patterns of the accidental presence of plant elements from other vegetation areas of the world. Conclusion: The results of this research show higher indices of diversity, uniformity, and species richness in Shamshad Frame and Shafarood habitats, which have a higher average height above sea level than Cheshme Bulbul and Sisangan habitats. The review of the sources shows that physiographic factors play an important role in the indicators of species richness and diversity. Changes in altitude above sea level often lead to changes in environmental conditions, such as temperature, precipitation, and soil characteristics. This diversity in habitat conditions increases its heterogeneity and allows a wider range of species to coexist. As a result, more habitat heterogeneity leads to higher species diversity, which is also reflected in the biodiversity index.

Extended Abstract Background: The leaf area index (LAI) is one of the structural indices of forests and a key variable in the state of forest ecosystems. This index is one of the major structural indices of forests that plays an important role in the processes of evaporation and transpiration and in monitoring the growth of trees. The role of LAI is very important in the changes in the structural quantitative characteristics of forest stands. There is a general relationship between the LAI and the quantitative characteristics of the mass. The leaf area of each tree can be estimated using allometric equations of quantitative characteristics. This research focuses on the effects of changes in the quantitative characteristics, such as tree density (n.ha-1), basal area (m2.ha-1), volume (m3.ha-1), mean height (m), mean diameter at breast height (DBH, cm), crown area (m2.ha-1), and crown volume (m3.ha-1) on the LAI and preparation of their allometric equations in the broadleaf forests of Golestan province. Methods: To collect ground information on LAI, 227 circular sample plots with an area of 1000 m2 with a systematic sampling method and a 100 × 100 m grid were dismounted in five habitats from west to east (Kordkoy, Shasat Kalathe, Zarrin, Gol, Sorkhdari, and Loveh). In the center of each sample plot, the LAI was measured using a leaf harvesting trap with dimensions of 60 × 60 cm. The geographic center of each sample was recorded using a Differential Global Positioning System device. The species type, breast diameter greater than 12.5 cm, the height of trees, large diameter, and small crown diameter are measured, then as tree density (n.ha-1), basal area (m2.ha-1), volume (m3.ha-1), mean height (m), mean DBH (cm), crown area (m2.ha-1), and crown volume (m3.ha-1) located in each sample plot were calculated in each plot. To calculate the LAI, it is first necessary to measure the specific leaf area of all species in the study area. To calculate the LAI, 20 trees were separated from each tree in each habitat and five leaf samples were separated from each tree in four geographical directions. In total, more than 15,000 leaf samples were analyzed and scanned in five habitats. The area of each leaf was measured using ImageJ software. The wet and dry weight and surface area were measured simultaneously using a digital scale with an accuracy of 0.01 and then scanned with a high-resolution scanner. After scanning, the leaves were dried in an oven at 72 °C for 48 hours to obtain their dry weights. Non-linear rational function, Gaussian, hyperbolic, heat capacity, and exponential models were used to investigate the relationship between LAI and the structural characteristics of the stand. Results: The results of the analysis of descriptive statistics showed that the minimum, maximum, average, and standard deviation of the LAI were calculated for 227 samples (1.86, 13.45, 6.33, and 2.33), respectively. The results of the analysis of descriptive statistics also showed that the mean and standard deviation for the characteristics of volume (m3.ha-1), tree density (n.ha-1), basal area (m2.ha-1), crown area (m2.ha-1), crown volume (m3.ha-1), mean height (m), and mean DBH (cm) were respectively (96.96) 298 and 18.205), (24.05 and 12.82), (24.05 and 12.82), (51.148 and 54.155), (2.781 and 05.95), (41.36 and 9.97), and (25.81 and 4.93). The results of the relationships between the LAI and the quantitative characteristics of the volume (m3.ha-1), tree density (n.ha-1), basal area (m2.ha-1), crown area (m2.ha-1), crown volume (m3.ha-1), mean height (m), and mean DBH (cm) of the coefficients of determination showed (36-0.96) R2 = 0.00 with a mean square error of MSE = 0.48-2.06. Among the investigated quantitative traits, the average height, crown volume per hectare, and volume per hectare gained the highest R2 values (0.36-0.96) and the MSE (0.48-2.06) with Gaussian, Richard, and heat capacity allometric models, and the tree density trait (n.ha-1). The lowest R2 (0.36) and MSE (2.06) in the study of LAI were obtained with the Gaussian model. The results also showed large changes in the LAI for the crown volume trait up to 400 (m3.ha-1), followed by a uniform trend. For the average height of up to 40 (m), many changes were found in the LAI. For the volume trait (m3.ha-1), the LAI increased up to 800 (m3.ha-1) and then showed a uniform and even downward trend until 1200 (m3.ha-1). Conclusion: The results of this research demonstrate that the three quantitative traits, viz. crown volume (m3.ha-1), mean height, and volume (m3.ha-1), have the greatest effect on the changes in the LAI. Thus, these three traits can better explain the LAI. The LAI can estimated using the three crown volume (m3.ha-1), mean height, and volume (m3.ha-1) traits. Based on these three traits, the LAI can explained on a large scale, and the estimated results can be used in climate models and the development of appropriate climate change policies.

Extended Abstract Background: Because human and non-human factors are present in most part of the Iranian northern Zagros Forests, an extensive portion of the forests in these areas have been lost or are at risk of destruction, making forestry initiatives increasingly important for the environment. Even enriching the existing forests is a particular approach to dealing with the quantitative and qualitative degradation processes. Furthermore, afforestation is a strategy for recovering degraded areas and is recognized as a method of protecting soil and water, combating desertification, providing wood, and increasing carbon and nitrogen stores. The selection of suitable tree/shrub species based on expert opinion and decision-making model criteria is one of the most effective factors in the success of afforestation and reforestation projects. The current study aimed to enhance the Iranian northern Zagros Forests in the Perdanan area of Piranshahr and to restore its destroyed regions (empty spots) by finding the most appropriate forest tree/shrub species. Methods: In this research, all destroyed spots, clearings, and empty spots of tree and shrub species were first identified and extracted as destroyed spots using the satellite images of 2022 from ESRI and the Google Company. To prepare the homogeneous units of the investigated area in the Pardanan forest lands of Piranshahr (northwest of Iran, the starting point of the Zagros forests), the topographical layers of the area, including slope, direction, height above sea level, geological maps, land ecology, and the map of micro-ecosystems, were combined to prepare the map of the ecological unit (homogeneous units) of the studied area. Because of the existence of destroyed spots, gaps, and empty spots of tree plant species, three one-kg soil samples from a depth of 0-30 cm were prepared from each of the environmental units. The soil samples passed through a two-mm sieve and thensubjected to measurements of soil physicochemical properties, including pH, electrical conductivity, texture, moisture, lime, nitrogen, organic carbon, phosphorus, potassium, calcium, magnesium, bulk density, and particle density factors. The findings of the soil samples were then analyzed with SPSS software to categorize the region based on soil properties by generating a dendrogram of the retrieved parameters using the K-Means Cluster technique. The acquired parameters were split into three good, medium, and poor stands after being separated into distinct groups and identifying the limiting characteristics of the studied region. The best species were selected through an extensive literature review of studies conducted in the area of Zagros forests. A list of 29 species of the most important and best species as final options was prepared and delivered to the questioners, which included university members and forestry experts in Iran. The most suitable species were selected based on the examined criteria and the soil properties of the region. Finally, the introduced species (options) were prioritized independently for each habitat by the TOPSIS method utilizing the opinions of the respondents (university members and forestry specialists in the forest areas of Iran), the AHP approach, and the decision-making criteria (viz. power of adaptation, the cost of keeping seedlings and seeds in afforested regions, water and soil protection, drought and natural element resistance (e.g., wind, pests, fire, etc.), growth rate, and seedling or seed purchase price). Results: The findings of extracting damaged spots, clearings, and vacant spots of tree and shrub species using remote sensing data revealed the presence of 141 places covering a total area of 685 ha. Decomposing the decision-making problem into smaller elements created a hierarchy on three levels. The first level contained the purpose of decision-making, and the second level comprised six criteria (maintenance cost, purchase price, growth rate, resistance, compatibility, and soil and water protection). In the third level, options with 29 native species were examined through a questionnaire among five experts, and finally, the most suitable species (option) was selected for each habitat (good, medium, and poor habitats) determined by examining the results of the sample dendrogram. The soil patches were separated and selected using the TOPSIS method. The results of the TOPSIS ranking technique showed that  Arjan and Ars species were the most preferred species, with closeness indexes of 0.63, 0.65, and 0.64, respectively, in good/medium and poor habitats, respectively. Walnut, sand, and hackberry species (with closeness indices of 0.489, 0.487, and 0.484, respectively) were selected as the most unfavorable species for afforestation and forest restoration in these areas. Conclusion: The adaptability of the selected species for afforestation and forest enrichment projects to the region's current environmental conditions, as well as its low demands in comparison to other tree species, are the primary success factors for these programs. Plants, on the other hand, prefer certain conditions over others based on their biology and ecological demands, such as the quantity of light in different life stages, humidity, bedrock, and soil depth. Knowing these requirements will undoubtedly improve the accuracy of species selection and planting site selection and increase the chances of achieving a satisfactory result. According to the findings of this study, the studied region may be divided into good, medium, and poor stands based on its soil properties, and each of these areas has the necessary potential for afforestation. Nevertheless, given that each species has unique ecological demands, the relatedness of the species' ecological needs to the current ecological circumstances in the region is a prerequisite for the success of afforestation and reforestation projects. According to our findings, native species are the best alternative for recovering destroyed forest areas, and nursing species are more important than climax species in restoring degraded forest areas. The findings of this study can help forest managers plan effective forestry operations, particularly in Zagros ravaged areas (particularly in Iranian Northern Zagros forests).

Extended Abstract Background: Human activities, climate variability, and environmental stress have strongly affected forest ecosystems worldwide. Forest fires are among the major factors of global ecosystem destruction. Fires in the forest, whether of human or natural origin, have been raised as a serious crisis in recent years. Hence, fire risk assessment plays an important role in forest fire management because knowing where the highest risk is essential to minimize threats to resources, lives, and property. Integration of spatial information from different sources using statistical analysis in the GIS environment is a suitable tool for managing and spreading forest fires, which is one of the main natural hazards in northern Iran. Therefore, it is necessary to prepare a fire risk assessment map for the planning and protection of forests. Methods: The current practical research concerning its nature is a combination of documentary, descriptive, and quantitative model-based methods regarding the research method. In this study, fuzzy and hierarchical (AHP) logic models were combined to investigate the risk of forest fire in Mazandaran province in five classes, very high, high, medium, low, and very low, respectively, using four main criteria and nine sub-criteria, namely topography (height, slope, direction, and rivers), climatic factors (peak temperature and precipitation), human factors (residential areas and the network of communication roads), and biological factors (vegetation). To obtain the net vegetation cover, the Normalized Difference Vegetation Index (NDVI) was applied to the Sentinel-2 satellite image set in a 5-year period (2017-2022) in the GEE web system. The height, slope, and slope direction maps of the study area were prepared from the digital elevation model (DEM) of 12.5 m from the ALOS AVNIR-2 dataset. The distance from rivers, residential areas, and the road network was calculated using the Euclidean distance tool in ArcMAP software. The geographic location of meteorological synoptic stations was obtained from the Meteorological Organization, and its information was used as meteorological input data. In the ArcMap environment, a map of average annual precipitation and maximum temperature was prepared from synoptic stations through interpolation for the period from 2007 to 2021. Based on this modeling method, experts' opinions were used for the relative importance and priority of criteria and sub-criteria in the risk of forest fire in the study area to obtain the fuzzy weight of criteria and sub-criteria. Based on the weighting coefficients applied in the present plan, the final weights of the criteria and sub-criteria affecting forest fire from the highest to the lowest weights belong to the topographical, biological, climatic, and human criteria. Among the sub-criteria, the highest and lowest weights belong to vegetation and slope, respectively. The consistency rate (CR) for the matrices of the affecting factors is equal to 6.25%, which is less than 10%, actually indicating that the weight of the criteria is proportionate and reliable. The highest weights were obtained for the vegetation cover and the slope direction, and the lowest weights belonged to the distance from the river and the slope. Finally, the fire risk assessment map was prepared by combining the fuzzy maps of the sub-criteria in GIS. Results: Overall, medium to very high fire risk potential was found in 72% of the studied area. From a total area of about 2373189 hectares, very low (8.4%), low (18.3%), medium (23.66%), high (25.62), and very high (24%) vulnerability rates were identified in Mazandaran province. Higher fire potential was detected in the East and Southeast parts than in other parts of the study area. The aforementioned fuzzy layers clearly show that the height, slope, and amount of precipitation are low and the density of residential areas and the network of communication roads are high in these parts, with high temperatures. In fact, these factors have increased the risk of fire in these areas. In the present study, the highest fire potential was observed at low altitudes, which could have resulted from the concentration of human activities at low altitudes. Moreover, most fires occurred on low slopes in the studied area. The distance layer from waterways also plays a dual role in the occurrence of fire. The results of the model show an inverse correlation between the distance from roads and fire potential. Based on the results of the fuzzy AHP model, the probability of fire increased with the decrease in precipitation and the increase in annual temperature. A decrease in the amount of precipitation causes a decrease in soil moisture and vegetation, elevating the possibility of fire. On the other hand, the increase in temperature causes the drying of vegetation and reduces humidity, thereby increasing the possibility of fire. Conclusion: It can be concluded that preparing a fire risk assessment map can help managers and planners in identifying areas with high potential and in crisis management in vulnerable areas. The obtained fire risk assessment map can be used as a decision-making support system to predict future fires in the study area.

Extended Abstract Background: Forests are one of the complex ecosystems of natural resources with an important role in the environment and multiple production capacities and functions. The benefit of different human societies from these resources in various forms has various effects and consequences. Without accurate and complete identification of all its stakeholders, logical and acceptable results cannot be achieved in decision-making and policy-making. Therefore, it is essential to fully understand the stakeholders (actors) and their identification criteria in line with basic policies for planning, decision-making, and success in this field. Because decision-making in the management of forest resources always faces challenges and is often associated with complexity, immutability, and uncertainty due to the multi-purpose nature of the benefits and services of these resources, the difficulty of monetary valuation of ecological services, and the great diversity of the stakeholders of their services. Therefore, the stakeholders in the fields of natural resources and forests are considered vital components, and their presence and activity in these fields are undeniable and provide a guarantee of success in cooperative management for the protection of forests. The advancement of the sustainable management goals of natural resources and forests is realized by identifying an active presence of key actors and the most important and effective groups involved, i.e. forest producers and users, along with other identified stakeholders. The primary purpose of identifying those involved is the names of all those who can and should have a role in the planning and management process, and their identification is an important part of the participatory planning process because it is considered a part of the prerequisite for participation. Therefore, identifying and determining the stakeholders make it possible to take advantage of their cooperation in a planned way in the implementation and management of forestry projects and to facilitate the implementation process of the programs. Methods: To identify, weight, and prioritize the stakeholders involved in the Hyrcanian forest ecosystem services using multi-criteria decision-making models, the stakeholders involved in the Hyrcanian forest ecosystem services were first identified and gathered based on the review of various studies. Then, the research questionnaire was designed to answer two important questions in this study: a) who are the people involved in Hyrcanian forest areas? and b) what is their priority? Therefore, the beneficiaries of the economy of Hyrcanian forests were identified by designing a questionnaire scored with a Likert scale, designing items with five priority options, and determining the individuals or groups of stakeholders. In this research, the opinions of 50 experts, academics, and experts of the Natural Resources and Watershed Management Organization at the provincial and regional levels were used to identify the beneficiaries of the ecosystem services of Hyrcanian forests. The questionnaire was validated and confirmed by experts, and its reliability was confirmed with a Cronbach's alpha statistic of α = 0.97. The stakeholders of the forest ecosystem services were weighted  with the Step-Wise Weight Assessment Ratio Analysis (SWARA) method, the Simple Additive Weighting (SAW), and Additive Ratio Assessment (ARAS), and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) was used to prioritize them. Results: By analyzing the findings of the questionnaire using experts' opinions, the Hyrcanian forest ecosystem goods and services stakeholders were identified in 19 groups and five levels, such as international, national, regional, stakeholders outside the forest, and stakeholders inside the forest. Based on the results of the weighting of the stakeholders using the SWARA technique, the forest dwellers and communities downstream of the forest edge are among the most important Hyrcanian forest ecosystem goods and services stakeholders with the highest weight, and other stakeholders were placed in the next priorities based on the received weight. The prioritization of the stakeholders of the goods and services of the Hyrcanian forest ecosystem in the TOPSIS, ARAS, and SAW models showed similar results in terms of the prioritization of the stakeholders of the surveyed services. Conclusion: The results of stakeholder prioritization models were compared using the slope of the service weight curve (R2) in three models. The slope of the relative closeness curve of the weights in the ARAS model was a descending exponential function with an explanatory degree of 0.93, which indicated an obvious difference between the stakeholders of Hyrcanian forest ecosystem services. The slope of the curve of the relative closeness of the weights is higher and closer to one in the ARAS model than in the other two models from different points of view. Based on this result and the consensus of some experts, the prioritization of stakeholders in the ARAS model is closer to reality. Therefore, the ARAS model was proposed as a suitable model for prioritizing the stakeholders of Hyrcanian forest ecosystem services. According to the results of this model, forest dwellers, downstream communities on the edge of the forest, and the off-site users of the forests are considered the major stakeholders of Hyrcanian forest services. Therefore, the role, presence, and influence of these stakeholders cannot be ignored in the management of natural resources and the environment, especially in forestry projects, and it is recommended to optimally use the presence of these communities in cooperative forest management. Furthermore, the human relationship with the natural ecosystem should be at the top of policies and comprehensive management of forest resources. It is necessary to support wood planting projects through subsidy policies and to grant facilities and low-interest loans to forest dwellers and communities downstream of the forest edge. Other necessary measures include efforts to reduce deprivations and increase the socioeconomic development of the villages on the edge of the forest, holding training entrepreneurship courses and classes, introducing handicrafts and non-wood products, identifying target markets, and strengthening the marketing network for the export of non-wood products to increase the share of the forest in the growth and economic development of rural communities on the edge of the forest. Employment programs should also be developed for local communities in the forest protection sectors.

Extended Abstract Background: Forest fire is very common in all ecosystems of the world that affects both vegetation and soil and is also helpful in maintaining the diversity and stability of ecosystems. The effect of forest fires and prescribed fires on forest soil is very complex. It affects the organic matter, macro and micronutrients, and physical properties of soil, such as texture, color, pH, and bulk density, as well as soil biota. Fire is a natural factor in the forest that temporarily reduces the vegetation on the soil surface. After a fire, the soil can experience long-term, medium-term, and short-term changes, which are different depending on the type of soil characteristics, weather conditions, duration, intensity, and frequency of the fire. The Zagros forest ecosystem is generally in the coppice form, and these forests are not safe from fire, which constantly affects them. Considering that the long-term stability of these forests depends on maintaining the soil quality, it is essential to investigate the effects of fire on soil properties. This study aimed to investigate the effect of fire on Zagros forests in Kermanshah province, Gahvareh city in the Lerini region. Methods: The studied area is a part of Zagros forests in Kermanshah province, Gahvareh city, the Lerini region located at 34° 10' 35″ E and 46° 34' 28″ N, with an average height of 1468 m above sea level. In this research, the points were determined by measuring with a meter on transects, and they were sampled regularly in specific time intervals (October, November, February, April, and June). The distance between the samples in each row was 20 m and the distance between the rows was 50 m, and three rows were determined in each of the burnt and control areas. Some soil characteristics, such as pH, electrical conductivity (EC), organic carbon, absorbable phosphorus, soil respiration, microbial biomass carbon, substrate-induced respiration, and metabolic quotient, were measured in soil samples. The effect of the treatments on all measured variables was investigated by the two-way ANOVA. Means were compared by Duncan’s Multiple Range Test (DMRT). Data were analyzed using the Windows version of SAS (version 9.4, SAS Institute Inc., Cary, NC). Results: The soil pH decreased with the passage of time and a decrease in air temperature under the crown (unburnt and burned) and outside the unburnt crown. An upward trend in the pH of the soil in these three places occurred after the cold season. The soil pH ranged from 7.31 to 7.66 in all treatments from October to June. The results of the two-way ANOVA showed that the fire and sampling location did not affect the soil EC in different months of sampling. The amount of absorbable phosphorus increased with the occurrence of fire. The highest and lowest amounts of absorbable phosphorus occurred under and outside the burnt and the control crowns, respectively. The range of organic carbon changes indicates that soil organic carbon has increased over time in all treatments. The highest and the lowest increases were observed under the burnt (1.51%) and the control (unburned) crowns, respectively. Examining the changes indicates that the basic soil respiration was high at the beginning of the fire but decreased gradually, and then the initial value also increased in the last months of sampling. In this research, the amount of basic respiration in the soil of burned areas is not higher than that of unburned areas despite the occurrence of fire and the negative effect on soil organic carbon. According to the results, the amount of substrate-induced respiration decreases under and outside the crown (burnt and control) with the passage of time and the decrease in temperature. According to the ANOVA results, the effects of fire and the sampling location were significant on the microbial metabolic quotient of the soil, although no significant interaction effects on the microbial metabolic quotient were observed in February and June. The highest and the lowest microbial metabolic quotients were measured under (0.94 mg C/mg MBC.day) and outside (0.26 mg C/mg MBC.day) the unburned crown, respectively. With the passage of time and a decrease in temperature, the amount of this parameter decreased in the treatment under the crown of the unburnt area and increased in the three treatments under and outside the burned crown and outside the unburnt crown. At the end of the period, the highest and the lowest microbial metabolic quotients were measured under (0.72 mg C/ mg MBC. day) and outside (0.59 mg C/ mg MBC. day) the crown of the burned area, respectively. Conclusion: The results showed that the fire was superficial in both places under and outside the crown and did not significantly affect the soil’s chemical and biological characteristics. Therefore, no significant changes occurred in indicators such as soil organic carbon and EC, and the fire only increased phosphorus in the burned areas compared to the control. Due to the occurrence of surface fire, combustion did not significantly increase biological indicators. The results of this research demonstrate that the fire changes the soil’s chemical and biological characteristics when it occurs with a higher intensity and at a higher temperature.

Extended Abstract Background: In contemporary times, the increasing population growth in large urban areas, industrial development in these cities, and the need for expanding urban green spaces and green belts have drawn the attention of managers to the use and cultivation of multipurpose tree species more than ever before. In many advanced countries, the use of chemical fertilizers has been discontinued in urban green spaces, parks, agriculture, and horticulture. The major reasons for this include undesirable environmental effects, disruption of soil chemical balance and structure, disruption of the ecology of plant and animal communities, and pollution of freshwater bodies. For this reason, the utilization of various organic fertilizers has been highlighted as one of the important strategies in improving horticultural and agricultural production and reducing the risk of environmental pollution, especially pollution of surface and groundwater resources. Humic acid (HA) is among the main types of organic fertilizers and a type of stabilized organic acid derived from the main compounds of humus, considered one of the most abundant organic compounds in nature. The use of HA for plants can directly and indirectly promote better plant growth, thereby increasing production levels and improving crop quality. Therefore, the present study aimed to assess the possibility of enhancing the growth and viability components of white mulberry seedlings as the most commonly used tree species for planting in the green belt of Mashhad using HA fertilizer and animal manure. Methods: For this research, two-year-old and uniform-sized mulberry seedlings were prepared as bare-root. Then, they were transferred to prepared beds in the green belt nursery of Mashhad for planting in pits with planting distances of 1.5 × 1.5 m in a completely randomized design. In five separate experimental plots, the nursery soil was thoroughly and uniformly mixed with animal manure. Subsequently, HA fertilizer in liquid form (at 50 and 300 mg/l) was mixed with the soil in two plots in addition to the animal manure. In the other two plots, foliar spraying at 50 and 300 mg l-1 on the leaf surfaces of the seedlings was carried out at the beginning of the growing season. Only animal manure treatment was considered for the seedlings in the fifth plot. Ten seedlings were selected for each treatment as replicates for examination. The seedlings were irrigated uniformly throughout a six-month growing period for measurement purposes. The growth and physiological characteristics of the seedlings, including plant height, collar diameter, root length, leaf and branch numbers, dry weight of aerial and root parts, gas exchange rates, photosynthesis rate, and seedling survival, were measured and statistically compared after 6 months of applying the treatments. To measure biomass, the seedlings were carefully removed from the soil, and the soil was washed from around the roots, followed by counting the number of branches and leaves. Each seedling was then divided into two parts of roots and stems, which were dried at 70 °C for 48 h and weighed using a digital scale. Finally, the data were analyzed in a completely randomized design, and their means were statistically compared using Tukey's test. The gas exchange rates (stomatal conductance) and photosynthesis rate in outdoors and under natural conditions of temperature, light, and relative humidity were measured using a portable device for gas exchange measurements. For this purpose, 3-6 mature leaves were selected from each replicate. All measurements were conducted between 9 am and 12 pm on a sunny day with a light intensity of 1400 µmol m-2 s-1. Results: The HA treatment added to the soil at a concentration of 300 mg/l resulted in the highest average values of the variables, namely the highest values of radial growth (3.2 mm), sapling height growth (35.1 cm), number of leaves (45), number of branches (16), dry root weight (31.3 g), and shoot weight (38.1 g). A comparison of physiological variables, such as photosynthesis intensity (14.5 μmol m-2 s-1) and stomatal conductance rate (0.23 mol m-2 s-1), revealed that the treatment with 300 mg/l of HA added to the soil led to the highest values. Subsequently, the treatment of 50 mg l-1 of HA added to the soil and then foliar spraying with an HA solution of 300 mg l-1 showed better effects than the other treatments. Overall, increasing HA in the soil resulted in better performance than foliar spraying on the leaf surface of white mulberry seedlings. Animal manure created the lowest averages in all evaluated variables. Conclusion: The positive effects of HA on plant growth and biomass are attributed to its ability to increase water and nutrient absorption by plants, as well as its pseudo-hormonal effects on plants. Based on the results of the present study, HA application positively influenced growth characteristics, photosynthesis intensity, and biomass increase (variables such as leaf number, branch number, sapling length growth, radial growth, root growth, and aerial parts growth). Therefore, adding HA fertilizers to the soil during mulberry planting is highly recommended in urban green spaces, horticulture, and urban green belts.

Extended Abstract Background: In the third millennium, the consequences of human intervention in forest ecosystems have been revealed more than ever. Today, the protection of forest ecosystems is essential not only in our country but also for the entire world of humanity. This importance comes from the fact that human life is basically tied to forest ecosystems, and a healthy person cannot be imagined, except in clean and healthy forest ecosystems. An issue that has unfortunately been neglected with the departure of mankind from the path of balance and has been unwisely and shortsightedly forgotten with the expansion of the process of industrialization and the growth of human technology and knowledge. The damage posed to the forest ecosystem during the past decades is by no means comparable to the previous ones and has posed human society to destructive and fragile crises. Encroachment of government agencies on public property, arbitrary seizure of natural resources by various institutions, production of non-standard cars by government factories, failure of the Environmental Protection Organization to protect protected areas, and the like can be the subject of complaints and lawsuits of non-governmental organizations in the Court of Administrative Justice. This research aims to identify the principles of rights related to forest ecosystems using the Delphi method and interpretive structural modeling to answer the question about the relationships between these principles. Methods: The Interpretive Structural Modeling (ISM) method was used to identify the principles of ecological rights of forest organisms and stratify and interpret the relationships between indicators. As one of the system analysis methods, ISM is based on nonparametric methods and the frequency mode. The main principles of rights related to forest ecosystems were initially identified using the opinions of specialists and experts in this field and by reviewing the research conducted on environmental rights and forest ecosystems. The statistical population consisted of 40 experts in the field of law and advocacy. In the next step, the Delphi method was used to reach group consensus. To carry out this method, questionnaires in the form of a Likert scale were distributed among the statistical population on four occasions. In this questionnaire, the experts were asked to specify the importance and priority of each principle on a scale of 1-5 (not important to very important). In the next step, a questionnaire was distributed among the statistical population aiming at examining the mutual effects of the principles proposed in pairs, as well as the influence and effectiveness of these principles on each other. The mode of opinions was used to reach a consensus among the experts, and the Structural Self-Interaction Matrix (SSIM) was made from the results of the answers. After that, the final matrix of structured self-interaction was made using the mode of experts' responses. Then, the primary access matrix was obtained by transforming the SSIM into a two-valued matrix (0 and 1). After forming the initial access matrix, the final access matrix was formed by intervening transferability in the relationships between the variables. Thereafter, the indicators were ranked using the final access matrix by defining leading and last or accessible sets. After determining these sets, the indicators were ranked and the final matrix of the ISM diagram was drawn based on the determined levels. Finally, the MICMAC method was used to analyze the obstacles. Results: To analyze the indicators of civil responsibility in the rights of forest ecosystems, 18 out of 30 identified indicators were selected using the Delphi method and experts' opinions. The prioritization of civil responsibility indicators in the rights related to forest ecosystems according to the results of the Delphi questionnaires (second and third stages) showed that the least and utmost importance levels belonged to the principles of non-retroactivity and sustainable development, respectively. The selected indicators were the no-harm rule, the waste rule, the attribution rule, the theory of fault, the general rules of civil liability in accordance with Article 1 of the Civil Liability Law, and the principles of non-harmful use of land, prevention, sustainable development, commitment to Cooperation, information and assistance in environmental emergencies, duty and generality of protection of forest ecosystems, exploitation of forest ecosystems, sovereignty over natural resources, the necessity of protection, payment by the polluter, responsibilities Common but different, participation, dealing with environmental damage at the source, and common concern. The results showed that all indicators of civil responsibility in the rights related to forest ecosystems, except for the rule of waste (influence power 10) and the principle of payment by the polluter (influence power 16), possessed an influence power of 18 with the most effectiveness. The results of the final access matrix and the power of dependence (the effectiveness of each indicator on the other indicators) showed that all the indicators, except for the principles of sustainable development and governance over natural resources (power of dependence 16) had the power of dependence values of 18 and 17. Conclusion: The principles of civil responsibility in the rights related to forest ecosystems, including environmental rights, international environmental rights, and forest rights, can have mutual effects that affect the management of natural resources and the protection of forest ecosystems.

Extended Abstract Background: Road construction in the forest causes changes in the microclimatic and biological conditions of the roadsides, which lead to positive and negative consequences. Forest fragmentation leads to the creation of smaller habitats and changes in the ecological reactions of the forest, which are different at the distance from the road. These types of changes are called marginal effects. Marginal effects on tree growth indices are different and have been reported from positive to negative in many studies. A review of research records indicates that a few Iranian studies have investigated the marginal effects of forest roads on chlorophyll and carotenoid contents in leaves. Therefore, the current research intends to determine the consequences of forest roads in a part of Zagros forests by examining the marginal effects of forest roads. The contents of chlorophyll a, chlorophyll b, carotenoids, and the specific leaf area index (LAI), as well as the relative humidity of leaves and pollution caused by traffic and the amount of chlorophyll lost in leaves, were evaluated in this research. Methods: To evaluate the positive and negative consequences of road construction, specific LAI, leaf relative humidity, chlorophylls a, b, and carotenoids in leaves, and the amount of leaf pollution caused by dust were studied in the Shoy Forest of Baneh City, Kordestan province. The climate of the region is semi-humid based on the Dumarten climate factor. To carry out this research, a forest road with heavy traffic passing through these forests was selected and three transects were made at a distance of 100 m perpendicular to the road on both sides. At different distances from the road (0, 50, and 100 m), samples of oak (Quercus infectoria Olive.) leaves were collected along the transects. In each transect, the first sample plot of 10 × 10 m was adjacent to the road, and the second and third sample plots were located at distances of 30 and 50 m from the road, respectively. In each plot, leaf samples were collected from all parts of the crown, including infected, damaged, and healthy leaves. The contents of chlorophyll a and b and carotenoids were measured by the Avon method. Oak leaves were taken to the laboratory immediately after collection and their fresh weight was calculated using a digital scale (accuracy of 0.001 g). The surface of the leaves was measured by a leaf surface meter, and the humidity of the leaves was calculated through the weight relationships of the dry and wet weight of the leaves. The total means were compared with the one-way analysis of variance (ANOVA), and the group means were compared using Duncan's test. All statistical tests were performed using SPSS software Ver. 22, and graphs were drawn with Excel software. Results: The marginal effects of road construction on the specific LAI showed that the value of this index decreased with increasing distance from the road, and the highest value was observed at distances of 0 and 50 m from the road. The highest leaf relative humidity was measured at a distance of 50 m from the road, and there was no significant difference at the edge and at a distance of 100 m from the road. No consistent trend was observed in the relative humidity changes, but this variable noticeably decreased on the roadside, which seemed probable. The results of the effect of road construction on the leaf chlorophyll a and b contents showed a decrease in thisvariable with increasing the distance from the road, and the maximum chlorophyll content was obtained at zero distance from the road. Moreover, the highest leaf carotenoids were recorded at distances of 0 and 50 m from the road, and the lowest amount was observed at a distance of 100 m. According to these results, the forest road construction has reduced the light competition between the trees, and those near the road contain more chlorophyll, which can lead to an increase in leaf photosynthesis. The highest contents of chlorophylls a and b were obtained at zero distance (2.01 and 0.97 mg/g of fresh weight, respectively), and carotenoids (0.15 mg/g fresh weight) were maximal at a distance of 50 m from the road, which was not significantly different from carotenoids in the zero distance (0.14 mg/g fresh weight). The results of dust volume caused by the traffic of vehicles showed more pollution of leaves (0.845 g) on the roadside while a leaf contamination level of 0.13 g was recorded at a distance of 100 m from the road. The present findings on the effects of road construction on the amount of chlorophyll lost in leaves showed a significant difference in this variable only at a distance of 0 m from the road, but these differences were not significant at distances of 50 and 100 m from the road. Conclusion: Overall, the marginal effects of forest roads in the investigated area were positive regarding the contents of chlorophylls a and b and carotenoids, as well as the specific LAI, while these effects were negative in terms of pollution. The lost amount of chlorophyll in leaves and the leaf relative humidity index demonstrate the negative consequences of road construction.