مجله پژوهش و توسعه جنگل
سال نهم شماره 4 (زمستان 1402)

Centralized and top-down decision-making are increasingly insufficient to address local natural resource governance concerns and demands. As a result of the failure of state forest management, governments and allied organizations have been obliged to shift their policies and programs toward participatory (people-oriented) forest management. After realizing the limits of forest monitoring regulations, participatory approaches to forest management employ top-down decision-making methods. Academics, institutions, and governments have all accepted cooperative strategies in recent decades, and they have been implemented in various ways based on geographical diversity, socioeconomic conditions, cultural values, traditional beliefs, general attitudes, implemented policies, and institutional specifics. This study aimed to find out the attitudes of Sardasht city's forest stakeholders toward participatory management.

This research focused on Sardasht, a city in the south of West Azarbaijan province. The study technique is exploratory in terms of practical goal and descriptive-survey in terms of data collection, which was acquired using the Q method to determine the varied mental patterns of stakeholders on cooperative forest management. The Q approach is used to explore people's inner believed in an ordered and statistically interpretable approach. This strategy combines qualitative attitude surveys with the statistical rigor of quantitative research methods. The Q method was used for this study owing to the subject's heterogeneity and the significance of stakeholders' perspectives on forest management in Sardasht city. This procedure began with the collecting of the discourse space and culminated with the acquisition of Q research data, or sorting. This study's statistical community consisted of 29 individuals, comprising all Sardasht forest stakeholders such as villagers and forest residents, natural resources professionals, and university academics. The following stage included the participants identifying and prioritizing 49 concepts based on the provided cards.

The research findings, as well as the number and categories of participants, revealed both variances and similarities in their range of thoughts and perspectives about participatory forest management. As a result, with the goal of researching Q and the criteria of interpretability of variables or groups, three types of participants' mentalities and viewpoints were identified with a strong correlation value. According to the findings and outcomes of Q's factorial analysis, various stakeholders exhibit three distinct mental patterns: protection with alternative livelihood, absolute protection, and participatory management with alternative livelihood. The first attitude demonstrates that individuals in this category understand the necessity of forest conservation, but because the livelihood of many households is dependent on the forest, they wish to better their situation by finding additional employment. However, their living situations will improve in relative terms. Beneficiaries in the second group believe that combining management and protected areas is a good method to conserve Sardasht forests. This is because the most major cause of forest degradation in the region is the conversion of forests to agricultural lands, and this effort lays the groundwork for the progressive loss of natural resources. A third attitude among local stakeholders is a combination of participatory management and alternative livelihoods. What is significant and obvious in this mentality is that the stakeholders accept the change of the current management style to participatory management; however, a complete and comprehensive review of it should be done first, and all of its aspects should be weighed. Finally, cooperative management should be accepted as the only main solution for natural resource.

The current study makes a major addition by modeling the mental models of the drivers using a qualitative and subjective method, emphasizing the perspectives and ideas of participants in the field of Zagros Forest management in Sardasht city. Local stakeholders' perceptions are an important component of a sound decision-making process since they engage directly with natural resource reserves and are the first to experience both their advantages and problems. As a result, their attitude, perspective, and involvement in management and policies should be considered. According to the final results, local stakeholders in Sardasht favor the conservation of Zagros forests. Furthermore, creating employment and alternative livelihoods, as well as expanding market access, can help to ensure the long-term management of forest resources by including local populations in decision-making processes. This range of perspectives emphasizes the importance of developing active and adaptable natural resource management systems.

Due to ecological and biological importance of fine woody debris (FWDs) in forest ecosystems, it is essential to be clarified influencing factors on the FWDs volume stock through appropriate model. One of the models can be decisively efficient for optimal management and control of the FWDs volume stock is the ordinal logistic model. It is expected that the FWDs have a significant contribution in the Hyrcanian forests where different types of plant communities and trees are widely distributed across altitude gradients. Thus, the aim of this research is to use rank logistic analysis to examine the impact of various factors on the volume accumulation of the FWDs in relation to the altitude gradient of the Khairudkanar research forest.

The current study was conducted in the Kheiroud forest using the cluster sample plots implemented along the altitude (100- 1800 m). A total of 12 samples were arranged in an altitude gradient from sea level. These samples consisted of three circular plots, each with a radius of 7.32 meters. The circular plots were positioned in the form of a triangle, with azimuth angles of 0, 120, and 240 degrees. Additionally, another sample with the same area was placed at the center of this design. The distance between each of the circular plots in the cluster was 36.6 meters. In this study, the placement of sample plots was conducted randomly within the specified altitude range, with an interval of 150 meters. A total of 36 clusters were established, comprising 144 samples, within the research forest. These samples were categorized into three diameter classes for the FWDs: 1-2.5 cm, 2.5-4.5 cm, and 4.5-7.5 cm. To measure the diameter of these small dry trees, a linear transect was executed from the center of each circular sample plot. The transect had a fixed azimuth of 150 degrees. Specifically: The diameter layer within the range of 1-2.5 cm was measured at a distance of 4.27-1.6 meters, and For other diameter layers, the measurements were taken at distances ranging from 7.32 to 7 meters. Ultimately, a total of 4.27 meters were harvested during this investigation. During the evaluation process, a transect line was used to measure the FWDs diameter whose central axis was obstructed by the line. Additionally, the type of species, the decay or lack of decay of the FWDs were also recorded. However, the length of these FWDs was not measured in the field due to the evaluation method used. In the analysis, we employed Spearman’s test and calculated Spearman’s correlation coefficient. Additionally, we utilized Chi-square statistics and the dimensions of the consensus table to evaluate the significance of correlation intensity between variables. To model this relationship, we included all uncorrelated variables as input variables, irrespective of any co-linear relationships among the factor variables. Nominal and rank variables were introduced as factors with fixed effects, while quantitative variables served as side variables during the implementation of rank logistic analysis. To validate each model, we assessed various variables using the model fit index. Additionally, we considered the pseudo-explanation coefficients. The significance of the model and its calculation coefficients was examined using the Wald statistic. Furthermore, we evaluated the model’s accuracy in relation to estimated values and observations using Pearson and standard deviation tests.

The research findings indicated that the average volume of the FWDs per hectare in the studied forest was 2.14, 6.01, and 16.23 cubic meters for the first, second, and third diameter classes, respectively. The results of logistic analyses based on the log-likelihood test (X2= 0.06; P > 0.05) and pseudo-R2 (Pesudo-R2 = 0.001) showed that the altitude gradient has no significant effect on the volume accumulations of the FWDs in different diameter classes. According to the Cramer's V and Spearman correlation tests, the results demonstrated that altitude gradient significantly correlated with the stand types, aspect, species and decay of the FWDs in the study forest. Moreover, the results obtained using Kramer's correlation coefficient to eliminate the effects of collinearity between input variables indicated that there is no significant relationship between the aspects and the species, and decay classes. Also, there were no significant correlations between the stand type and decay, and the FWDs species. Taking into account the non-collinearity and variance inflation factor (VIF), the final results of modeling showed that the FWDs species and decay have only significant effects on variations of the first diameter class of FWDs volume stock (Pesudo-R2= 0.24; P < 0.05; X2= 22.61).

On the basis of the Wald test, effects of the FWDs species were similarly significant, and the FWDs decay was inversely significant in association with the FWDs first diameter class response (P < 0.01). It appears that the amount of volume accumulation of the FWDs in thicker diameters was not affected by the factors that were introduced. This implies that many unforeseen events, such as natural disturbances of varying scales and intensity, as well as the inherent nature of forestry - including developmental stages - may be the foremost factors that significantly impact the volume inventory of the FWDs in the thicker diameters.

Hyrcanian forests are very important in terms of preserving genetic reserves and the existence of some plant species that are unique to this vegetation area. Therefore, further investigation of the characteristics of these diverse forest communities for the purpose of ideal management and multi-purpose planning, with the aim of maintaining diversity in these forests, is always an inevitable necessity. Among these features is the dynamics of the structure, which affects the functioning of the ecosystem and is corrected by forest management and natural disturbances. Understanding its structure and dynamics through predicting the future structure of the forest and its evolution is very important for implementing management goals, reducing forestry costs and increasing the productivity of forest ecosystems. Based on this, this research was carried out with the main purpose of investigating the structural diversity of development stages in the managed eastern mixed beech forests.

a 10-hectare area in the managed stands of parcel No. 514, series 5 of the Safaroud forestry plan, which has 42 mosaics of initial, optimal and decay development stages, which are separated based on the indicators and criteria for determining the development stages in forest were identified and selected regardless of its size and shape. The trees inside each mosaic were numbered and measured with full callipering method. The location of all the trees with a diameter at breast height (dbh) greater than 7.5 cm was recorded using the distance and azimuth of the bases relative to each other for each tree. After numbering the trees, characteristics such as dbh and total height of the trees were measured. Then, based on the dbh, the trees were divided into four classes: small (less than 35 cm), medium (35-50 cm), large (50-75 cm) and extra large (more than 75 cm). To quantify the structure of each mosaic in the studied stands, a set of different structural indices was used based on the three characteristics of spatial pattern, mingling and dimensions of tree. After analyzing the data, the structural characteristics of the stands, including the indices of diameter and height differentiation, uniform angle, mean distance to the nearest neighbor, mingling and Clark and Evans index in the mosaics were calculated. Uniform angle and Clarke and Evans indices were used to check the diversity of tree spatial patterns. Also, to check the species admixture, the mingling index was used, and to check the diversity of tree dimensions in each development stage mosaic, the diameter and height differentiation indices were used. The density of trees was also measured using the distance index to the nearest neighbors. Analyzes related to the type of distribution of trees and the type of mixing in the studied stands were done using Crancod software (ver. 1.4).

A total of 3105 trees of beech and other tree species were identified and recorded, and their quantitative characteristics were presented according to the mosaics of development stages. The 10-hectare area had a total of 42 mosaics of different development stages with irregular shapes and variable areas that had been separated. The initial development stage with 18 mosaics had the most and the optimal development stage with 11 mosaics had the least frequency. The area of the mosaics varied from 292 to 5145 square meters. In total, in the investigated stands, the initial stage had the highest surface and the decay stage had the lowest surface in the studied area. The initial and decay development stages accounted for the highest and lowest number of stands dendity with an average of 427 and 212 stems per hectare, respectively. The average basal area was measured as 38.75, 42.26, and 37.63 square meters per hectare in the initial, optimal, and decay development stages, respectively. The mean distance to the nearest neighbor’s index in the mosaics of the initial, optimal and decay development stages, was obtained 4.39, 4.96 and 5.76 meters, respectively. The value of Clark and Evans index was less than one in all three development stages, which indicates that the trees in all mosaics have a cluster distribution pattern. The value of the uniform angle index was calculated as 0.5 and more than 0.5 in all stages, which indicates the cluster distribution pattern of trees. The mean mingling index in the mosaics of initial, optimal and decay development stages, was obtained as 0.31, 0.27 and 0.18, respectively. Also, the mean diameter differentiation index was calculated at 0.43, 0.37 and 0.43 in the initial, optimal and decay stages, respectively. The mean height differentiation index was 0.31, 0.28 and 0.33 in the initial, optimal and decay stages, respectively, which indicates the low to medium height difference of the neighboring trees.

According to the management activities in the studied beech stands, the results of the quantification of the stand structure according to the mosaics of different development stages can be used as a guide and template for the management of other similar forest stands. Also, the characteristics and functions used in this research can be used by forest managers as indicators to measure the interventions made (like tending and marking) as well as to monitor the development stages in these stands over time. The structural diversity of uneven-aged managed forests is different among different development stages. Therefore, in order to understand how management activities, affect the short-term structural dynamics in beech forests, similar researches should be conducted in five to 10-year time series in the investigated stands. Also, to get better results, these studies should be done over time and by monitoring a fixed stand.

The importance of canopy gaps in the natural forests as a part of the development processes of the stand is not hidden for ecologists. According to the gap size, different changes will be made in the microclimate of the region, which will ultimately cause the preservation and dynamics of the structure of these stands. In close to nature silviculture, while recognizing natural disturbance regimes, efforts are made to use them as a model in sustainable forest management. The purpose of applying management based on imitation is to preserve, sustain and promote species diversity. Mimicking natural disturbances has shown different effects in managed forests. In some cases, more suitable conditions have been created for the growth of seedlings and the increase of species diversity. But in some cases, management actions were either ineffective or caused negative effects. Therefore, optimal management strategies should be based on a deep assessment of forest stands, which will provide useful data in this research.

In this research, in order to determine the possible changes due to the implementation of management, the indices of diversity of herbaceous species in the gaps of a single-selection managed and a control (non-managed) beech forest were compared in district one of Livan and Banafshtape forestry projects in Golestan province. For this purpose, after identifying and measuring the surface of all gaps, in each forest, they were classified into three groups: small (less than 200 m2), medium (200 to 500 m2) and large (more than 500 m2) and Three replicates from each group were randomly analyzed. The type and percentage of cover of all herbaceous plant species were recorded in five sample plots (one in the center and the others in the four main geographical directions of each gap). Harvesting of herbaceous species of the forest floor was done using the modified Braun-Blanquet scale. To evaluate the richness of plant species in the studied habitats, the number of plant species in each sample plot was used. Biodiversity was investigated and compared in the surveyed plots using Simpson and Shannon-Weiner diversity indices and for uniformity, Paylo's evenness index was used. The comparison of the average indices between the two compartments was done using independent t and Mann-Whitney tests, and in the gaps with different sizes, Tukey and Kruskal-Wallis tests were performed. The cluster analysis method was used to group the gaps with different sizes.

In this research, 25 herbaceous species were identified in the two investigated areas. 17 and 21 herbaceous species were identified in the gaps of the managed and unmanaged plots, respectively. Some herbaceous species were present in only one of the gap size classes, but others were identified in all three gap size classes. The results showed that there is not a significant difference between the indicators of richness (7.2±0.7 vs. 8.3±0.6), evenness (0.6±0.05 vs. 0.5±0.04), Shannon (1.1±0.1 vs. 1.1±0.09) and Simpson (0.5±0.06 vs. 0.5±0.05) between the managed and unmanaged compartments, respectively. Also, the cluster analysis showed that in terms of herbaceous cover, the gaps of the managed area cannot be separated from the unmanaged area. It is interesting to note that the species richness in the managed stand with small gap size (less than 500 m2) was significantly lower than other gaps in this stand. There was no significant difference between the other investigated indicators between the different sizes of the gaps in the managed and unmanaged compartments.

The harvesting of forest trees in the form of management can change the environmental conditions such as light and temperature in the created microclimate by creating gaps that are larger or smaller than the natural size and thus cause a change in the diversity of plant species. Although the results of some researchers showed that forest management can increase the diversity of tree species compared to unmanaged forests, but in the upcoming research, the management based on the single selection method after a period of 10 years had a significant effect on the composition and there was no diversity of herbaceous cover in the created gaps. Of course, it is necessary to remember that the type of forest management can affect biodiversity on a regional scale without causing a change on a local scale. Also, the effect of forest management on plant diversity depends on biotic and abiotic conditions and forest management approaches. The results of some studies have shown that the abundance of herbaceous species in the forest floor depends on the abundance of tree species. Therefore, in a pure forest where the number of tree species is less than in a mixed forest, the low abundance of floor covering species is not far from expected. In any case, the accurate evaluation of the effects of applied management requires more studies of the floristic and soil characteristics of the gaps in different periods of time after the implementation of cuttings.

Golestan province, located in the northern part of Iran, covers an area of 20,367 square kilometers, accounting for 1.3% of the country's total area. Unfortunately, the natural resources of Golestan province have been under threat in recent decades due to deforestation, excessive livestock grazing, and other human activities. As a result, the province faces significant challenges in this regard. The considerable depletion of natural resources, coupled with environmental crises such as floods and droughts, highlights the need for a detailed investigation and research into the management state of natural resources in the province. This research aims to improve the situation by addressing and resolving the existing problems, ultimately enhancing the management of natural resources in Golestan province. The present study seeks to evaluate the model of good governance as a novel theoretical approach in the field of natural resource management. Specifically, the research aims to assess the current state of natural resource management in the eastern regions of Golestan province and its compliance with, as well as proximity to, the criteria of good governance.

In the current research, the natural resources departments in the eastern region of Golestan province were selected as the level of analysis. This includes the cities of Ramyan, Minodasht, Kalaleh, Galikesh, Maraveh Tappeh, and Gonbad kavous. The focus of the analysis was on the users and beneficiaries of natural resources. Cochran's formula was employed to determine the required sample size. Based on this calculation, the estimated sample size was determined to be 189 samples. After receiving and reviewing the questionnaires, a total of 177 valid questionnaires were accepted for statistical analysis. Next, the prepared questionnaires were distributed among the users and beneficiaries of natural resources. Due to difficulties in accessing the target community, the research utilized available samples to answer the questions and complete the questionnaires. The research employed the one-sample t-test to analyze the governance indicators in natural resource management and one-way analysis of variance (ANOVA) was conducted to compare the level of good governance in natural resource management among the surveyed cities.

The obtained results revealed that among the seven indicators used to assess good governance, four indicators, namely participation, responsibility, efficiency and effectiveness, and the consensus index, received higher scores compared to the theoretical average, while the remaining indicators scored lower. Specifically, the participation and consensus indicators achieved the highest scores of 3.3838 and 3.7333, respectively, while the rule of law and justice index and the transparency index obtained the lowest scores, averaging 2.2551 and 2.2570, respectively. When comparing the governance scores across different departments, it was found that the cities of Ramyan and Maraveh Tappeh exhibited the best and worst good governance conditions, with average scores of 3.2 and 2.12, respectively. The results of Lon's test demonstrated a significant difference in the variance of good governance among the cities. The overall average of the good governance index for natural resources in this research was determined to be 2.8884, which falls below the theoretical average and indicates relatively poor governance of natural resources in the research area. The one-sample t-test confirmed a significant difference between the good governance of natural resources and the average level of the objects under investigation. Additionally, the results revealed a significant difference between the indexes of good governance of natural resources in Maraveh Tappeh city compared to other surveyed cities. In other words, Maraveh Tappeh city displayed a distinct and weaker governance situation compared to the other cities. Examining the indicators of good governance in Maraveh Tappeh city revealed that, from the users' perspective, the indicators of transparency and law scored the lowest among the seven indicators, with scores of 1.458 and 1.647, respectively. This suggests that compliance with laws is not in a favorable state according to the users of natural resources in Maraveh Tappeh city.

According to the results obtained from this research, as well as the importance of governing natural resources, particularly through collaborative activities, involving users in the planning and formulation of natural resource plans and projects, and utilizing their knowledge, are crucial. Local users, in addition to being members of natural resource cooperatives, can play a significant role in achieving good governance of natural resources. Based on the results and findings, it is suggested that the areas under research focus more on improving the indicators of accountability, the rule of law and justice, and the transparency index, as these indicators are positioned lower compared to others. In order to achieve this, conducting public meetings to present reports from natural resource managers can be an effective approach.

In order to properly manage the forest, we need tools that can be used to study the changes in the forest structure. In this research, the structure of degraded oak forests of Piranshahr and Sardasht in West Azerbaijan province were investigated. Characteristics of the stand were investigated in two one-hectare sample plot with dimensions of 100 x 100 meters in two different forest types, including Darsarvin Sardasht (30% canopy cover, coppice with standard) and Piranshahr Pardanan (90% canopy cover and all of trees were of coppice). Using 100% inventory and a set of indices based on the nearest neighbor, three characteristics of location, mixture and dimensions of trees were investigated.

The investigation of the structure was done by using the indices of density, diameter, height, basal area and trees location. As well as the indices based on the nearest neighbor in two sample plots were used. The structural variables of all the trees in the sample plot were measured separately for coppice and standard trees. The characteristics of the species, spatial coordinates, diameter at the height of 0.5 meters of the trunk, and height of all trees were measured. Three criteria of species density, basal area and canopy cover were also used for forest typology. To describe and quantify the structural features of forest stands in this research, indices based on the nearest neighbor were used. For this purpose, distance to neighbors, uniform angle, Clark and Evans, Mingling, DBH differentiation and CC differentiation were used. The calculations related to the structural characteristics of the examined stands were done using SPSS version 20 software and the calculations related to the structural indices were done using the Crancod software set (ver 1.3).

The Clarke and Evans index with values of 0.82 and 0.94 for Darsarvin and Pardanan, and uniform angle with values of 0.56 and 0.52, respectively, showed a cluster distribution pattern and random species distribution pattern in both stands. Mingling index shows that there is more mixture of neighboring trees in Pardanan (0.65) than in Darsarvin (0.38). The diameter difference index shows a greater difference in the half-meter trunk diameter of Pardanan (0.55) compared to Darsarvin (0.46). But the canopy differentiation index shows a greater difference in the canopy cover of Darsarvin (0.58) than in Pardanan stand (0.53). The results of the combined diversity index showed that the structural diversity in Pardanan (0.41) is higher than Darsarvin (0.36). This index shows that there is a low level of combined spatial, species and dimensional diversity in the two stands. Results are consistent with the situation of the two regions that are affected by destructive factors and limited regeneration. These results can be used for comparing structural characteristics of forests and determining the impact of human intervention.

The results of the composite diversity index showed that there is a low level of spatial, species and dimensional composite diversity in the two forest stands, and these results are consistent with the influence of destructive factors as well as the limitation of regeneration. Considering the difference in the stands in the two sample plots in this investigation, the results of these indices can be used as a basis for comparison with other similar forests and determining the amount of deviations caused by natural processes and human interventions. Also, it seems necessary to achieve a suitable management model and Silviculture practices in the forests of this region and determine the structure and planning based on the current situation using these indicators.

Sustainable nature tourism development in each area requires a comprehensive knowledge and understanding of economic, social, and cultural issues and factors. Today, on a global scale, it has been accepted that nature tourism should be related to ecology, conservation from the environment, and long-term appropriate use of nature with minimal change in the balance of the environment, it should be natural and harmful. When travel becomes one of the indicators of tourists' satisfaction, the fulfillment of tourists' goals and desire for travel will increase the number of tourists who visit these areas frequently. To induce a sense of closeness to the charms of nature and native communities, and primarily this causes them to be attracted to these areas. In this regard, the Khamir and Qeshm mangrove forests are one of the natural and valuable ecosystems that have attracted the attention of planners and visitors as the main destinations for nature tourism development. Nature tourism in these habitats has been expanded as leisure activities of tourists in nature and based on purposeful trips with cultural and spiritual visits and impressions of natural attractions and enjoyment of various phenomena in the area. Due to the increasing population growth and the high demand of visitors to the development of nature tourism activities in virgin and coastal ecosystems, as well as the lack of proper planning for the development of sustainable nature tourism in the Khamir and Qeshm mangrove forests habitats led to this research. To further protect these habitats, the factors affecting the development of sustainable nature tourism should be identified and investigated from the view of tourists who travel to this area for various purposes.

The research method is descriptive-analytical, and the required information was collected through documentation, survey, and completing the questionnaire. The statistical population of the research are tourists and nature walkers who travel to the Khamir and Qeshm mangrove forests to spend their free time and visit the area. The sample size of tourists was calculated using Cochran's formula and with a confidence factor of 90% for questioning. In this regard, 100 questionnaires were randomly distributed among tourists. The results were analyzed according to the questionnaires measured by the Likert scale method, using descriptive and inferential statistical tests in SPSS software. First, the normality of the data was checked using the Kolmograph-Smirnov test, and considering that the data were non-normal, thus, using non-parametric tests (Mann-Whitney, Kruskal-Wallis, goodness of fit, and Independence), and the inferential factor analysis.

The results showed that there is no correlation and significant relationship between gender, age, and education with the number of visits to tourist attractions in the area. While a direct and significant relationship was observed between the income level of tourists and the number of times they visited. Also, visitors' knowledge of the destination can be effective in visiting in nature tourism. The results of the independence test also indicate that one of the reasons for not visiting or the low number of visits to mangrove forests Khamir and Qeshm is the insufficient knowledge and low level of awareness among tourists of the natural attractions of this area. Therefore, there is a direct and significant relationship between these two factors, and lack of recognition of the natural capabilities of the region is also effective in the visit of tourists. In addition, the analysis of the goals and desire of tourists to visit the Khmir and Qeshm mangrove forests showed that the highest factor load obtained is related to the aesthetic aspects and diverse perspectives in the area. In general, the main goal of tourists visiting these habitats is to take advantage of the natural attractions and pristine and beautiful landscapes of the area.

In the development of nature tourism, one of the most important factors is the demand of tourists and nature walkers to travel and their goals of visiting the destination. Awareness of this issue can lead to proper planning to protect natural resources and also obtain the satisfaction of tourists from traveling to these natural destinations. According to the results obtained, according to the tourist's viewpoint, the main factor in the development of nature tourism in the Khamir and Qeshm mangrove forests is the natural attractions and landscapes in this area, whose nature tourism capabilities have led to an increase in the demand and desire of tourists to visit this area. Therefore, considering that the investigated area is one of the areas under environmental protection with high species richness and valuable biological reserves, the development of nature tourism should be carried out within the framework of the principles of sustainability and under the power and capacity of the area, as well as the environmental requirements in it to be observed. In this regard, with proper planning and a comprehensive tourism plan, it is possible to develop sustainable nature tourism and increase the economic income of the area.

Classification of forest sites is one of the most basic tasks for optimal forest management, which has practical and long-term concepts, such as regulating the structure of forests, increasing forest productivity, selecting fast-growing species suitable for afforestation, afforestation. The most productive methods are increasing the yield of wood to facilitate the relationship between supply and demand, revitalizing forests, increasing access to forest resources, and also fulfilling the ecological function of forests. In recent years, the use of different factors to classify habitats has become more and more widespread. This research aims to investigate the changes of the most important soil characteristics in beech habitats in Nav-e-Islam region.

This study was carried out in the series 3 Nav Asalem and in parcels 318, 320, 336 and 350. The desired parcels are located at two heights of 1100 and 1700. Parcel 320 was considered as a control parcel. In order to investigate and determine the types of trees in the surveyed parcels, 84 square samples with dimensions of 20 x 20 meters were taken randomly with a statistical grid of 200 x 150 meters. In each sample plot, in addition to recording the characteristics of slope, aspect and height above sea level, the variables of species type, height and diameter at the breast height of all tree species were taken. Then, the tree types of the target samples were determined using two-way analysis of indicator species (TWINSPAN). To determine the location of the soil profiles, a map of the shape of the land was prepared and considering the variety of habitat features and the area of the shape of the land, 35 sample plots were determined in homogeneous units, and the profiles were dug in these units and soil samples were taken. The soils were collected from horizons A and B. After digging each profile in the desired types, the vertical section of each profile was divided into different parts based on distinguishing features such as color, texture or soil structure. The preliminary analysis of soil profiles was done in nature and then soil samples were taken from each of the separated horizons A and B and transferred to the laboratory. Then, in a dry laboratory environment, after pounding, it was passed through a 2 mm sieve and the most important characteristics of the soil were investigated. To investigate the relationship between soil characteristics and tree types, conventional comparative analysis (CCA), one-way analysis of variance (ANOVA) and Duncan's test were used.

Based on the results of the TWINSPAN analysis, the area is divided into five types of trees, including pure Fagus (F), mixed Fagus –Acer velutinum (FA), mixed Carpinus-Fagus followed Alnus (CF), mixed Fagus-Carpinus (FR1) and mixed Fagus-Acer cappadocium (FR2) was classified. Based on the ranking results, clay percentage, carbon deposition and height above sea level in A horizon have a significant correlation with the positive direction of the first region, and organic carbon, accessible phosphorus and exchangeable potassium and carbon deposition have a correlation with the negative direction of the second region. It showed significant. In B horizon, the percentage of sand and height above sea level showed a significant correlation with the positive direction of the first axis and the percentage of clay, carbon, accessible phosphorus, exchangeable potassium and carbon deposition with the negative direction of the second factor. All five tree types were affected by altitude and clay percentage in A horizon. But (F), (FR2) and (FR1) were affected by clay percentage in B horizon and carbon deposition in both horizons and potassium in A horizon. (FR1), (FR2) and (FA) were influenced by the percentage of sand in both horizons and accessible phosphorus and exchangeable potassium in both horizons. The results of analysis of variance of physical and chemical properties of soil in tree types showed that there is a significant difference between bulk density, percentage of clay, percentage of sand, base saturation, acidity, organic carbon, accessible phosphorus, exchangeable potassium and so on. There is carbon sequestration among the tree types, no significant difference was observed between the characteristics of silt percentage and porosity percentage among the tree types. Also, the results showed that there is a significant difference between the percentage of organic carbon, exchangeable phosphorus and available potassium in two soil horizons, while there is a significant difference between the differences related to appearance, percentage of clay, percentage of silt, percentage of sand, percentage There is no saturation, porosity percentage, acidity and carbon deposition in two soil horizons.

The variety of topographical conditions in the forests of northern Iran and in the studied area is the cause of many changes in plant types and soil characteristics. According to the results of this research, in the types where the beech species is more dominant, the soil conditions are not very suitable, and the mixed types of beech are settled in the habitats with more slope and lower altitude, and the shallowness of the soil and Lack of nutrients is one of the main conditions of the soils of these habitats. The presence of different types in the forest is the result of the interaction of many factors, and it has been shown in this research that soil is one of the most important environmental conditions, and its significant relationship with tree types has been confirmed. Therefore, soil can be used as a suitable indicator to distinguish forest types.

Several studies have been conducted to estimate stand volume in Hyrcanian beech forests (pure and mixed beech satnd type), so that different results have been obtained from these studies. Meta-analysis is a quantitative statistical method for combining the results of a set of separate studies that are all about a specific topic. In meta-analysis, by collecting data from many studies, the number of samples increases and therefore the range of changes becomes smaller, as a result, the importance of statistical findings increases. In meta-analysis, if there is homogeneity between the articles used, the model with fixed effects is used, and if there is heterogeneity between different articles, the model with random effects is used to combine different articles. Therefore, in a meta-analysis, a series of researches in Hyrcanian beech forests were examined. In this research, some arguments have been made about the reason for the difference in the satnd volume in different areas of the Hyrcanian forests. This is the first meta-analysis research in the field of stand volume in Hyrcanian beech forests.

Researches related to the topic of stand volume were searched in national and international databases without time limit until the winter of 2022. In this research, after a detailed review of numerous articles, the data (mean, standard deviation and number of samples) of 18 original studies related to the stand volume variable in Hyrcanian beech forests were used. These researches were published in the International Journal of Agricultural and Biosystems Engineering, European Journal of Forest Research, and Natural Areas Journal, Iran's Forest and Poplar Research (seven researches), Wood and Forest Science and Technology Researches (three researches), Iranian Forest Ecology (three studies), Forest and Wood Products (one study) and Forest Research and Development (one study)) were published. In this research, only the estimation of stand volume (not growth of stand volume) was considered. In some cases, the required data, such as standard deviation, were not available in the published articles, so these articles were excluded from the meta-analysis process, or in few cases, they were calculated by accessing the raw data of the authors. These data had different names such as stand volume, forest stand volume, and growth stand volume in forests with different structural characteristics in these articles. Due to the significance of the Cochran Q test (P≤0.05) and values greater than 75% for the I2 statistic, the random effects model was used for meta-analysis. To find the source of heterogeneity between studies, subgroup analysis was performed based on geographical regions (province) and stand composition. The results of a meta-analysis can be shown in the form of an forest plot, which is the most general and common method of displaying effect sizes. In this research, the software Comprehensive meta-analysis ver. 3 was used.

According to the significance of the Cochran Q test and the I2 index, the average stand volume was estimated to be 386.805 sylve/h (95% confidence interval: 334.92-438.68) for Hyrcanian beech forests based on the random effect model. . The lowest and highest amounts were 252.3 and 685 sylve/h respectively in the forests of Mazandaran. Most of the research was done in different places of beech forests in Mazandaran province. The subgroup analysis based on the province (geographical regions) showed that the highest value is based on the random model in the forests of Guilan province with the amount of 424.45 sylve/h (95% confidence interval: 277.57-438.46). The lowest was estimated as 285.63 sylve/h (95% confidence interval: 167.26-404.01) based on the random model in the forests of Golestan province. The meta-analysis of standing volume in the Hyrcanian forests based on tree stand composition showed that the highest value was based on the random model for the pure type of beech at the amount of 394.272 sylve/h (95% confidence interval: 277.510-688-417). The lowest value of 147/38 sylve/h (95% confidence interval: 325.94-444.34) was obtained for mixed beech type. According to the results of this meta-analysis, the volume of stands in the Hyrcanian beech forests in the pure type of beech is 125.9 sylve/h more than in the mixed type of beech.

The average volume of stands in Hyrcanian beech forests was estimated at about 386 sylve/h. The highest amount in the forests of Guilan is about 424 sylve/h. The highest amount is 394 sylve/h for the pure type of beech. So, in management plans to maintain the stability and proper tolerance of the stand, it is recommended to keep the volume of the stand at the average level. Estimating the average value of structural characteristics on a large scale provides quantitative information on the structural condition of forests to adopt a suitable and realistic policy.