Extended Abstract Background: The soil seed bank plays a vital role in maintaining the ecological and genetic diversity of plant communities. Following ecosystem disturbances, it serves as a reservoir for vegetation reestablishment. Numerous environmental and anthropogenic factors influence the density, diversity, viability, quantity, and composition of the soil seed bank. Studying the soil seed bank enables comparisons with aboveground vegetation, offering valuable insights for plant community management. Livestock movement through forested areas induces physical, chemical, and biological alterations due to trampling. Among these, biological changes—particularly in seed germination and diversity—are significant. Grazing compacts the soil and reduces its water infiltration capacity, thereby impeding seed germination. A review of existing literature reveals limited research in Iran on soil seed banks along livestock traffic routes in forests. Most studies have focused on pastures and forests under grazing and enclosure treatments, post-fire disturbances, and the relationship between seed banks and surface vegetation, as well as land-use impacts. This study aims to assess the diversity and germination potential of soil seed banks along a permanent livestock movement corridor. The findings can inform ecological restoration strategies to enhance the self-recovery capacity of these disturbed routes in the Zagros forests. Methods: The research was conducted in the Zagros forests, within the Delfan district of Lorestan Province. A livestock traffic route exceeding 4 km was identified through field surveys. Soil sampling followed a randomized controlled design. Along the route, 20 one-square-meter plots were established at 100-meter intervals, starting from a random point. From each plot, soil samples were collected at two depths: 0–5 cm and 5–10 cm. A parallel set of 20 plots was established in adjacent forest areas, located at least 100 meters from the route’s centerline, with identical sampling procedures. The greenhouse germination method was employed to evaluate the soil seed bank. Samples were cultivated in sterilized sand beds (10×40 cm), and germinated seedlings were counted, identified, and removed at 12-day intervals. After 2 weeks, trays underwent a drought treatment, followed by irrigation and further monitoring until germination ceased. Plant identification was conducted using the Flora of Iran. Seed density was calculated per unit area, and species diversity was assessed using Shannon-Wiener and Simpson indices. Statistical comparisons between the livestock route and forest plots were performed using unpaired t-tests. Results: A total of 49 plant species from 17 families were identified, comprising one tree species, two shrubs, five annual herbs, and 41 perennials. Of these, eight species were exclusive to the forest, two to the livestock route, and 39 were common to both. Life-form analysis revealed hemicryptophytes as the dominant group in both areas—29.7% in the forest, and 37.0% along the livestock route. Geophytes had the lowest representation: 4.0% in the forest and 2.5% on the route. Livestock movement increased hemicryptophyte prevalence while reducing other life forms. Unpaired t-tests indicated a statistically significant difference in seed density between the two depths (0–5 cm and 5–10 cm) and between the forest and livestock route at the 99% confidence level. Biodiversity indices also differed significantly: the Simpson index was higher in the forest (0.90) than on the route (0.82), and the Shannon-Wiener index followed a similar trend (0.86 vs. 0.79). Conclusion: The study demonstrates that hemicryptophytes dominate both forest and livestock traffic areas. However, biodiversity indices and seed density are significantly lower along livestock routes, indicating ecological degradation. These findings underscore the need for targeted restoration efforts to rehabilitate disturbed forest corridors. Understanding soil seed bank dynamics in modified ecosystems is essential for effective management and ecological recovery planning.

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.

IntroductionSoil erosion is a natural process that is intensified by human activities. Experts of natural resources consider soil erosion as a phenomenon that has caused the destruction of civilizations. Preventing erosion and actually reducing its damages to the natural level of soil losses depends on choosing appropriate strategies for soil protection. Preventing erosion and actually reducing its damages to the natural level of soil losses depends on choosing appropriate strategies for soil protection. Among the many methods of preventing soil erosion and increasing the stability of slopes, bio-engineering methods of protected areas have received a lot of attention due to environmental and economic issues in engineering today. Materials and MethodsIn this research, the effect of the root of Celtis caucasica and Pistacia atlantica in soil reinforcement around the Kalan Dam, 34 km southwest of Malair City, was investigated on different slopes. To carry out this study, two species of Celtis caucasica and Pistacia atlantica were investigated in three different populations in three areas with low (0-10 %), medium (10-25 %), and high slopes (25-40 %). The root samples were collected on December 15, 2021, from a depth of about 30 cm. In general, 6 individual trees were randomly selected in each area and all the characteristics of the soil were examined in 6 repetitions and the root in 10 repetitions (to test the tensile strength of the roots). The treatment used to preserve and prepare the roots includes washing and placing them in plastic bags containing a 15 % alcohol solution. Then samples with a length of about 10 cm were randomly selected and the speed of the tensile strength test was 10 mm min-1. The root was measured using a standard Instron device manufactured by the Santam factory. Considering the normality of the data, the t-test was used to compare the two species. Three harvesting areas with different slope classes, including low (Region 1), medium (Region 2), and high (Region 3) slopes. The treatment used to preserve and prepare the roots includes washing and placing them in plastic bags containing a 15 % alcohol solution. Then samples with a length of about 10 cm were randomly selected and the speed of the tensile strength test was 10 mm min-1. The root was measured using a standard Instron device manufactured by the Santam factory. Considering the normality of the data, the t-test was used to compare the two species. In three harvesting areas with different slope classes, including low (Region 1), medium (Region 2), and high (Region 3) slopes, 18 stems of Callaghan and 18 stems of P. atlantica were harvested for root Callaghan, and 18 stems of P. atlantica were harvested for root sampling. Results and DiscussionThe results showed that the root elasticity of C. caucasica is higher than P. atlantica. The relationship between the diameter and root reinforcement was different, and about C. caucasica it was negative. the highest root reinforcement is related to fine roots. The RAR (Root Area Ratio) in C. caucasica was higher on a high slope rather than a low slope. In steep slopes (Region 3) root tension of C. caucasica is higher than the area with the average slope. There was a positive correlation between PL and LL of soil in C. caucasica stand in Region 3. Finally, strengthen the soil and reduce erosion in the upper slopes. The noteworthy point is that the percentage of carbon in the soil in Region 3 is higher than in the other two regions, which is due to the negative correlation between carbon and sand in the soil. C. caucasica in high-slope lands with a lower percentage of sand causes an increase in carbon deposition and parameters of the dough limit and liquid limit of the soil. According to the results of the data, the amount of root elasticity of C. caucasica is higher than P. atlantica species. The relationship between diameter and root tension is different in the case of species. About C. caucasica it was negative and the highest root tension is related to the roots of the fine roots, but in P. atlantica, the relationship between diameter and tension is a positive power function and As the diameter increases, the amount of tension increases. The amount of root area ratio (RAR) in C. caucasica is higher on the higher slope than on the lower slope. The percentage of clay in the soil texture has a negative correlation with the amount of RAR, and root growth and distribution are less in clay soils. C. caucasica in high-slope lands with lower sand percentage increases carbon deposition and parameters of the plastic limit and liquid limit of the soil. ConclusionIt is suggested to use species that increase soil reinforcement and reduce the amount of erosion in the area of the dam in order to reduce the amount of erosion and increase the useful life. according to the results, it can be recommended that it is better to use C. caucasica in afforestation around the Kalan Dam because of its greater effect in increasing soil improvement and reducing erosion.

Leaf litter decomposition plays a key role in the nutrient cycle of forest ecosystems. However, there is not a comprehensive understanding of the non-additive decomposition effects in leaf litter mixing experiments. In this study, the dynamics of nutrients and the rate of decomposition of Iranian oak (Quercus brantii), tree of heaven (Celtis caucasica), and wild pistachio (Pistacia atlantica) were investigated in both pure and mixed stands. For this purpose, 81 single- and double-litter bags were placed in the study area and incubated for 180 days. According to the results, at the end of the incubation period, the decomposition of oak litters in combination with tree of heaven, tree of heaven in combination with wild pistachio, and wild pistachio in combination with oak showed positive results. Based on the results, the nitrogen concentration in oak mixed with tree of heaven was higher than in its pure state. But the concentration of phosphorus in its pure and combined states did not show any significant differences. In general, the findings showed the positive non-additive effects of litter on its decomposition rate. Regarding the dynamics of nutrients, these effects were considered positive only for nitrogen.

Extended Abstract Introduction and Objective: The decline of natural forests has been caused urban afforestation to acquire a particular importance with the purpose of green space development level, therefore, the selection of appropriate plant species plays a substantial role in the development and stability of urban green space. The nutrients evaluation is significant in in selection of appropriate species for planting and in a way that species can be selected and supplemented by either consumption of the whole available nutrients in habitat or with their accompanying species. Material and Methods: The present study was conducted to evaluate the high consumption nutrients (Nitrogen, Phosphorus, Calcium, Carbon, Magnesium and Potassium) in the leaves of Mulberry, Ash, Tehran Eldarica Pine and Arizona Cypress in two summer and autumn seasons in four geographical areas (Jamshidieh Park, Sorkheh Hesar Park, Vard Avard Park and Shaghayegh Park) in Tehran. Also, retranslocation of nutrients was measured in four parks and three species (Mulberry, Ash and Tehran Eldarica Pine). At the end of the growing season, the mature green leaves (80 samples) and at the end of the autumn season, the fallen leaves (60 samples) were collected at the base of the tree and packed in zippered bags with the desired specifications on them and transferred to the laboratory. The leaves were washed with sterile distilled water to remove contaminants, then dried in an oven at 70 ° C for 24 hours and then ground. Chemical analyzes were performed using standard instructions. Statistical analyzes such as general comparison of means (one-way analysis of variance) and group means (Duncan test) were performed. Results: The results of this study showed that the average nutrients in summer leaves are higher than autumn leaves. In Sorkheh Hesar, Shaghayegh and Jamshidieh parks, in summer leaves, the highest amounts of nutrients related to calcium (62.66 mg/g in Shaghayegh Park) and in Alder was recorded. While in Vard Avard Park, the highest amount of this element was observed in mulberry (68.32 mg/g). In autumn leaves, in three parks of Shaghayegh, Jamshidieh and Vard Avard, the highest concentration of nutrients related to calcium (42.66 mg/g in Shaghayegh Park) and was recorded in mulberry. While in Sorkheh Hesar Park, calcium concentration was recorded in Alder (50.66 mg/g). Regarding the percentage of nutrient retranslocation in the studied species in Sorkheh Hesar Park Magnesium (63.04%) in Alder, in Shaghayegh Park Potassium (52.58%) in Mulberry, in Jamshidieh Park Potassium (63.79%) in Tehran Eldarica pine and in Vard Avard Park calcium (41.45%) in mulberry had the highest nutrient retranslocation. Conclusion: The species studied in this study had different nutrients in their summer and autumn leaves. These species also retranslocation a different amount of each element. It is suggested that this issue be taken into consideration in the management and planning of urban forestry, and the tree species used, which are mainly the main tree species in urban forestry, should be classified based on the status of nutrients.

The effect of carbon nanotubes, calcium chloride and potassium nitrate on germination traits of Iranian Oak seed (Quercus brantii)

The dynamics of nutrients and their return to the soil through the litter is one of the most important pathways of the nutrient cycle in forest ecosystems. The aim of this study was to evaluate the dynamics of nutrients in pure beech, pure hornbeam and beech-hornbeam stands in Darabkola educational-research forest of Sari. For this purpose, in each stand, 10 sample plots with 1000m2 area were randomly established and by measuring the diameter and height of the trees, descriptive statistics of the studied stands were calculated. Then, litter traps with dimensions of 50 × 50 cm to measure the amount of litter fall per unit area and litter bags with dimensions of 20 × 20 cm (with a pore of 2 mm) with 10 replicated were installed in the studied stands for 360 days and at intervals of 60, 120, 180, 240, 300 and 360 days, the concentrations of nitrogen, carbon, phosphorus and potassium in the litter of the bags were measured. According to the results, the highest rate of litter falls with 1817 kg/ha was related to November and December in beech stands. In addition, the highest input of the studied elements was related to the pure hornbeam stand. The resultas also indicatedthe dynamics of phosphorus, potassium and carbon elements in pure and mixed stands are decreasing with a slight increase at the end of the period and increasing in the case of nitrogen and decreasing at the end of the period. The dynamics of the elements in the mixed stand showed more fluctuation than the pure stands. Also, the results of this study showed that the 200th to 300th days after litter fall is an important time range in the fundamental changes in the dynamics of litter nutrients.

Litter quality plays a key role in the decomposition process and nutrients dynamics. In most studies, it is assumed that litter has a higher rate of decomposition in its ecological site. Evidence for this theory has not yet been fully confirmed. Therefore, in order to test this theory and also to investigate the effect of litter quality on its decomposition rate in two stands of european black pine (Pinus nigra Arnold) and tree of heaven (Ailanthus altissima Mill.) leaf-litters of P. nigra Arnold and A. altissima Mill were incubated for 180 days using the litterbag method in Shahed's forest park of Malayer. The chemical quality of litter, the rate constant for decomposition, the main ecological site advantage and the effects of mixtures litter were investigated through the relevant relations. Results showed that the rate constant for decomposition of A. altissima litter (with high levels of nitrogen and calcium and low C/N ratio) was higher than P. nigra (0.09 and 0.05, respectively). Competitive status was observed in all compounds except P. nigra samples in their sites. Also, the decomposition rates of the litters had a significant positive relationship with the concentrations of nitrogen (r = 0.76, p <0.05) and phosphorus (r = 0.62, p <0.05) and had a significant negative relationship with the concentration of potassium (r = -0.74, p <0.05) and C/N ratio (r = -0.76, p <0.05). The theory of home-field advantage was confirmed about european black pine and tree of heaven in their own ecological sites. In general, the results showed that the decomposition process is affected by both litter quality and home-field advantage of leaf-litter decomposition. According to the research results, mixed afforestation of these two species was suggested in the temperate cold climates of the west of the country.

In recent years, forest control and management in accordance with biodiversity and economic and social issues and its relationship with sustainable development has received a lot of attention. The present study aims to evaluate and compare the resource stability of two forest reserves in the valley of Somaqh and Baneh Aznavaleh Malayer in Hamadan province. In this study, a combined method, including multi-criteria AHP evaluation method and sustainability indicators the guidelines of the 505th issue of the Forests and Rangelands Organization have been used to determine and prioritize indicators of sustainable forest management at the local level. Biodiversity, with the lowest score in both reserves including legal measures and organizational structure, economic and social functions, forest production functions, forest resources, conservation functions with the lowest score have the greatest impact on the instability of two forest reserves respectively. Somaqh Valley forest reserve with a final weight of 0.571 compared to Baneh Aznavleh forest reserve with a final weight of 0.428 has more relative stability which is due to better biodiversity and species richness. So that the Somaqh Valley Reserve with a score of 51 has moderate stability and Aznavaleh, 31 points, is in a state of instability. Biodiversity, health and well-being, conservation functions, economic and social functions of Somaqh forest reserve has better sustainability which is due to the greater differences and advantages of indicators of forest resources. Indicators show the importance of local participation in the sustainable management of both reserves. So that the lack of social acceptance is one of the most important reasons for the failure of forest rehabilitation plans and programs. The combination of AHP model technique and forest sustainability assessment indicators can be an appropriate tool for sustainable forest management. Keywords: Biodiversity, Sustainable Forest Development, Somaqh Valley, Baneh Aznavaleh Introduction The concept of sustainable forest management has three basic elements including economic, social and ecological sustainability, which has received much attention regarding biodiversity and economic and social issues and its relationship with sustainable development in recent years. Some criteria have been proposed to assess forest sustainability in which biodiversity is considered as one of the important criteria. Nowadays, the recognition of indicators is recognized as a tool to assess forest sustainability by planners and decision makers. Recent studies show that existing benchmarks and indicators are applicable nationally and internationally which can rarely be applied locally. In fact, these national indicators and criteria must be adjusted to make the right decision at the local level to be usable. Therefore, distances and uncertainties should be evaluated in order to determine local criteria and indicators, so that they can be used in relation to forest sustainability assessment at the local scale. These criteria and indicators should include all stakeholders with different economic and social demands and needs and be effective, useful and efficient in sustainable forest management decisions. The present study aims to evaluate and compare the resource sustainability of two forest reserves Somaqh vally and Baneh Aznavaleh Malayer in Hamadan using a combined method to determine and prioritize sustainable forest management indicators at the local level using AHP multi-criteria evaluation method and indicators. Sustainability is the guideline of the 505th publication of the Forests and Rangelands Organization of the country. Materials and Methods In this study, a combined approach including AHP hierarchical analysis process method and guidelines of 505 Journal of Rangeland Forests Organization has been used to determine and prioritize criteria and indicators of sustainability at the local level forest reserves of Baneh Aznavaleh and Somaqh vally of Malayer in Hamadan. At first, the viewpoints of the two main groups, including local stakeholders and the second group of academics and research centers were applied to determine local criteria and indicators. Since the views of local stakeholders do not express all the challenges of sustainable management of the two repositories, we have used the second group to complete the process of determining and prioritizing the criteria. Then, the weight and absolute weight are calculated based on AHP method. In the next step, the forest stability score is calculated and compared with the absolute weight according to the instructions of the 505th publication of the Forests and Rangelands Organization. The stability of the two reserves has been evaluated. Results and Discussion The evaluation of the criteria showed that the prioritization of the criteria based on weight, from the highest to the lowest, includes biodiversity, socio-economic issues, production roles, health and survival, legal frameworks, erosion, quality and extent, respectively. The role and impact of biodiversity with the highest weight is the most important indicator in the sustainability of both reserves. In general, the study of relative weights for each reserve, total relative weights, final weight of each reserves in terms of sustainability showed the Somaqh forest reserve are more preferred than Aznavaleh reserve in terms of biodiversity, socio-economic criteria, legal frameworks, policies Organizational, production roles and quality .The results show that the Somaqh Valley deposit with a final weight of 0.71479764 is in a better condition in terms of stability than the Baneh Aznavaleh reserves with a final weight of 0.480654343. The results of total relative weights show that after biodiversity, economic and social functions, forest production functions, forest resources range, and conservation functions have the greatest impact on the instability of both forest reserves, respectively. Conclusion Studies show that the final score of stability of Somaqh forest is 51 and Baneh Aznavaleh forest is 31, which based on the qualitative determination of sustainability indicates the existence of instability in Aznavaleh reserve and moderate stability in Somaqh valley. Surveys show that the importance of biodiversity is very important in forest sustainability leading to instability due to low scores in both reserves. Field observations show that biodiversity, health and vitality, extent and production functions and conservation are the most important indicators that are relatively better in the Somaqh forest. However, studies show that the forests of the region are not able to produce industrial wood due to special ecological conditions. Their main function is a supportive and protective role. These indicators show the importance of local people in the sustainable management of both reserves. The lack of social acceptance is one of the most important reasons for the failure of plans and programs for sustainable forest restoration and development.

The role of trees in reducing the amount of heavy metals in the air and thus reducing the environmental risks cannot be denied. In the present study, distribution of cadmium, nickel, lead and zinc metals was investigated in leaf and skin of Plane tree, Ash and Eldarica pine in urban parks of Hamadan. For this purpose, in the different parks of Hamadan, samples were taken from the skin and leaves of the trees. After transferring the samples to the laboratory and digesting them, the concentration of metals was measured by atomic absorption. Comparison of the concentration of heavy metals in the leaves and the skin of the tree species showed that the Plane trees have a higher ability to absorb of heavy metals than the Ash and Eldarica pine trees. The zinc concentration in the skin and the leaves of the trees was higher than the concentrations of other elements. Comparison of the concentrations of the elements in the skin and the leaves of the trees with global standards showed that the concentration of cadmium in the skin and leaves of trees was higher than the standard limit and the concentration of nickel in the skin of the two Plane tree and Ash species was higher than the standard limit Which indicates the pollution of the urban environment. Correlation between the concentration of heavy elements in the skin and the leaves of the trees showed that there was a significant positive correlation between cadmium concentrations in leaves and skin of Plane tree and Eldarica pine trees (P <0.05). In general, the comparison of heavy metal concentrations in the leaf and skin of the tree species showed that Plant tree and Ash were very effective in absorbing heavy metals from their surroundings than Eldarica pine.

Habitat change leads to differences in the rate of decomposition and nutrient dynamics of leaflitters, which has many effects on the controlling factors of the decomposition process. In the present study, the rate of decomposition and nutrient dynamics of Norway spruce were evaluated for days in the two forestation sites in the natural and foreign habitats, Stråsan and Lajim. Nutrients such as nitrogen, phosphorus, potassium, calcium, magnesium, manganese and lignin, as well as Limit value, constant coefficient of decomposition and production capacity of humus were investigated using standard methods in both habitats. Nutrient and lignin concentrations were measured individually in each country using the same measurement method. The results showed that the initial quality of needles, except for calcium and manganese, in Lajim habitat (the concentrations of nutrients in nitrogen, phosphorus, potassium and magnesium were , , , and mg/g) was better than Stråsan (the concentrations of calcium and manganese were and mg/g). The dynamics pattern of nutrients in two habitats was similar during the study period, but in day, there were significant differences ( p < ) in the concentrations of manganese and phosphorus. The remaining weight in two habitats at the end of the period did not show any significant difference (Lajim and Stråsan habitats were and respectively). The constant coefficient of decomposition and production capacity of humus in Lajim habitat was higher (respectively, per day and fractions) than Stråsan habitat (respectively, per day and fractions). Based on the stepwise regression, in the Lajim habitat the concentrations of phosphorus and manganese and in the Stråsan the concentrations of lignin, magnesium and calcium were the only variables which explained mass loss variation. In general, the results of this study showed that Norway spruce in Lajim habitat was successful in the view point of the decomposition and nutrient dynamism and in the compared to its natural habitat, and could be used in the Hyrcanian mountain forest for reforestation projects.

The aim of this study was to determine the spatial pattern and intra-specific interactions of Anagyris foetida shrubs in its unique habitat in the Zagros forests. For this purpose, 1-ha sample plot which is covered by relatively pure Anagyris foetida was established. The spatial location of each individual was calculated using azimuth and distance measurement. Furthermore, the biometric characteristics of the individuals were measured. Then, the spatial pattern of the shrubs were determined using the nearest-neighbor and pair correlation functions. In addition, the spatial correlation of shrubs size was determined using Mark correlation and Mark variogram functions. The measurement of biometric characteristics of shrubs showed that the mean collar diameter, height, crown area and number of sprouts were 5.15cm, 2.36m, 5.6m2 and 12.59, respectively. The density was 231 shrubs per hectare. Based on the results of the spatial pattern analysis, the shrubs were aggregated at small spatial scales and tend to follow random distribution pattern at larger distances although the results of the pair correlation function (g) showed an aggregation at distances 13-17m. The results of the Mark correlation and Mark variogram functions showed no spatial correlation among shrubs for the biometrics characteristics implying that the shrubs arrangement by their size follows complete randomness. It was concluded that although there is a positive interaction (aggregation) in small spatial scales, no specific spatial structure was observed. The size of the shrubs was not spatially correlated and the neighboring shrubs were randomly distributed with different sizes.

Livestock are a threat to forest regeneration. Moreover, soil quality and fertility is degraded under their hooves. Livestock grazing in natural forests of the Zagros Mountains, in western Iran, create or maintain temporal or permanent transit paths through valuable oak stands. We surveyed the physical, chemical, and biological characteristics of the soils on a permanent path that has been used for livestock daily transit for 80 years. We sampled soils on a 1 km transect along this path, using a random systematic design. Moreover, soils were sampled along another transect inside of the adjacent, undisturbed oak stand. There was little litter on the path used by the cattle, and the bulk density of the soil was 35% higher in the intact soils of the forest-stand, proving soil compaction under livestock hooves. Despite these differences, pH, EC values and the concentration of Na didn't differ between the two transects. Percentages of N, P, K, and organic matter, however, were higher in the intact soils of the forest-stand. On the other hand, the activity of urease, acid phosphatase, and alkaline phosphatase was more than three-fold higher in the forest-stand. Soil salinity didn't change after 80 years, but soil nutrients, organic matter, and enzyme activities dramatically decreased. Phosphorus concentration and soil enzyme activities are sensitive to soil compaction by livestock and are good indicators of livestock trampling.

In this study, biotechnical characteristics of the root system of Quercus brantii and Crataegus aronia, were studied in Zagros forests, the west of Iran. For each species, a number of eight individual trees were selected and 73 root samples were tested for measuring tensile strength using Instron Universal Testing Machine. Results showed a negative relationship between the diameter and tensile strength. The minimum and maximum tensile strength values in the diameter range of 0.13-2.93 for Q. brantii were 15.01 and 116.08 MPa and in the diameter range of 0.32-2.97 cm for C. aronia were 12.98 and 83.10 MPa, respectively. The parameters for soil cohesion and angle of internal friction of soil particles for soil samples of each individual trees were Seite 284 Tahereh Heidarian, Farhad Ghasemi Aghbash, Iman Pazhouhan measured using direct shear test apparatus after transporting samples to the laboratory. Calculation of soil reinforcement of the two species is based on a modified Mohr-Coulomb concept (Wu model) and on measured data of tensile strength and root area ratio (RAR). The maximum values of soil shear strength, considering the root cohesion effect of Q. brantii and C. aronia, have been estimated with 100.40 MPa and 98.28 MPa respectively. The results showed that the soil shear strength of Q. brantii is higher than C. aronia. The results confirm the effect of forest on slope stability and the findings of our study can be used in reinforced soils and lower the risk of landslides.

The aim of this study was to evaluate the traffic-related effects on morphological and anatomical traits of Fraxinus rotundifolia and Morus alba along the Malayer-Hamedan road. In the study area, populations of two species of F. rotundifolia (30 individual trees) and M. alba (30 individual trees) were selected for sampling. The results showed that the leaf and stomata dimensions at distances near to the roadside were significantly lower compared to longer distances from the road. For F. rotundifolia, the number of veins showed the lowest plasticity, while in case of M. alba, the stomata length (P = 0.52) and the number of veins (P = 0.54) showed the lowest plasticity related to the environmental conditions. Results of discriminant analysis for population grouping for the two species of F. rotundifolia and M. alba confirmed the accuracy of grouping 74.8% and 79.5%, respectively. In case of trees that were farther away from the road, guard and epidermal cells were located at the same level. We found that the leaf stomata in M. alba were closed more than in F. rotundifolia at the same distance. Totally, the results of this research show that the air pollution stress impacted the tree morphological traits. From the two species, F. rotundifolia was more resistant in terms of pollution stress.

The return of nutrients through leaf litter is one of the most important ways of nutrient cycling and soil fertility conservation in forest ecosystems. The dynamics of nutrients and litter decomposition in the forest have great influence on the availability of soil nutrients.The present study was conducted with the aim of evaluating the nutrient dynamics and leaf litter decomposition in Persian oak (Quercus brantii Lindl.) leaf litter using litterbag method for 360 days in Chahar Zabar forests of Kermanshah province. In this study, litterbags (30×20 Cm and 2 mm mesh) were sampled with five replicates at intervals of 60, 120, 180, 240 and 360 days and the following factors were measured: decomposition rates, chemical components of leaf litters such as nitrogen, carbon, phosphorus, potassium, calcium, magnesium and AUR (Klason lignin). The results showed that in the first year, the mass loss of leaf litter was 45.9%. The nitrogen concentration was 12.22 mg.g-1 which indicates that Iranian oak is a tree with moderate soil modification. The concentration of nutrients was Ca (48.58 ± 0.37 mg.g-1) > N (25.16 ± 0.93 mg.g-1) > P (11.76 ± 0.36 mg.g-1) > Mg (2.73 ± 0.15 mg.g-1) > K (2.55 ± 0.27 mg.g-1). The results of nitrogen release and degradation of lignin showed that nitrogen release had a negative trend up to 180 days and then it was positive until the end of the period. Based on the stepwise regression the C/P and N were the only variables entered into the model which explained 85.8% of mass loss var­iation. In general, the results of this study showed that Iranian oak modified the soil nitrogen intermediately and has no high potential for humus production.

In this study, biotechnical characteristics of the root system of Quercus brantii and Crataegus aronia, were studied in Zagros forests, the west of Iran. For each species, a number of eight individual trees were selected and 73 root samples were tested for measuring tensile strength using Instron Universal Testing Machine. Results showed a negative relationship between the diameter and tensile strength. The minimum and maximum tensile strength values in the diameter range of 0.13-2.93 for Q. brantii were 15.01 and 116.08 MPa and in the diameter range of 0.32-2.97 cm for C. aronia were 12.98 and 83.10 MPa, respectively. The parameters for soil cohesion and angle of internal friction of soil particles for soil samples of each individual trees were measured using direct shear test apparatus after transporting samples to the laboratory. Calculation of soil reinforcement of the two species is based on a modified Mohr-Coulomb concept (Wu model) and on measured data of tensile strength and root area ratio (RAR). The maximum values of soil shear strength, considering the root cohesion effect of Q. brantii and C aronia, have been estimated with 100.40 MPa and 98.28 MPa respectively. The results showed that the soil shear strength of Q. brantii is higher than C. aronia.The results confirm the effect of forest on slope stability and the findings of our study can be used in reinforced soils and lower the risk of landslides.