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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.

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.

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.

The deterrence system has developed with the evolution of the international system and has experienced new forms. Facing the unstable and unpredictable challenges of the future, along with asymmetric threats in a nonlinear mechanism, is required to design a new analytical apparatus of deterrence and its conceptual and theoretical reconstruction. It forms the main purpose of the present article. In this regard, the fundamental question arises as to how in this model of the emerging international system, deterrence can be reconstructed conceptually and theoretically? The author intends to reconstruct it by using the method of deductive inference and focusing on theories of complexity and chaos, especially its basic principles such as the networked structure of the system, nonlinearity, sensitive dependence, and cascading failure. This study focuses on the dynamics of power and the mechanisms that turn it into a threat through nonlinear logic and its mechanisms and the principles emphasized by the theory of complexity and chaos. The author introduces nonlinear network deterrence to the field of strategic studies as an innovative and new concept. This pattern is a start point of the sixth wave of deterrence in International Relations. It will provide a new model for designing Iran's deterrence.

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.

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.

The survey of the ecological and m orphological characteristics of medicinal plants is one of the essential requirements for multipurpose use of rangelands. Accordingly, the ecological and morphological characteristics of Ephedra procera were investigated in the mountain rangelands of Urmia. For this end, regarding to the physical and vegetation characteristics; three habitats representing a wide range of areas of E. procera distribution region were selected. Then, the data inventory was conducted within 30 two square meters plots established on transects along 100-meter with distances of 10 meters apart and the morphological characteristics and amount of forage production were measured. To study the relation between distribution of vegetation and soil characteristics, soil samples were taken with three replications along transects. The results showed that the morphological characteristics of Ephedra and soil physical and chemical properties in study sites; are significantly different among the sites. Analysis of variance linear regression equation between forage production of Ephedra with morphological characteristics indicates a significant relationship between forage production and number of plant shoots. The results of studying the relationships vegetation distribution with environmental factors showed that the influence of environmental variables on vegetation is significant which accordingly the factors such as slope, temperature, aspect, porosity, sand, elevation from sea level, percent of gravel, bulk density and electrical conductivity are of the most important factors affecting the distribution of Ephedra species. The results can be used in planning the protection and restoration practices of Ephedra in natural habitats.

A study was conducted to investigate the effective factors in the formation of the forest structure across the Aras Riparian Zone in northwestern Iran. To this aim, the study area was divided into 5 units based on the vegetation status (natural, artificial), destruction rate of riparian zone and topography. The silvicultural (e.g. density, average diameter, average height, growth form, canopy cover and quality of trees), ecological and socioeconomic ecological, socioeconomic parameters were studied in each unit.The silvicultural parameterswere surveyedwithin a number of 20 sample plots each encompassing 10×10 m which were selected by randomized systematic design. The results showed that species density was the only factor showing a significant difference (p

Plant litter decomposition plays an important role in forest soil fertility due to nutrient cycling and soil organic matter formation. Litter decomposition, results in return of leaves nutrient to soil and supply of necessary elements for plant growth. In fact, nutrient availability is highly related to litter nutrient dynamic in soil. In this study the nutrient dynamic of Norway spruce litter was investigated in both pure and mixed condition to determine whether its nutrient dynamic is affected by its composition with broad-leaved litters or not. For this reason, Norway spruce litters were treated for 400 days at pure and mixed conditions with Beech (Fagus orientalis lipsky), Alder (Alnus subcordata C.A.Meyer) and Maple (Acer velutinum Boiss.) litters in pure Norway spruce plantation at Lajim site, using litter bag method. The results showed that the non-additive effect of litter composition on dynamic of lignin and manganese was neutral, but on dynamic of nitrogen, potassium and magnesium was positive, whereas on dynamic of calcium was negative. The finding of this study showed that litter mineralization rate of nitrogen in the three treatments of litter composition was higher than the its rate in the pure Norway spruce litter, whereas the mineralization rate of manganese was negative at the end of the study time in all the combinations, except for Norway spruce mixed with beech.

Introduction Geological background Ophiolites have played a major role in our understanding of Earth’s processes ranging from seafloor spreading, melt evolution and magma transport in oceanic spreading centers, and hydrothermal alteration and mineralization of oceanic crust to collision tectonics, mountain building processes, and orogeny. They provide the essential structural, petrological, geochemical, and geochronological evidence to document the evolutionary history of ancient continental margins and ocean basin. Ophiolites include a peridotitic mantle sequence, generally characterized by high-temperature plastic deformation and residual chemistry, and a comagmatic crustal sequence (gabbros, diabase dikes, and submarine basalts), weakly or not deformed. According to this interpretation, ophiolites were allochthonous with respect to their country rocks. They were assembled during a primary accretion stage at an oceanic spreading center, and later tectonically emplaced on a continental margin or island arc (Dilek, 2003). The indigenous dikes of pyroxenites and gabbros that were injected into a melting peridotite, or intrusive dikes of pyroxenite and gabbro that injected when the peridotite was fresh and well below its solidus, are discussed in different ophiolite papers. Pyroxenite formation and contact of gabbro and mantle peridotite are discussed in different articles (Dilek, 2003). When a gabbro intrude a fresh mantle peridotite could not significantly react with it, but if intrusion occurs during the serpentinization, the gabbro will change to rodingite. Geological setting The Naein ophiolitic melanges comprise the following rock units: mantle peridotites (harzburgite, lherzolite, dunite, with associated chromitite), gabbro, pyroxenite, sheeted and swarm dikes, massive basalts, pillow lava, plagiogranite, radiolarian chert, glaubotruncana limestone, rodingite, listvenite, and metamorphic rocks (foliated amphibolitic dike, amphibolite, skarn, banded meta-chert, and succession of schist and marble) (Davoudzadeh, 1972; Jabbari, 1997; Pirnia Naeini, 2006; Torabi, 2012; Shirdashtzadeh, 2006). In this ophiolite, the leucogabbro intrusions crosscut all other rock units. Materials and Methods Mineralogical analyses were conducted by wavelength-dispersive EPMA (JEOL JXA-8800R) at the Cooperative Centre of Kanazawa University (Japan). The analyses were performed under an accelerating voltage of 15 kV and a beam current of 15 nA. JEOL software using ZAF corrections was employed for data reduction. Natural and synthetic minerals of known composition are used as standards. The Fe3+ content in minerals was estimated by assuming mineral stoichiometry. Results In the contact zone of leucogabbros and mantle peridotites of the Naein ophiolite, wehrlite and olivine clinopyroxenite are formed. Rock-forming minerals of these wehrlites are olivine (chrysolite), clinopyroxene (diopside), Cr-spinel, serpentine, amphibole (tremolite and tremolitic hornblende), epidote and magnetite. Comparison of mineral chemistry of olivine, clinopyroxene and chromian spinel in wehrlites and mantle peridotites indicate that chemical composition of clinopyroxene and olivine in these rocks are different, but chemistry of Cr-spinels in harzburgite and wehrlite are nearly same. Discussion According to the resistance of Cr-spinel against the metamorphism and alteration, it can be concluded that the wehrlites in contact zone of gabbros and mantle peridotites are formed at the expense of harzburgite. Olivine and clinopyroxene of wehrlites are formed by serpentine metamorphism and interaction of serpentine and calcium of gabbro, respectively. Field study of the research area shows that the leucogabbro intrudes the harzburgite. This research shows that after the serpentinization of mantle harzburgite, the gabbro intrusions crosscut the serpentinized peridotites, and wehrlite and olivine clinopyroxenite formed in the contact zone. Acknowledgements The authors thank the University of Isfahan for financial support. References Dilek, Y., 2003. Ophiolite concept and the evolution of geological thought. Geological Society of America Special Paper 373, 504. Davoudzadeh, M., 1972. Geology and Petrography of the area north of Nain, Central Iran. Geological Survey of Iran, Tehran, Report 14, 92 pp. Jabbari, A., 1997. Geology and petrology of the northen Naein ophiolites. M.Sc. Thesis, University of Isfahan, Isfahan, Iran, 162 pp. (in Persian) Pirnia Naeini, T., 2006. Petrology of mantle peridotites of the Naein ophiolite. M.Sc. Thesis, University of Isfahan, Isfahan, Iran, 191 pp. (in Persian with English abstract) Torabi, G., 2012. Central Iran ophiolites. Jahad daneshgahi, Isfahan, 443 pp. (in Persian) Shirdashtzadeh, N., 2006. Petrology of metamorphic rocks in the Naein ophiolite (Isfahan province). M.Sc. Thesis, University of Isfahan, Isfahan, Iran. 194 pp. (in Persian with English abstract)