Introduction: According to important ecological roles of soil organic matter in stabilizing ecosystems, it is essential to consider soil organic carbon condition for managements of worldwide problems such as soil quality, carbon cycle and climate change. Also, organic matter is one of the main component of soil which have vital impress on its evolution. Therefore, assessing soil organic matter fate in various environmental conditions and its relation with environmental factors will be useful for management decisions. Determining soil organic carbon content, stocks and forms by the physico-chemical and micromorphological studies may respond to the question about soil organic matter evolution from the different point of views. Based on mentioned reasons, our research work focused on soil organic matter content, stocks and forms under various environmental condition of the forest ecosystem to find new aspects of its relation with environmental factors. Material and Methods: This research work was carried out in Arasbaran forest, northwest of Iran, which recognized as a part of the international network of biosphere reserves and has unique species of plants with special ecological properties. Sampling was carried out in a Kaleybar Chai Sofla sub-basin as a part of Arasbaran forest with eastern longitude of 46º 39´ to 46º 52´ and northern latitude of 38º 52´ to 39º 04´ . Based on the Amberje climate classification, the climate of the region is semi-humid and moderate. The soil moisture and temperature regimes are Xeric and Mesic, respectively. Hornbeam (Carpinus betulus) and Oak (Quercus petraea and Quercus macranthera) were identified as the main woody species in this area and volcano-sedimentary rocks were the geological structure. Primary site surveying showed 5 forest stand types such as Oak (Quercus macranthera), Hornbeam-Oak (Carpinus betulus-Quercus macranthera), Hornbeam (Carpinus betulus), Hornbeam-Oak (Carpinus betulus-Quercus petraea), Oak (Quercus petraea) along Altitudinal transects, that used as environmental parts with different conditions. In each environmental part, a soil profile was described and sampling was done for physical, chemical and micromorphological analysis. After preparing soil samples in the laboratory, soil physico-chemical routine analyses were carried out by standard methods and then the studied soils were classified on the basis of 12th edition of soil taxonomy. To achieve the main aim of the study, various aspects of soil organic matter evolution were assessed. Soil organic matter content was determined according to the Walkley– Black wet oxidation method and using alteration factor f = 1. 724 recommended by USDA. Variance analysis and means compare of soil organic matter content in surface horizons of different environmental parts were performed by using the SPSS software package and Dunkan's multiple range test, respectively. Soil organic carbon stocks were calculated for each soil horizon and weighted average based on profile depth was used to calculate this index for each soil profile. The prepared thin section for micromorphological study was examined under both plane-polarized light (PPL) and cross-polarized light (XPL) using a polarized microscope and explained based on standard terminology to identify various forms of soil organic matter all over the study area. Results and Discussion: Results revealed increasing of soil evolution with decreasing of elevation. Entisols, Inceptisols, Alfisols and Mollisols with different families were the soil observed along Altitudinal transects by decreasing elevation. According to the obtained results, environmental effects caused different soil organic matter content and evolution with various soil organic carbon stocks in each part. Improvement of environmental condition by decreasing elevation resulted in more evolution of soil organic matter, dominant of decomposed forms of organic matter and rise of soil organic carbon stocks from the highest part to the lowest one. Soil organic matter content in soil surface increased by elevation, although the main source of soil organic matter have better condition in lower parts due to ecological reasons. This inverse statue can be explained by special environmental conditions causing limited organic remnants decomposition in the highest parts. In the same trend with soil evolution, soil organic carbon stocks increased by decreasing of elevation. This trend refers to the relation of mentioned index ability with various soil-forming processes. Micromorphological study showed that organic intact remnants were the dominant forms in upper parts which changed to well-decomposed forms in the lowest parts. This observation revealed the occurrence of mechanical decomposition processes of organic remnants in high elevation while biochemical ones happen in the lower parts. Also, this distribution of soil organic matter decomposition processes can explain soil organic carbon content and stocks all over the study area. Conclusion: Elevation was identified as an important environmental factor controlling soil organic matter in the studied scale. Generally, results confirm the same trend for soil organic matter evolution and soil organic carbon stocks with soil development, especially in pedogenesis processes in relation to organic matter. Thus, it can be recommended to use soil map for management of soil organic matter under various environmental conditions in large-scale studies.

Isfahan is among the cities which has unique formal features in its physical structure.Despite the comprehensive and detailed plans prepared during the recent decades, the role of city scale in controlling and guiding the development of this city has been neglected.One of the most important reasons behind such negligence is the methods used for such planning. The suggested zoning plans, which are land-use based, were not able to use the features of the physical structure as a unique property of the city to improve the quality of the urban spaces. Thus, it is necessary to use a type of zoning which is based on historical and cultural features of the city and apply those qualities during the process of city planning.transect zoning is a new approach for city scaled zonings. It considers the components of physical structure of the city and decentralization in all aspects, which affect the formal structure of the city in urban planning. According to the above mentioned points, the goals of this study are to introduce zoning transect as a method for zoning lands and cities and to improve the transect zoning to be applied on some part of Isfahan in accordance with the local features and practical usage. The questions raised in this study are: What is transect zoning and what is the function of this method? How is it possible to make a transect zoning for Isfahan? The research method is descriptive-analytical. The results of this study show that features which describe the transect zones can be used for more efficient planning. Based on a formal point of view, these features can be used for changing the local features of the city.

Geographical and Altitudinal distribution of 234 populations belonging to 13 species of Aegilops in Iran after chromosome counting was studied. The relation between different ploidy levels, genome types and Altitudinal distribution was estimated. Results indicate that D genome type and tetraploids are much frequent at higher altitudes. Among the Aegilops species in Iran, Ae. kotschyi and Ae. tauschii Are low land elements while Ae. crassa prefers the highest altitude from the sea level.

Background and Objectives: Soil scientists have developed different mathematical equations and indices to be able to quantify soil development and to organize soil data. Soil properties will change during the soil development, which some changes can be made in the form of mathematical relationships as soil development indices. In this regard, soil morphological characteristics and laboratory data; have been considered by some researchers. Besides, attention to soil micromorphology as a method which can be associated with evidence relating to the sequence of pedogenic events and the processes which are not detectable by laboratory and field data, provided other developmental indices. The amount and distribution of extractable forms of iron in the soil profile are also indicated the stage and degree of soil development. The main objective of the present research was the comparison of different soil development indices (including forms and ratios of iron, magnetic susceptibility, color indices and modified Harden Index) related to different soils located on Kerman-Baft transect.Materials and Methods: Eight pedons on different geomorphic surfaces were selected during field studies. All genetic horizons of selected pedons were sampled and were transported to the laboratory for physical and chemical tests as well as magnetic susceptibility studies. The magnetic susceptibility of prepared samples in both high (chfbulk) and low (clfbulk) frequencies was measured by a Bartington magnetometer in soil science laboratory of Isfahan University of Technology. Finally, the percentage of frequency-dependent magnetic susceptibility (%cfd) was measured. In addition, undisturbed samples were taken from a number of horizons for soil micro morphological studies. The thin sections prepared for soil micro morphological studies were studied and interpreted based on Stoops guidline (2003) using a HP polarizing microscope.Results: Moving from Kerman toward Baft in the studied transect, due to increasing trend of elevation, more humidity was observed. That is why, pedogenic processes were also increased and iron forms and ratios showed this development trend regardless of local conditions. Due to effect of parent material lithology on soil minerogenic magnetic susceptibility, no significant relationship between this property and soil development indices was found. Correlation of various forms of Iron with three color indices of Harst, Torent and Alexunder showed that Harst Index was better than the other two indices for the study area. Moreover, since the parent materials of different pedons were not the same, the modified Harden Index was not adopted with soil development trend.Conclusion: Regarding the relationship between evolution and the age of the soil with various forms of iron, increasing the crystalline iron oxides from soil profile number 1 (dry climate) to soil profile number 8 (moist climate), represents a further evolution of soils.

Salinity is one of the environmental parameters that its impact on plant species diversity requires further studies. In this research, change of plant diversity was studied along a salinity gradient that was resulted from proximity of water table to the land surface in Incheh Borun plain due to the Altitudinal change in northern part of Aq-Qala city. A transect with the length of 1 km was laid out along one of the hills in the region. Sampling units (plots) with the size of 3´3 m were established at 100 meters intervals along the transect. A floristic list was compiled and plants canopy cover was estimated in each sampling unit in the direction of dominant Altitudinal gradient. Shannon-Wiener and Simpson indexes were calculated by using of PAST software. b-diversity was calculated between the sampling units using the Whittaker index. The relationship of salinity changes between sampling units along the Altitudinal gradient and Alfa diversity, Simpson and b-diversity was studied using the linear regression. Results showed that there are significant relationships between the altitude, soil salinity and plant diversity indices. Soil salinity increases by decrease of altitude and the biodiversity decreases by increasing of soil salinity. These changes occur due to increasing of salinity.

transect theory and approach have recently turned into one of the fundamental principles of urban design and planning in the urbanization systems in Europe, the United States and more recently the middle-east, its main goal is reaching the sustainable development patterns in urban areas. A consensus regarding the operationalizability of this theory and approach for creating a sustainable urban form, explains the necessity of analyzing and surveying its generalizability to Iran urbanization system. The following article tries to shed light on this new theory and approach (transect) and to analyze and discuss its probable advances and weaknesses on controlling and guiding urban form through the typology of its lineage theories and approaches.findings of the research show that the transect model is, in fact, a type of linear cross-section which takes advantage of nature ecological principles to lead and control of urban areas based on the urban character. Also, by reviewing the literature of the subject toward the transect model and its background theories and approaches and to defy its similarities and differences; typology was performed based on 8 criteria: philosophical orientation; elements of concern; how to use ecology as a basic discipline of theory or approach; urban design and planning paradigms; purpose of employing cross-sections; type of considered order; considered elements of the place, extent of theory or approach. Analyzing this theoretical framework shows that the transect theory has a relative improvement based on all of the typological criteria except paradigms of urban design and planning and considered elements of the place. Therefore, theorizing or expanding the theory and approach of the transect is recommended in order to solve its shortcomings and weaknesses along with attending to all of the aspects of the place and synchronizing with the paradigm of evolution as the superior paradigm of urban design and planning.

Hyrcanian forests in northern slope of Alborz support high bird richness and abundance same as central of Europe. In this study, efficiency of different methods including fixed-width transect, variable-width transect, fixed-radius point count and variable circular plot samplings were compared in order to present the most reliable methods for surveying and monitoring of diurnal forest birds in forested Alborz mountains. Three 1 km long transects and fifteen fixed and variable radius points which located 250m far from each other along the transects was performed. Each transect and point was visited 3 times during august 2008. One-way ANOVA was performed to analyze the data. The results revealed significant differences of bird richness and abundance between the points and transects sampling methods (F3,104=9.85, P=0.00 and F3,104=57.35, P=0.00 for bird richness and abundance respectively). In contrast, no significant differences in richness and abundance between variables and fixed transects as well as between fixed-radius point count and variable circular plot samplings were found. Overall our results suggest transect method yielded greater bird richness and abundance than point count method, therefore, they can be more useful for preparation birds listing in forest ecosystems, but this also depends on habitat characteristics.

Nuclear simple sequence repeats (nSSRs), together with 16 different enzyme loci, were used to analyze genetic diversity and differentiation among beech (Fagus orientalis Lipsky) populations along two Altitudinal gradients in Hyrcanian forests of Iran. Both enzymes and nSSR analyses revealed a high level of genetic diversity in natural populations of F. orientalis. The genetic diversity, estimated by expected heterozygosity, was 0.19 (by enzymes) and 0.65 (by nSSRs). Genetic variation across both markers did not reveal genetic structuring along Altitudinal transects. There was less genetic variation among Altitudinal gradients within transects compared to transect sites. Differentiation assays and analysis of molecular variance (AMOVA) indicated that there was a relatively low genetic differentiation among populations, and just 1% and 5% of the genetic variation occurred among populations by nSSR and enzyme data, respectively. Mantel tests showed that there was not a significant correlation between the genetic distances among populations and the distance of elevation. The results of the present study indicate that the relatively low genetic differentiation among F. orientalis populations at different elevations was not caused by ecological factors. These patterns suggest that higher rates of gene flow along Altitudinal gradients within transects, than between transects; a process that could question Altitudinal adaptation.

This study was conducted by the aim of study the species composition and diversity in the north faced slopes of Sabalan (altitude profiles of Lahrood-Shabil) along 7 transects in three elevation classes of 1500 to 2000m, 2000 to 2500m and 2500 to 2700m in the grass-shrubland dominated habitats. Plant specimens were collected in the fieldworks, and then species were identified using the checklists and reliable literature. Overall, 64 identified species were belonged to 48 genera and 22 families. Poaceae family with 9 genera and 16 species, Fabaceae family with 4 genera and 8 species and Asteraceae family with 6 genera and 6 species are the dominant family and genera. According to the Rankaier's system hemicryptophytes with 50%, therophytes with 31%, geophytes with 16% and chamaephytes with 3% are the growing life forms at the study area. In terms of geographical distribution, 42% of the species are belong to Iran-Turonian region, 22% of those to Iran-Turonian and Euro-Siberian, 12% are cosmopolitan, 3% to Euro-Siberian and other 21% is belong to other regions. From the identified species 6 of them are in threatened status based on the International Union for Conservation of Nature and Natural Resources (IUCN) criteria. Diversity and evenness of species were calculated using numerical indices. Results of numerical diversity indices (Simpson and Shannon-Weiner) showed significant change according to elevation. However, the evenness indices (Simpson and Smith and Wilson) show no significant change by elevation.