نشریه علوم و تکنولوژی محیط زیست
سال بیست و یکم شماره 3 (پیاپی 82، خرداد 1398)

Considering the effects of power plants locations on society, economy and environment, it is important to choose a suitable site for this facility. In order to find a suitable location for the construction of combined-cycle power plant, GIS can effectively provide a combination of the required information for site selection. This study aims to identify the most important factors in determining the appropriate place for the construction of combined-cycle power plants. The role and influence of each factor (distance from access roads, altitude, slope of the land, distance from the earthquake-prone areas, distance from surface water resources and distance of the fault lines) are also determined.

Using fuzzy membership functions, the standardized criteria maps were created in GIS based on the nature and role of these factors in the site selection. First, it was necessary to multiply these layers to their weights based on their priorities for combination of the criteria. Fuzzy AHP was used for this purpose. Finally, Ordered Weighted Averaging was used to overlay and combine the layers.

The results indicate that the northwestern part of Qazvin province is inappropriate for the intended purpose and eastern and southeast parts of the study area are forecasted.

Since the risk level of making decision is controlled at high, low or intermediate in combination of the layers by this method, the application of the results of this method will be acceptable, making decisions based on this method will have less uncertainty and the results of this method can be used with more confidence.

Heavy metals are considered as serious pollutants due to their toxicity, persistence in natural conditions and ability to enter and accumulate in the food chain. Therefore, this study was carried to assess the potential ecological risk and identify the source of heavy metals including lead, arsenic, cadmium and zinc in the surface water and sediments from Gheshlagh river, Sanandaj. For this purpose, 16 samples of surface water and sediment were collected. Then, concentrations of arsenic, lead, cadmium and zinc were determined by atomic absorption spectrometry. Moreover, potential ecological risk index (PERI) and enrichment factor (EF) were utilized to assess the ecological risk, and heavy metals pollution index (HPI) was used to survey the effects of heavy metals on human health. Multivariate analyses such as correlation analysis, principal component analysis (PCA) and EF were used to identify human resource potential of arsenic, lead, cadmium and zinc. The results showed that the average concentration of a group of elements, including Pb, Cd and Zn, was higher than background levels, whereas average concentration of As was significantly lower than the background levels. Enrichment of the studied heavy metals was obtained as Pb> Zn> Cd> As in Gheshlagh river.  The results of PERI showed a low risk for Pb, As and Zn and a moderate risk for Cd in the samples under the influence of road traffic. Considering the results of EF and PCA, it can be concluded that the concentration of As has been mostly affected by the geological structure. Pb and Cd concentrations in four sampling areas were equally affected by agriculture and road traffic. It was also found that the concentration of Zn is influenced by residential wastewater.

Soil is the basic component of environment and the main source of food production and its contamination can cause pose many challenges for humans and other living organisms. Although many studies have been done separately to eliminate organic pollutants such as benzene and phenolic compounds from soil, a few studies yet have been done on the removal of crude oil which contains different types of hydrocarbon compounds from the soil. The aim of this study is to determine the removal of crude oil from the soil and provide a comprehensive model. In this study, the ex-situ soil washing method with surface active agent has been used to remove crude oil from soil. For this purpose, first, the soil was artificially polluted with crude oil and then the effects of various parameters such as surfactant concentration in aqueous solutions, the initial concentration of contaminant in the soil, pH, volume of detergent solution, stirring rate, duration of the process and system temperature were evaluated. The results showed the optimal conditions for the removal of crude oil were concentration of surfactant in aqueous solution of 0.5% (w/w), initial concentration of crude oil of 5% (w/w), detergent solution pH=11, detergent solution volume of 50 ml, stirring rate of 200 rpm, experiment duration of 15 m and temperature of 45 °C. In optimal condition, about 96% of crude oil was removed from the soil. According to the obtained results, surfactants can be used as a proper substance to remove oil contaminants from soil with a good efficiency.

Many agriculture and natural resources have turned into desert due to overuse and mismanagement of groundwater. The main cause of desertification and land degradation, in addition to natural factors, is improper human activities that lead to some consequences such as salinity and lowering the groundwater level. In this regard, the degradation severity assessment of groundwater resources was done in Shiraz plain to plan for encountering the degradation of groundwater resources. In this study, the modified IMDPA model was used to determine the severity of groundwater resources degradation. The final map of groundwater resources degradation was created by integrating the information layers of indices of water criterion. The results of this study indicated that about 55% of the main part of the plain is under moderate hazard class of water degradation and about 30% of it is under severe and very severe hazard classes of water degradation. The results of this study showed that the electrical conductivity index had the greatest impact on the degradation of groundwater resources in Shiraz plain. Moreover, it was found that the proposed model has a good performance in estimating the severity of groundwater resources degradation. Therefore, the model is recommended to be applied in similar areas to determine the severity of groundwater resources degradation.

Natural and artificial radioactive nuclei exist in water, soil, stone and air, and all humans are exposed to nuclear radiation. Some human activities, such as application of the weapons containing depleted uranium in wars or nuclear accidents, cause an increased environmental radioactivity. Due to proximity of Hoveizeh region to the war zones in Iraq, it is important to study the radioactivity of soil in this region. In this study, 10 soil samples were collected from Hoveizeh region near the Iraqi border. The specific activities of radionuclides were determined using the gamma ray spectrometry method employing a high purity germanium detector (HPGe), GCD30195 model with 30% relative efficiency. The radium equivalent activity, internal and external hazard indices (Hin and Hext) and radiological parameters and Pearson correlation coefficient among the values of radium, thorium and potassium were calculated. The mean specific activities of 238U, 226Ra, 232Th, 40K and 137Cs in the soil samples were obtained as 34.09, 34.96, 34.84, 384.68 and 5.64 in Bqkg-1 respectively. The values of Hin and Hext in the samples varied from 0.37 to 0.49 and from 0.25 to 0.37, respectively. Pearson correlation coefficient between 226Ra and 232Th was obtained as 0.59 showing a moderate correlation. The average radium equivalent of the studied samples was obtained as 114.39 Bqkg-1 which is less than the world average value (131.69 Bqkg-1). All the quantities of radiological parameters were within the permissible level and close to the global average. No traces of depleted uranium were observed in the region.

Investigation of environmental changes is a necessity for maintenance and optimized utilization of natural resources. For this purpose, field measurements and region sampling, which are time-consuming and expensive, are implemented. In this study, precipitation, temperature and water level variations were investigated in the study area and evapotranspiration rates were calculated using Blanney-Criddle method. Moreover, remote sensing techniques such as Normalized Difference Vegetation Index (NDVI) and water index, MNDWI, were used to investigate the environmental changes. The study area is located around Hoze Soltan Salt Lake beside Tehran-Qom highway. The Landsat ETM satellite images of 2002 and OLI of 2013 in May were prepared to be used in this study. Using MNDWI, the Hoze-Soltan Lake area were estimated as 7835.857 and 6265.062 hectare in 2002 and 2013, respectively, indicating the reduction of lake area in 2013. NDVI index revealed that vegetation cover increased from 65.33 hectare in 2002 to 2942.61 hectare in 2013. Moreover; investigation of rainfall volume, temperature, evapotranspiration and water level using the available data revealed a declining trend of rainfall volume and water level and an increasing trend of temperature and evapotranspiration in the region. The results of this study indicated that some parts of the region around Hoze-Soltan lake were not inundated in 2013 because of the decreased water level. This has provided a good growth condition for more plants and for cultivation in some parts. The increase of vegetation covers and consequently the increase of evapotranspiration along with water level withdraw and precipitation declining trend emphasize the reduction of lake area during the study period as presented by the remote sensing techniques.

Bashgol protected zone, with an area of 6/25198 hectare, is located in Qazvin province. Climate and weather in the area fall within the category of semi-desert areas. The vegetation in this area include the families of pepper, grasses, Compositae, and considering the protection and optimal vegetation in the area erosion is low. There is diversity of fauna and113 species in this region. In this study, it has been attempted to guarantee the stability of land by allocating the land uses fitting the land potency.
There are several methods for evaluation of ecological capability. According to the objectives in four areas, the conventional overlay method was used to assess the ecological capability which is in fact a basis for land use planning.
the wildlife habitat maps were overlaid in Bashgol protected area. The areas specified in terms of density of wildlife, sensitive habitats and ecosystems, rare and unique wildlife and having a certain genetic value along with the exquisite landscapes, animal passages, ecotones and the areas with a slope of over 70% were classified as the first priority protection (first class). The areas which fall outside the first class but were a wildlife habitat or passage were defined as the second class (the second priority protection).
Discussion and Overgrazing and illegal hunting, as the main challenges in the study area, have forced the wildlife, especially Central Alborz sheep and plain species, to leave their habitat and threatened their population. Therefore, these factors have made Bashgol a good candidate for being assigned as a protected area in the 4 regions managed by the Environmental Protection Agency. In land use planning in this area, it has been attempted to put all the sensitive areas which are valuable for protection under management only for biodiversity conservation.

The world’s population is ageing and virtually every country in the world is experiencing growth in the number and proportion of older persons in its population. It is predicted that old population will double from 2015 to 2030 in Iran. Actually, more than half of the world’s population lives in urban areas, and urbanization rate is over 70% in Iran. Therefore, the main purpose of this study is to investigate the impact of population ageing and urbanization on air pollution over the period of 1971 to 2013 in Iran.

In this study, based on the results of variables stationary, the Autoregressive Distributed Lag (ARDL) approach was applied.

The results revealed that the relationship between old population and CO2 emission per capita is inverted U-shaped and statistically significant, and CO2 emission initially increases with the increase of old population and then drops with the increase of old population. Moreover, the results imply that a relative increase in urbanization in the short and long terms is associated with the increase of CO2 emissions per capita. It was also found that gross domestic production and energy consumption per capita positively affect CO2 emissions per capita in the short and long terms. Technological advances have a significant positive effect on per capita CO2 emissions in the long term.
Discussion and

In this study, according to the urbanization coefficient which has the greatest influence on pollution emissions (3.63 in the long term), the measures should be taken by policymakers to minimize the damage of urbanization growth to the environment. In other words, urban development plans should be designed in harmony with the environmental issues.

The majority of the Earth's surface is covered by water bodies whose beds provide very diverse habitats for aquatic. Since benthos communities choose particular type of bed as their habitat, study of sediments and organisms in the substrate environment can help the environmental assessments. This study was performed to assess the ecological condition of the muddy substrates using macrobenthos communities in Sajafi region of the Persian Gulf. Sampling was done in fall 2009 at 20 stations with 3 replicates at each station to determine organic matter and grain size of the sediments. Measurement of water chemical and physical factors and identification of macrobenthoses were carried out using Hach-HQ40d and Grab devices. Diversity indices of Shannon - Wiener, Simpson, Camargo uniformity, Margalef and Menhink species richness were calculated. Nonparametric Kolmogorov-Smirnov test was used to evaluate the distribution of the data, the oneway ANOVA and Spearman correlation tests were used to compare and evaluate the relationships among diversity and density indices, chemical and physical factors and sediment parameters, and Welch pattern was used for assessing the environmental pollution. Totally 8 groups of Benthos comprising 81 species were identified. The most frequency percent belonged to Gastropoda with 43.03%, Polychaeta with 29.31 % and Bivalvia with 20.53%, respectively. The highest value of Shannon index at station 11 was 4.523. The highest values ​​of diversity and dominance of Simpson, Camargo evenness, and Margalef and Menhink richness indices were 0.948, 0.158, 0.828, 5.830 and 2.830 respectively. The maximum and minimum values ​​of frequency were 4920 and 560 macrobenthos per square meter, at Stations 10 and 17 respectively. Discussion and According to the results of the measured indices, which confirmed the high diversity of macrobenthos in the muddy bed of Sajafi area, it can be concluded that the study area has a high potential to preserve the environmental richness of benthic invertebrates.

Determination of forest growth is one of the most important goals and tasks in forest management, which has always been accompanied by challenges in the implementation section due to the complexity of volume and growth process determination. Knowing the volume of standing trees and growth is mandatory in an accurate planning. The volumetric growth of forest stands is a basis for determining the annual cutting in planning and management of forest exploitation. Harvest of this amount of wood leads to forest sustainable development and, to some extent, can provide the wood needed in the country without raising a problem for these valuable resources. This study was done in Gorazbon district of Kheyroud forest in Mazandaran province. 258 permanent sample plots were measured in the circle area of 10 R. Then, volumetric growth and number of trees in forest stands were directly calculated. Results showed that the average tree numbers were 298.15 and 290.4 stems per ha in 2003 and 2012 respectively. The growing stocks were 335.8 and 367.7 sylve per ha sustainable forest management. Although beech constitutes 31% of the total number of trees in Gorazbon district, it accounts for 57% of the whole trees in terms of standing volume. Annual volumetric growth is 4 sylve per hectare and growth of tree number is -5.8 per hectare annually. Finally, it can be concluded that preparing an inventory by permanent sample plots provides the necessary information and detailed statistics to determine the volumetric growth and number of trees to contribute to proper management and decision making. Moreover, harvesting this volumetric growth can help the economy and lead to sustainable development of the forest at the same time.

Looking at the long history (at least ten thousand years) of human settlement, we can realize that urban environments in their current shape and form can be considered a relatively new phenomenon. Despite covering a small area of the earth’s surface, urban environments house the majority of human population. The man is always faced with natural and man-made disasters and crises. Although it is not possible to avoid crisis, but its damage can be reduced by proper design. Thus, evaluation of urban resilience is one of the crucial factors to gurd the city against the natural and man-made disasters. Increase of the resilience of cities can minimize the damage caused by natural disaster. The importance of this issue is as high as some have referred to it as a new paradigm in urban evolution. In this study, it has been attempted to use a deductive approach with a systematic approach. Numerous studies have been carried out to determine the relation of resilience dimensions and components with the urban land use. In the end, several dimensions and criteria considered more prominent by the experts (specialized in the field of environmental planning, urban planning, and geography) have been proposed for the concept of land use resilience It has been attempted to determine both diminition and resiliency of urban lands criteria and also sustainable development approach though applying inductive approaches with system concept. Finally, by drawing the related conceptual model, effective steps will be made for reduction of vulnerabilties and improving cities and their systems.

Waste Management Organization (WMO) has always sought to educate and promote citizens in waste separation from the source. WMO, by developing the training programs, seeks to teach the concept of waste management operations to public citizens. This can be done through the municipal waste management educators. However, the question that should be addressed in this study is that: what challenges the municipal waste management educators are faced with in carrying out their duties, knowing that the problems and challenges of a career in teaching are usually considered as barriers. This study was carried out based on the questionnaires of Akphilet and Kout, in which 172 educators, working in municipal WMO, responded 5 questions on the Likert scale. Occupational challenges check reveals that the place of employment has not provided the necessary opportunities for learning and professional development. Yet, 59% of the educators believed that the organization needed to encourage learning and did not provide the basis for more professional development. However, the teachers of 20-25 and over 35 years old are seeking professional development opportunities more than others, and people become less willing to use their professional growth opportunities with the increase of their experience. The results showed that the influence of organizational factors of progress is more than individual factors. The people believe that the organization have to provide the basis for development and professional growth rather than attempting to make development and professional growth by themselves. The regression coefficient calculated for professional development measures showed that different parts affect the process of professional development.

The first step in proper management of forests is having enough information about growth, development and how the forest stands structure are influenced by environmental factors. Considering the importance of forest stands in the north country and environmental values of the study area, structure of the existing species in Dashtenaz forest protected area in Mazandaran province has been investigated using the nearest neighbor indices. To investigate the structure of the study area, 56 hectare of the forest stands were statistically analyzed, and Clark and Evanes, Uniform angles, Shannon-Wiener, Mingling, DBH dominance and DBH differentiation indices were used to investigate the structure. The results showed that the mean Clark and Evans and uniform angles indices were 0.70 and 0.55 respectively, indicating a distribution between random and cluster patterns. Mean indices of Shannon-Weiner and Mingling were 0.40 and 0.06 respectively. Knowing that the study area is mostly composed of oak, the Mingling index value was calculated to be low​​. The mean DBH dominance index was calculated as 0.50, indicating the dominance of DBH of Quercus Castaneifolia and recessivity ofUlmus Glabra. Zelkova Carpinifolia was medium in terms of DBH dimension. Also average DBH differentiation index was calculated as 0.32, representing a medium difference between the trees next to each other in terms of DBH dimension. The indices used in this study can be used to describe the structure and ecological property of different species of trees.

In this study, the parameters related to growth and mortality of Liza abu in Shadegan wetland were studied. The sampling was carried out monthly to determine the length and weight at five stations including Douragh (Mahshahr), Rogbeh, Khoorosi, Salmaneh and Ateish. During implementation of the project from March 2013 to February 2014, a total of 493 fish were caught and transferred monthly to the laboratory for biometric analysis. The average lengths (±SD) in millimeters for male (20±138) and female (18±138) as well as the average weights (±SD) in grams for male (13±33) and female (14±33) were obtained respectively. The length-weight relationships for female (R2=0.89, W=0.00001L3.33, N=282) and male (R2=0.88, W=0.00001L 2.98, N=195) Liza abu were obtained. The values of length (247, 220 and 247 mm), growth parameters (0.56, 0.74, and 0.66), total mortality (2.83, 2.90 and 2.98), natural mortality (1.22, 1.36 and 1.22) and fishing mortality (1.73, 1.36 and 1.76)  for male, female and total were calculated, respectively. Considering the growth and mortality parameters obtained from American fisheries society (AFS) indices, this speciesis classified as a low vulnerable group

The restoration and maintenance of landscape connectivity and integration of its elements require reliable and efficient communication models and indicators. Habitat fragmentation is a dynamic process that leads to major changes in the pattern of habitat in a landscape. It describes, generally, the fragmentation and division of vegetation cover and habitat into smaller remnants. Modeling based on the least-cost path analysis is a method used to identify the potential corridors among the isolated habitat patches. This study aims to locate suitable habitats for the Persian Leopard (Panthera pardus saxicolor) in Golestan National Park and Khoshyeilagh Wildlife refuge and the area between these habitats. Given the close proximity of these habitats, their connectivity for the safe movement and energy consumption minimization of the Persian Leopard has vital role in gene flow and prevention of genetic isolation of the species. The habitat suitability for the Persian Leopard in the study area was analyzed using the ecological niche factor and biomapper software. The data layers used as effective variables in the presence of the species are: elevation, slope, vegetation index (NDVI), distance from roads, distance from villages, streams, and rivers. The possibility of corridor existence between the two habitats was studied by the least-cost path analysis. The results of probable map corridors proved that the northern parts of Khoshyeilagh wildlife refuge and the southern parts of Golestan National Park are the shortest and the safest pathways for the species movement. Conservation of these regions is of high importance, because the best route through which the leopard can move between the two habitats are located in these sections.

Due to the growth of population and consequently the crisis caused by increase of energy demand, management of energy consumption has become inseparable from the issue of sustainability. Therefore, in this study, with a special emphasis on the importance of energy saving, optimization of energy consumption in housing sector are discussed through the contemporary native pattern designing in hot and dry regions. Hence, the required information was collected by investigating the energy consumption in this sector through different patterns and designing the energy-efficient patterns to achieve this important issue. Due to the fact that the study was done on a case studies in Yazd city, the designing style of the buildings such as (direction of the thickness of the walls, height of the inner structures, etc.) and the elements used (porches, plants, wind, etc.), which have a direct effect on energy efficiency, are studied. According to the results, the pattern of vernacular architecture and modern residential patterns for reducing energy consumption led to similar outcomes by implying that the proposed method can be efficient in reducing the energy consumption

I this study, morphological characteristics of two populations of Aphanius dispar from two sulfur springs of Ahram and Dalaki in Bushehr were compared investigated. Totally sixty specimens, 30 from each spring, were caught by cone net. The morphological results were first standardized by Beckham equation and then investigated by principal component analysis (PCA), discriminant function analysis (DFA) and clustering analysis (CA). Wilks' Lambda test was used to compare the differences observed in the studied groups. Among the 78 truss intervals analyzed, 42 intervals showed a significant in the populations of A.dispar in Ahram and Dalki rivers (P<0.05). The studied populations are distinguished especially by pre anal, body height, distance from pectoral fin to ventral fin, distance from pectoral fin to anal fin, caudal peduncle length, head length, pre orbital, pre ventral and dorsal length. Apparently, the morphological differences between the two populations signifies distinct stocks in the studied rivers.

Environmental issues and the cities losing their natural context have motivated the urban designers to seek for reclamation of urban critical elements, such as green spaces and natural landscapes, and apply new technologies to achieve this goal. Vertical green surfaces are one of the technologies which have become attractive during the recent years. This technology, like any new system, has some advantages and challenges. One of the important challenges for these surfaces is their financial efficiency. In this study, Cost Benefit Analysis (CBA) is used to evaluate the mentioned challenge. Considering the financial gain of these surfaces along with the cost of their installation and maintenance, a better perception of their financial efficiency would be obtained. The costs of implementation and maintenance were calculated based on the data from relevant companies in Tehran and the financial gain was estimated by reduction of energy consumption in a simulated building with green wall. Findings of this study show that costs of implementing and maintaining green surfaces is much more than what is gained due to reduction of  cooling/heating loads in a building. Due to high costs of green walls installation and maintenance, they do not seem to be affordable by considering the reduction of energy consumption costs. Besides, other mentioned issues including oxygen production, carbon tax reduction, increase of building real estate value, energy reduction in the power plants, and reduction of costs of air pollution which can reduce the associated costs are related to the application of plants but not solely green walls. Hence, by applying various forms of vegetation in green spaces, the above-mentioned benefits can be achieved at very low costs.

Nowadays, giving identity to urban areas through preserving, promoting the character and empowerment (function and form) of the buildings with historical–functional value, which has a prominent role as a symbol in collective memory and mental status of people, is of high importance in urban design discussion. Seemingly, taking an action which provides these buildings with the opportunity to be viewed and provides their position and environment with the quality of visual permeability, can be considered as one of the empowerment strategies for these buildings. In this study, a descriptive-analytical method with literature review of the resources and documents in the context of visual studies and also case study by interview and observation methodology in the field studies have been used. Also, the streetscape of Seyyed Alaedin Hossein Shrine in historical and traditional district of Shiraz was analyzed. The results of this paper showed that the views and vistas, as the main elements of urban landscape visual system, are the elements which can facilitate the visual permeability in the buildings with historical–functional value through regulations. This study represents the concepts related to views and vistas and their role and position in visual management and visual studies. Also, this study reviews the universal rules for purposeful and conscious design of views on the buildings with historical-functional value within the city. In this paper, using the verified regulations, the strategies for improving the quality of the streetscape of Seyyed Alaedin Hossein Shrine in Shiraz have been presented.