مجله پژوهشهای محیط زیست
سال پنجم شماره 9 (بهار و تابستان1393)

Visitors use the tracks for many reasons and in different types. The determination of users destinations and preferences in walking tracks designing are very important. Scenic and viewing points are important factors for visitors of recreational track, so aesthetic expectations ought to be considered as part of a thoughtful track design. Different approaches for assessing the scenic qualities of landscapes have been developed in the last few decades. Two basic approaches in this field include expert/design approach and perception-based approach. In this paper scenes and viewing points of 10 existing walking tracks in natural recreational area of Ziyarat Basin were assessed according to the perception-based approach. Therefore, a field survey using GPS receivers was conducted to determine viewing points on the study area and at each viewpoint photographs by using of digital camera that could be used for visual quality analysis. The data was analyzed in was taken ArcGis9.3. Finally, according to the results of viewing point's analysis, walking tracks were classified in three degrees (excellent, good, and moderate) based on scenic quality. The results showed that Ziyarat basin walking tracks provide the possibility and opportunity for watching different types of visual landscapes in this area. Determination of walking tracks and viewing points, quality assessment of these viewing points and introducing the tracks based on the scenic quality via perception approach could be used as a suitable guideline for better management recreation area. In this study we have tried to provide a pattern for better management of these areas and increasing visitor's recreational experience quality from a natural recreational area by introducing one of the visual assessment methods.

With regard to non-marketing values of environmental resources and evaluating them with real prices, this research has tried to analyze and compare both practical recreation and conservation of Lar Lake’s dam which has a crucial role as an important natural resource in Iran. Therefore, in this research such diverse methods, as a Contingent valuation method, the questionnaire of Double Dichotomous Choice and Logit qualitative model have been used. The information related to this study was collected from 230 visitors based on random sampling in 1391. Here, a recreational value of Lar Lake’s dam was estimated 7626.2 rial ($2- 3) per person per visit. The average of inclination to monthly pay per person, in order to estimate a preserved value of this place was 3716.6 rial ($1.3). According to the results of both estimations, there were same outcomes for suggested variables, monthly revenues, and the rate of satisfaction. The level of education has a significant impact on pursuing people to accept the suggested fees for conservational values than recreational ones. Apart from that, ethnic minorities have noticeable desire to keep conservational values of this resource safe, compared to the other visitors.

Green spaces in urban areas, especially in large industrial cities entail different implications. The green space improves the environment of the cities and on the other hand it creates proper conditions for the recreation and leisure of the citizens in terms of distribution of urban green space. In this research, maps of parks was depicted by digital atlas of Tehran parks and by using of ArcMap and IDRISI software, Then by using applying selected landscape metrics including (CA, PD, PLAND, MPS, LPI, LSI, MNN, Shape-MN), and using Fragstats software, a series of quantitative data about spatial pattern of Tehran parks was resulted. Composition, configuration, expanse and continuity of parks were also analyzed. Only six percent of the landscape was assigned by the green space activity studied in three neighborhood, district, and regional parks classes. Neighborhood parks have the best spatial pattern in comparison with other classes and spatial pattern of regional parks were unfavorable in comparison with neighborhood and district parks.

Increasing use of forest parks has been resulting in concerns of how people behave to these protected areas. Some believe that psychological factors like place attachment and environmental attitude have great influence on environmental behaviors. The aim of this research was to investigate relationships between mentioned factors among visitors of forest parks in Golestan province. Results showed that increasing distance between living place and forest parks decrease place attachment. Married people have more place attachment than single ones. Findings indicated that there was a positive and causal relationship between visitors’ place attachment and park- specific responsible environmental behaviors. Furthermore, this research showed that place attachment is better variable than environmental attitude to predict environmental behavior.

One of the Environmental Issues that concerns the International Community is the problem of the Climate Change. Increases in greenhouse gases concentration in atmosphere resulting from human intervention in nature has increased Global temperature gradually. to combat against this phenomenon, the International Community has tried to ratify the United Nations Framework Convention on the Climate Change and the Kyoto Protocol and held several Conferences and Meetings in order to respond against the Climate Change. In this article I have tried to describe legal practices of the International Community regarding to the Climate Change by using the analytical – descriptive method for the time periods 1972-2011. For this purpose I have used International legal instruments relating to the Environment, as data.Results show that; although efforts of the International Community toward combat against Climate Change have been notable and widespread, it seems that more practical and effective steps must be taken especially by industrialized countries. It seems that cooperation of the industrialized countries have an important role in resolving of this crisis.

In order to analyse spatial and temporal trend of extreme Warm days of Iran, mean daily temperature data from 663 synoptic and climatologic stations of Iran for the period 21/03/1961 to 31/12/2004 were used. Then, applying Kriging method, the temperature of 15*185 Km pixels was interpolated. The days accompanied with extreme warm were identified using Normalized Temperature Departure (NTD) index. According to the index, the days with NTD ≥ 2 selected as extreme warm days. Then a trend analysis applied to the extreme warm days for each month of year. The results show that the number of extreme warm days in Iran represents no trend in December, February and March. East, south, center and southeast parts of Iran show positive trends during August, January and May over large areas. While in north and west of the country over small areas negative trend was observed during Mars and February.

Hydrology has had an important role in shaping human settlements as one of the most important environmental factors. As part of the Northeastern catchment of Iran, Neyshabur plain is located on the foot of Binalod mountain range, and is composed of a plain and foothill lands. There are numerous rivers in Neyshabur plain that emanate from Binalod Mountain, of which excess water is drained by Rude Kale-Shur in rainy seasons from the southwestern part of the plain. This study is based on collection of material documents obtained by stratigraphy method in a prehistoric settlement of Shahrak Firoze. Shahrak Firoze is a settlement formed in the margin of one of the most important rivers of Neyshabur named Farub Ruman in late Bronze Age, and analysis of its cultural layers as the statistical community under study shows that hydrology has been important in chronological formation and continuation of the settlement. Analysis of archaeological material of the statistical community also shows that prehistoric settlements in Neyshabur plain have been closely related to water resources. As the rivers of this plain have been torrential in rainy seasons with flood, in the long process many settlements such as that of Firoze have become errant in one period, and have been settled without any specific pattern.

Surface water pollution by chemical, physical, and biological contaminants all over the world can be considered as an epidemic problem. To decrease the negative impact of these pollution sources, offering a suitable model for water quality management is known as a key step to improve the quality of water resources system. In this study, given that Sefidrood River is one of the most polluted rivers of Iran and studies in this area has been very limited, we provide a framework for managing the river's water quality based on the canonical correlation analysis (CCA). For this purpose, data from 13 stations, located from the next of the Sefidrood Dam to the Caspian Sea, was used by CCA to determine the parameters of the relationship between physical and chemical pollutants in two period of wet (March) and dry (September). In general, our results suggest a strong relation between physical and chemical parameters in both wet and dry seasons. Therefore we can say as a result that the source of the both pollutant parameters in both high-water and low-water can be the same. Due to the fact that the source of chemical pollutant parameters in a basin is often caused by human induced sources, we can conclude that the origin of physical pollutant parameters, according to the CCA results, is the same as chemical pollutant parameters. So based on the results of this study reducing the human induced pollution sources is an important step in monitoring maintenance and quality improvment of this important river.

Risk assessment is a process of determination of risk quantity and quality using potential hazards of the project as well as considering the sensitivity or vulnerability of the surrounding environment. The main purpose of this study is determination of criteria and estimation of rail lines environmental risk by integration of multiple criteria decision making method and ecological risk assessment using YAPP Technique. Thereby, in the current study, the western railway corridor of Iran (Samangan- Kirmanshah- Khosravi route) which has the approximate length of 582 km was selected as a case study. The software that was used in this study was Expert Choice. The of inconsistency ratio were determined using Delphi Questionnaire and software Arc GIS 9.3 to produce impact intensity maps. Risk zonation of the western railway corridor of the country revealed that about 80 % of all length of the mentioned route has a low and negligible level of risk. The lowest risk belongs to the places situated at 155 to 153 km of the mentioned route, (near the city of Tuyserkan- Hamedan Province) as well as an area located at 479 km of the route (Sare Pole Zahab city in Kirmanshah Province). The medium risk level is observed between 80-47 km of the route near the county of Malayer (located in Hamedan Province) and the kilometers240-250 between Sahneh and Hersin (situated in Kirmanshah Province). Areas in the 485-480 km of the route located within the city of Kirmanshah (Kirmanshah province) are known as high-risk area due to deployment of the plan on lands prone to lands lide.

Petroleum warehouses and storage tanks are one of the major sources of air pollution. Therefore, this study aims to identify, assess and manage risks of air pollution in the central warehouse of Yazd Oil Products Distribution Company (OPDC). In this study, FTA Method was applied to identify environmental risks while E-FMEA was used to assess the risks. Based on the results of risk assessment, the highest RPN (equal to 336) is related to air pollution risk caused by respiratory and operational evaporation of the product due to lack of sealing of connectors. The second highest PRN equal to 280 is associated with operational evaporation of the product and the environment heat. In the pipeline, the highest RPN (tantamount to 180) is related to respiratory and operational evaporation of the product due to lack of sealing of connectors, while at loading platforms, operational evaporation of the product during its receiving and transmitting with RPN of 360 is identified as the most important air pollution risks. After identifying and assessing the environmental risks of air pollution, GIS Software was applied for zoning the air pollution. Accordingly, the risk map of air pollution on the site of oil storage was prepared. The results of the zoning suggested that the air pollution rate caused by NMTHC was occurred at Storage Section. Besides, the highest air pollution caused by SO2 was occurred at the southern side of the warehouse. Finally, risk management strategies as Kahab Project were proposed for Yazd Oil Products Distribution Company.

Air pollution has particular importance due to the fluid nature of air and it is one of the most important environmental problems in urban and industrial areas which threaten human health. Two main important pollutants in the air are suspended particulate material in the air and fine dusts phenomenon. Fine dusts phenomenon isn’t limited to geographical boundaries within the country, but now it is a regional problem. Recognizing of the quality and quantity of fine dust has an important role in determining their origin and planning to find out how to deal with and eliminate them. In this respect, due to the possibility of presence of metals in particulate matter, analysis of Teflon and fiberglass filters installed in air pollution monitoring stations in five provinces of Iran, were selected to measure at the time period when there was the highest pollution. In this study, the metals included. Pb, Ni, Hg and Cd in air filters (Teflon or Fiberglass), the installed filters in air pollution monitoring stations (at Hamedan, Sistan and Baluchestan, Hormozgan, Kirman and Zanjan provinces) were collected when there was the highest pollution. Then metals were detected by atomic absorption spectrometry after acid digestion. The results showed that the measured amount of Lead and Mercury in both types of air filters (Teflon and Fiberglass) in all provinces are below the international objective standards (WHO, EU Target, Federal and California) of Lead and Mercury. The concentrations of Nickel and Cadmium in both types of air filters (Teflon and Fiberglass) in some stations are below the international objective standards (WHO, EU Target) of Nickel and Cadmium and in others the concentrations of Nickel and Cadmium are the same as level of international objective standard ranges.

Nowadays, human is faced with water scarcity and many more problems which are due to population growth and industrial development. Therefore, many people around the world tried to overcome water shortage by dam construction and storing surface water when water is not available naturally. However, such activities together with climate changes may have negative impacts on inflow water quality and quantity. Nevertheless, the amount of evaporation from surface of water and thermal stratification may also change water characteristics (qualitatively, physically, chemically and biologically). Knowing how water quality changes in long-term period is important. Long-term study of water quality conditions in different layers of the reservoir could help determine the best layer for water intake and also to improve reservoir conditions. In this study, Karkheh Dam was selected as the case study. Using meteorological and river discharges records as well as water quality parameters such as temperature and dissolved oxygen of Karkheh River in different level for a period of 40. For simulation of reservoir behavior, the two-dimensional CE-QUAL-W2 model was used. With the help of this mathematical model the temperature and dissolved oxygen profiles were obtained. The results indicated a strong stratification period from mid of June to late of October in all years. However, a relatively weak stratification was obtained for April, May and November. In addition, in February thermal mixing phenomenon occurs, because, dissolved oxygen is strongly related to thermal stratification and fluctuates vertically according to temperature associated to each layer. Finally, results showed that the best level for water intake during strong stratification was between 170m to 180m. Otherwise, there is no limitation for water intake since stratification is not significant.

Sustainable Forest management is process that includes planning, implementation and monitoring. This process calls for criteria and indicators framework. On the other hand, forest ecosystems are increasingly considered as resources that must be managed for a wide range of ecological, economic and social values. These changes need criteria and indicator framework by which sustainable multifunctional forest management can be monitored. The Aim of this study is to develop criteria and indicator frameworks for ecological function including conservation, protection, conservation, and recreation function. For this purpose, Analytical Hierarchy Process and experts’ opinions were used and initial criteria and indicators were weighted. Final framework consists of 7 criteria, 25 indicator and 29 verifiers. Formulating these criteria helps monitoring the forest’s functions and can be used in determining, measuring, analyzing and assessing the sustainability of the studied area.

Greenhouse effect is one of the most severe current environmental problems. Forest ecosystems with their complex structure and function can play an important role in mitigating the emissions of CO2 as the most important greenhouse gas. Forest biomass and soil can be considered as the sinks of carbon. Many factors such as canopy cover percentage, forest type and species diversity, of species age structure, environmental conditions, and forest management methods affect the carbon sequestration. In this study, carbon sequestration in soil and plant biomass in pure and mixed beech stands of Gorazbon district in Kheyrud forests was estimated and valued.The amount of carbon stored in forest tree foliage and ground was estimated using the photosynthesis formula and the sequestration of carbon in mineral and organic soil horizons was determined using experimental methods, Walkly–black and oven respectively. The results showed that there is a significant difference between amount of carbon sequestration by the mixed and pure beech stands in both plant and soil biomass and the pure stand stores more CO2 than mixed one. Finally, the economic value of carbon sequestration function was estimated using cost avoided damage method. The results revealed that the average value of pure beech stand is 9.5 million Rials ($ 320) and 8.3 million Rials ($ 275) ha/year respectively, in terms of carbon sequestration function.

This study was designed to examine the effects of environmental variables affecting density and diversity of cavity nesting bird community in Golestan National Park. Density and diversity of birds and their association with environmental variables were studied using distance sampling method and ordination procedure. Birds and environmental variables were detected within a 25 m radius of each of 122 sampling points. The first axis of CCA successfully separated two groups of the birds. The first group (namely secondary cavity-nesting birds), including Wren, Great Tit, Coal Tit, Robin, and Red-breasted Flycatcher had positive correlation with the number of trees less than 10 m in height, the number of trees with dbh of less than 20 cm and 20-50 cm. The second group (namely primary cavity-nesting birds), including Great-spotted Woodpecker, Lesser-spotted Woodpecker, Black Woodpecker, Nuthatch, and Treecreeper had positive correlation with tree height, snag height, snag dbh, snag decay stage, log height, log dbh, log decay stage, and the number of trees with dbh more than 100 cm. The number of dominant species (N2), Shannon diversity index and Camargo evenness index had the highest values in relation to the height and dbh of sangs, the height and dbh of logs, the number of tall trees with dbh more than 100 cm and advanced stages of decay, while the lowest values of diversity indices were correlated with the number of trees less than 10 m in height and the number of trees with dbh of less than 20 cm and 20-50 cm. The results of this study highlighted the importance of habitat variables, especially snags, logs and old trees, for conserving and enhancing of birds especially cavity-nesting leading to conservation of the forest ecosystems.

Land cover changes and residential developments result in destruction of natural habitats and biodiversity. Land cover models are one of the most important methods to evaluate this trend. The objective of this study was comparison of Logistic Regression (LR) and Multi-Layer Perceptron Artificial Neural Networks (MLP ANNs) algorithms for transition potential modeling of coastal areas of Mazindaran province. Landsat satellite imageries, specifically 1988, 2001, 2006, and 2010 were used for change analysis. In addition, transition potential modeling was conducted using a logistic regression and multi layer perceptron artificial neural network. Each calibration period 2001–2006 was examined using Markov chain and hard prediction for extrapolating the year 2010. The accuracy assessment model was determined by kappa index. The results showed that logistic regression (0.8456) was more accurate than the multi layer perceptron artificial neural network (0.8276) in this study area.

Air pollution of cities is one of the most intricate environment al hazaeds that is a serious threat for health, hygiene and environment. Extensive studies show the potential effects of air pollution on human health, was including increased mortality, increased hospital treatments, especially changes in cardiopulmonary function- vascular. Particulate is one of six polluter that is very dangerous and have irreparable damage to the human body. This polluter are formed of substances such as acids, metals and dust.PM10 is one of the matter particulate which could cause severe air pollution. PM10 are known to particulate 10 microns and are formed from combination of nitrogen oxide and sulfur dioxide in the atmosphere. According to World Health Organization, Ahwaz with an annual average of 372 μg/m^3 of PM10 has acquired the most polluted city in first place in 1100 the city in the world. Therefore in this study with using data from the maximum pollution PM10 in series 24 hourly, were used for the to predict this polluter. A network with time delay and LMS learning algorithm is designed and were predicted the polluter concentrations for October 2011.

This study was performed in order to investigate socioeconomic status in affected areas of Hamoun international wetland. Firstly, the current status of region was studied by literature review, field survey and statistical analysis. Then strengths and weaknesses (internal factors) were identified as well as opportunities and threats (external factors) using Delphi Method. Results showed that the main social strengths and weaknesses are respectively young population and negative growth rate; also the significant social opportunities and threats are respectively existence of public universities and being in drug trade corridor. Furthermore, the main important economic S-W are respectively fertile soil for agricultural activities and long droughts, also the serious economic O-T are respectively young workforce and weak government economic policy in Sistan. Subsequently with integrating of internal and external factors ST, SO, WT and WO strategies were formulated which involve following important ones: to observe socioeconomic and cultural needs of Sistan in country policy making trends, to control drug and goods smuggling by education and participatory management, to provide water for agricultural activities, to announce Sistan as energy region by developing wind turbines, to decentralize health facilities from Zabol to other cities and to reopen the bored markets.