Reza Cyrus Sabri; Roya Azadeh Sabri
Volume 8, Issue 2 , January 2011
Abstract
The fast pace of development of Tehran (a capital city with a population of 12 million and grandiose ideas) over the last 30 years is the major cause of the deterioration of the natural environment and watershed. Stream corridors in the northern part of the city are the major areas for most of the wildlife ...
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The fast pace of development of Tehran (a capital city with a population of 12 million and grandiose ideas) over the last 30 years is the major cause of the deterioration of the natural environment and watershed. Stream corridors in the northern part of the city are the major areas for most of the wildlife diversity in Tehran and are easily affected by human intervention. The two major elements of the stream corridors are soil and water. If either of these is affected by human activities the ecosystem will become unhealthy and its natural balance will be unsettled. Therefore special consideration to environmental capacities is essential. This study was conceived on the basis of a phenomenological approach; an extensive literature review on the subject and the case study were also conducted. The research attempts to consider the Evin-Darakeh stream corridor as a green infrastructure by describing the benefits of green infrastructures. In order to reach this goal, planning principles for this stream corridor and the related strategies are explained.
Ebrahim Fataei,; Seied Masoud Monavari; Amir Hesam Hasani; Seied Ahmad Mirbagheri; Abdoreza Karbasi
Volume 8, Issue 2 , January 2011
Abstract
For assessment of water quality in Gharasou River, located in the Northwest of Iran, multivariate statistical analysis was used. During the period of one year, 18 physical, chemical and microbiological parameters were sampled in 11 sampling stations. The measured data were analyzed by a multivariate ...
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For assessment of water quality in Gharasou River, located in the Northwest of Iran, multivariate statistical analysis was used. During the period of one year, 18 physical, chemical and microbiological parameters were sampled in 11 sampling stations. The measured data were analyzed by a multivariate statistical approach, Cluster Analysis (CA). Based on CA analysis the stations were divided to three groups of highly polluted (HP), moderately polluted (MP), and less polluted (LP) stations. The results of the study revealed that multivariate statistical techniques are an effective statistical method for water quality assessment, identification of pollution sources/factors in water quality for effective water quality management. As Extracted clustered information can be used in reducing the number of sampling sites on the River without missing much information.
Mohammad Yazdi; Raana Esmailpur; Pedram Navi; Ahmad Khakzad
Volume 8, Issue 1 , October 2010
Abstract
Lavij coal deposit is situated at a distance of 48km to the southwest of Amol in the Central Alborz coalfield in the North of Iran. Lavij coal-bearing strata in the central Alborz zone are found within rocks of the Upper Triassic-Lower Jurassic era. The coal-bearing sediments in this area belong to the ...
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Lavij coal deposit is situated at a distance of 48km to the southwest of Amol in the Central Alborz coalfield in the North of Iran. Lavij coal-bearing strata in the central Alborz zone are found within rocks of the Upper Triassic-Lower Jurassic era. The coal-bearing sediments in this area belong to the Shemshak Formation (Upper Triassic-Lower Jurassic). This formation mainly consists of sandstone, shale, calcareous sandstone, argillite and siltstone. Several coal seams with different thicknesses are interbedded with sediments. The ecosystem, landscape and biodiversity of the area have all been affected by coal mining activities during the last few years. The environmental impacts of this mining can be studied from different viewpoints, but the research presented here concerns the geochemical environmental impacts. The surface and ground water of the Lavij area seem to have been polluted during the mining, natural erosion and dissolution of maceral and minerals of the coals of Lavij area. The present paper deals with geochemical environmental impacts of these coals and 14 samples were analyzed from surface and ground water of the Lavij area. The samples were analyzed by ICP-OES for As, Ba, Be, Cd, Co, Cr, Cu, Eu, Ga, Ge, La, Li, Mo, Pb, Mn, Zn, S, Nd, Ni, P, Sc, Sn, Sr, V, Y and Yb. Data processing showed the pollution in the water and soil of the area is very low.
Amirhesam Hassani; Fahime Ghanadi; Aghdas Rahimi
Volume 8, Issue 1 , October 2010
Abstract
Many environmental problems are caused by the irregular expansion of Tehran. The most important problems are due to petroleum installations to the south of the Tehran Aquifer, lack of due attention paid to environmental standards, produced by local petroleum companies. The aim of this study is the survey ...
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Many environmental problems are caused by the irregular expansion of Tehran. The most important problems are due to petroleum installations to the south of the Tehran Aquifer, lack of due attention paid to environmental standards, produced by local petroleum companies. The aim of this study is the survey of measure soluble petroleum in Tehran Oil Refinery groundwater. The area of investigation comprises Rey industrial zone with 900 hectares where its drinking water is provided by seven qanats, deep and handy wells, and the Jajrood, Karaj and Kan Rivers. The annual average temperature, rainfall and evaporation are 17 ̊C, 200 mm and 2500 mm, respectively. Hence, sampling from 8 water wells and analysis of the samples were carried out during the summer and winter of 2008-2009. Finally, the results were shown in some figures and compared with national standards. The results of analysis for parameters (such as BOD, COD, oil and grease, phenol, TPHs, aromatic and aliphatic hydrocarbons) are as below: COD(10-55000 mg/L), BOD (1-30555 mg/L), phenol (0.01-0.08 mg/L), oil and grease (5-130 mg/L), TPHs (0.05-25.5 mg/L), aliphatic hydrocarbons (1.7- 0.001 mg/L) ad, aromatic hydrocarbons (0.034-2.13 mg/L). Results show that the quantity of oil pollutants in stations 4 (Bagher Abad), 5 (Esmail Abad) and 3 (Azim Abad) is high compared with the other stations. In other words, the quantity of oil pollutants in Dorsun Abad , Esmail Abad and Azim Abad villages is more than in Kheir Abad, Bagher Abad, Shahr Sang and the western side of Tehran Oil Refinery Company. Also, the concentration of oil pollutants in the winter compared to spring is very high. As a consequence of this investigation, it is obvious that the quality of major water sources is not suitable for drinking or agriculture consumption. In addition, the wastewater produced by Tehran Oil Refinery Company, spills from Tehran’s domestic wastewater channel and leakage from underground oil transfer lines are the most important of sources of pollution in local groundwater resources.
Ahmad Farrokhian Firouzi; Mehdi Homaee; Morteza Sattari
Volume 8, Issue 1 , October 2010
Abstract
Bacteria attachment to soil is an important component in bacteria transport models. The objective of this study was to quantify the influence of calcium carbonate on bacteria attachment and detachment in calcareous soil. Consequently, 60 calcareous soil samples were collected from Central Province and ...
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Bacteria attachment to soil is an important component in bacteria transport models. The objective of this study was to quantify the influence of calcium carbonate on bacteria attachment and detachment in calcareous soil. Consequently, 60 calcareous soil samples were collected from Central Province and their bacteria (Escherichia coli) adsorption isotherm, physical and chemical properties were measured. Three types of adsorption isotherms were evaluated. The results indicated that linear isotherm leads to a better prediction of bacteria attachment to calcareous soil in comparison with the Freundlich and Langmuir isotherms. A pedotransfer function was also derived to predict the kdparameter of the linear isotherm from soil particle size distribution and calcium carbonate content. The attachment and detachment of bacteria in three treatments of calcium carbonate content (10, 21 and 37%) were tested in a completely randomized design (CRD) with three replications. According to the results, increasing soil calcium carbonate content leads to enhanced equilibrium and kinetic bacteria attachment (p<0.05). Bacteria detachment also decreases by increasing soil calcium carbonate (p<0.05).
Fatemeh Shayan Pooya; Fereydoon Abbasi Davani; Mohammad Sadegh Naseri
Volume 8, Issue 1 , October 2010
Abstract
The sampling process in alpha spectroscopy for measuring the activity and concentration of uranium isotopes is a very sensitive one due to the short range of alpha particles in special compounds of uranium in soil and the close energy peaksof the alpha particles emitted from its isotopes. In this research, ...
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The sampling process in alpha spectroscopy for measuring the activity and concentration of uranium isotopes is a very sensitive one due to the short range of alpha particles in special compounds of uranium in soil and the close energy peaksof the alpha particles emitted from its isotopes. In this research, the effect of certain parameters such as the quality of acid dissolution, the presence of a tracer in the sample, pH, electro deposition, spectroscopic electronics and so on were investigated in sampling and spectroscopy, according to ASTM. The average yield of (64.4±15.7) % was achieved after eight times of sampling by incorporating IAEA, ASTM and Talvite electro deposition methods. A BU-014-300-500 PIPS detector was utilized in this study.
Rasul Ghorbani; Ahad Ebrahimpour Lanbaran
Volume 8, Issue 1 , October 2010
Abstract
Most recreation areas in Iran been constructed on the basis of the fabric principle with less attention paid to the mental and behavioral needs of users, in spite of increasing demand for such facilities. In this paper we attempt to analyze the motivation of users with by employing seeking-escaping and ...
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Most recreation areas in Iran been constructed on the basis of the fabric principle with less attention paid to the mental and behavioral needs of users, in spite of increasing demand for such facilities. In this paper we attempt to analyze the motivation of users with by employing seeking-escaping and Pull and Push theory. At first, we survey people’s main motivation for using the natural and man-made attractions of Oun-Ebn-Ali recreation center, based on seeking-escaping theory and then, as a final reward to the users, the relationship between their perceptions and improved indices of the quality of place were evaluated. The results show that the users go to Oun-Ebn-Ali to escape from pressures of everyday life and achieve peace through observing nature, doing sport and meeting friends. Although some undesirable factors such as a shortage of trees for shade and street furniture, congestion and unsuitable accessibility have adversely affected the process of developing recreation place uses and restricted the number of users. According to the results, improving the natural attractions and recreational furniture, better accessibility and distribution of furniture around different parts of the site have increased the desirability of using Oun-Ebn-Ali recreation place.
Seyed Nouroddin Amiri; Jila Sajadi; Seyed Hassan Sadough Vanini
Volume 8, Issue 1 , October 2010
Abstract
Changes in the detection of the mangrove area in Niband Bay adjacent to the South Pars industrial complexes by satellite imaging over different time periods can be a suitable indictor for assessment of possible environmental damage caused by the extensive activities of the aforementioned industry. Environmental ...
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Changes in the detection of the mangrove area in Niband Bay adjacent to the South Pars industrial complexes by satellite imaging over different time periods can be a suitable indictor for assessment of possible environmental damage caused by the extensive activities of the aforementioned industry. Environmental damage from industrial activities, particularly with regard to the oil industry, has been inevitable ever since the industrial revolution. The importance of damage which often undermines the positive economic impacts of these industries has drawn attention to the use of different effective techniques for reducing the damage, such as analyzing satellite data since the 1960s. Hence, this paper attempts to investigate the mangrove area by using IRS data (in 2008) and analyzing them with ILWIS package. For this purpose, multi-bands color images 2, 3, 4 have been used for mapping the mangroves and identifying their location. GPS is used for ground veracity. The aim of this research is to consider the application of satellite data (IRS) along with the vegetation index for assessing the mangrove areas and for measuring the possible environmental damage caused by the above mentioned industry. The results show the application of vegetation indices, particularly those in IRS4/IIRS3, within the other four indices used for mapping the mangrove in this research. Mangrove areas measured in this research show considerable differences in comparison with those found in previous research studies.
Mehdi Ghadimi; Seyed Mohsen Hosseini; Hamid-Reza Pourghasemi; Hamid-Reza Moradi
Volume 8, Issue 1 , October 2010
Abstract
Zoning in the management area of protected areas through the resolution of conflicts has decreased protected areas and necessary measures will need to be provided. The study area of this research was chosen with the aim of modeling and zoning Manesht and Ghalarang protected area with an area of 33000 ...
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Zoning in the management area of protected areas through the resolution of conflicts has decreased protected areas and necessary measures will need to be provided. The study area of this research was chosen with the aim of modeling and zoning Manesht and Ghalarang protected area with an area of 33000 ha in Ilam Province. In order to obtain the optimal protection model, fuzzy logic has been employed. For this purpose, field studies to identify and collect information were initially conducted. All the factors that have an effective role in protecting were collected and then analyzed using an analytical hierarchical process and the priority factors were classified. This study showed that the characteristics of slope, soil, geology, vegetation, erosion, land use and distance from the channel or river are related to the highest weight assigned to and therefore the main factor in effective protection in the region. These data were saved in the raster and vector format in ILWIS software and analysis based on Fuzzy set theory was used. Fuzzy analysis using the IDRISI software was made to determine the values and membership functions. In this study, different fuzzy operators such as Sum, Product and Gamma were used. The results showed that the fuzzy gamma operator with 975.0=l provided the highest value of modeling accuracy of the study area protection.
Hamze Noor; Seyed Khalagh Mirnia; Mohammad Bagher Raisi
Volume 8, Issue 1 , October 2010
Abstract
The aim of the present study was to predict organic matter (OM) loss in Kojor Watershed which is a hyrcanian ecosystem. For this purpose, discharges, suspended sediment (SS) and OM loss resulting from storm events were sampled at one fixed point of the river using a manual sampler. Results showed that ...
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The aim of the present study was to predict organic matter (OM) loss in Kojor Watershed which is a hyrcanian ecosystem. For this purpose, discharges, suspended sediment (SS) and OM loss resulting from storm events were sampled at one fixed point of the river using a manual sampler. Results showed that soil erosion rate during the sampling period were dramatically affected by the loss of OM. Also, the results of modeling among OM loss, SS and discharge indicate that OM loss was not estimated by the discharge, while SS can estimate the loss of OM with a determination coefficient and estimation error of of 95% and 24%, respectively. These results could facilitate the application of methods obtained in the present study to other areas with similar conditions.
Hossein Kermanian; Zahra Razmpour; Omid Ramezani; Mehdi Rahmaninia
Volume 8, Issue 1 , October 2010
Abstract
A close relationship exists between forest product industries and the water cycle. Water as a natural resource is assumed to be a necessary and vital element in pulp and paper manufacturing as well as power generation in the related power plants. The objective of the current study is to determine the ...
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A close relationship exists between forest product industries and the water cycle. Water as a natural resource is assumed to be a necessary and vital element in pulp and paper manufacturing as well as power generation in the related power plants. The objective of the current study is to determine the main factors affecting water consumption in recycled paper manufacturing companies using the analytical hierarchy process (AHP). Several questionnaires and related tables were forwarded to selected recycled paper manufacturing companies to evaluate the water reduction criteria in different sectors including the manufacturing process, final product, raw material, human resources, costs and expenditures, environmental regulations and technical modifications. The results were analyzed using Expert Choice 2000 software. The results indicated that the final product criterion was ranked first followed by manufacturing process, human resources, costs and expenditures, environmental regulations and technical modifications, in that order. Also among alternatives, final product, cooling water network, and water storage tanks were categorized in the first three priorities. The specified priorities would assist managers and production experts to achieve optimal water consumption with the minimum possible cost.
Yahya Kooch; Seyed Mohsen Hosseini; Hamid Jalilvand; Asghar Fallah
Volume 8, Issue 1 , October 2010
Abstract
Nowadays, the need for sustainable resource management has led to introducing new methods for classification of managed resources. The importance of biodiversity and its management and considering to new methods for determining management units introduced the initial idea for this research. For this ...
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Nowadays, the need for sustainable resource management has led to introducing new methods for classification of managed resources. The importance of biodiversity and its management and considering to new methods for determining management units introduced the initial idea for this research. For this study of biodiversity in lowland forests of Khanikan located in Chalous, environmental units were initially determined by Two-way Indicator Species Analysis. The study area was classified into five different environmental units. For analyses of the diversity, richness and evenness of the environmental units, the Simpson, Margalef and Hill indices were used. For investigation of soil characteristics, four soil profiles were taken at different depths of the profiles (0-10, 10- 20, and 20 -30cm) for each environmental unit and conveyed to the laboratory. Some soil characteristics were analyzed in the laboratory. Factor analysis is a statistical technique for producing a foundation algorithm or specific model for determination of the complex relationship among variables. To identify the relationships within biodiversity, different indices with soil physic-chemical and biological characteristics were studied by principal component analysis (PCA). The location of soil variables on the axes indicates that nitrogen at the third depth, cation exchangeable capacity of the first and third depths, available phosphorous at all depths are settled on axis 1. The settling location all the biodiversity indices was also in the direction of axis 1. The left orientation of axis 1 was devoted to Simpson diversity, Margalef richness, and Hill evenness indices. Thus, each of the biodiversity indices had a direct relationship with soil characteristics in the left orientation of axis 1. Available phosphorous was introduced as the most effective factor on biodiversity indices.
Ozeair Abessi; Mohsen Saeedi
Volume 8, Issue 1 , October 2010
Abstract
Due to the location of a domestic, industrial and agricultural zone near the Caspian Sea, this water body has long been under pressure and environmental threat. As a result of development of oil production activities in Caspian region, such as oil exploration and extraction in the central and eastern ...
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Due to the location of a domestic, industrial and agricultural zone near the Caspian Sea, this water body has long been under pressure and environmental threat. As a result of development of oil production activities in Caspian region, such as oil exploration and extraction in the central and eastern part, a large volume of oil related pollutants is released annually into this important water body. Considering the fact that hydrocarbons may cause adverse impacts on the aquatic and marginal life, the monitoring of sediment as hydrocarbons in the sea has long been considered. In this paper, oil contamination of surface sediments in large areas of the Mazandran and Golestan coasts (southeastern Caspian) are investigated in detail. In this study, using different concentrations of hydrocarbon components and developing related ratios and indices, the biodegradation and weathering extent of oil residues in the bottom sediments of the southern and southeastern Caspian Sea were appraised. The general concentration of the total petroleum hydrocarbon (TPH), normal Alkanes (n-Alkanes) and polycyclic aromatic hydrocarbons (PAHs) in the study area shows the relatively clean condition of sediments in the western part of the sea and moderate contamination in the central and eastern parts. Indices developed also corroborate the presence of degraded oil residue, high relative biodegradation and a degree of weathering of hydrocarbons in the surface sediment of the area, which suggest a chronic input of oil-related hydrocarbons in the neighbourhood of the study region.
Morteza Davodi; Abbas Esmaili-Sari; Nader Bahramifar; Seyed Mahmoud Ghasempouri
Volume 8, Issue 1 , October 2010
Abstract
Shadegan wetland, one of the largest wetlands in Iran, is subject to different pollutants. One of these contaminants is the residue of organochlorine pesticides such as DDT and its metabolites used to combat pests. Residues of DDT and its metabolites (p,p/-DDT,o,p/-DDT,p,p/-DDE, o,p/-DDE, p,p/-DDD) were ...
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Shadegan wetland, one of the largest wetlands in Iran, is subject to different pollutants. One of these contaminants is the residue of organochlorine pesticides such as DDT and its metabolites used to combat pests. Residues of DDT and its metabolites (p,p/-DDT,o,p/-DDT,p,p/-DDE, o,p/-DDE, p,p/-DDD) were investigated in five edible fish species of Shadegan wetland, and the effect of the amount of this pesticide on the weight, age and diet was investigated. Total DDT (the sum of 5 metabolites) in Barbus grypus and Cyprino carpiowas 6.50 and 3.27 ng g-1, respectively. Results showed that p,p/-DDE had a maximum concentration in all species and p,p/-DDT in Barbus sharpeyi (0.12 ng g-1) and Cyprino carpio(0.09 ng g-1), o,p/-DDE metabolite in Barbus grypus ( 0.12 ng g-1) and Aspius vorax (0.20 ng g-1) and o,p/-DDT metabolite in Barbus barbules had a minimum concentration. These results show any new application of this pesticide in the land around the wetland. The mean concentration of DDTs was higher in weight group>320 g (6.77 ng g-1) and in age group>3 years (6.70 ng g-1) and those of an omnivorous diet (7.34 ng g-1) than in the other groups. The calculation ofestimated daily intake (EDI) of this pesticide and comparison with international standards, showed no risks for residents in this area.
Volume 8, Issue 1 , October 2010
Morteza Molaei; Mohammad Kavoosi Kelashemi; Hamed Rafiee
Volume 8, Issue 1 , October 2010
Abstract
More than half of the Greenhouse Effect is from carbon dioxide emissions. Emissions of carbon dioxide cause undesirable climatic and environmental effects and, finally, affect the global economy. Because of the importance of determining the economic impacts of increasing CO2 emissions, this study investigates ...
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More than half of the Greenhouse Effect is from carbon dioxide emissions. Emissions of carbon dioxide cause undesirable climatic and environmental effects and, finally, affect the global economy. Because of the importance of determining the economic impacts of increasing CO2 emissions, this study investigates the cointegration relationship between per capita Gross Domestic Production (GDP) and per capita CO2 emissions during 1974-2004 and also tests the existence of an Environmental Kuznets Curve for Carbon Dioxide during this period. The Auto Regressive Distributed Lag (ARDL) method and Error Correction Model (ECM) were used to study the cointegration relationship. Results indicated that in both short- and long-term period, a significant relationship exists between variables. On the other hand, the coefficient of error correction term was -0.19 and statistically significant. According to the results of the differential models between per capita GDP and per capita CO2 emission, Environmental Kuznets Curve for CO2 exists during this period. Keywords: Cointegration, ARDL, ECM, Environmental CO2, Kuznets Curve, Iran.
Seyed Ali Jozi; Sahar Rezaian; Mahdi Irankhahi; Nabiollah Moradi
Volume 7, Issue 4 , July 2010
Abstract
This research was performed with the aim of providing a quantitative strategic plan for ecotourism development in Mond Protected Area, Booshehr Province. Therefore, as a first step, Mond Protected Area’s zones were identified using the Multi Criteria Evaluation (MCE) method and valuation and analysis ...
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This research was performed with the aim of providing a quantitative strategic plan for ecotourism development in Mond Protected Area, Booshehr Province. Therefore, as a first step, Mond Protected Area’s zones were identified using the Multi Criteria Evaluation (MCE) method and valuation and analysis of the region’s ecotourism demand index was performed through completing Clawson questionnaires in the form of Travel Cost Method (TCM). Results of this investigation showed that the forecasted outdoor recreational value of Mond Protected Area was equal to 5,698,250,000 Rials per month during the period of study. For the purpose of collection and presentation of quantitative strategies for ecotourism development in Mond Protected Area, we used the Freeman strategic planning matrix method known as the “interested party matrix”. To this purpose, internal factors (Strengths and Weaknesses) and external factors (Opportunities and Threats) in study area were identified and evaluated. Finally, the Freeman matrix was completed on the basis of economic, social, cultural and ecological priorities in the study area and by loading each development alternatives, three strategies were recommended of which the strategy “attraction of investment in private sector via giving bank facilities with long term return period, with +77 score” is in the position of high important strategy of ecotourism development in study area.
Hossein Sabahi; Mohamad Faizi; Hadi Viesi; Kamal Sadate Asilan
Volume 7, Issue 4 , July 2010
Abstract
Sikan River is one of the end branches flowing from Saymareh River. 57% of agricultural land in Dareshaher are located in the environs of this river. In view of the consumption of 1343 tons of chemical fertilizers per year, the effluents from this land can influence the quality of river water. With a ...
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Sikan River is one of the end branches flowing from Saymareh River. 57% of agricultural land in Dareshaher are located in the environs of this river. In view of the consumption of 1343 tons of chemical fertilizers per year, the effluents from this land can influence the quality of river water. With a view to providing basic management strategies, the seasonal variations in water quality were evaluated. In this way, the quality characteristics of river water which may be influenced by wastewater, was measured in four seasons throughout the year. The NH3ranged from 0.53 to 0.55 mg/lit in spring-summer and 0.19-0.26 mg/lit in autumn-winter which is higher than the drinking water guidelines value for spring-summer, namely <0.3. The nitrate content was within the permissible range for potable water, and varied from 3.7 to 7.3 mg/lit in autumn and summer, respectively. The levels of phosphate in the river varied between 0.007 and 0.032 mg PO4 as P/lit in winter and summer, respectively, which is the standard level for P in water system to prevent eutrophication-related problems, i.e. <0.035 mgP/lit. The sulfate concentration was higher than the recommendation standard of 250 mg/lit in autumn. DO and COD levels were completely acceptable. In sum, the related agricultural activities justify the relative increase of mentioned parameter in summer.
Taghi Tavousi; Mahmood Khosravi; Khaled Ghaderi Zeh
Volume 7, Issue 4 , July 2010
Abstract
The purpose of this study is to identify the occurrence of drought events and short-term dry periods in Iranshahr region. The standardized precipitation values are applied for detecting drought in Iranshahr region for the period of 1980-2006. For recognition of short duration dry periods, a Markov chain ...
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The purpose of this study is to identify the occurrence of drought events and short-term dry periods in Iranshahr region. The standardized precipitation values are applied for detecting drought in Iranshahr region for the period of 1980-2006. For recognition of short duration dry periods, a Markov chain model was used. The daily data were classified into two groups; wet days (precipitation equal or more than 0.1mm) and dry days (precipitation less than 0.1mm). The frequency of wet and dry periods and the probabilities of the duration of each wet and dry period and its return periods were calculated. The analysis of droughts has shown that the frequency of drought periods in the initial years of statistical period is fewer and that they have less regularity. After 1998, not only the drought frequency but also its intensity and duration is increased. The probability of two successive wet or dry days, the differences of simple and climatic probabilities of wet and dry days was determined. The results showing that significant differences do not exist between simple and climatic probabilities of wet and dry short duration periods. The frequency of dry days is observed in all months. The monthly average of dry duration is 25 or more days.
Narjes Abdolmanafi; Mohammad Mousavi-Baygi
Volume 7, Issue 4 , July 2010
Abstract
Most air pollutant dispersion models are analytical models that do not consider the spatial variation of wind velocity and diffusivity coefficient. To obtain an analytical model by considering the spatial variation of wind velocity and diffusivity coefficient, some simplifying assumptions must be made; ...
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Most air pollutant dispersion models are analytical models that do not consider the spatial variation of wind velocity and diffusivity coefficient. To obtain an analytical model by considering the spatial variation of wind velocity and diffusivity coefficient, some simplifying assumptions must be made; in addition, the analytical solution is more complicated and less accurate. In this study, by solving the advection-dispersion equation for a steady and elevated pollutant stack, the spatial variation of the wind velocity and diffusivity coefficient is considered and the 2-dimensional distribution of the pollutant concentration is calculated. The model could be applied for both stable and unstable conditions. The advection-dispersion equation has been solved using the finite difference method. The proposed model has been validated using other researcher's experiments data and existing analytical models. The results show a good level of accuracy for the model.
Mohsen Ebrahimi Khusfi; Roshanak Darvishzade; Aliakbar Matkan; Davood Ashourloo
Volume 7, Issue 4 , July 2010
Abstract
Since soil moisture and vegetation cover are the most important parameters effecting drought, analyses of the vegetation fraction and soil spectral signature, especially in the red and infra red bands, are essential in drought estimation. In this study, the Perpendicular Drought Index (PDI), Modified ...
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Since soil moisture and vegetation cover are the most important parameters effecting drought, analyses of the vegetation fraction and soil spectral signature, especially in the red and infra red bands, are essential in drought estimation. In this study, the Perpendicular Drought Index (PDI), Modified Perpendicular Drought Index (MPDI) and Vegetation Supply Water Index (VSWI) have been used for drought assessment in arid regions in Central Iran during a time interval of four years (1999-2002). To do this, ETM+ images of LANDSAT 7 for the years 1999 and 2002 and the rainfall statistics for 23 years have been used. Analysis of vegetation cover using vegetation indices demonstrated that in arid regions, changes in vegetation cover were best mapped using a SAVI2 index. The results of MPDI indicated that drought has increased in the rangelands of the study area because of a decrease in seeding of the rangeland and vegetation fraction. PDI showed that the severity of the drought has decreased due to an increase in rainfall in 2002.
Farzad Jalilian; Yaghoub Fathipour; Ali Asghar Talebi; Amin Sedaratian
Volume 7, Issue 4 , July 2010
Abstract
In addition to the abundance and population fluctuation of the common species, the fauna of syrphid flies of the northern parts of Ilam Province were studied during the period 2003-2004. In total, 30 species of syrphids including 21 predatory species, 8 saprophages species and one phytophagus species ...
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In addition to the abundance and population fluctuation of the common species, the fauna of syrphid flies of the northern parts of Ilam Province were studied during the period 2003-2004. In total, 30 species of syrphids including 21 predatory species, 8 saprophages species and one phytophagus species were identified. All species are first records from Ilam Province. The results of population abundance obtained from Malaise traps during 2004 indicated that Episyrphus balteatus (De Geer), Eupeodes corollae (Fabricius) and Scaeva albomaculata (Macquart) are among the most frequently occurring species and also important predators of aphids in this region. The population fluctuation of these three species showed that the highest population levels of adults occur in early spring.
Mohammad Hosein Sharifzadegan; Saied Amir Razavi Dehkordi
Volume 7, Issue 4 , July 2010
Abstract
Attempts to prepare a national spatial plan over the previous 35 years have always met problems and challenges. Experience of spatial planning in Iran (often at national level) has encountered events and decision taking through concepts, theories, techniques, producers, processes, organizations and logic ...
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Attempts to prepare a national spatial plan over the previous 35 years have always met problems and challenges. Experience of spatial planning in Iran (often at national level) has encountered events and decision taking through concepts, theories, techniques, producers, processes, organizations and logic that have sometimes led to improvement in this work and at other times deviated it from its correct path. This research aims to analyse and evaluate spatial planning through a process of planning point of view and, in this way, focuses on concepts, organizations and current rules in Iran’s planning system to understand some of present challenges and make recommendation for confronting them. According to the research outcomes, major reasons for the failure of Iran’s spatial plans are found in the conceptual, organizational and logical contexts. It is therefore not expected that spatial planning recommendations would be operational, because of incorrect presumptions and poor recognition that surround the spatial planning issue as well as some independent and obligatory rules, unstable and imprecise organizational arrangements, and the existence of a dominant sectorial view of long-term economic development planning.
Azam Namdari; Nematollah Jaafarzadeh Haghighifard; Faramarz Tarkian; Zabihollah Mazarei
Volume 7, Issue 4 , July 2010
Abstract
This study focuses on the identification, classification and encoding of hazardous generational wastes aimed at running a comprehensive waste management, on an RCRA basis, in the greatest Middle East oil unit at Ahvaz Karun Oil and Gas production unit no.02. To achieve such a purpose, a 154-test questionnaire ...
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This study focuses on the identification, classification and encoding of hazardous generational wastes aimed at running a comprehensive waste management, on an RCRA basis, in the greatest Middle East oil unit at Ahvaz Karun Oil and Gas production unit no.02. To achieve such a purpose, a 154-test questionnaire analysis, drawings of units, standard experiments, comparison of the chemicals found in the wastes with 8 lists of hazardous materials available in standard international checklists and determination of the number of materials available per checklist have been put into practice. The results of this research undertaken for the first time in Iran, reveals that: 33 kinds of toxic hazardous wastes, five kinds of non-hazardous materials and 25 types of as yet unproven wastes were detected; among these, 3 kinds of them were placed in acute hazardous wastes, four in toxic hazardous wastes, 4 in hazardous wastes from definite sources, 8 in priority toxic materials, 6 on the US Environmental Protection Agency (EPA) checklist and 10 in the toxic TCLP toxic checklist. Six heavy metals, namely nickel, lead, zinc, copper, chromium and cadmium, are categorized as toxic materials. Finally, waste water centrifugation was recommended to prevent the factory offshore soil becoming polluted with hazardous materials and bioremediation to purify the contaminated soils; the final waste management for each group of hazardous and non-hazardous wastes was determined.
Eskandar Zand; Mohammad Ali Baghestani,; Mohammad Reza Labafi Hosinabadi,; Ali Reza Atri; Mahdi Minbashi Moeini
Volume 7, Issue 4 , July 2010
Abstract
Experiments were conducted to investigate herbicide resistance in wild oat, canary grass, rye grass, and barnyard grass that were collected from Khuzestan, Fars, Markazi, Golestan, Kermanshah, Azarbayjan, Gilan and Mazandaran Provinces during 2004 to 2008. From among 333 collected weed biotypes collected, ...
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Experiments were conducted to investigate herbicide resistance in wild oat, canary grass, rye grass, and barnyard grass that were collected from Khuzestan, Fars, Markazi, Golestan, Kermanshah, Azarbayjan, Gilan and Mazandaran Provinces during 2004 to 2008. From among 333 collected weed biotypes collected, 319 weed biotypes were suspected to be resistant to and 14 to be susceptible to herbicides. It was found that 182 wild oat biotypes, 61 canary grass biotypes and 14 ryegrasses out of the collected biotypes showed resistance to acetyl-CoA carboxylase inhibiting herbicides (including Clodinafop-propargyl, fenoxaprop P ethyl and Diclofop methyl) and 76 weed biotypes showed suspected resistance or resistance to Propanil, Butachlor, Molinate and Thiobenkarb herbicides. The results indicated that 82 biotypes out of 333 biotypes (26%) collected from 92 fields (525 ha) showed resistance, 99 biotypes (30%) collected from 86 fields (625 ha) were tolerant and 152 biotypes (46%) collected from 68 fields (498 ha) did not show any herbicide resistance. Based on the number of resistant samples, the fields or field area was 298%, 283% and 203% respectively in 2008 as compared to 2005. It is incontrovertible that the number of infested fields to resistant weed biotypes is increasing and serious intensification was reported in the cases of wild oat, canary grass and rye grass, respectively. It was also reported that the maximum frequency, area and the number of infested fields to resistant wild oat was detected in Khuzestan, Kermanshah, Fars, Golestan and Ilam Provinces. The maximum frequency, area and the number of infested fields to resistant canary grass was found in Khuzestan, Golestan and Fars Provinces.
