دانشگاه تهرانJournal of Environmental Studies1025-8620365320100522Prediction of River Water Quality by Adaptive Neuro Fuzzy Inference System (ANFIS)Prediction of River Water Quality by Adaptive Neuro Fuzzy Inference System (ANFIS)21480FAHamid RezaSafaviJournal Article19700101Limitations on freshwater resources have caused water resources managers to focus an increasing attention over the past few decades on water quality protection. Surface water quality management in such resources as rivers, seas, lakes, and estuaries is of a greater importance than other water resources and a greater number of studies have been conducted on them as they are more accessible and, therefore, more directly exposed to a variety of contaminants and pollutants. Application of appropriate and efficient mathematical models for river water quality simulation is essential for the formulation of comprehensive guidelines used in evaluating measures that are employed for river pollution control and management. The non-linear equations dominating pollutant transfer phenomena in rivers, the complexity of their simultaneous solution, and the multiplicity of kinetic constants and coefficients have made it difficult, or at times impossible, to use physically-based models and methods for this purpose. Therefore, most of these models can only be applied to simplified cases or to situations where the models are strictly calibrated and validated, with no adequate accuracy when applied to unrestricted conditions. The uncertainties in water quality problems have made fuzzy inference systems, especially as combined with adaptive neural networks, to be used as a novel approach. The main objective of the present study is to exploit the capabilities of the adaptive neuro-fuzzy inference system (ANFIS) for river quality predictions with emphasis on DO and BOD. In the case study carried out on the Zayandehroud River, BOD predictions were obtained by the proposed system with a correlation coefficient of 0.953 in the calibration stage and 0.931 in the validation stage and DO predictions were obtained with a correlation coefficient of 0.921 in the calibration stage and 0.904 in the validation stage. Comparison of the results reveals the high accuracy level of the proposed model.Limitations on freshwater resources have caused water resources managers to focus an increasing attention over the past few decades on water quality protection. Surface water quality management in such resources as rivers, seas, lakes, and estuaries is of a greater importance than other water resources and a greater number of studies have been conducted on them as they are more accessible and, therefore, more directly exposed to a variety of contaminants and pollutants. Application of appropriate and efficient mathematical models for river water quality simulation is essential for the formulation of comprehensive guidelines used in evaluating measures that are employed for river pollution control and management. The non-linear equations dominating pollutant transfer phenomena in rivers, the complexity of their simultaneous solution, and the multiplicity of kinetic constants and coefficients have made it difficult, or at times impossible, to use physically-based models and methods for this purpose. Therefore, most of these models can only be applied to simplified cases or to situations where the models are strictly calibrated and validated, with no adequate accuracy when applied to unrestricted conditions. The uncertainties in water quality problems have made fuzzy inference systems, especially as combined with adaptive neural networks, to be used as a novel approach. The main objective of the present study is to exploit the capabilities of the adaptive neuro-fuzzy inference system (ANFIS) for river quality predictions with emphasis on DO and BOD. In the case study carried out on the Zayandehroud River, BOD predictions were obtained by the proposed system with a correlation coefficient of 0.953 in the calibration stage and 0.931 in the validation stage and DO predictions were obtained with a correlation coefficient of 0.921 in the calibration stage and 0.904 in the validation stage. Comparison of the results reveals the high accuracy level of the proposed model.دانشگاه تهرانJournal of Environmental Studies1025-8620365320100522Chemical Partitioning & Pollution Intensity of Heavy Metals in Siahrud River SedimentChemical Partitioning & Pollution Intensity of Heavy Metals in Siahrud River Sediment21481FAAbdolrezaKarbassiGholamrezaNabi Bidhendi0000-0001-9930-9080FereydounGhazbanShokohKokabi HabibzadehJournal Article19700101In the recent years, sediments are used for the assessment of pollution. Since sediments have been in contact for a long time with over lying water, therefore they have been able to adsorb pollution on to their surface. In the present investigation, the surficial sediments of Siahrud River have been analyzed. The loose, sulphide and organic bonds of metals with various sedimentary phases has been assessed by chemical partitioning technique. The sum of these three bonds is indicative of anthropogenic source of metals into the river. The lithogenic portion of metals were obtained by a two step chemical partitioning technique. The anthropogenic portion of metal contents in river sediments shows the following pattern:
Pb(85%)>Zn(84%)>Cd(62%)>As(47%)>Mn(35%)>Ni(34%)>Cu(21%)
The inter-relationship amongst various metal bonds were assessed by cluster analysis. The results show that bio-availability of metals such as Cd, Zn and As are highly dependent on anthropogenic portion and specially loosely bonded ions of such metals. The over all pollution intensity was obtained by various pollution intensity indices. The pollution intensity of Zn and Pb in the sediments of Siahrud River are 3.572 and 3.148, respectively that are indicative of high pollution intensity. Other studied metals fall within “no pollution” to “low pollution” intensities.In the recent years, sediments are used for the assessment of pollution. Since sediments have been in contact for a long time with over lying water, therefore they have been able to adsorb pollution on to their surface. In the present investigation, the surficial sediments of Siahrud River have been analyzed. The loose, sulphide and organic bonds of metals with various sedimentary phases has been assessed by chemical partitioning technique. The sum of these three bonds is indicative of anthropogenic source of metals into the river. The lithogenic portion of metals were obtained by a two step chemical partitioning technique. The anthropogenic portion of metal contents in river sediments shows the following pattern:
Pb(85%)>Zn(84%)>Cd(62%)>As(47%)>Mn(35%)>Ni(34%)>Cu(21%)
The inter-relationship amongst various metal bonds were assessed by cluster analysis. The results show that bio-availability of metals such as Cd, Zn and As are highly dependent on anthropogenic portion and specially loosely bonded ions of such metals. The over all pollution intensity was obtained by various pollution intensity indices. The pollution intensity of Zn and Pb in the sediments of Siahrud River are 3.572 and 3.148, respectively that are indicative of high pollution intensity. Other studied metals fall within “no pollution” to “low pollution” intensities.دانشگاه تهرانJournal of Environmental Studies1025-8620365320100522Assessment of Heavy Metal and oil pollution of sediments of South Eastern Caspian sea using IndicesAssessment of Heavy Metal and oil pollution of sediments of South Eastern Caspian sea using Indices21482FAMohsenSaaediOzeirAbessiAhmadJamshidiJournal Article19700101Caspian Sea as the biggest surrounded water body in the word has long been in the pressure from environmental standpoints due to the fact that its large is surrounding by the larg domestic, industrial and agricultural areas. Concern to inverse impacts of the inputted pollutants on the aquatic organism and margin human societies’ health, quality monitoring of the sediment as the main fate of the pollutants in water bodies has long been considered. In the current study large area in the coastal areas of Mazandran and Gholestan province has been investigated with a view to their general pollution to petroleum hydrocarbons and heavy metals. Observed concentrations of the heavy metals in the fine sediment show high but non-polluted concentration of Ni (35-67 ), Cu (15-50 ), Zn (56-104 ), V (90-140 ) and Cr (60-92 ) in the coast of Mazandran and Gholestan area and low to moderate pollution of the sediment to Sn (3-4 ) and Pb (22-25 ) in west and center parts of the study area. Concentrations in the samples show variation of polycyclic Aromatic hydrocarbon (PAH) concentration in 150-1600 which accumulates more in Sari and Chaloss coast to the extent of moderate pollution of the region. Obtained results in this study also point the proportional contamination of the sediment to Total Petroleum hydrocarbon (TPA) in neighbor of Tonekabon and Mahmood Abad.Caspian Sea as the biggest surrounded water body in the word has long been in the pressure from environmental standpoints due to the fact that its large is surrounding by the larg domestic, industrial and agricultural areas. Concern to inverse impacts of the inputted pollutants on the aquatic organism and margin human societies’ health, quality monitoring of the sediment as the main fate of the pollutants in water bodies has long been considered. In the current study large area in the coastal areas of Mazandran and Gholestan province has been investigated with a view to their general pollution to petroleum hydrocarbons and heavy metals. Observed concentrations of the heavy metals in the fine sediment show high but non-polluted concentration of Ni (35-67 ), Cu (15-50 ), Zn (56-104 ), V (90-140 ) and Cr (60-92 ) in the coast of Mazandran and Gholestan area and low to moderate pollution of the sediment to Sn (3-4 ) and Pb (22-25 ) in west and center parts of the study area. Concentrations in the samples show variation of polycyclic Aromatic hydrocarbon (PAH) concentration in 150-1600 which accumulates more in Sari and Chaloss coast to the extent of moderate pollution of the region. Obtained results in this study also point the proportional contamination of the sediment to Total Petroleum hydrocarbon (TPA) in neighbor of Tonekabon and Mahmood Abad.دانشگاه تهرانJournal of Environmental Studies1025-8620365320100522Evaluation of THMs Concentration in Tehran’s Drinking Water During the Spring of 2009 and it’s Comparison With Drinking Water Outside the City Water DistrictEvaluation of THMs Concentration in Tehran’s Drinking Water During the Spring of 2009 and it’s Comparison With Drinking Water Outside the City Water District21483FAAlirezaPardakhtiAliTorabianJournal Article19700101This study intends to monitor and evaluate the THMs concentration in the 7 different water districts in the city of Tehran. THMs are the main disinfectant by products (DBP) of chlorination, which are suspected to be human carcinogens. Chlorination is used as the main disinfection process for the drinking water in Tehran, therefore; it is important to monitor and evaluate the THM’s concentration in Tehran’s drinking water. Samples were taken from twenty one locations across the city of Tehran in triplicates during the first week-end of April, May and June 2009 and analyzed for THMs using a Purge and Trap device coupled with a GC/MS instrument (EPA method 524.2). The data indicates that, the concentration of THMs are much higher in districts which are supplied mostly with surface water sources such as areas in the northern part of Tehran, compared to districts with well water as their main water source which are located mostly in the south and south west part of Tehran. The average concentration of chloroform, bromodichloromethane, dibromochloromethan and bromoform were 3.32 ppb, 2.82 ppb, 1.22 ppb and 0.16 ppb respectively. The observed THMs concentrations do not seem to cause a major adverse health effect on the population of Tehran, since the total THMs concentration is below the EPA’s recommended MCL value of 80 ppb.This study intends to monitor and evaluate the THMs concentration in the 7 different water districts in the city of Tehran. THMs are the main disinfectant by products (DBP) of chlorination, which are suspected to be human carcinogens. Chlorination is used as the main disinfection process for the drinking water in Tehran, therefore; it is important to monitor and evaluate the THM’s concentration in Tehran’s drinking water. Samples were taken from twenty one locations across the city of Tehran in triplicates during the first week-end of April, May and June 2009 and analyzed for THMs using a Purge and Trap device coupled with a GC/MS instrument (EPA method 524.2). The data indicates that, the concentration of THMs are much higher in districts which are supplied mostly with surface water sources such as areas in the northern part of Tehran, compared to districts with well water as their main water source which are located mostly in the south and south west part of Tehran. The average concentration of chloroform, bromodichloromethane, dibromochloromethan and bromoform were 3.32 ppb, 2.82 ppb, 1.22 ppb and 0.16 ppb respectively. The observed THMs concentrations do not seem to cause a major adverse health effect on the population of Tehran, since the total THMs concentration is below the EPA’s recommended MCL value of 80 ppb.دانشگاه تهرانJournal of Environmental Studies1025-8620365320100522Estimation of pollution brunt caused by environmental pollutants influential water Sabzevar CityEstimation of pollution brunt caused by environmental pollutants influential water Sabzevar City21484FAAli AkbarAnabestaniMohammadGhorbaniJournal Article19700101Nowadays, with population growth in urban areas, providing safe water and health is considered basic needs of human, alongside the various pollutants due to urban activities, agriculture and industrial areas on adjacent ranges into urban water resources around the environment is such that study necessary to prevent the pollution of water resources and identification of pollution sources shows. The purpose of this paper study identified water pollution sources in the confine of Sabzevar that are in the city water supply using data is available And methods for reducing pollution contamination of water sources must be examined. Results showed that nitrogen pollution load in the range studied in 2006, the 1725.9 tons. Therefore, agricultural pollutants due to the concentration of agricultural and garden lands in the surface of range studied and intensity of use of chemical fertilizers, pesticides and animal fertilizers, with 68.6 percent are the highest role and pollutants of urban and rural areas respectively, with 29.9 percent and industrial pollutants 1.5 percent have been. Regarding to, complete network Sabzevar collected sewage, Isolation industrial sewages from urban wastewater infiltration separately with the muster network set up and refinery sewage in the industrial units, implementation Sabzevar development plan of sewage refinery, Plan recognition and status of groundwater conditions confine plan to complete underground water resources database and the use of urban wastewater in filtering in agriculture sector for urban and rural areas has been proposed.Nowadays, with population growth in urban areas, providing safe water and health is considered basic needs of human, alongside the various pollutants due to urban activities, agriculture and industrial areas on adjacent ranges into urban water resources around the environment is such that study necessary to prevent the pollution of water resources and identification of pollution sources shows. The purpose of this paper study identified water pollution sources in the confine of Sabzevar that are in the city water supply using data is available And methods for reducing pollution contamination of water sources must be examined. Results showed that nitrogen pollution load in the range studied in 2006, the 1725.9 tons. Therefore, agricultural pollutants due to the concentration of agricultural and garden lands in the surface of range studied and intensity of use of chemical fertilizers, pesticides and animal fertilizers, with 68.6 percent are the highest role and pollutants of urban and rural areas respectively, with 29.9 percent and industrial pollutants 1.5 percent have been. Regarding to, complete network Sabzevar collected sewage, Isolation industrial sewages from urban wastewater infiltration separately with the muster network set up and refinery sewage in the industrial units, implementation Sabzevar development plan of sewage refinery, Plan recognition and status of groundwater conditions confine plan to complete underground water resources database and the use of urban wastewater in filtering in agriculture sector for urban and rural areas has been proposed.دانشگاه تهرانJournal of Environmental Studies1025-8620365320100522Groundwater quality analysis in Shahrekord aquiferGroundwater quality analysis in Shahrekord aquifer21485FARezaLalehzariSayed HasanTabatabaeiJournal Article19700101It is necessary to care the quantity and quality of the water resources especially in arid and semi-arid regions. Shahrekord plain where it has a 551 Km2 total area, groundwater is discharging almost 255 MCM annually and uses for drinking and agriculture. The main objective of this study was classification of groundwater quality and comparison with the drinking water standard limits in Shahrekord aquifer. Some of the chemical properties such as Cation, Anion, Electrical Conductivity (EC), Total Hardness (TH) and Total Dissolved Solids (TDS) were measured in four times (Spring and Autumn 2004 and 2005). The results show that the some of the chemical concentration in North-Western part (NWP) of the aquifer including Ca, Mg, SO4, HCO3, Cl and Na was lower than Southern part (SP). Bicarbonate in the Anions and Calcium in the Cations has the maximum values; however they are lower than the standard limits. Water type was assigned as Calcium Bicarbonate in terms of available ions combination in Shahrekord aquifer. The TH in the wells varies from 150 to 300 (mg/lit /CaCo3). The water quality is classified in hard water category base on TH. The result shows that there wasn’t considerable difference in TH and TDS values on spring and autumn seasons. The maximum nitrate concentration is about of 37 mg\lit in agricultural landuse of northern sites. Result shows that Total Hardness (TH) and Total Dissolved Solids (TDS) in southern parts and Nitrate concentration in northern parts have maximum values concentration. This subject shows that the source of these water quality parameters is difference together. Azotic fertilizer seepage of agricultural lands increase Nitrate contamination and urban wastewater had most effect to provide the chemical concentration and Total Dissolved Solids.It is necessary to care the quantity and quality of the water resources especially in arid and semi-arid regions. Shahrekord plain where it has a 551 Km2 total area, groundwater is discharging almost 255 MCM annually and uses for drinking and agriculture. The main objective of this study was classification of groundwater quality and comparison with the drinking water standard limits in Shahrekord aquifer. Some of the chemical properties such as Cation, Anion, Electrical Conductivity (EC), Total Hardness (TH) and Total Dissolved Solids (TDS) were measured in four times (Spring and Autumn 2004 and 2005). The results show that the some of the chemical concentration in North-Western part (NWP) of the aquifer including Ca, Mg, SO4, HCO3, Cl and Na was lower than Southern part (SP). Bicarbonate in the Anions and Calcium in the Cations has the maximum values; however they are lower than the standard limits. Water type was assigned as Calcium Bicarbonate in terms of available ions combination in Shahrekord aquifer. The TH in the wells varies from 150 to 300 (mg/lit /CaCo3). The water quality is classified in hard water category base on TH. The result shows that there wasn’t considerable difference in TH and TDS values on spring and autumn seasons. The maximum nitrate concentration is about of 37 mg\lit in agricultural landuse of northern sites. Result shows that Total Hardness (TH) and Total Dissolved Solids (TDS) in southern parts and Nitrate concentration in northern parts have maximum values concentration. This subject shows that the source of these water quality parameters is difference together. Azotic fertilizer seepage of agricultural lands increase Nitrate contamination and urban wastewater had most effect to provide the chemical concentration and Total Dissolved Solids.دانشگاه تهرانJournal of Environmental Studies1025-8620365320100522Comparison of Influence of Walnut Shell, Clay and Powdered Activated Carbon on Settleability of Activated SludgeComparison of Influence of Walnut Shell, Clay and Powdered Activated Carbon on Settleability of Activated Sludge21486FARouholahHosseinlouAmirTaebiJournal Article19700101The activated sludge process is the most used biological wastewater treatment method in the world. Sludge bulking is one of the most common problems relateing to activated sludge wastewater treatment, and this fact causes poor settling in secondary sedimentation tank. Sludge volume index(SVI) and the zone settling velocity(ZSV) are parameters to quantify the settleability of activated sludge . Assessment of influence of walnut shell as an agricultural waste, powdered activated carbon as a common adsorbent and clay as a mineral on the activated sludge settling properties was the principal aim of this research. Second phase of Shahinshahr Wastewater Treatment Plant was selected for wastewater sampling and conducting experiments of this research. SVI tests were done in a 1-Lit graduated cylinders and settling column used for determining of ZSV was with 200 cm height and 20 cm diameter. Average values of SVI for control sample was 823 mL/g, optimum dosages of walnut shell, clay and powdered activated carbon reduced SVI to 100 mL/g (88 percent decrease). Average values of ZSV for control sample was 1.222 m/h, different additives increased ZSV of control sample to 2-3 times. This increase in ZSV is important because hydraulic surface overflow rate(SOR) is also increased without loss of their efficiencies. Sludge return with these additives caused an improvement in sludge settleability. Jar tests revealed that these additives mainly act as ballasting agents rather than as flocculants and this mechanism is responsible for decreasing SVI. Walnut shell and clay, the same as activated carbon, improved the sludge settleability. Activated carbon is an expensive adsorbent and using this material is costly, while walnut shell and clay are cheep and natural. Therefore, walnut shell and clay can be used as alternatives of activated carbon.The activated sludge process is the most used biological wastewater treatment method in the world. Sludge bulking is one of the most common problems relateing to activated sludge wastewater treatment, and this fact causes poor settling in secondary sedimentation tank. Sludge volume index(SVI) and the zone settling velocity(ZSV) are parameters to quantify the settleability of activated sludge . Assessment of influence of walnut shell as an agricultural waste, powdered activated carbon as a common adsorbent and clay as a mineral on the activated sludge settling properties was the principal aim of this research. Second phase of Shahinshahr Wastewater Treatment Plant was selected for wastewater sampling and conducting experiments of this research. SVI tests were done in a 1-Lit graduated cylinders and settling column used for determining of ZSV was with 200 cm height and 20 cm diameter. Average values of SVI for control sample was 823 mL/g, optimum dosages of walnut shell, clay and powdered activated carbon reduced SVI to 100 mL/g (88 percent decrease). Average values of ZSV for control sample was 1.222 m/h, different additives increased ZSV of control sample to 2-3 times. This increase in ZSV is important because hydraulic surface overflow rate(SOR) is also increased without loss of their efficiencies. Sludge return with these additives caused an improvement in sludge settleability. Jar tests revealed that these additives mainly act as ballasting agents rather than as flocculants and this mechanism is responsible for decreasing SVI. Walnut shell and clay, the same as activated carbon, improved the sludge settleability. Activated carbon is an expensive adsorbent and using this material is costly, while walnut shell and clay are cheep and natural. Therefore, walnut shell and clay can be used as alternatives of activated carbon.دانشگاه تهرانJournal of Environmental Studies1025-8620365320100522Investigation of Using Fixed Activated Sludge System for Removing Heavy Metals (Cr, Ni and Pb) From Industrial WasteWaterInvestigation of Using Fixed Activated Sludge System for Removing Heavy Metals (Cr, Ni and Pb) From Industrial WasteWater21487FAAmir HesamHasaniImanHossenzadehBehzadTorabifarJournal Article19700101In this research the operation of fixed activated sludge system for treatment of wastewater containing heavy metal compounds, by use of FAS pilot ,a plaxy glass tank with three section; these section are downward-flow aerated reactor, upward-flow aerated reactor and gravity sediment unit, length and width and height of each part was respectively 15.7cm, 31.5cm , 51.5 cm and feeding with the synthetic wastewater containing proteins, lipids, carbohydrates and heavy metal compounds (chromium, lead and nickel) was studied. The aerated reactor is equipped with media made of PVC with surface area equal to 81.34 m2/m3. The obtained results show that COD removal percentage in the FAS has been about 96% and the acclimation time for microorganisms in this system is short.
At each stage increasing the concentration of heavy metals lead to a decrease both in COD and MLSS, and again the COD and MLSS increase, after the microorganisms acclimate with changes, but do not increase from the best previous stage condition of COD removal percentage, and the COD removal percentage has a downward movement. Heavy metals removal percentage in fixed activated sludge at the concentration of 1 mg/lit is 84%, 75% and 80%, respectively, and by increasing concentration of heavy metals at 5 mg/lit, the removal percentage is 90%, 84% and 87%, respectively. By increasing concentration of heavy metals at 10 mg/lit, the removal percentage is 85%, 95% and 92%, respectively, and by increasing concentration of heavy metals at 50 mg/lit; the removal percentage is 86%, 96% and 95.1%, respectively. By increasing concentration of heavy metals at 100 mg/lit, the removal percentage is 86%, 97.6% and 97%, respectively. Finally the microorganisms practically lose their efficiency to remove the heavy metals and COD at the concentration of 400 mg/lit of chromium, lead and nickel.In this research the operation of fixed activated sludge system for treatment of wastewater containing heavy metal compounds, by use of FAS pilot ,a plaxy glass tank with three section; these section are downward-flow aerated reactor, upward-flow aerated reactor and gravity sediment unit, length and width and height of each part was respectively 15.7cm, 31.5cm , 51.5 cm and feeding with the synthetic wastewater containing proteins, lipids, carbohydrates and heavy metal compounds (chromium, lead and nickel) was studied. The aerated reactor is equipped with media made of PVC with surface area equal to 81.34 m2/m3. The obtained results show that COD removal percentage in the FAS has been about 96% and the acclimation time for microorganisms in this system is short.
At each stage increasing the concentration of heavy metals lead to a decrease both in COD and MLSS, and again the COD and MLSS increase, after the microorganisms acclimate with changes, but do not increase from the best previous stage condition of COD removal percentage, and the COD removal percentage has a downward movement. Heavy metals removal percentage in fixed activated sludge at the concentration of 1 mg/lit is 84%, 75% and 80%, respectively, and by increasing concentration of heavy metals at 5 mg/lit, the removal percentage is 90%, 84% and 87%, respectively. By increasing concentration of heavy metals at 10 mg/lit, the removal percentage is 85%, 95% and 92%, respectively, and by increasing concentration of heavy metals at 50 mg/lit; the removal percentage is 86%, 96% and 95.1%, respectively. By increasing concentration of heavy metals at 100 mg/lit, the removal percentage is 86%, 97.6% and 97%, respectively. Finally the microorganisms practically lose their efficiency to remove the heavy metals and COD at the concentration of 400 mg/lit of chromium, lead and nickel.دانشگاه تهرانJournal of Environmental Studies1025-8620365320100522Phytoremediation of Phenanthrene from soil by SorghumPhytoremediation of Phenanthrene from soil by Sorghum21488FAEbrahimAlaieForouzanVakiliA.A.MehrdadSharifJournal Article19700101Investigations around some oil and gas refineries showed that Phenanthrene is the predominant form of PAHs in these areas. So, in this study, the role of Sorghum vulgare Pers. Sudanense (a warm season grass type) in removal of Phenanthrene from soils (Phytoremediation) in a 16 week period greenhouse study is investigated. The stress of Phenanthrene presence on plant's physiological activity, such as chlorophyll content and biomass was studied. To assess ecological risk of the method, pollutant accumulation in plant tissue was determined. All determinations were performed by HPLC and statistical analysis, T-Test and Tukey, was done by SPSS program. Results showed that in planted treatments there was a 20% increase in pollutant removal comparing with unplanted treatments. Furthermore, it was shown that the most of the Phenanthrene was degraded in the rhizosphere region and it didn't migrate toward upper parts of plant. Also, it was shown that Phenanthrene didn't affect plants physiological activities.All results was verified statistically in 95% significance level (P<0.05).Investigations around some oil and gas refineries showed that Phenanthrene is the predominant form of PAHs in these areas. So, in this study, the role of Sorghum vulgare Pers. Sudanense (a warm season grass type) in removal of Phenanthrene from soils (Phytoremediation) in a 16 week period greenhouse study is investigated. The stress of Phenanthrene presence on plant's physiological activity, such as chlorophyll content and biomass was studied. To assess ecological risk of the method, pollutant accumulation in plant tissue was determined. All determinations were performed by HPLC and statistical analysis, T-Test and Tukey, was done by SPSS program. Results showed that in planted treatments there was a 20% increase in pollutant removal comparing with unplanted treatments. Furthermore, it was shown that the most of the Phenanthrene was degraded in the rhizosphere region and it didn't migrate toward upper parts of plant. Also, it was shown that Phenanthrene didn't affect plants physiological activities.All results was verified statistically in 95% significance level (P<0.05).دانشگاه تهرانJournal of Environmental Studies1025-8620365320100522Estimation of the Preservation Value of Environmental Resources
(Case Study: Miankaleh International Wetland)Estimation of the Preservation Value of Environmental Resources
(Case Study: Miankaleh International Wetland)21489FAHamidAmirnejadHamedRafieeMiladAtghaeeJournal Article19700101According to importance of environmental resource in natural ecosystem preservation and human life, restriction of destruction is necessary. Miankaleh wetland in Mazandaran province is settlement of animal and herbaceous rare species and due to migration of birds therefore, this research will discuss determination of preservation value in Miankaleh international wetland and measure of individual’s willingness to pay (WTP) for Preservation benefits based on contingent valuation (CV) and questionnaire dichotomous choice. For measure of individual’s WTP was used Logit model and its estimation parameters are based on methods of maximum likelihood. Results show that 68.3% individuals have willing to pay for preservation value form the Miankaleh wetland. The mean of WTP for Preservation annual value of this wetland is RLs 6878.6 per household. The Preservation annual value was estimated 20.9 million RLs/ha for this wetland. Most important of effective variables are bid quantity, individual income, sex, education and jobs for preserve of this wetland. By using this results can be selected suitable price policy for preservation of Miankaleh.According to importance of environmental resource in natural ecosystem preservation and human life, restriction of destruction is necessary. Miankaleh wetland in Mazandaran province is settlement of animal and herbaceous rare species and due to migration of birds therefore, this research will discuss determination of preservation value in Miankaleh international wetland and measure of individual’s willingness to pay (WTP) for Preservation benefits based on contingent valuation (CV) and questionnaire dichotomous choice. For measure of individual’s WTP was used Logit model and its estimation parameters are based on methods of maximum likelihood. Results show that 68.3% individuals have willing to pay for preservation value form the Miankaleh wetland. The mean of WTP for Preservation annual value of this wetland is RLs 6878.6 per household. The Preservation annual value was estimated 20.9 million RLs/ha for this wetland. Most important of effective variables are bid quantity, individual income, sex, education and jobs for preserve of this wetland. By using this results can be selected suitable price policy for preservation of Miankaleh.دانشگاه تهرانJournal of Environmental Studies1025-8620365320100522Evaluation of Hospital Waste Management Process in Karaj's Hospitals.Evaluation of Hospital Waste Management Process in Karaj's Hospitals.21490FAAfsanehFaziliEsmaeilSalehi09123752788Mohammad AliAbdoliHamid RezaJafariMojhganShaikhpoorJournal Article19700101This study by the first, was carried out to evaluate and comparing Disposal waste management in Karaj's hospitals in 1387. Interview and observation methods were used to collect data and the study tool was a questionnaire. Data were analyzed by the SPSS, using chi-square and t-test. Regarding the condition of infectious waste generation, 64% of the hospitals had a good grade. Source separation of the waste were equipped in 100% of the units but did not completed and the domestic waste were mixed by the infectious waste at transportation time. But In general that function was in a good condition. the trashcans were in a good condition in 100% of these hospitals and in all of them infectious waste was kept in containers with special waste sacks and the collection of waste in 81/8% of the hospitals was done in special bins and 81/8% of temporary waste storage had enough place for the wastes. In all of hospitals waste wards equipped in three parts in day and thus the frequency of gathering waste was adequate. In all of these hospitals carrying and transportation of waste material equipped with trolleys, thus 100% of these were in a good condition. In 9.1% of these hospitals, infectious wastes was separated and disinfected by autoclaves and 9.1% of these hospitals had incineration facilities and therefore this function was in a poor condition. Unfortunately, the results have shown that the waste management in these hospitals was not on an appropriate level and in general, source separation, collection system from different wards, temporary storage and transportation in these hospitals were adequate, but the final disposal was very poor.This study by the first, was carried out to evaluate and comparing Disposal waste management in Karaj's hospitals in 1387. Interview and observation methods were used to collect data and the study tool was a questionnaire. Data were analyzed by the SPSS, using chi-square and t-test. Regarding the condition of infectious waste generation, 64% of the hospitals had a good grade. Source separation of the waste were equipped in 100% of the units but did not completed and the domestic waste were mixed by the infectious waste at transportation time. But In general that function was in a good condition. the trashcans were in a good condition in 100% of these hospitals and in all of them infectious waste was kept in containers with special waste sacks and the collection of waste in 81/8% of the hospitals was done in special bins and 81/8% of temporary waste storage had enough place for the wastes. In all of hospitals waste wards equipped in three parts in day and thus the frequency of gathering waste was adequate. In all of these hospitals carrying and transportation of waste material equipped with trolleys, thus 100% of these were in a good condition. In 9.1% of these hospitals, infectious wastes was separated and disinfected by autoclaves and 9.1% of these hospitals had incineration facilities and therefore this function was in a poor condition. Unfortunately, the results have shown that the waste management in these hospitals was not on an appropriate level and in general, source separation, collection system from different wards, temporary storage and transportation in these hospitals were adequate, but the final disposal was very poor.دانشگاه تهرانJournal of Environmental Studies1025-8620365320100522Environmental Risk Assessment of Gas pipelines by using of AHP Combined MethodEnvironmental Risk Assessment of Gas pipelines by using of AHP Combined Method21491FASayed AliJozi0000000244861297MehdiIrankhahiJournal Article19700101Nowadays environmental risk assessment is under consideration alike a useful tool in studies for environmental risk management of projects with high level of potential of destruction and hazards. Projects of Gas transportation pipelines, unlike technical and economical justification in the field of energy supplying for societies, by having danger on environment, need to the continuous studies of assessment and environmental risk management in manufacturing and benefiting stage. Applying risk assessment studies, are a step for identifying, classification and analyzing the risk generator agents and following, decrease of possibility for undesirable consequences and control the potential dangers of these type of plans are related to environment conservation. In this study, for purpose of environmental risk assessment for gas transportation pipelines, combined the indexing system method and Analytical Hierarchy Process. Indexing System is a compulsive and applicable method that was based at the basis of characterizing index effect and ranking. Final grade for environmental risk in this method produce via possibility of danger occurrence multiply with effect intensity. According to that efficiency scale for whole of criterias are not equal in the final level of risk, in this research, for the purpose of weighting the criteria’s, the Analytical Hierarchy Process was used and for the purpose of weighting the digital layers of information’s related to the criteria’s, Ordered Weight Analysis method was used. For the purpose of examinating results of this research, environmental risk assessment of gas transportation pipelines 24 inches for Tasuj-Salmas with approximate length about 42 kilometer as a case study was exerted.The most important identified risk generator agents of this project are related to the risks that came from third party damage potential and natural potentials (soil movement).Nowadays environmental risk assessment is under consideration alike a useful tool in studies for environmental risk management of projects with high level of potential of destruction and hazards. Projects of Gas transportation pipelines, unlike technical and economical justification in the field of energy supplying for societies, by having danger on environment, need to the continuous studies of assessment and environmental risk management in manufacturing and benefiting stage. Applying risk assessment studies, are a step for identifying, classification and analyzing the risk generator agents and following, decrease of possibility for undesirable consequences and control the potential dangers of these type of plans are related to environment conservation. In this study, for purpose of environmental risk assessment for gas transportation pipelines, combined the indexing system method and Analytical Hierarchy Process. Indexing System is a compulsive and applicable method that was based at the basis of characterizing index effect and ranking. Final grade for environmental risk in this method produce via possibility of danger occurrence multiply with effect intensity. According to that efficiency scale for whole of criterias are not equal in the final level of risk, in this research, for the purpose of weighting the criteria’s, the Analytical Hierarchy Process was used and for the purpose of weighting the digital layers of information’s related to the criteria’s, Ordered Weight Analysis method was used. For the purpose of examinating results of this research, environmental risk assessment of gas transportation pipelines 24 inches for Tasuj-Salmas with approximate length about 42 kilometer as a case study was exerted.The most important identified risk generator agents of this project are related to the risks that came from third party damage potential and natural potentials (soil movement).