JOURNAL OF ENVIRONMENTAL SCIENCE AND TECHNOLOGY
Year:2017 | Volume:19 | Issue:1 (72)|Papers Count:17

Background and Objective: Rainfall pattern is one of the most important and effective variable in flood simulation. Variation of rainfall intensity in each event is illustrated by rainfall pattern. Many random variable cause the stochastic property of rainfall pattern. According to the relation between rainfall pattern and flood, uncertainty of flood is related to the variability of rainfall pattern.Method: In this study, the RDP (Rainfall Data Processor), is used to quantify randomness characteristic of rainfall pattern in Symareh catchment.Findings: The obtain result shown, the Brust factor in rainfall events with long time duration and more depth is less than others. Also, more than 60 percent of observed events in Symareh catchment are belong to type 1 and 2 categories.Discussion and Conclusion the obtained result shown, the fraction of cumulative rainfall depth has not the same pattern. Also, the minimum uncertainty are related to the rainfall patterns that belong to the type 2 and has less depth and also more duration.

and pH in bulk precipitation samples collected in the Tehran city of I.R. of Iran were analyzed. In this article, Enrichment Factors, Correlation Analysis and Principal Component Analysis had been used in order to identify the sources of ions found in sampled rain waters.Findings: Results show that concentrations of the found substances were higher over the Mehrabad station. The mean concentration of ions indicated that, HCO3-, SO42- and NO3- were the main anions, while Ca2+, Na+, NH4+ and Mg2+ were the main cations. SO42- anion had important role in acidity of the rain water. The Bicarbonate anion had the highest concentration, among all other ions, over both stations and plays an important role in reduction of the acidity of the rain water. Study upon the potential sources of the ions over Tehran by means of Correlation Analysis, Enrichment Factor and Principle Component Analysis indicate that existence of Qom salt lake and desert in the south of the city were the main source of the Ca2+, Mg2+, K+ and Na+ There are anthropogenic sources for SO42-, NO3-, NO2-, F-, Br- ion’s. the other ions HCO3- and NH4+ were from anthropogenic and dust origin.Discussion and Conclusion: The pollutants in rainwater over Tehran were derived from long range and local (industry and traffic) sources.

Background and Objactive: Cadmium is one of the heavy metals resulting from wastewater of different industries, and it is also highly toxic to human and the environment. So, the cations of this metal must be removed or reduced down to effluent standards. The aim of the current study was to investigate the cadmium removal efficiency by modified wheat straw from aqueous solutions.Method: In this study, wheat straw as the adsorbent was prepared in a laboratory scale and pulverized by standard ASTM sieves (40-120 mesh sizes). Consequently, wheat straw was functionalized by using NaOH solution with concentration of 0.7 M. FTIR analysis was used to characterize the functional groups in the prepared adsorbent. Adsorption process was accomplished in a batch laboratory-scale with emphasis on the effect of various parameters such as mesh size, pH, contact time, initial concentration of Cd (II), adsorbent dosage and mixing rate on the adsorption efficiency.Findings: FTIR results showed that the modification of the wealth straw brought increase of stretch vibration band of hydroxyl and carboxyl groups. Optimized values for each factor to achieve the highest uptake were found to be as follows: the mesh size of 70, the contact time of 30 minutes, the initial concentration of 20 mg/L, the pH 7, the adsorbent dose of 1.5 g and the agitation speed of 240 rpm, at 25oC, respectively.Discussion and Counclusion: The maximum removal efficiency of cadmium was found to be %98.5, at the optimized experimental condition. In general, results showed that the modified wheat straw as an unusable and cheap sorbent could be consider for the removal of the cadmium ion with nearly complete removal efficiency, at the optimized condition.

Background and Objective: In recent decades, nanotechnology has affected different aspects of human being life. This technology has various impacts on economics, production and subsequently environment of each country. Nanotechnology could have both positive and negative impacts on environment. The use of this technology reduces the energy consumption, production of by products and greenhouse gas emission. However, nanoparticles might increase the growth of bacteria which is a threat for both environment and public health.Methods: In the current study using panel data method, the impact of nanotechnology on environment in both developed and developing countries (such as Iran) for a period of 13 years (1997 to 2010) is investigated.Findings: The results indicated that using nanotechnology in developed countries mitigated the impacts of increased pollution, as a result of economic growth, industrial and population growth on environment; however, in developing countries using this technology did not have significant impacts on environment Discussion and Counclusion: Due to the significant positive impact and nanotechnology in reducing the pollutants in developed countries can be concluded so what developing countries will also be given to the importance of nanotechnology can be effective in reducing air pollution.

Background and Objective: The hydrograph and maps of groundwater level variations in Kashan aquifer demonstrate that during 2002-2011 the level of groundwater with depth moderate of 72.06 meter has decreased about 5.5 meter. When dealing with the quality of water resources for defferent uses, collecting samples from all parts of a study area is not economically possible, In this regard zoning methods are powerful tools in the providing the data based on spatial-temporal variations. This research aimed, modeling of level, depth and spatial-temporal variations Kashan aquifer groundwater table based on Cross validation technique of different methods of deterministic and geostatistic interpolation in GIS environment.Method: water level data of 67 observational wells in the region have been surveyed and compared to mapping of Kashan groundwater level during 2002-2011. Cross validation techniques have been employed and some criteria such as mean biased error (MBE), mean absolute error (MAE), root mean square error (RMSE) and R2 have been used to assess the performance of different methods and choosing the best one.Findings: The results indicated that the local polynomials method with MBE=0.444, MAE=13.19, RMSE=20.29 and R2=0.999 possessed the highest accuracy.Discussion and Counclusion: As well as the results of this study showed that residential areas with high population due to the high aggravation of net recharge and forest areas increased groundwater level and activities in the industrial, agricultural and water extraction have caused a drastic reduction in groundwater level.

Background and Objective: Nowadays, landscape would be regarded as one of the main elements of identity, existence, stability of the environment and a connector between the environment and its users. In this regard, landscape and its relationship with people perception are very momentous.Analysis of the relationships between visual quality and structural characteristics of landscape is an effective method in cognitive researches. In general, studies which are performed based on the aesthetic criteria of landscape not only are searching about the beauty or excellence of landscapes but also are looking for the users' aesthetic preferences. In this study the goal is to prioritize walking tracks of Ziarat basin from the point of cognitive and aesthetic value by using conceptual approach.Method: For this purpose, field survey of walking tracks was conducted to take photographs and mark the viewpoints. Finally a questionnaire survey was developed to investigate the landscape preference which ordinal classification was used in it. Questionnaires were distributed between 217 of visitors.Data which obtained from questionnaires were analyzed by using SPSS software.Findings: The results showed that the walking tracks of the study area are totally different from the point of visual quality and due to visitor preference, Talambar walking tracks has attached the first priority and Sefid cheshmeh has attached the last priority.Discussion and Counclusion: The results of this paper would lead to introduce preferable walking tracks and special view points and landscape of each walking tracks. The results could also help the managers to develop more beautiful trails, and to design and construct sightseeing places along the trails for visitors.

Background and Objective: Nowadays due to the diffusion of various types of contamination, particularly heavy metals, into soil, the subject of soil pollution has gotten special significance. Indeed, lead is a heavy metal that enters soil from various sources, specifically through burning gasoline. The aim of this study was to evaluate the phytoremediation potential of marshmallow plant (Althea officinalis (for the absorption of lead.Method: In this study, the uptake of lead by marshmallow plant was examined in the city of Ahvaz during 1392. The investigation was carried out through the use of lead nitrate while watering plants, and was followed by sampling and extraction of the roots and shoots. Digestion of the samples and measurements were analyzed by atomic absorption. Consequently, the results were considered in great detail using Spss software.Findings: The results indicated the maximum absorption with attracting 50.96 micrograms per kilogram in the blossom after the treatment of 25 ppm. Treated with 50 ppm maximum absorption occurred at the root with 63.24 micrograms per kilogram, and in the treatment of 100 ppm maximum absorption was observed in the blossom with the 43.50 mg kg. Overall, following the treatment of 50 ppm, the root contributed for the maximum absorption with 63.24 mg kg, and the leaf had the minimum absorption with 26.35 mg kg.Conclusion and Discussion: Results obtained from this study illustrated that marshmallow is a potential extracting plant. It is recommended this plant be examined for the absorption of other heavy metals.

Background and Objective: The presence of the high concentrations of selenite in the industrial wastewater that and subsequently entering water supply and the food chain are being health concerns.Thus, microbial bio-remediation has been considered as a safety tool for removing selenite. The aim of the current study was to evaluate the capability of selenite removal using Selenite-resistant Lactobacilli isolated from local cheeses made in the rural areas of Kurdistan.Method: 25 local sample were collected from pristine areas kordestan province Enrichment was performed in the MRS media containing selenite (SeO3-2). Selenite tolerance pattern among bacterial isolates was performed by using the agar dilution test and broth dilution method.The selenite content in the reaction medium was measured by a colorimetric assay. The One-factor-ata- time method (OFAT) was used for the process optimization. Molecular characterization was performed by amplification of 16S rDNA gene and sequencing.Findings: A total of 30 selenite-resistant bacteria were isolated and one of the strain, named Lactobacillus sp. Tra cheese 6, show the highest resistance to selenite (125 mM) along with bioreduction efficiency. The maximum selenite removal was observed at the following conditions: initial biomass concentration 50 g/l, NaCl 4% (w/v), Temperature 37 C, pH 7.2 and agitation 100 rpm in the presence selenite with initial concentration of 45 mM. Under the optimal conditions, the concentration of SeO3-2 ion in the reaction supernatant decreased by 96% (from 45 to 1.8 mM) after 60 hours of incubation.Discussion and Conclusion: Regarding the results obtained in the current investigation, isolation and determined of Lactobacilli as safety and economic catalysts and to develop suitable alternative methods for the removal of heavy metal oxyanions from water and wastewater are suggested.

Background and Objective: The extent of spread and source degradation would be determined using prediction of land use/ land cover changes. In this way these changes would be guided in the right directions. The aim of this study is modeling the process of land use / land cover changes of Hamedan province using Landsat TM satellite image of 1989 and IRS LISS III image of 2008.Method: After running the necessary corrections, land use/ land cover maps of the study area in the past two years were obtained using supervised classification with maximum likelihood algorithm.Then probability matrix of land use transition (to each other) were calculated using Markov chain with respect to land use/ land cover map. In the next step, Cellular Automata method was used to geo specified these changes.Findings: Finally land use/ land cover map of Hamedan province for 19 years later (2024) was obtained and the area of each land use/ land cover was calculated.Discussion and Counclusion: The results of this research shows that natural land use/ land covers will be decreased and transmited to human land uses in future. These changes are conceivable due to population growth and increasing human needs to exploit the nature; but this process should be considered to exploit the natural resources in a sustainable manner to avoid severe consequences in future.

Background and Objective: Selecting a suitable interpolation method is a main factor of surface analysis and it is a difficult task in geostatistical analysis since different methods of interpolation can result in different surfaces and ultimately different results. Hence, the aim of this study is to evaluate the performance of different interpolation methods in determining the spatial concentration of Cd, Zn and Cu in the Surface soil of Aran-O-Bidgol City.Method: A total of 135 surface soil (0-20 cm) samples were collected in the study area and the soil heavy metals concentrations were determined. The spatial distribution of heavy metals concentration in Surface Soil of Aran-O-Bidgol was evaluated using different interpolation methods including ordinary Kriging, CoKriging, Inverse Distance Weighting, Local Polynomials and Radial Basis Function. Cross validation and MSE, MBE, RMSE, NSE, PBIAS were applied to estimate their accuracy.Findings: According to the results Ordinary Kriging (spherical model) had the best efficiency for estimating Cd and Cu concentrations and Ordinary Kriging (exponential model) had the best efficiency for estimating distribution pattern of Zn concentration in the soil of this region. The weight parameter has a significant influence on the accuracy of interpolation. The higher the order of local polynomial, the larger the accuracy of cross validation, whereas, the greater the weighting power of IDW for Cd and Zn, the greater error and larger accuracy of the interpolation will be for Cu.Discussion and Conclusion: Although all of the considered interpolation methods had a high prediction accuracy of the mean content for soil heavy metals, but taking all cross validation indicators into consideration, Ordinary Kriging (OK) method shows a generally better performance than other methods.

Background and Objective: Population growth, industrial development and increase in quality and quantity of consumer products has led to the increase of waste generated. According to Department of Municipal Utilities of Bukan an average of 189 tons of waste is generated daily, that means per capita waste generation is about 640 to 820 grams per day, which is slightly higher than the country average (the equivalent of 600 to 800 grams per day).Therefore the selection of a municipal waste landfill is one of the most important steps and goals in management of municipal solid waste of Bukan.Method: This study is analytical-descriptive, therefore by full recognition of locating criteria such as communicational lines, distance between rural and urban areas, surface waters privacy, distance from fault, land usage, slope and the direction of slope which play critical rule in selecting the waste landfill site and utilizing Boolean Logic and weighting of layers using AHP model in GIS software, the best location for landfill waste is selected based on mentioned criteria.Findings: Results obtained from the poll of experts in the AHP model has showed that Hydrology criterion with a weight of 0.235 as the most important and land use with a weigh of 0.023 as the least important one have been known. Also after extracting the information layers of criteria from the maps and prioritizing locating ranges in 5 classes, it has been found that there are notable zones to landfill waste in the city of Bokan which ultimately a zone with the area of 138 Hectares is chosen. The selected are is located between Bokan and Simineh and to the south of Kani Shaqaq village.Discussion and Conclusion: Generally, considering the results of the presented research, it can be said that prioritised ranges for positioning can be determined by combining the Boolean logic method and AHP model, acceptably.

Background and Objective: With population growth and industrialization, our environment has been exposed to serious threats in recent decades. One of the most important threats is the human performance that has incurred so many serious damages to the environment, because of the lack of sufficient knowledge. By increasing the knowledgs and understanding of people, we can take a great steps to have a better protection of environment. The purpose of this research is to study the role of education on air pollution (growth of CO2 emission) in selected MENA countries.Method: For hypotheses testing, the dynamic panel data (DPD) and the Generalized Method of Moments (GMM) has been applied for 12 selected MENA countries including Iran during the years between 1992 to 2012.Findings: The findings of this study show the meaningful and positive impact of the education variable (at different educational levels) on the improvement of environmental quality and the decrease of air pollution.Discussion and Counclusion: At the MENA selected countries, the higher the educational level, the less the air pollution decreases. In other words, the effect of education is stronger at the elementary education level. Therefore, the expansion of public education levels with emphasize on elementary schools, about environmental protection in Iran and other MENA countries is suggested for the improvement of environment quality.

Context and Purpose: The aim of this research was to investigate agricultural students' awareness, attitude and behavior toward sustainable development at Arak University.Methodology: Survey method was applied in this research. The statistical population of this study was agricultural students at Arak University from which 101 students were selected using simple randomized sampling. A questionnaire was developed to gather data. Validity and reliability of the research instrument were confirmed based on the evaluation of experts and Cronbach’s Alpha coefficient (environmental behavior=0.78, environmental awareness=0.71 and attitude toward environment=0.79) respectively.Findings: The findings indicated that 77.2% of the students had a high level, 20.8% had a medium level and 2% had a low level of awareness toward sustainable development. Furthermore, 33.7% of the students had a strong, 36.6% had a moderate, and 29.7% had a weak attitude toward sustainable development. The results of correlation analysis revealed that there was a significantly positive relationship between these sets: awareness and attitude, awareness and behavior, and attitude and behavior toward sustainable development. The relationship between students' attitudes and behavior toward sustainable development with G.P.A. were also significant. Stepwise regression analysis indicated that attitude and gender predict 57% of variation in the agricultural students' behavior toward sustainable development.Conclusion: environmental education and changing students' attitude toward environment are prerequisites for achieving sustainable development.

Background and: Linden is one of threatened species in north of Iran that form very small percentage of the northern forests. Since the linden seeds are facing with germination problems such as with dual physiological (the embryo) and mechanical (hard cover pericarp) dormancy that application such as tissue culture can be effective in planting, restoration and conservation of genetic resources.Method: This study was carried out in order to determine the most suitable explants and the best hormone combination to optimize micropropagation of linden in vitro. Explants were collected and cultured randomly from the best individual of linden from Gorgan Touskaestan forest.Findings: In light of results, from the eleven tested explants, stem containing terminal buds with scale were selected as the most suitable explants and IBA 0.1 mg/l was selected as the most appropriate medium hormonal combination in shoot regeneration.Discussion and Conclusion: Obtained data were analyzed with a completely randomized design by MSTATC software. It is hoped that the achieved results can be reproduced and be helpful in tissue culture research and also the molecular basis studies.

Background and Objective: Extensive development of nanotechnology and applications of nanoparticles in different industries has caused devastating effects of nano-materials on organisms. This study aimed to evaluate the effects of nano zinc oxide on hematological factors of goldfish.Methods: In this paper we determine the range of concentrations of zinc oxide nano-particles to determine LC50 of gold fish at 24, 48, 72 and 96 hours respectively. Then, according to the LC50, separate experiments were designed to induce sub-lethal concentration of this substance on Hematological parameters were studied. Blood samples of goldfish fry were taken in the 7 days following exposure to lethal concentrations (50% concentration) of nano-ZnO nano-materials with fish that were not exposed.Findings: The results showed that the nano-particles could changes in blood parameters of gold fish by increasing red blood cell (RBC), hemoglobin, hematocrit, MCV in treatment was influenced by the nano-particles, was (P>0.05) and reduced white blood cell (WBC) in the treatment of fish exposed to lethal concentrations of nano-particles compared to the control group (P>0.05) but did not show significant change in MCH, MCHC indices.Discussion and Conclusions: In conclusion sub-lethal concentration of nano zinc oxide could affect hematological parameters of goldfish and this fish have more resistance to this kind of pollutant.