عبدالرضا کرباسی

One of the problems of management programs to control and reduce air pollution in Iran, especially in Tehran, is the lack of prioritization and the level of effectiveness of executive steps in order to focus human and financial resources. Therefore, step-by-step performance considering executive priority is a suitable solution to achieve this goal. Using the DPSIR framework in the SOE study of Tehran air pollution provides a systematic and comprehensive method to understand and address this critical issue. It not only helps in diagnosing the problem, but also in formulating and evaluating effective solutions, thereby contributing to the sustainable development of the city. The AHP-DPSIR hybrid model is a suitable model for finding the prioritization of environmental programs with a comprehensive and managerial approach, considering uncertainty with a hierarchical structure. In this study, responses to the improvement of pressure factors, stimulus, current situation and effects were investigated and compared in a hierarchical format, and at the end, their preference level was obtained. Development and improvement of public transportation, improvement of fuel quality, improvement of vehicle emission standard, technical examination of vehicle and finally urban traffic management were recognized as the implementation steps of Tehran's air pollution control and reduction program. The model developed in this study is suggested for use in similar cases, especially in developing countries that face the same management problem as Iran. This model has high flexibility and accuracy in prioritization with a comprehensive approach.

Monitoring the concentration of heavy metals in marine sediments is very important for identifying existing and potential risks and developing prevention programs. In the present study, considering the various unloading, loading and shipping activities in Shahid Bahonar Port, the concentration of heavy metals including chromium(Cr), zinc(Zn), copper(Cu), nickel(Ni), mercury(Hg), arsenic(As), manganese(Mn), cobalt(Co), iron(Fe) and cadmium(Cd) in the eleven stations of marine area of the port was measured by atomic absorption method. The Muller's indices (Igeo), contamination factor (CF), contamination degree index (Cd), modified contamination degree index (mCd) and RI ecological risk assessment index was calculated. The average value of metal concentration was compared with NOAA and ISQGs international sediment quality standards as well.The findings showed that the highest concentration of heavy metals was related to iron > manganese > zinc > chromium > nickel > copper > cobalt > arsenic > cadmium > mercury respectively. The average value of heavy metals concentration measured in the sediments in terms of milligrams per kilogram was calculated as arsenic (3.4), cadmium (1.2), iron (22261.4), copper (61.64), zinc (116.3), manganese (333.79), mercury (0.23), cobalt (26.29), chromium (177.92) and nickel (90.96) ) respectively. The results of ecological risk indices show that heavy metals contamination is moderate or considerable in most of the studied stations and the stations inside the port basin have a higher cumulative risk than those outside the port.According to the obtained results, it can be said that the port activities, the discharge of the balance water of the ships, as well as the closure of the port basin and the low ratio of water exchange to the outside of the basin are factors that cause settlement and accumulation of heavy metals in the sediments

The use of ozone in water and waste water treatment and health and food industries has found an exponential trend due to its compatibility with the environment. Ozone, which is a triatomic molecule of oxygen, is a strong oxidant and unstable free radical that quickly combines with other substances or turns into oxygen after decay. The production of ozone with electricity is simple, but the main challenge is the high cost of electricity consumed by ozone generators. The purpose of this research was to design and build ozone generating devices with less electricity consumption.

In this research, after computer simulation, various types of ozone generators and plasma generators were made with the approach of reducing energy consumption. Since all these equipments are composed of three components, frequency increasing circuits and voltage increasing transformers and reactor based on electric discharge in gas, after designing and simulating all three parts separately, we proceeded to build a complete pilot device for color removal. And the water was disinfected.

by making an ozone device that consumes as much as a 30-watt low-power light bulb and by injecting this device's ozone for 5 minutes into water with methylene blue color pollution as an indicator of color pollution and Escherichia coli as an indicator of microbial pollution , while decolorizing, 99% microbicide was achieved in water.

In order to produce ozone from cold plasma, integrated construction and simultaneous optimization of the circuit, transformer and reactor have been done. According to the high frequency inverter designed in this research, the ozone production reactor works at a lower temperature.

Industrial plating wastewater contains various types of detrimental heavy metals in high concentrations. One of this toxic metal is Nickel that its discharge into the surface waters and soil is considered as an environmental problem. Hence removing of this metal from wastewaters is crucial and vital for protecting the environment and human health. Applying of nanotechnology in elimination of environmental contaminants is one of the methods which attracted a great deal of attention in recent years. In present research, nanographite was utilized as efficient adsorbent in order to remove Ni ions.

In order to investigate the adsorption process, nanographite with a purity of 99.9% and a specific surface area of ​​18-24 m2/g and a plate morphology was prepared from Pishgaman Iranian Nanomaterials Company and used as an adsorbent. Also, the wastewater used in the experiments was prepared from one of the plating workshops in Tehran, which contained 765 mg/L of nickel and a pH of about 1. The parameters of pH, time and amount of adsorbent were evaluated. In each experiment, one of the parameters was considered variable and the other two parameters were considered constant. The amount of nickel was determined before and after each test.

In this study, the parameters including pH, adsorption time and adsorbent dosage were investigated as effective factors on Ni adsorption process. In order to analyze the adsorption mechanism, the obtained results were examined by the Langmuir and Fruendlich isotherm models. In addition, pseudo-first-order and pseudo-second-order models were studied to investigate adsorption kinetics. According to the results, the Ni uptake by nanographite was enhanced significantly with increasing of the pH value from 5 to 7. Thus the pH of 7 was determined as optimum pH for Ni removal. Investigations also showed that increasing the time up to the first 80 minutes had a relatively good effect on nickel adsorption by the nanoparticle, and after that the adsorption almost reached equilibrium. Finally, it was observed that in a constant time, increasing the amount of adsorbent led to an increase in adsorption, and to achieve the maximum adsorption of nickel, the amount of 2g was chosen for the adsorbent. Based on the obtained results, 97.52% primary nickel was adsorbed by nanographite. Results also revealed that the data were best fitted to the Fruendlich models. After determining the amount of nickel adsorption at different times, the resulting data were analyzed by the kinetic model.Kinetic studies also indicated that the adsorption data were described well by pseudo-second-order model.

Examining the results showed that pH plays an important role in the adsorption process and the adsorption rate increases with increasing time until the equilibrium time is reached. One of the effective factors is the amount of adsorbent, which has a direct effect on adsorption. Following the Freundlich isotherm in this research indicates that the adsorption sites in the adsorbent have different energies. Also, the pseudo-second-order model in adsorption kinetics refers to the process of chemical adsorption in addition to physical adsorption.

Background and Theoretical Foundations: 

The environmental issues resulting from the commercial activities of the ports and their support in backshore are often reflected in the coastal-marine environment area. because any type of pollution with a known or unknown origin can eventually affect the marine environment as well.

In this study, considering the importance of Shahid Bahonar port and a extensive of loading, discharging and shipping activities of this port, Sampling of sediments was done in 11 stations in the basin and sea area of ​​this port in 1400 and 1401 and the concentration of heavy metals and aromatic petroleum hydrocarbon  was measured. .

Average concentration of heavy metals in sediments for arsenic (3.40), cadmium (1.20), chromium (177.29), iron (22261.40), copper (61.64), zinc (116.35), manganese (333/79), mercury (0.23), cobalt (26.29) and nickel (90.96) mg/kg were measured.  Also, about petroleum hydrocarbons, the results showed that among the 16 aromatic compounds studied, the highest concentration of Fluoranthene with 507.6 ng/g was measured at station 2 and the lowest concentration of Naphthalene was measured with 1.4 ng/g. According to the ecological risk assessment, the highest level of pollution is in the stations in the basin of the port and oil jetty with a medium degree of pollution, and the stations inside basin have a higher cumulative risk than outside the port.

 According to the obtained results, it can be said that port activities, marine repair activities of neighboring industries, the closure of the port basin and the low ratio of water exchange in the basin are factors that cause the accumulation of heavy metals and petroleum hydrocarbons in the sediments.

An accurate estimation of air quality and meteorological conditions is required to make the sound air pollution management decisions. Thus, the data analysis from monitoring stations is unavoidable in air pollution research.  The present study uses the statistical tests to survey the homogeneity of meteorological factors and air quality station data in Mahshahr.

At first, a decade's worth of meteorological station data and the data from air quality stations in Mahshahr were collected over 2016-2019. The minimum and maximum values, standard deviation, variance, skewness, and kurtosis of parameters were then calculated, and heterogeneities and improbable fluctuations in the data were examined.

The results indicated that an average of 12% of data from the meteorological station in the special region were invalid, and that the data from this station had a non-normal distribution. Moreover, 98% of meteorological data collected at Mahshahr airport were valid which had a normal distribution. Statistical analysis of pollutant concentration data from air quality stations revealed that among 21 pollutants monitored across four air quality stations in the study region, only PM2.5 in Mahshahr station, NO2 in the mobile station, and CO, O3 in the special region fix station yielded normal distributed data.

Consequently, when compared to other regional stations, the data from special zone's fixed air quality station, and Mahshahr meteorological station were the most reliable, with an average invalid data percentage of 16.4 and 0.48, respectively. Finally, it is recommended that the data should be adjusted to a more normal distribution over the desired period before using the data from other stations.

The present research has been performed to investigate the opportunities and challenges facing the Iran’s renewable energies development to reduce climate change and improve health and represent managerial solutions in power generation sector by SWOT-AHP analysis models.

Using literature reviews and survey, the SWOT was applied to identify internal factors includeding strengths (S), and weaknesses (W), and external factors includeding opportunities (O), and threats (T). The strategies were drived to develop renewable energy in Iran. The proposal strategies were ranked by using the SWOT matrix and analytic hierarchy process (AHP) model.

According to the SWOT matrix calculations, total scores of internal and external factors were found as  4.1 and 4.4 of 5, respectively, which show high potentials of internal factors and opportunities. The most importannt factor of strengths (S) was found to be the great potentials of solar energy sources in Iran. The main priority of opportunities (O) is supportive laws to encourage the private sector. The most important weakness (W) was lack of comprehensive knowledge of managers and politicians about the benefits of renewable energy. The main threats (T) were low tendency of private invests, unpredictable inflation in Iran, and low prices for fossil fuels.

The results of this research represent in four categories of SO, ST, WT, WO strategies. The important SO strategy is increasing guaranteed electricity purchase tariffs (GEPTs), and creating the renewable energy market. The most important strategies of ST were establishment of the renewable energy fund and assessment of exporting electricity by the private sector. The most dominant strategy of WT was modifying guaranteed electricity purchase contracts. The strategies of WO were found to be as following; convincing government agencies to provide the necessary infrastructure and support for knowledge-based companies.

 In designing ecological industrial parks, an attempt is to maximize the self-purification of the system by defined mechanisms in order to reduce the pollution produced by industries first and then, to reuse the by-products of industrial processes. Due to the high vulnerability of the coastal sector, species diversity and rapid sequence in the region, the use of environmental methods in the environment of shahid salimi powerplant (Neka) is inevitable. The purpose of this study is to calculate and model the distribution of SO2, NOx pollutants to be displayed seasonally and annually using ADMS software in the form of GIS layers and to achieve the design criteria of an eco- industrial park in the study area, the mass flow of SO2 and NOx is calculated in gr/sec and also the flue smoke of the powerplant fuel consumption is analyzed in cold and hot seasons of the year separately. The results showed that in Neka power plant, the average concentration of NOx gas per unit of steam is 304 μg/m3 and in combined cycle unit is 77.75 μg/m3 and also the average concentration of SO2 per unit of steam is 267.25 μg/m3 during the year which does not meet any of WHO and European clean air standards.

In recent years, due to limited water resources and the extraordinary increase in nitrates in the environment, efforts to remove and control in order to benefit from the natural adsorbents have been made. Although according to the negatively charged surface of bentonite particles, absorbent needs improvement.

In the current study, the adsorption of nitrate columns by the modified calcium montmorillonite adsorbent was investigated. Furthermore, In order to change the surface load and increase the adsorption efficiency, three-step acid leaching, oxidation layering, and loading of the cationic surfactant hexadecyltrimethylammonium bromide on the adsorbent were performed. Molecular interaction and crystallography of pure montmorillonite and synthetic nano-adsorbent (ACZ) were characterized by Fourier transform infrared spectroscopy and X-ray analysis. Moreover, the morphology of ACZ nano adsorbents was evaluated using Transmission electron microscopy and scanning electron microscopy.

Nanoparticle compaction and less access to pores and cavities in the fixed bed column reduced the adsorbent capacity inside the column compared to the discontinuous system.The results showed that an increase in inlet concentration from 80 to 150 mg/L increased the adsorption capacity from 67.39 to 88.25 mg/g. Reducing the inlet flow rate increased the penetration time, interaction, and greater access to the binding sites for nitrate ions and finally improved the column performance and increased the inlet flow rate reduced the adsorption capacity and breakthrough time. Therefore, the adsorption of nitrate ions by the stage of internal mass transfer is controlled and depends on the duration of interaction and the possibility of penetration into the active sites. With increasing the bed height from 4.2 to 9 cm, there was a significant increase in adsorption capacity from 60.608 to 77.167 mg/g. The effect of detergents and recovery showed an absorption column; After 3 leaching steps, acid leaching played an important role in increasing column recovery. Experimental data with correlation coefficients of R2>0.95 corresponded to Thomas and Yoon-Nelson kinetic models.In this study, the ACZ nano adsorbent column for rapid removal of nitrate ions from aqueous solutions was introduced and for use in reusable systems was proposed.

Ordinary Kriging (OK) has been widely used for prediction and spatial distribution study of surface water quality parameters. This method uses a constant mean to capture the trend in the model. In this method, the prediction can be poor if there are strong trends. To overcome this problem, an alternative model called Blind Kriging (BK) was developed. The mean function in BK is polynomial and the unknown mean function parameters are obtained using the Bayesian variable selection technique which requires a lot of calculations. To solve these problems, in the present study, OK was modified based on BK. In the modified method, the polynomial mean function parameters were determined using linear Regression instead of Bayesian inference method. Then, the performance of OK and modified Kriging in the estimation of trophic indices and water quality parameters in Anzali Wetland was evaluated using different statistical criteria (the coefficient of determination, the root mean square error and the mean absolute error). For this purpose, the concentrations of 14 parameters in six sampling points of Anzali Wetland water were analyzed during 2018. Subsequently, the modified and Ordinary Kriging were applied to water parameters and trophic indices. The results showed that the modified Kriging had the best results. In addition, the improvement of the modified Kriging compared to OK is achieved up to 88%. The results of the present study can be useful in the planning of the future monitoring program in Anzali Wetland.

The study of the response and adaptation of the trees' leaves exposed to air pollutants is a good indicator of plant yield in contaminated environments. In this study, the effect of metal contaminants on changing the morphological traits of platanus orientalis leaves in Chitgar and Azadi Square in Tehran was investigated.

Two areas were selected for sampling. Area one was a low-traffic environment (from the interior space of Chitgar Park) and a high-traffic environment (Azadi Square). In each area, five healthy and disease-free tree base of plantain type (Platanus orientalis) were randomly selected at the shortest distance from the street. Completely healthy leaves were collected from the outermost part of each tree canopy from the street side in the first half of September. The leaves were collected at 10 to 11 am. To ensure that the stomata were open. The leaves were put in wrapped nylons in an ice tank with minimal hand contact and transported to the laboratory in the shortest time. Morphological traits of plantain leaves and stomata were measured. Metal concentration was also measured.

Pb, Hg, Fe, Cu, Cr, Co, Cd, and Ni were more polluted than other metals and their toxicity in Azadi was more than Chitgar. The results of the study indicated that in the presence of heavy metal contaminants in the environment, the leaf length, width, area, fresh and dry weight, and the relative water content decreased while the dent per area unit, vein distribution per blade area, and special area of the leaf increased. As Cu increases, the leaf area decreases and the symptoms of Cholosis appear. The accumulation of cadmium, lead and nickel will reduce the size of Mesophile tissue and epidermal cells. Dry and fresh weight of platanus orientalis leaves in Azadi reduced in comparison to Chitgar. The decrease of dry weight is a complication of cadmium toxicity. Stomatal length, width, and size decreased while stomatal density increased. Stomatal strength, stomatal density, and stomatal size increased in upper leaf area.

By decreasing the contact surface with the pollutant and changing the stomatal size and density, platanus orientalis adjusts gas exchanges with the environment. The occurrence of these morphological adaptations increases the stability of platanus orientalis to the air pollutants stress.

The HVO production unit is one of the refineries' pollutant units, which often has a CO, THC, NOx, SOx and CO emissions higher than the standard limits. By investigating the operational parameters and determining their effect on pollutants, the viscosity of the feed was determined as one of the important parameters and evaluation measure. The emitted amount of CO pollutant was measured in several feeds with different viscosity characteristics, by decreasing the pollutants temperature, changing combustion chamber temperature(energy consumption)and adjusting other process and production conditions in two product categories: HHVO, LHVO. The amount of CO pollutant emission from LHVO production process is far less than the HHVO production and this amount is reduced by increasing the viscosity of the feed and reducing the outlet pollutant temperature of the reactor. For example the amount of CO emission in same operational condition is 1280 mg/nm3 for LHVO process but for HHVO process is 1740 mg/nm3 and the amount of this pollutant is 1619 mg/nm3 for HHVO process in normal emission process but decrees of pollutants temperature has resulted in decrease of emission to 690 mg/nm3. Finally, the results was analyzed and reported in accordance with the specified parameters.

In recent years, urbanization has been one of the most significant processes of change in society, which is usually accompanied by the destruction of agricultural and natural lands. In their decision-making processes to protect the urban environment, managers need to properly consider the extent and direction of urban growth. The purpose of this study is to predict changes in urban land use in the city of Tabriz, using the SLEUTH urban growth model. The output of the model predicts the growth rate and direction of the city by 2050. The five coefficients obtained for the study area show that according to the historical scenario, the birth rate and the diffusion coefficient are dominant. The high rate of fertility in this area indicates that the probability of converting each urban cell to a city center diffusion cell is high, and as a result, the growth rate of the new diffusion center in the covered area is also high. The high emission coefficient indicates the high probability of new urban spots resulting from spontaneous growth and their transformation into new centers of urban growth. The results of validation using Kappa coefficient show that the modeling has an accuracy of 97.72%. The obtained results can be used to predict the change of urban land use. The obtained results are the outcome of instrumental rationality, and therefore their application requires a critical approach to them.

Monitoring the magnetic properties of suspended particles in the air deposited on the leaves of trees provides useful information on the spatial distribution of the suspended particles in urban and industrial areas. This study was carried out to extend and develop the application of peripheral magnometry method to investigate environmental pollution and metal contaminants resulted from vehicle traffic in some areas of Tehran with heavy traffic. The leaves of Platanus Orientalis in the inland areas of Chitgar Park as a clean area and Azadi Square and Geisha Bridge as crowded areas were collected. Magnetic components such as natural magnetic residual, mass magnetic susceptibility, isothermal magnetic residual and saturated induction magnetic residual were measured in the samples. The concentration of copper, iron, lead and cadmium was measured by mass spectrometry and the relationship between magnetic components and metals was investigated. The results showed that the highest value of susceptibility and magnetic residual of leaf saturation was associated with heavier traffic of vehicles in Azadi and Geisha. The study of the composition of particles in the Chitgar showed a combination of hard ferromagnetic minerals such as hematite with high concentration and soft ferromagnetic minerals with low concentration, which are the result of the activities of the peripheral industries and traffic in Tehran-Karaj highway. The presence of soft magnetic minerals in both Azadi and Geisha regions was higher than Chitgar. In Azadi, the size of particles was larger and the mineral behavior indicated a combination of the presence of soft and hard minerals, while the size of particle was smaller in Geisha.

The application of kriging in the field of environment is focused on four main sections: mapping of precipitation, quantitative and qualitative status of groundwater, quantitative and qualitative evaluation of surface water and spatial forecasting of air quality (Hanefi Bayraktar,2005; Nas, 2009; Chen et al., 2016; Sharma et al., 2017; Yang et al., 2018).
Different types of kriging have been developed, but the most popular of these is ordinary kriging (OK). The most important disadvantages of OK is that it assumes the mean of modelled variables to be constant and the prediction is only based on the spatial structure of the studied points. In addition, the effect of important parameters does not take into account the estimation result, and in some cases the predicted values by OK may be out of the studied range (Mukhopadhyay et al., 2017; Montero and Matthew, 2015). To overcome these problems, the universal kriging and blind kriging have been developed. Blind kriging (BK) is a more complete version of universal kriging and is based on Bayesian variable selection technique which is complicated and takes a lot of time to identify the unknown mean function.
In this research, due to the complexity of the Bayesian computation, we will combine the regression technique with blind kriging as the unknown mean function is defined by variable selection techniques that are used in linear regression analysis such as forward selection, backward elimination, and step-wise regression. The residuals at the known points are calculated from the difference of the observed values and the values of the selected function. Then the residual mean at the unknown point is solved by OK method.
Tajan River is one of the most important rivers in Mazandaran province. This permanent river is about 140 kilometers long and originates from the mountainous area on the northern slopes of Alborz Range. Tajan River runs to the plains carrying the water from various tributaries in the mountains and then drains into the Caspian Sea. Dodangeh, Lajim, Chahardangeh and Zarem rivers are the most important branches of it. The area of Tajan River watershed in the Aldehil region (before entering the Caspian Sea) is 4700 square kilometers. There are different land uses including agriculture, aquaculture, dam construction and industrial activities around the river. The necessity to perform a systematic study of the river water quality is, therefore, a need and of prime importance.
The objective of this study is to evaluate water quality parameters in different sites on Tajan River. This study also attempts to propose a modified kriging method, in which the unknown mean function is defined by using linear regression in order to simplify the computations of blind kriging. The proposed method and ordinary kriging were used to model the spatial variability of heavy metals and water quality index and their results were compared. This case study may be counted as an initial effort to study the spatial variability of water quality parameters, which may have many practical implications

The water sampling took place in spring of the year 2018. Sampling sites were selected based on natural conditions and accessibility to Tajan River by taking into account natural and human impacts, including river sub-branches, changes in the polluting sources such as agricultural lands, residential centers, existing industries, etc. Sampling sites were named 1 to 10 from downstream (near the Caspian Sea) to upstream (the Shahidrajae Dam). Water samples were collected by Nansen bottles and transferred into 1-liter bottles previously cleaned by nitric acid (0.1 N). The temperature, pH, electrical conductivity (EC), total dissolved solids (TDS), dissolved oxygen (DO), redox potential (Eh), and turbidity (Turb) of each water sample were directly measured at the sampling points. The biochemical oxygen demand (BOD5) was determined by the Winkler Azide method and chemical oxygen demand (COD) by the dichromate reflux method. Phosphate (PO4-P) and Nitrate nitrogen (NO3-N) were analyzed by spectrophotometric method, and fecal coliform (Fcoli) were measured by multiple tube method.
For measuring metals, each water sample was filtered through Whatman filter (0.45 μm) and about 5 mL of HNO3 (0.1 N) was added to the samples (until pH<2). Then, the samples were stored in the refrigerator at a temperature below 2 °C until being transferred to the laboratory. The measured elements included Arsenic (As), Barium (Ba), Calcium (Ca), Cobalt (Co), Chromium (Cr), Copper (Cu), Iron (Fe), Nickel (Ni), Lead (Pb) and Thorium (Th). Metal measurements were done by inductively coupled plasma optical emission spectrometry (ICP-OES). Analysis of the samples was done based on the instructions recommended by (APHA, 2005).
All mathematical and statistical computations were made using EXCEL 2016, SPSS 22 and ArcGIS 4.10.1.
The proposed method and ordinary kriging method were applied to interpole and predict IRWQI, Fe, Ni, Co, Th, Ba, As, Pb and Cr and their results were compared.

IRWQI had low values in midstream (sites 5, 6 and 7) near Sari City and its value increases by moving away from the city to show an improvement in the water quality status. This is due to the effect of anthropogenic pollutants in Sari city which are negatively associated with the water quality index. The average range of pH was from 7.6 to 8.11. pH values of water samples indicated that it was slightly alkaline. The relatively higher pH in water are probably due to the presence of pollution and eutrophication status. The mean values for Eh ranged from 142 mV to 201 mV. The water of Tajan River (excepting in site 1 near the sea) is non-saline.
The mean function for each variable (IRWQI, Fe, Ni, Co, Th, Ba, As, Pb and Cr) was created by multiple linear regression. The coefficient of determination (R2) and adjusted R2 were used to check regression model adequacy. t-Test and residual analysis were used in testing the regression coefficients verifying of the applicability of the regression model. The coefficient of determination (R2) ,Coefficient of Variance (C.V.) and Root Mean Square Error (RMSE) were used to evaluate the results of the ordinary kriging and proposed method. The proposed method showed 8.8 percent improvement for Cr, 34 for Co, 56 for Pb, 62 for As, 44 for Ba and 169 for IRWQI. In addition, both methods for prediction of thorium and nickel were almost identical. While ordinary kriging performance was good in predicting iron and better than the proposed kriging, because for parameters whose correlation is strong with distance and spatial distribution, ordinary kriging method can work well in modeling them. the mean concentration of elements in the water followed the following pattern: Ca> Fe > Ba > Ni > As > Cr > Cu >Th> Co > pb. The mean concentration of elements (Co, Cr, Ni, Cu, pb and Th) demonstrate a similar pattern with a decreasing trend from the upstream to the downstream. This will strongly show a similar process and origin. while the mean concentration of Ba and As was increased at various sites from the upstream to the downstream.

Development of aquaculture and the necessity to comply with environmental standards reveal the need to study the potential adverse effects of this industry. One of the most devastating effects of aquaculture would be water pollution caused by the discharge of untreated effluent from fish farms into the host aquatic ecosystems. Accordingly, the present study was performed to assess the contamination caused by trout farms on water quality of Haraz River in northern Iran.

For this purpose, a total number of 24 physical and chemical water quality parameters were sampled from 15 stations over a one-year period based on the standard methods. The maps of Topography, Geology, Hydrology, Soil, Land use, and access roads of the study area were prepared and studied. Furthermore, the pollutant sources, including fish farming pools, agricultural fields, residential areas, industries, and hot water mineral springs, located within the boundaries of the study area were also identified.  

The results showed that concentration of BOD, NO3-, and PO4 at the stations 7 and 10 was very high. The reason for this can be proximity of several fish farms close to each other. . Moreover, the concentration of DO in the mentioned stations showed a substantial decline that may be due to increased consumption of oxygen due to proximity of multiple fish farms in these stations.

Overall, the results confirm the considerable impact of fish farms on the quality of surface water resources in the study area. This highlights the need to take the necessary management measues to control pollutants from the industry in the from of environmental guidelines and regulations.

In this study, the shape, structure and elemental composition of the deposited particles on the leaves of Ulmus Carpinifolia, Platanus Orientalis, and Robinia Pseudacasia in Azadi and Chitgar areas in Tehran was investigated through individual particles analysis with SEM-EDX. The properties of 128 particles were analyzed through SEM-EDX. Thirty-four elements were identified in all the samples. The diameter of particles in Azadi was greater than Chitgar. The average diameter of particles was 7.26 microns. The average diameter of particles was 7.51 microns in Platanus Orientalis, 6.88 microns in Ulmus Carpinifolia, and 4.42 microns in Robinia Pseudacasia, respectively. The diameter of 45% of the particles was smaller than 2.5, 31% of the particles between 2.5 to 10, and 23% of the particles bigger than 10 microns. The distribution of metal particle size in all samples showed that the average diameter of the metal particles was 14.05 microns and the diameter of 14.28% of the particles was below 2.5, 42.85% between 2.5 to 10, and 42.85% was above 10 microns. Various structures of the elements were observed in the areas. Particles morphology showed that the origin of particles production is natural resources and they are man-made. In general, the average diameter of deposited particles on Platanus Orientalis and Ulmus Carpinifolia was more than those on Robinia Pseudacasia. Moreover, the particles diameter distribution showed that in Platanus Orientalis and Ulmus Carpinifolia particles are deposited with different sizes while in Robinia Pseudacasia there is less variation in particles size.