فهرست مطالب بهمن یارقلی

In the current research, with the aim of identifying the most effective techniques to reduce actual water use (Eta) to help restore the lakes of Urmia, Tashk-Bakhtegan, Fars, and Shadgan Wetland in Khuzestan, monitoring was carried out in the crop year 2021-2022 by applying planting techniques at the level of farmers' fields and orchards. In this research, 55, 17, and 18 farms and orchards were considered from Urmia Lake, Tashk-Bakhtegan and Maron-Jarhari basins, respectively. The results showed that the application of all techniques reduced irrigation water by an average of 24.6%, increased yield by an average of 18.3% and water productivity by an average of 60.4% for all the three catchments. However, not all these techniques were effective in reducing the amount of ETa. Farm monitoring showed that the techniques based on "accurate scheduling based on soil and plant indexes along with the modification and optimal management of the existing irrigation system" were able to reduce ETa by an average of 15.5% and improving the efficiency of water productivity (WPET) by an average of 40% in all the three basins. Therefore, the most effective techniques in Urmia Lake basin were use of two-way furrows of rows of trees in surface irrigation and planning drip irrigation based on soil and plant indexes in row crops and trees, which reduced ETa by 18%. Also, there was 21%, reduction in ETa by making irrigation plots under tree shades for pomegranate and pistachio in the Tashk-Bakhtgan Basin, and 13% reduction by making basins around the shading surface of palm trees along with palm leaf mulch, and 14 % reduction by the water flow cutback management method in the strip surface irrigation in the Maron-Jarahi Basin. These were considered as the most important techniques. Finally, it can be stated that paying attention to monitoring techniques at the level of a basin with local participation and promoting them can be effective in protecting the region's ecosystem while establishing sustainable agriculture.

Wetlands are highly beneficial to human societies due to their positive environmental functions, direct and indirect functions, as well as their value as an asset. It has led to an increase in the attention given to their restoration and maintenance in different societies. Shadgan Wetland contains fresh-salty, and brackish water, and approximately 900 million cubic meters of Jarahi water resources enter Shadgean every year. The wetland is at risk of serious harm as a result of the developmental activities occurring around it, which are causing pollutants to enter the wetland and reducing the quantity of fresh water coming in. A number of factors contribute to the destruction of this wetland, including over-exploitation from its water resources, the discharge of urban waste within its limits, the fragmentation of the wetland as a result of road construction, the construction of stations to increase the pressure on electricity, gas and oil pipelines, as well as effluents from industries such as bread making, alcohol production, sugarcane cultivation and industry. The economic value of wetlands and climate regulation, flood prevention, protection of plant and animal diversity, beauty and inherent visual attractions of wetlands, tourist attractions, as well as creating an opportunity for migratory birds to nest and a place for scientific research are among the most important considerations in the design of a wetlands. The development of water resources schemes and the regulation of river flows are often recognized as the most serious threats to the ecological sustainability of rivers and wetlands.

This study attempts to determine the change in water salinity of Shadegan wetland in the last five decades using the electrical conductivity index due to the importance of Shadegan wetland in various ways. Finally, a relationship has been established between the area and the salinity of this significant wetland. Also, by using electrical conductivity data from 23 stations in the lagoon and with the help of satellite images and remote sensing techniques and interpolation methods (IDW), the changes of this index in the mentioned period were investigated, leading to a mathematical relationship.

According to the research results, upstream human activities, especially dam constructions and agricultural development projects, have had a great impact on the quantity and quality of the wetland. With climate change and drought, these effects have intensified, resulting in a reduction of the wetland level as well as an increase in the salinity of the wetland water. These changes can be observed both in terms of their temporal and spatial dimensions. Consequently, the results show the trend of increasing salinity from the southern parts to the north and also the greater manifestation of the increase in salinity in the southern parts due to the decrease in the incoming fresh water flow (more than twice). According to the results, there are three salinity levels in the wetland: saline, brackish water, and super salinity, and a salinity increase is observed in all three zones The present results and equations are used as an achievement by water and environment managers and they can estimate the EC of water in key and indicator stations and finally at the level of the wetland by measuring the size of the wetland using different technologies. So over time, the levels and zones of saline and super salinity have expanded, and the levels of brackish water have decreased. It is expected that this process will continue over time, resulting in the sea salt water advancing towards the wetland and increasing the amount of salinity within it.

According to this study, based on the relationship between salinity and the level of the wetland, as well as the water area of the wetland, it is possible to estimate its salinity in three zones. By measuring the salinity of water at several key stations within each of the three zones, the wetland's water level can be estimated. In monitoring, managing, and qualitatively protecting the wetland and consequently its species, this equation and its relationships can play an important role.

The purpose of this study was to determine the influence of different levels of cadmium concentration of the soil on accumulation of cadmium in various parts of seven different types of common vegetable crops: lettuce, spearmint, coriander, cress, onion, parsley and leeks. A factorial experiment in a completely randomized design with three replicates and three treatments was conducted. The treatments included three levels of cadmium concentration in soil 50 mg.kg-1, 100 mg.kg-1 and control with no cadmium. The soil used in this study was prepared by using a sieve with a 2mm mesh and adding nitrate cadmium plastic pots were employed to cultivate vegetables. At the end of the growing season, samples were prepared from different parts of the plants to measure cadmium concentration. The SPSS software was employed to analyze the data. The results showed that cadmium concentrations were higher than 0.05 to 0.1 mg/kg and 0.2 mg/kg, the rates that Institute of Standards and Industrial Research of Iran and FAO/WHO, respectively, announced as safe for human consumption. Cadmium was found in stems: of lettuce, spearmint, coriander, cress, onion, parsley and leeks from highest to lowest; in leaves: of lettuce, cress, onion, coriander, parsley, spearmint and leeks; from highest to lowest; and in; roots: of cress, lettuce, spearmint, coriander, parsley, onion and leeks from highest to lowest. The results indicated that the highest amount of cadmium concentration among the different parts of the vegetables was founded in lettuce stem (6.8 mg/kg) and the lowest amount in leek root (0.77 mg/kg), both higher than what has determined as safe for human consumption. All treatments were considered as unsafe treatment while no sign of toxicity was found in control sample. The high accumulation of cadmium in lettuce, cress and onion, the vegetables that are consumed more, is critical due to their potential to accumulate this element in their leaves. These vegetables cannot be safe for consumption by human if is grown in soils with high concentration of cadmium.

Due to the high consumption of water in agriculture, considerable drainage is produced annually. Currently, a significant volume of drainages (almost 3 BCM) is entered into the Khuzestan province environment without any beneficial use, resulting soil and water contamination. On the other hand, according to Iran's water problems, the quality conservation of water resources and the use of unconventional water resources are essential, especially drainage quality management, and applying them to agriculture and the environment.

This research is carried out to evaluate the efficiency of biological filters with different beds for the treatment of agricultural drainage in Mirza Kooch Khan and Amirkabir Agro-Industry fields in Khuzestan province of Iran during the spring and summer of 2019. The research aims to reduce drainage contamination when discharged into the environment and drainage reuse in agriculture. In this research, the effect of four different types of biological filter including wheat straw, rice husk, cotton stalk, and wood sawdust as the main factor and three retention time of 2, 5 and 10 days as the secondary factor are investigated. The quality factors monitored include turbidity, EC (as a salinity index), total nitrogen (TN), total phosphorus (TP), and BOD.

Analysis of variance demonstrates a significant difference between the mentioned treatments in terms of the studied parameters (at the level of 1%), except for pH. According to the results, the highest average refinement of qualitative factors based on filter type for turbidity equals 37.87% and relates to the treatment of cotton stalk. For EC, TN, TP, and BOD equal to 9.23%, 49.60%, 46.50%, and 97.59%, respectively, and relate to wood sawdust. Moreover, the average of the highest percentage of pollution reduction for the investigated factors is related to the retention time of 10 days, which for turbidity, EC, TN, TP, and BOD are equivalent to 56.79%, 12.97%, 66.51%, 53.49%, and 80.20%, respectively.

Observed results indicate that wood sawdust treatment has a relatively better performance than other treatments. This issue is important since the existence and abundance of this material in the country is high. In addition, due to the importance and effectiveness of hydraulic retention time in treating, it has a direct relationship with efficiency of treating. However, the increase in efficiency from the retention time of 2 days to 5 days is more significant than the increase of retention time from 5 days to 10 days, which can be considered an important factor in selecting the retention time based on pollutants concentration in the drainage. As a result, based on the concentration of input and output quality parameters, it is suggested to use a wood sawdust filter with a 5-day retention time due to its proper performance and being more economical in terms of volume and dimensions of the system.

The water crisis is one of the major environmental challenges. Due to the problem of cheaper and faster desalination of seawater than seawater, in order to supply water, it has become increasingly important. Desalination using biological methods involves the use of different species of plants, microorganisms, algae or a combination of them, which can be effective in reducing water salinity. The aim of this study was to investigate the desalination of saline waters using seaweed. The present study was conducted to investigate the desalination of brine waters using seaweed. The present study was performed as a factorial study in a completely randomized design. The two-way ANOVA analysis of variance was performed with two main treatments including two types of algae (Dunaliella salina and Cholorella vulgaris) and two sub-treatments including 2 salinity levels (50 and 70 milliseconds per centimeter). The experiment was performed under controlled laboratory conditions and during the incubation period, electrical conductivity was measured daily. The results showed that the uptake of chlorine, sodium and bicarbonate was significantly different in Dunaliella salina and Cholorella vulgaris algae. Decreased by 3 mmHg Based on the research results, it seems that the reduction of salt absorption in algae using salt is in algal metabolism and their growth and reproduction.

Due to the critical conditions of Lake Urmia, improving irrigation methods as one the effective solutions is considered by the country's water managers. The present study was conducted to evaluate the effect of improving agricultural activities with the aim of reducing water consumption on greenhouse gas emissions in the provinces of East Azerbaijan (five cities) and West Azerbaijan (six cities) during the autumn and spring crop season on tomato, wheat, and sugar beet crops. The results of autumn wheat cultivation showed that the amount of CO2 produced in East and West Azerbaijan decreased by 22 and 28%, respectively, compared to the control treatment. Carbon footprint in East and West Azerbaijan in the treatment compared to the control shows a decrease of 39 and 35%, respectively. The results of spring cultivation for tomatoes showed that the amount of CO2 produced in the treatment was reduced by 25% compared to the control So that this amount decreased from 3925 in the control to 2917 kg/ha in the treatment. The carbon footprint of tomato production also showed that it was equal to 0.04 in the treatment and equal to 0.06 in the control (Kg CO2/kg) and had a decrease of about 33%. For sugar beet in West Azerbaijan province, the amount of CO2 produced and carbon footprint in the treatment decreased by 11.7% and 28.5%, respectively, compared to the control.

The growing need for food and the increase in agricultural production, and consequently the increasing demand for water on the one hand, and the harmful environmental effects of agricultural drainage water on natural ecosystems and receptive water resources on the other, have led the world to look for methods and techniques that, along with reducing the harmful and adverse consequences of drainage water, make it possible to reuse them to meet part of human needs. In many areas facing water shortages for irrigation, drainage water is used to meet the crop's water requirement. Due to high volume and special quality, agricultural drainage water have a high potential for pollution in the environment, especially water resources. According to water shortage in Iran and population growth and increasing water needs in various uses, planning for the protection and quality management of water resources and optimal use of unconventional water, especially agricultural drainage water as alternative water resources has become more necessary.

For this purpose, the present study investigated the efficiency of a natural reed bed on a real scale in qualitative treatment of incoming drainage water of Khuzestan sugarcane during a period of one year (2010-2011). According to the trend of qualitative changes and wastewater treatment stages at the reed bed level, the length of the reed bed was divided into three parts, namely three stations ST1, ST2, and ST3 with a length and width of 3.5*1.2 hectares, respectively. The efficiency of the natural reed bed was evaluated by measuring parameters such as BOD, COD, PO4, and TP.

The results of the T-Test showed that there are significant differences in terms of BOD values between ST0-ST1, ST0-ST2, ST0-ST3, ST1-ST2, ST1-ST3, and ST2-ST3 study stations. The highest difference in BOD was observed between ST0 and ST3 stations equal to 6.96 mg/l. In addition, the lowest difference in BOD was detected between ST0 and ST1 equal to 1.73 mg/l. At the ST3 station, which is the farthest from the entry point, the highest percentage of BOD removal was obtained. There was a significant difference of 1% for COD between study stations. The largest difference in COD was observed between ST0 and ST3 stations equal to 9.62 mg/L followed by ST1-ST3 stations equal to 7.12 mg/L. There was also a significant difference of 1% levels in PO4 and TP of study stations and the highest difference in PO4 and TP with 0.2724 and 0.3790 mg/l, respectively, between stations. ST0-ST3 was observed. The results showed that the performance of the reed in eliminating the studied parameters was very good and acceptable. The removal efficiency of BOD, COD, PO4, and TP to the last station was noticeable and acceptable in all four seasons. Under different retention times (1.26, 1.10, 1.30, and 1.60 days), the removal percentage of BOD, COD, PO4, and TP was significant in ST1, ST2, and ST3 stations and with increasing the distance from the entry point, of the drain, the reed efficiency increased. Considering the different performances of the three stations in improving the quality of drainage and considering the efficiency target above 50% of all organic matter and phosphorus compounds, the ST2 station can be assumed as the optimal limit in terms of efficiency and cost.

In general, this system can be used as an efficient system in reducing common drainage water pollutants to the level of drainage water treatment standards and acceptable reduction of BOD, COD, PO4, and TP parameters of agricultural drainage water and improving the quality of this drainage water for discharge to surface and groundwater and also reuse for irrigation in agricultural fields.

Chromium is one of the heavy and toxic metals for microorganisms, animals, and plants, which the use of the sources that contain them may lead to serious environmental pollutants. High concentrations of chromium are considered a stress factor for plants that can affect plants' physiological and biochemical properties as a growth-limiting factor. Due to an active chromite mine in the Forumad area of ​​Mayamey city, Semnan province, this research is to determine the status of chromium contamination in water resources, the soil of the region, and plant samples. Regarding the mentioned issue and for the identification, simultaneously sampling of all water resources in the region, including wells, springs, and aqueducts, are implemented. Besides the qualitative analysis and determination of ions (anions and cations), the total chromium concentration is investigated in the Soil and Water Research Institute. The results indicate pollution centers in the areas of Forumad, Pole Abrisham, Estarband, Kalateh-ye Sadat. A sampling of crops, horticulture, and medicinal plants in the region showed that the amount of chromium adsorption in pepper as a national index product of the region was less than the allowable limitation (less than 1 mg/kg), and the initial concerns were largely resolved. The absorption of total chromium in pistachio and pear crops is also within the allowable range, considered in the region's cultivation program. Since the absorption of chromium in sesame seeds, wheat, alfalfa, figs, and some crops is higher than the allowable level, incentive policies should be implemented to improve the cultivation pattern and replace it with contaminated crops. Contamination of soil sources in the region with chromium was investigated at 32 points. The results showed that almost all soil samples are more contaminated with chromium (range 386-142 mg/kg). The results showed that the concentration of total chromium in the four samples sent from Forumad and the Pole Abrisham before treatment was 123.5, 107.2, 127, and 110.6 μg / l after treatment of zero, 6.7, zero, and 4.2 μg / l, which indicates the use of reverse osmosis in drinking water.

the present study investigated the efficiency of natural reeds on a real scale in qualitative treatment of incoming drainage water of Khuzestan sugarcane during a period of one year (2010-2011). The efficiency of natural reeds was evaluated by measuring parameters such as NO3, NO2, NH4 and TN. T-test results on NO3, NO2, NH4 and TN factors showed that there is a significant difference between ST0-ST1, ST0-ST2, ST0-ST3, ST1-ST2, ST1-ST3, ST2-ST3 stations (1%). The highest mean difference in NO3, NO2, NH4 and TN was observed between ST0-ST3 stations. At ST3 station, which has the greatest distance from the entry point, the highest removal efficiency was obtained for each of the nitrogen compounds. The mean removal for NO3 factor in the outlet drainage water in ST1, ST2 and ST3 stations was 23, 50 and 64% lower than the initial amount in the inlet drainage water, respectively. At ST3 station with an average of 0.02 mg / l, the lowest amount of NO2 was observed. The use of natural reeds reduced NH4 compared to the initial level. This decrease was greater at ST2 and ST3 stations and ST3 station had the largest decrease (70, 68, 67 and 68% in all four seasons of spring, summer, autumn and winter, respectively). The trend of TN changes compared to the initial rate was similar to the trend of NH4 changes, but the rate of TN decrease at ST3 station was more severe and reached the lowest possible value compared to ST1 and ST2 stations. The results showed a significant effect of reed application in reducing TP in this distance from the entry point. In different stations, with increasing distance from the entry point, the effect of retention time (1.26, 1.10, 1.30

The electrical conductivity parameters are directly related to the water salinity, and its variation trend indicates the variation trend in water resources salinity. Regarding Iran's water resources, there is a concern that due to climate change and drought in recent years, as well as increased water consumption compared to the past, the quality of these resources in terms of salinity is growing. In this study, the Mankendall trend analysis test by eliminating the discharge background effect (noise), which is a documented method in trend analysis on time series without a specific statistical distribution. In order to find the variation time-trend, the electrical conductivity (EC) parameter was used in 20 hydrometric stations located on different rivers of Iran. In selecting hydrometric stations, climatic, hydrological, land use index and different geographical conditions have been considered as effective factors. The results of this test provide a clearer and more citationable perspective of the salinity process. These results indicate the increasing trend of salinity in Moshiran (Darreh River), Samian (Qarasu River), Ahvaz (Karun River), Doab Nosard (Sirvan River), Maraveh Tappeh (Atrak River) and Nozarabad (Nekaroud River) stations and (30% of selected stations). Among control strategies and reduce this trend are observance of rivers and wetlands, balancing and reducing withdrawal from groundwater resources, implementation of watershed management projects, drainage management and prevent the development of agriculture.

In the face of increasing urban wastewater and the fact that the country's water resources are not only limited but also declining, increasing water use efficiency and reuse of municipal wastewater is inevitable. This study was conducted to investigate the use of municipal wastewater on yield, yield components and water use efficiency in forage maize with two factors: a) Use of wastewater in three levels (1- well water (W), 2- One to one mixture of well water and wastewater (50 50) and 3- Wastewater (WW) b) Management of traditional low irrigation at four levels (normal irrigation (100% irrigation requirement)) and low irrigation at 40, 60 and 80% levels of water requirement) in the form of a randomized complete block design with 12 treatments and three replications in the field of Marvdasht municipal wastewater refinery plant in 2018. Statistical indicators such as maximum error, coefficient of determination, mean square root of the error, modeling efficiency and residual coefficient were used to quantitatively evaluate the functions. Plant susceptibility coefficient (Ky) for total dry matter in three stages of vegetation, flowering and grain ripening were 0.38, 0.52 and 0.63, respectively, and it was found that the most sensitive stage of corn growth to water deficiency is the stage of grain ripening. Analysis of interactive effects showed that the highest total dry matter yield in vegetative and flowering stages and grain yield in grain growth stage were 7260, 9857 and 3158 kg/ha in WW-FI treatment (complete irrigation with wastewater) and the lowest yield with the values of 5052, 6069 and 1508 kg/ha were obtained in W-DI60 treatment (60% low irrigation with well water). The results showed that the use of wastewater in low traditional irrigation conditions is useful for forage maize and can be recommended.

Hydrodynamic prediction and simulation of rivers’ qualitative parameters is very important for determining the rate of loading of pollutants and their manner of transmission in aquatic ecosystems, in relation to rivers’ self-purification capacity. From the beginning of human life, rivers and surface waters have always been considered essential because of the need for water for living purposes. Cities and industrial and agricultural centers, in fact entire civilizations, arose near the rivers in order to use sources of water. However, by developing industry and technology, human beings started destroying nature. Knowledge of the quality of water resources is one of the most important requirements in the planning and development of water resources and their conservation and control. Hence, in order to ensure the monitoring and management of the quality of this natural resource, some methods can be used that entail the least cost and time to attain these objectives. To develop these studies, sampling and environmental tests for water qualitative parameters were initially conducted. For performing this step, six stations were determined for monitoring in the basin of the Balikhlouchai. The parameters considered were then measured and the results were compared with existing standards. The purpose of conducting this study is to route the pollution of Balikhlochai River, establishing a relationship between the results of two quantitative and qualitative simulated hydrodynamic models (HEC-RAS and WASP) and comparing the results with statistical indices (mean absolute error, root mean square error, Relative volume error, and Nash–Sutcliffe model efficiency coefficient). Given their self-purification and self-regulation capabilities, rivers in normal situations can undertake the natural load of pollution imposed by the environment and solve them. In situations in which pollution has human origins and the load is more than the river’s carrying capacity, this will be associated with destruction, and the death of river ecosystems. The reasons for the increase in pollution load are the entry of surface runoff from the rainfall into the river, washing of various pesticides and organic fertilizers, phosphate and nitrate due to drainage of agricultural land, and the organic load entering the urban and rural. Wastewater into the river along the route is the source of food for algae and, as a result, increases the pollution burden and reduces the health of the river. Calibration and validation of the model were performed based on samples taken from six monitoring stations during 2015-2016. According to the validation results, MAE, RMSE, RE and NSE statistical indices for DO were 0.04, 7.2, 4.7 and 0.84, respectively, and 0.07, 8.2, 5.2 and 0.81 for the river flow rate, respectively, representing the optimal and reliable results of the output of simulation models. The results obtained from statistical indices showed that the simulation of the research variables was well performed, the simulation results were reliable and both models have good performance in predicting water quality. Due to the increasing population and growth of various kinds of pollution, the qualitative conditions of the rivers and aquifers become worse in the field of surface water. According to the results of the models’ output, the river discharge along the route ranged from 1.2 to 0.3 m³/s and DO ranged from 7.5 to 3.5 mg/l, indicating a severe reduction in the river flow rate and DO. Comparing these results gives a more accurate analysis of the pollution process in the Balkhlohai River; as the river's downstream is lowered, the loading rate of the pollutants is increased. So, the river is naturally unable to reduce pollutants and return the river to its normal state. It happens because both velocity of the water flow and the depth of the river are reduced. Therefore the amount of water mixing in the river decreases, as well as the amount of dissolved oxygen in the river due to reduced mixing. So, the pollution load and pollution of the river increases. Studying the pollution process in Balikhlochai River indicated that river pollution was due to the entry of urban wastewater and runoff from agricultural drainage-water into the basin, as well as the severe reduction in river self-purification capacity and Eutrophication phenomenon. The decade's prediction shows that if the measures needed to manage the current status of river water quality are not met, the river's health is compromised and should be stepped up to restore the river. The results indicate that the river downstream from the point of view of quality management should be prioritized and the study results can be used in determining the strategies for coping with pollution and promoting management in the Basin of Balikhlochai River.

Groundwater resources are the second largest fresh water resources in the world and almost one third of the world population depend on these resources. These resources that are accessible through wells, canals and springs are utilized for different uses and in return they receive ample amount of domestic, industrial and agricultural waste waters. Assessment of aquifer vulnerability is very useful in land uses management and development, groundwater quality monitoring and prevention of water resources pollution.

In current study, DRASTIC model in conjunction with GIS is used for zoning Ardabil plain vulnerability and aquifer quality data processing and analysis is performed accordingly by these tools.
It also uses the measurement results of nitrate in groundwater, DRASTIC model is calibrated to the Ardabil plain.

The results of the drastic model show that the vulnerability of the Ardabil plain aquifer is more in the moderate vulnerability group. According to the findings of this study, moderate vulnerability is 39.3%, low vulnerability is 32.4% and high vulnerability is 21.1%, very low vulnerability is 6% and very high vulnerability is 1.1%, respectively.

The level of contaminations of Ardabil aquifer was observed to be high and the result of this research revealed that its potential to be polluted is high. Therefore, given the importance of the groundwater resources in the region, it is necessary to establish a management plan to optimize the usage of this valuable resource.

Today, development of irrigated lands is faced with limited resources. With the increased water scarcity, the importance of using municipal, industrial and agricultural wastewater is increasing. This study was conducted on laboratory scale to investigate the efficiency of some bioadsorbents (rice husks, wheat straw, woodchips and cotton stalks) in removing nitrate from aqueous solutions and their application as bio filters in agricultural wastewater treatment.

First, absorbents were well-washed with distilled water, dried and crushed by the mill, and percolated through a standard sieve mesh 30 to obtain uniform powder from the absorbent samples. In order to prepare the required concentrations, nitrate solution was added to the distilled water with certain amount of potassium nitrate. For each bioadsorber, a spectrophotometer was used to measure the extent of nitrate removal at contact periods in order to determine the periods required to reach equilibrium, the optimum pH values of adsorbents, and the suitable concentrations of adsorbents.

Results indicated the significant differences at the confidence level of 99% among the adsorbents in removing nitrate and these adsobents significantly reduced the nitrate in aquous soloutions. In the four adsorbents, the nitrate removal rates at the studied contact periods (5, 10, 20, 30, 60 and 90 minute) were statistically significant at the confidence level of 99%. Results from determining the suitable concentrations of the four studied adsorbents to reach the maximum efficiency showed that 1 g in 40 ml solution was the most suitable concentration. Moreover, reduction in the adsorbents amounts reduced their efficiencies. Study of isotherm models indicated that for all the studied adsorbents correlation coefficients in Langmuir’s isotherm model were higher compared to Friedrich isotherm model. Therefore, Langmuir isotherm model was more suitable for predicting nitrate removal from aqueous solutions by bioadsorbents. Discussion and

Plant absorbers significantly reduce the amount of nitrate in aqueous solution. In this study, Langmuir model can be used as an adsorption isotherm.for adsorption of the bioadsorbents.

Exploring the homogenous regions for site specific management is important, especially in the areas under different anthropogenic activities. This was investigated using multi-way analysis including Factor Analysis, Hierarchical Clustering Analysis and k means in the areas under long-term wastewater irrigation over a period of more than 40 years, in Shahre Rey, south of Tehran. By using Factor Analysis model, eight factors as eight geochemical groups were extracted to explain approximately 60% of the total variance related to 37 soil physicochemical properties. The most important groups included the nutrient elements (OM, OC and N), micronutrients (Mn and B), soil water adsorption capacity (Clay, Silt, Sand and CEC), salinity and osmotic pressure (EC, OP and TDS) and sodification (SAR and Na). The maximum values of Cophenet and Silhouette coefficients were equal to 0.77 and 0.83, respectively, dictating the selection of the average linkage approach in Hierarchical Clustering Analysis and three clusters in the k-average method with 19, 24 and 34 mapping units. The Thiessen Polygons method in GIS was applied to separate the geochemical groups in the form of mapping units. This output, which was, in fact, the combination of multi-way models and its visual representation in GIS under separated mapping units of study area, could present suitable management activities for the areas under each cluster.

Water crisis due to high demand of water in agricultural sector is becoming more evident on day by day basis, hence the use of unconventional water resources, especially drained agricultural water is gaining importance. In this investigation the efficacy of four types of biological filters namely: wheat straw, rice husk, cotton stalk and wood sawdust for improving the quality of agricultural drainage water with respect to factors like, salinity, acidity, nitrate, calcium, magnesium, sodium, phosphate, sulphate, pH, TDS and TSS was investigated under a pilot scale study. Analysis of variance showed that no statistically significant difference between different treatments in terms of the impact on the parameters studied, except for nitrates. Based on the results of this study, all the drainage water filters were effective in improving the quality of wastewater for agriculture, so any of them can be used to this end, since these types of filters are available in all region of the country. The results showed that in terms of eutrophication of water resources, when wastewater discharged to surface water resources, the sawdust and cotton stalk filters, the removed nitrate,was 63.23 and 60.12 percent and the removed phosphate was 20 and 20.7 percent respectively and were superior to other filters. Based on the qualitative analysis of wastewater output of the studied biofilters, and comparing it with standards pertaining to maximum allowable limit for application in agricultural fields, it can be concluded that about 260 million Square meters of drainage water available from irrigation network in Moghan.irrigation network is suitable for production of wheat, barley and cotton under different planting patterns in the region.

Environmental pollution due to the accumulation of heavy metals in soil and their subsequent transfer to crops is a global concern that arises from improper application of industrial wastewaters. This study was conducted to investigate the effects of different levels of soil Cd on its accumulation rate in the various organs of four common crops in Iran (namely, wheat, spinach, cucumber, and carrot). The experiment was performed in a factorial design with random blocks including 3 treatments with 0 (control), 50, and 100 mg/kg.soil in 4 replicates. Soil was collected from the farm belonging to the Research Institute for Plant and Seed Breeding (Karaj) and filtered twice using 2-mm sieves before Cadmium Nitrate (Cd(NO3)2) was added and completely mixed. Crops were planted in plastic pots 40 cm in diameter and 60 cm in height. The water demand was determined using the Jenman Mantite method. At the end of the growing season, samples were taken from various organs of the crops and their Cd concentrations were measured. The results revealed a direct relationship between Cd accumulation and Cd concentration in the root region. All the treatments other than the control exhibited Cd concentrations higher than the standard limits for human consumption. Cadmium accumulation in the different organs of the crops exhibited the following orders: Root: Cucumber

Keywords: : Cadmium, Crop Uptake, Industiral Wastewater}

In this study, the effects of long term use of urban wastewater (over 40 years) on soil salt content and related parameters were evaluated in the lands south of Tehran. For this analysis, Kriging methods were tested. According to the suitable model indices, Ordinary Kriging (OK) was suitable for pH, Clay, Na, Mg2 and sodium adsorption ratio (SAR) interpolation; Log-normal Kriging (log-normal K) was suitable for soil EC and Cl-; DK was suitable for soil Ca2. In this study, Na, Cl- and sodium adsorption ratio (SAR) variables with the highest nugget-to-sill ratio showed most affected by extrinsic variations (long term irrigation with wastewater). In spite of wastewater irrigation, results showed low amounts for EC of soils (less than half the critical limit) attributed to good leaching through high and permanent water bodies. However, Na and sodium adsorption ratio (SAR) with amounts higher than critical limit showed need to management measures like gypsum application. Heavy soil of area is a reinforcing factor in sodicity trend related to clay percent higher than 25, so sodicity risk treats total area of study region.

Environmental pollution by heavy metals is a growing global concern. Most heavy metals accumulate in the top soil and in the long term, increased concentrations in the soil results in increased absorption and accumulation in plants. The usual concentration of cadmium in the soil is 0.001-2.4 mg/kg of dry soil. The level of absorption and accumulation in plants depends on the type of plant, tissue make-up of the plant and physical and chemical characteristics of the soil. There is a deficit of information on the amounts of absorption and accumulation of heavy metals at different tomato growth stages. This study was conducted to analyze the impact of the level of cadmium concentration in soil on its absorption and accumulation at different stages of tomato growth using factorial experimentation in a completely randomized design with three repetitions. The variables were three Cd concentrations (control treatment with no Cd; soil with 50 mg kg-1 Cd; soil with 50 mg kg-1 Cd; soil with 50 mg kg-1 Cd). The soil samples were collected from 400 ha of farmland at the Seed and Plant Improvement Institute in Karaj, Iran. They were sifted twice using 2 mm mesh and the treatments were prepared by adding cadmium nitrate to the soil to make homogeneous mixtures. The experiments were carried out in plastic cylinders 120 cm in length and 85 cm in diameter. The depth of the solution soil was sampled hourly and tomato organs were sampled at different growth stages to record the cadmium absorption rate. SPSS software was used to perform an analysis of variance of the data and the Duncan multiple range test was used to perform a comparison of means (P ≤ 0.05 and P≤ 0.01). Results showed that cumulative cadmium concentration differs in the tissues of the leaf, root, leg, fruit and peel in decreasing order. A negligible amount of the total cadmium added to the soil was absorbed by the plant. Total cadmium absorbed in the cellular colonies of the tomato plant in the control treatment, soil with 50 ppm added Cd, and soil with 100 ppm added Cd were 0.0384, 0.564 and 0.678 g, respectively. The results indicate a direct relationship between Cd accumulation and Cd concentration in the root region. A comparison of the outcomes indicated that increasing the cadmium concentration resulted in a reduction of tomato growth and, especially, the production rate. A 20-35% decrease in production rate was seen in 50-00 ppm cadmium exposure compared to the control. These results show that strong decreases in cadmium concentrations in the solution soil did not decrease the absorption rate of cadmium at various growth stages of the tomato.

The main source of heavy metals in soil is the use of urban and industrial waste water, synthetic phosphate fertilizers, sludge from sewage treatment plants. Most heavy metals accumulate in the top soil and in the long term, their increased concentration in the soil and accumulation in the plants. The quantity or level of absorption in plants, depends not only on the concentration levels of the metals in the physical and chemical composition of the soil, but also varies in different parts of the plant type. Several studies have been conducted on the use of waste water and sewage, carrying heavy metals, for griculture; however information regarding amount of absorption and accumulation of heavy metals in various parts of different crops and plant types, is limited. This study has been conducted with the objective of analyzing the impact of various levels of cadmium concentration in soil on the quantity of its absorption and accumulation in various parts of five different types of cucurbits, commonly used in Iran. The experiments were carried out in a factorial experiment in completely randomized design, with three repetitions. The factors includes Cd concentration in 4 levels (control treatment, without adding Cd, soil with 50 mg kg-1 Cd, soil with 50 mg kg-1 Cd, soil with 50 mg kg-1 Cd and irrigation water with 0.5 molar EDTA). And plants species (five summer crops) at the end of agriculture season, samples from different organs of species have been collected to measure the magnitude of Cadmium accumulated in them. With SPSS software, variance analysis of the collected data was performed, and comparison of means was performed by Duncan multiple range test (P ≤ 0.05 and P≤ 0.01). The obtained results indicate a direct relation between Cd accumulation and Cd concentration in root region. Adding 0.5 molar EDTA to irrigation water causes more than 50 percent increase in Cd accumulation in treatment of 50 ppm Cd. Also the results show (except in control treatment) that Cd concentration is in excess of limit for human consumption.