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مرکز اطلاعات علمی SID1
اسکوپوس
دانشگاه غیر انتفاعی مهر اروند
ریسرچگیت
strs
Author(s): 

mehrabi h.

Issue Info: 
  • Year: 

    2019
  • Volume: 

    9
  • Issue: 

    2
  • Pages: 

    15-27
Measures: 
  • Citations: 

    0
  • Views: 

    848
  • Downloads: 

    242
Abstract: 

Management and exploitation in mines require a continuous and relatively smooth surface of the mineral grades. While assessing the various mineral elements, the scattered exploratory cavities are irregularly excavated. Producing a continuous surface from measured data requires interpolation methods. Several factors, including the characteristics of the data, affect the efficiency of the interpolation methods. For this reason, the efficiency of different methods in various cases is inconsistence, and choosing the appropriate interpolation method is also challenging. Interpolation methods can be categorized into two groups of mesh-based and meshless methods. Despite the efficiency and capabilities of meshless methods, they have a fundamental shortcoming due to the fixed size of the support domain. On the one hand, the distribution of exploratory cavities in mines is usually irregular, and in some areas, it is very dense, and in others, it is very sparse. On the other hand, the grade values of minerals at the surface of the region can be very variable with high changes. Conventional interpolation methods do not have sufficient efficiency and flexibility in confronting these two aforementioned issues. In this study, a precise, reliable, and flexible method is developed for interpolation of minerals through integrating the moving least squares and recursive least squares methods. In the proposed method for crack detection, the residuals statistical test of least squares computations is used. In this method, for the central point, a continuity threshold (non-continuity) is determined based on the standard deviation of field values, so that points with crack are revealed and removed from the calculation of the value of the central point. Moreover, the size of the support domain is determined dynamically based on the recursive property of the method. In this method, an individual radius for the support domain is assigned to each central point according to the values and distributions of the surrounding field points. The dynamic size of the support domain allows a precise and reliable estimation of polynomial coefficients and the values of the central points. The efficiency of the proposed method is evaluated by applying it to simulated data as well as comparing it with the results of conventional interpolation methods on real mineral data. The results of the simulation data indicate the ability of the proposed method to reveal the non-continuity and fractures of surfaces with determining the dynamics size of the support domain based on the data structure. To compare the results of the proposed method with conventional interpolation methods including LPI, IDW, Kriging, and RBF, the root mean square error (RMSE), mean and median of errors are used. In this way, in addition to the overall accuracy of each method, the distribution of errors is also determined. The RMSE, mean and median errors of the proposed method, using the 10-fold cross-validation method for CHROMIUM (Cr), are 28. 020, 0. 2. 201 and 2. 874, respectively, and for iron (Fe) are 1. 074, 0. 017 and 0. 094, respectively. Comparison of these results with conventional interpolation methods indicates the efficiency of the proposed method for both groups of high concentration and significant changes in the values and low concentration and almost uniform level of values. The results indicate the ability of the proposed method in detecting the jumps and non-continuity in the support domain and removal of some field points within the dynamic process, lead to a significant increase in the efficiency of the method compared to conventional methods.

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Journal: 

GEOSCIENCES

Issue Info: 
  • Year: 

    2015
  • Volume: 

    25
  • Issue: 

    97
  • Pages: 

    237-250
Measures: 
  • Citations: 

    0
  • Views: 

    1002
  • Downloads: 

    343
Abstract: 

In this research the catchment of the Sarbaz river, SE Iran, has been studied to determine sediment provenance and its possible pollution potential. 30 sediment samples collected from the riverbed were analyzed for major and trace elements, using combined XRF and AAS methods. Based on major and trace element data and identification charts the sediments are identified to be of litharenite composition. Quartz-rich sedimentary and intermediate igneous origin and island arc tectonic setting is proposed for the sediments, mainly inferred from discrimination diagrams. Regarding the hazardous potential of metals and metalloids, As, Cd, Co, Cr, Cu, Fe, Mn, Hg, Ni, Pb, Se, V and Zn were studied from 30 locations. Pb, Cd and As concentrations measured respectively in 7, 10 and 20 locations are more than concentrations of the same elements in the world riverbeds. In this research, the polluted sediments were evaluated using the geo-accumulation index (Igeo). Based on this index, Cd, Pb, Zn and Cu show some degrees of pollution, while other elements are evaluated to be less pollutant. Statistic analysis show strong correlation between studied elements. Volcanic activity in north of the Makran zone can readily justify the common origin of the contaminants in the catchment of the Sarbaz river. CHROMIUM is most probably originated from the nearby Makran ophiolites. It is concluded that geological factors have mainly been the controlling factors for the sediment pollution in the Sarbaz catchment.

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Issue Info: 
  • Year: 

    2010
  • Volume: 

    4
  • Issue: 

    2
  • Pages: 

    321-332
Measures: 
  • Citations: 

    1821
  • Views: 

    1008114
  • Downloads: 

    713123
Abstract: 

The spatial and temporal distribution of heavy metals in water, sediment and fish (dry weight basis) of Buriganga River, Bangladesh were determined by atomic absorption spectrophotometer. In water concentration of Pb, Cd, Ni, Cu and Cr varied seasonally and spatially from 58.17 to 72.45μg/L, 7.08 to 12.33mg/L, 7.15 to 10.32mg/L, 107.38 to 201.29mg/L and 489.27 to 645.26mg/L, respectively. CHROMIUM was the most abundant in the water of Balughat during pre-monsoon, whereas, Cd was the most scarce in the water of Shawaryghat during monsoon. The sediment also showed spatial and temporal variation of Pb, Cd, Ni, Cu and Cr ranged from 64.71 to 77.13 mg/kg, 2.36 to 4.25 mg/kg, 147.06 to 258.17 mg/kg, 21.75 to 32.54 mg/kg and 118.63 to 218.39 mg/kg, respectively. Among all the metals studied in sediment, Ni was the highest at Foridabad during pre-monsoon and Cd was the lowest at Shawaryghat during monsoon. In six species of fish studied, the concentration of Pb, Cd, Ni, Cu and Cr varied seasonally from 8.03 to 13.52 mg/kg, 0.73 to 1.25 mg/kg, 8.25 to 11.21 mg/kg, 3.36 to 6.34 mg/kg and 5.27 to 7.38 mg/kg, respectively. Of the five metals studied Pb concentration was the highest in Gudusia chapra during monsoon, in contrast, Cd concentration was the lowest in Cirrhinus reba during post-monsoon. Some of the heavy metals’ concentrations are higher than the recommended value, which suggest that the Buriganga is to a certain extent a heavy metal polluted river and the water, sediment and fish are not completely safe for health.

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گارگاه ها آموزشی
Issue Info: 
  • Year: 

    2020
  • Volume: 

    12
  • Issue: 

    1
  • Pages: 

    61-73
Measures: 
  • Citations: 

    0
  • Views: 

    375
  • Downloads: 

    154
Abstract: 

Introduction:Cereals are the main sources of calorie in poultry diets and corn is the most common cereal in poultry feed formulations;however,in some countries such as Iran,corn is mainly imported from other countries,In addition to import-associated problems,high volatility of corn price has recently resulted in a marked tendency between Iranian poultry producers to use other alternative grains in their formulations,Among the other cereals,wheat,rye,and barley are the most frequently used grains in poultry diets from which,barley is believed to be a great alternative for corn due to its high productivity and good compatibility to the climatic conditions of the country,Barley is one of the most abundant grains raised in various areas of Iran and could be included in the formulations instead of corn,However,the extreme variability in nutrient contents observed within and between different barley varieties makes it difficult to achieve a good nutrient balance in barley-containing diets,The energy content of feedstuffs is a topic of high importance for poultry nutritionists since birds regulate their feed intake based on dietary energy concentration,There are different methods to determine metabolizable energy (AME) content of feedstuffs including energy balance bioassay (excreta or ileal digesta-based methods),referring to the standard tables describing feedstuff compositions (NRC and FEEDSTUFF tables),indirect AME determination using near-infrared spectroscopy (NIRS) technique and the use of multivariate prediction equations,Energy balance bioassay is the most reliable but time-consuming and expensive method while nutritionists need relatively simpler and faster methods for accurate feed AME estimation,On the other hand,contents of standard feed-describing tables are mean values obtained in a variety of previous studies performed under climatic conditions differing fairly from those of Iran,Most researchers agree that the values presented in the tables are not reliable and generalizable due to the extensive variability of feed types and varieties,During the last decades,various AME-predicting regression equations have been suggested for different feedstuffs but the data used for exploiting the equations have been obtained from animals and feeds genetically different from the modern commercial strains and varieties,Therefore,updating the equations using animals and feeds of today seems to be necessary,This study aimed at developing prediction equations for AME of the most producing Iranian barley varieties, Materials and Methods:Three trials were conducted to develop regression predictive equations for apparent metabolizable energy (AME) of some of the most producing Iranian barley varieties in broiler chicken diets and to compare the outputs of the equations with the AMEn values estimated by infra-red spectrophotometry (NIRS) method as well as with the values published by the national research council (NRC,1994),In the first experiment,10 different barley varieties were analyzed for proximate composition,Then,in the second experiment,total tract AMEn values were determined for all of the barley varieties using 10 or 24-d-old broiler chickens and CHROMIUM oxide as an indigestible marker,Results of the two first trials were used to develop AMEn-predicting equations using SPSS software and "enter" procedure,To verify the accuracies of the predictive equations,the third trial was conducted using 400 broiler chicks in a completely randomized design consisting of five treatments with four replicates of 20 birds each,The AMEn content of the barley variety used in the third experiment was estimated according to the following five procedures:1) The AMEn recommended by NRC (1994);2) The AMEn predicted using the equation suggested by NRC (1994);3) The AMEn values directly estimated in the balance trial (trial 2);4) The AMEn values predicted by the equations developed in the 2nd trial;and 5) The AMEn estimated using NIRS method, Results and Discussion:The equations obtained for 10 and 24-d-old broilers were:AMEn= 407,87*EE+27,27*NFE and AMEn= 271*EE + 33*NFE,respectively,The results showed that the AMEn values exploited from the equations developed in the energy balance assay produced the closest performance to that of the AMEn values estimated directly during the same trial, Conclusion:According to our findings,predictive equations can be used for accurate estimating of barley AMEn value for broiler diets formulation,In addition,our results showed that the old AMEn values and AMEn-predicting equations published by NRC (1994) and FEEDSTUFF (2014) are not accurate at least for Iranian barley varieties evaluated in the present study,

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Issue Info: 
  • Year: 

    2020
  • Volume: 

    12
  • Issue: 

    2 (25)
  • Pages: 

    157-176
Measures: 
  • Citations: 

    0
  • Views: 

    558
  • Downloads: 

    138
Abstract: 

Introduction Ophiolites are a set of oceanic rocks with different appearance and mineralogy in the world's largest orogenic belt, from the Alpine to the Himalayas. The ophiolites of Iran are also located in this belt. Among ophiolites in Iran, the Nehbandan Ophiolitic Complex in the east of the country is of great importance. The complete ophiolitic sequence consists of two sets. The first is the crust sequence, gabbro, diabase and basalt, and the second is a mantle sequence or peridotites, both of which are sequences in the Nehbandan Ophiolitic Complex. The main purpose of this research study is mantle section. There are three study areas, located near the city of Nehbandan: Kalateh-Shahpori, Qadam Gah peridotites that are about 30 km northwest of the city of Nehbandan near the Chahar Farsang village and the third area is located between the Khansharaf village and Nasfandeh Kuh area that is 10 km east of Nehbandan. Materials and methods In this lithological and mineralogical research study, thin and polished sections were prepared from samples. The thin sections were analyzed by polarizing OLYMPUS microscope BH-2 and the polished sections were analyzed by the OLYMPUS BX-60 reflecting microscope. A CAMECA SX100 electron probe microanalyzer was used to determine the chemical composition of the minerals in samples. The analytical condition include 15 kV and 20 nA rays with periods of 10 to 30 seconds at peaks for different minerals that are analyzed at the electron probe microanalysis center in the University Of Toulouse, France. The stoichiometry of minerals was used to calculate the amount of Fe3+ for access to the structural formula of minerals (Droop, 1987. Results and discussion In terms of petrography, the Kalateh Shahpori peridotites are of the Harzburgite type and the Nasfandeh Kuh peridotites are of the Lherzolite type. The Qadam Gah peridotites are both geographically and petrographically indicative of the state of transition between the two other regions. The mineralogy of the Kalateh Shahpori peridotites is composed of olivine (Fo91), orthopyroxene (En90 Fs9), and the Cr-spinel is of the high Cr type. The Nasfandeh Kuh peridotites have olivine minerals that are Chrysolite (Fo89), orthopyroxene (En89 Fs9) and (En86 Fs10), clinopyroxene (En46 Fs5 Wo49) and, the Cr-spinel is of the high Al type. The Qadam Gah peridotites are composed of olivine (Fo90), orthopyroxene (En89 Fs9. 5), clinopyroxene (En47 Fs3 Wo50) and, the Cr-spinel is of the medium Cr type. According to geochemical data and petrogenesis, the Kalateh Shahpori harzburgites are of the supra-subduction zone type in the forearc basin. The Nasfandeh Kuh Lherzolites are of the middle-oceanic type. The Lherzolites of Qadam Gah have the same characteristics of both regions in terms of the formation environment. However, they are much more similar to the middle-oceanic peridotites. The degree of partial melting of the peridotite has a direct relationship with the Cr content and it has an inverse relationship with the Al2O3 content in the CHROMIUM-spinel of the peridotite (Hellebrand et al., 2001). Probably, these lherzolites formed due to the re-fertilization of harzburgites (Monsef et al., 2018). Accordingly, Kalateh-Shahpori harzburgites with 20% partial melting are of high-grade, and the Nasfandeh Kuh Lherzolites with 5% partial melting are of the low grade type. The herzolites of the Qadam Gah are approximately 11% partial melting and are located between the Kalateh Shahpori peridotites and the Nasfandeh Kuh peridotites. The high degree of melting in the Harzburgites may indicate their remelting in the fluid environment because the hydrosis condition increases the degree of partial melting of peridotite (Hirose and Kawamoto, 1995). The Cr# in Cr-spinel, and the Mg# in olivine of the peridotites indicate the presence of at least 3 types of peridotites in the Nehbandan Ophiolitic Complex. According to mineralogy, petrography, geochemistry, and petrogenesis studies of the peridotites in the Nehbandan ophiolitic complex, it is recommended to explore possible chromite deposits, high melting and supra-subduction harzburgite zones such as Kalateh Shahpori harzburgites which should be considered to be the first priority. Then the peridotites of transition regions such as Qadam Gah should be at second priority and finally the low melting middle-oceanic lherzolites such as the Nasfandeh Kuh shuld be considered to be the third priority.

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Author(s): 

AFSHARI A. | KHADEMI H. | AYOUBI SH.

Issue Info: 
  • Year: 

    2015
  • Volume: 

    29
  • Issue: 

    1
  • Pages: 

    151-163
Measures: 
  • Citations: 

    0
  • Views: 

    771
  • Downloads: 

    329
Abstract: 

Introduction: Heavy metals are types of elements naturally present in soil or enter into soil as a result of human activities. The most important route of exposure to heavy metals is daily intake of food. Crops grown in contaminated soil (due to mining activities, industrial operations and agriculture) may contain high concentrations of heavy metals. Also closeness to cities and industrial centers can have a great influence on the accumulation of heavy metals to agricultural products grown in the region. The study aimed to determine the concentration of heavy metals in soil and agricultural products around urban and industrial areas of Zanjan province (North West of Iran) and consumption hazard probability. Materials and Methods: Soil (75 samples of soil from a depth of 0 to 10 cm) and plant (101 samples) samples, in the summer 2011, were randomly taken from industrial areas as follow: tomatoes (Lycoper sicumesculentum M), wheat seed (Triticum vulgare), barley seeds (Hordeum vulgare), alfalfa shoots (Medicago sativaL.), potato tubers (Solanumtuberosum L.), apple fruit, vegetables and fruits such as Dill (Aniethum graveolensL.), leek (Allium porrum L.), Gardencress (Barbara verna L.) and basil (Ocimum basilicum L.). Plant sampleswere then washed with distilled water, oven dried for48 hours at a temperature of 70 ´C until constant weight was attained and then they digested using 2 M hydrochloric acid (HCl) and nitric acid digestion in 5 M. Concentrations of heavy metals in the soil and crops were determined by atomic absorption spectrometry. DTPAextraction of metals by Lindsay and Norvell (1978) method and sequential extraction method by Tessier et al. (1979) were performed. Statistical analysis was accomplished using the software SPSS 16.0 and the comparisonof mean values was done using the Duncan test at the 5% level of significance.Results and Discussion: The magnitude of variations for total copper was from 11.5 to 352.5 (average 52.4), zinc was from 96.3 to 1353.8 (average 264.8), lead was between 40.0 and 470.0 (average 105.7), nickel rangedfrom 12.8 to 77.0 (average 46.7) and CHROMIUM varied from 10.0 to 49.5 (average 21.7) mg kg-1. DTPAextracted heavy metals for copper varied from 1.50 to 21.23, averaging 4.47, zinc from 0.57 to 76.50 averaging 23.15, lead from 2.43 to 63.38 averaging 16.81 and nickel from 0.28 to 2.32 averaging 1.20 mg kg-1. Chemicalchanges in the different fractions were as follows: Cu (residual>bounded to organic matter>bounded to Fe-Mnoxides>bounded to carbonate>exchangeable fraction), Zn and Ni (residual>bounded to Fe-Mn oxides>bounded to carbonate>bounded to organic matter>exchangeable fraction,) and Pb (residual>bounded to Fe Mn oxides>bounded to organic matter>bounded to carbonate>exchangeable fraction). The concentration of heavy metals in plant parts were high with respect to studied location. The highest amounts of Zn (Garden cress), Pb (Dill), Cu (Leek), Ni (Basil) and Cr (Basil), respectively were found to be 150.25, 41.25, 23.13, 6.46 and 3.47mg kg-1 and the minimum amounts of the metals studied were found in fruits, wheat and barley grains. The to talamount of metals in plants were as follow (Zn>>Pb>Cu>Ni>Cr). Bioaccumulation factor (BAF) of metalsin plants were as Zn=Cu>Pb>>Cr>Ni. Hazard probability (HQ) in cancerous diseases for each element (except Pb) in both children and adults was less than unit. HQ content of Pb was much higher than the unit and for children and adults 9.07 and 6.94, respectively showing high contribution of Pb contamination of crops that hreatens the consumer health in that location. The total amount of risk (THQ) in children was higher than that inadults.Conclusions: The results obtained in this study indicate that an urgent attention is required for consumerproducts related to public health, especially vegetables grown in the studied regions. Toxic effects of heavy metals have many deleterious effects which are more pronounced over time. With conventional monitoring of food quality produced in farms and presented in markets, excessive accumulation of heavy metals entering in to the human food chain can be prevented. Also, we can change the risk potential of heavy metals in the region by growing vegetables which accumulate heavy metals.

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strs
Issue Info: 
  • Year: 

    2020
  • Volume: 

    11
  • Issue: 

    4
  • Pages: 

    451-462
Measures: 
  • Citations: 

    0
  • Views: 

    323
  • Downloads: 

    154
Abstract: 

Introduction: Cereals are the major part of a poultry diet and primary sources of feed energy Because of the worldwide high cost of corn, the use of barley and wheat grain in broiler diets has become more appealing. However, the use of barley in poultry diets because of its high content of non-starch polysaccharides (NSP) is limited. NSP increased intestinal viscosity, reduced litter quality and poor productive performance. Most of the adverse effects of barley in poultry feed have been attributed to the content of β-glucans. The NSP fraction of the cereal protects lipids, starch, and protein, thereby compromising the access of digestive enzymes to dietary components. Therefore, the processing of barley grain to remove anti-nutritional factors and improve its nutrient bioavailability before including it in the diets of one-stomach animals is beneficial. However, information concerning the effect of electron beam radiation on nutritional and anti-nutritional components of barley grain are scarce. Therefore, this study was carried out to evaluate the effects of electron beam radiation on the chemical composition and metabolizable energy of barley grain. Materials and Methods: The barley samples (cultivar Fajr) were packed in nylon bags and exposed to electron beam irradiation (Rhodotron TT200 accelerator, IBA Co., Belgium) at the Yazd Radiation Processing Center (AEOI, Yazd Center, Iran) at doses of 10, 20, 30, and 40 kGy at room temperature. Chemical composition of the raw and electron beam irradiated barley grain was determined. In order to estimate AMEn Chicks were fed a standard broiler diet for a 15-d pre-experimental period and, after four h of feed deprivation, were randomly distributed into experimental groups (16 treatments, 4replicates and 5 birds in each) in such a way that all groups had a similar average weight. All diets were given in mash form with birds having free access to water and feed throughout the experiment. The basal diet used during the experimental period was based on corn and soybean meal as major ingredients. The raw and electron beam irradiated barley grain (as test ingredient) was included in the basal diet at levels of 7, 14, and 21% to form test diets. The 16 experimental diets, evaluated in a balance trial to determine the AMEn content which contained 0. 3% CHROMIUM oxide as an indigestible marker. The precision-fed cockerel assay of Sibbald was used for determining the TMEn of the raw and electron beam irradiated barley grain. The birds were housed in individual metabolism cages, following a period of 24 h without feed, 30 g of the different ground barley samples were fed by intubation to 20 (4 per treatment) adult cockerels (Rhode island reds). At the same time, another 4 cockerels were deprived of feed to estimate the endogenous energy losses. Total excreta over the following 48-h period were dried and ground for subsequent analyses, Roosters were assigned to treatments at random. Results and Discussion: The results showed that percentage of dry matter, crude protein, ether extract, ash, β-glucan, ADF, and starch of barley grain were not affected by radiation. However, electron beam irradiation in all doses significantly decreased (P<0. 05) the NDF of samples compared to raw barley grain. The AMEn of barley was calculated by extrapolation of the linear regression equation to a 100% of barley inclusion. These equations indicated that with increasing dose of irradiation, AMEn of barley increased. The AMEn value of raw and irradiated barley at doses of 10, 20, 30 and 40 kGy were 2593. 80, 2628. 30, 2663. 10, 2730. 70 and 2795 kcal/kg, respectively. The electron beam irradiation numerically increased (P>0. 05) AME, AMEn, TME and TMEn of barley grain in cockerels at doses above 20 kGy. Previous studies using gamma or electron irradiation show a reduction in anti-nutrient content of canola meal, barley, and cottonseed meal and an improvement in their utilization increase in broilers. Gamma and electron radiation can denature proteins, decrease starch crystallinity and increase digestibility of barley and canola meal. Therefore, increased AMEn and TMEn of barley grain were expected in this experiment. Conclusion: The present study showed that electron beam irradiation reduced NDF and increased AMEn and TMEn of barley grain. It seems that radiation is an effective processing method for improving the nutritive value of barley, but more experiment is needed to evaluate radiation.

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Author(s): 

TAKI SAEED | Shirud Isa niko

Issue Info: 
  • Year: 

    2019
  • Volume: 

    8
  • Issue: 

    4 (30)
  • Pages: 

    37-47
Measures: 
  • Citations: 

    0
  • Views: 

    322
  • Downloads: 

    171
Abstract: 

-- permissive permissive permissive permissive permissive - U. S. EPA بد acceptable acceptable good - good good good (Schoeller, 1965) Si-Cl SH5 desirable desirable desirable desirable desirable desirable desirable desirable Iran 1053 permissive permissive permissive permissive - permissive permissive permissive WHO (2011) -- permissive permissive permissive permissive permissive - U. S. EPA Measured parameters indicated that according to the standards of World Health Organization (WHO, 2011) all the springs (except Katalom which is somewhat acidic) are in permissive and desirable limit in respect of total dissolved solids (TDS), electric conductivity and acidity (pH). BOD values also showed that due to wastewater pollution there are many aerobic microorganisms and organic materials in the water of Giash spring while in the other springs, this parameter is zero and so there is no microorganism. Electric conductivity rates in all springs are in permissive range, but in Kachanak spring exceeds it. Comparing the anions contents with that provided by WHO, indicated that anions also are in the permissive ranges. Bicarbonate content in Kachanak spring is higher than other springs and nitrate in the Giash spring is the highest. Comparing the major cations in 5 studied springs showed that the lowest sodium and potassium contents are in the Giash and the greatest in Katalom spring. The highest contents of both calcium and magnesium were in Kachanak but the lowest ones in Rishboraz Darreh and Giash respectively. Silicon amount in Katalom was the greatest and the lowest in Giash. It seems that the unusually high amount of silicon is due to mixing of magmatic hot water with groundwater. According to WHO all the cations are in permissive range. Metal index (MI) (Tamasi et al., 2004) and Heavy Metal Pollution Index (HPI) (Mohan et al., 1996) are indicators to determine the pollution extent in the water resources in respect of heavy metals. MI is used to evaluate the potability, and HPI is used to examine the effects of the heavy metal on human health. To determine these indices, 13 elements data including Ba, As, Cd, Cr, Pb, Ni, Mo, Zn, Se, Mn, Sb, V, Cu were used. In all the springs, calculated MI and HPI were in the permissive range, which suggests a lack of severe pollution in terms of heavy metals. Katalom and Kachanak springs have the highest, and Namak Darreh has the lowest indices values (table 2). Geothermal activities in the vicinity of Katalom, Sadat Shahr and Ramsar, presence of thermal springs (and mixing of their water with mentioned springs), old mining activities in Katalom and agriculture activities in the area are among the reasons for these high indices’ values in Katalom and Kachanak springs. Table 2-Calculated MI and HPI indices for the studied springs. Giash SH5 Namak Darreh SH4 Rishboraz Darreh SH3 Katalom SH2 Kachanak SH1 Spring name Index 0. 098 0. 082 0. 123 0. 449 0. 302 MI 0. 009 0. 0078 0. 0106 0. 026 0. 012 HPI 4-Conclusion Based on the interpretation and processing of the information obtained from chemical analysis and evaluation of physical parameters, results on the studied springs are as follow: Kachanak spring is of Si-HCO3 type, and the others are of Si-Cl type. Silicon contents are higher than other elements. Alkaline earth metals (Ca2+, Mg2+) are more than alkaline elements (Na+, K+) and anions of strong acids (SO2-4) are more than weak acids (HCO3-). Noncarbonated hardness exceeds 50%. According to Schoeller standard, Kachanak spring is in non-drinkable and bad classes concerning calcium and magnesium contents, respectively. In Katalom spring, pH value is out of the limit of Schoeller standard and calcium, and magnesium contents were bad and moderate respectively. In Rishboraz Darreh calcium and magnesium, parameters are in acceptable for emergency conditions and moderate classes, respectively. In Namak Darreh spring, calcium is in unsuitable class, and magnesium is in moderate one. Moreover, pH parameter is also lower than the defined limit in this classification. In Giash spring, only in respect of calcium parameters is unsuitable class. All the springs of the studied area are in a good or acceptable group concerning other parameters. According to the Iranian standard (1053), in Kachanak spring, total hardness (TH) is unsuitable in undesirable range but is permissive, in Rishboraz Darreh, Namak Darreh, and Giash springs, parameters are desirable. According to WHO (2011) and U. S Environmental Protection Agency (U. S. EPA), pH parameter of Katalom is out of permissive limit, but TDS and total alkalinity in all springs are in the permissive range. Also, MI and concentration of heavy metals such as nickel, arsenic, lead, CHROMIUM in Katalom spring are most significant among other springs.

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Issue Info: 
  • Year: 

    2015
  • Volume: 

    7
  • Issue: 

    1
  • Pages: 

    5-6
Measures: 
  • Citations: 

    0
  • Views: 

    1235
  • Downloads: 

    302
Abstract: 

Introduction:Heavy metals are the most toxic pollutants in aquatic ecosystems. This contamination can result from the release of heavy metal elements during alteration and weathering of ultramafic and mafic rocks (ophiolite zones). Among the important metals and pollutants in the ophiolite; CHROMIUM, cobalt, nickel, iron, magnesium, manganese, zinc and copper could be noted. Basically, a mass of serpentine consists of serpentine, amphibole, talc, chlorite, magnetite, and the remainder of olivine, pyroxene and spinel (Kil et al., 2010). In such areas, the prevailing cold climate, during the serpentinization, chloritization and epidotiization, the activity of the solvent, such as chloride, fluoride, carbonates, sulfide, sulfosalt would be able to import the elements such as magnesium and iron, copper and zinc into the soil and groundwater. The study area is located in northwestern Iran. This area is located in the northwest of the city of Khoy.Because of the proximity to the north and northwest Khoy plains with ophiolite rocks, the soil of this region could possibly show the potential of contamination with heavy metals. Due to the toxicity and disease of unauthorized grades of these elements in groundwater in the study area, this study is focused on the more contaminated groundwater of the areas.

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Issue Info: 
  • Year: 

    2018
  • Volume: 

    9
  • Issue: 

    2
  • Pages: 

    41-54
Measures: 
  • Citations: 

    0
  • Views: 

    342
  • Downloads: 

    159
Abstract: 

Introduction Contamination of soils with heavy metals is often resulted from human activities and phytoremediation is an effective and economic strategy to remove toxic metals from soils. Heavy metals are significant environmental pollutants, and their toxicity is a problem of increasing significance for ecological, evolutionary, nutritional and environmental reasons. The term ‘ ‘ heavy metals’ ’ refers to any metallic element that has a relatively high density greater than 4 g/cm3, or 5 times or more, greater than water and is toxic or poisonous even at low concentration. However, chemical properties of the heavy metals are the most influencing factors compared to their density. Heavy metals include lead (Pb), cadmium (Cd), nickel (Ni), cobalt (Co), iron (Fe), zinc (Zn), CHROMIUM (Cr), iron (Fe), arsenic (As), silver (Ag) and the platinum group elements. Plants experience oxidative stress upon exposure to heavy metals that leads to cellular damage. In addition, plants accumulate metal ions that disturb cellular ionic homeostasis. To minimize the detrimental effects of heavy metal exposure and their accumulation, plants have evolved detoxification mechanisms. Such mechanisms are mainly based on chelation and subcellular compartmentalization. Chelation of heavy metals is a ubiquitous detoxification strategy described in wide variety of plants. The aim of this study was to investigate the effect of different compounds to reduce the toxicity and accumulation of heavy metals in the planting bed is pinto beans. Materials & Methods In order to evaluate the effects of different growing substrates on reducing toxicity and phytoremediation bean (cv. Sadri) under heavy metals, a greenhouse experiment was conducted as a factorial for four heavy metals (Cd(NO3)2, Pb(NO3)2, Ni(NO3)2 and CuSO4) seperately, based on CRD design with three replications in Yasouj University, 2013. The first factor included of four levels of different growing substrates (control, compost, vermicompost and Populus sawdust) and the second factor included of two levels of heavy metals (heavy metals with 50 mg kg-1 soil concentration and control). Results & Discussion Analysis of variance showed that the effect of organic compounds and cadmium nitrate in the soil and their interactions on amounts of cadmium accumulation in roots, shoot and grain was statistically significant. Compost and vermicompost significantly increased cadmium. Vermicompost can be used to remove metals from contaminated soils used because it is linked with metals and increases nutrient uptake by providing. A cadmium concentration in shoot tissue was more than adequate at all levels of the leveas (0. 2-0. 05 mg/kg dry weight). Lead levels in the tissues of roots, shoots and seeds in all treatments were the detection limit. It seems that due to the low accumulation of lead in beans can be attributed to the low mobility of lead in soil and plant. Means comparison showed the highest accumulation of nickel in the root of the control (normal soil) with an average of 14. 45 mg/kg dry weight of roots and the lowest value of this attribute in use of poplar sawdust with an average of 11. 42 mg/kg root dry weight that using compost and vermicompost was not significantly different. Analysis of variance showed that the effect of organic compounds in soil, copper sulfate and their interactions on the amount of copper metal roots was significant. When the low copper concentration in soil, compost and vermicompost with the stabilization of copper available and disabling decrease copper absorption and accumulation by the plants, but the high concentration of copper in the soil, add compost, vermicompost and poplar sawdust will not be enough to stabilize all accessible copper. In this study, the use of poplar sawdust to accumulate the highest amount of copper in copper sulphate roots in levels zero and 50 mg per kg dry weight soil. Conclusion The results showed that the use of compost and vermicompost increased amounts of cadmium accumulation in shoot and root. On the other side, compost and Populus sawdust decreases the amount of nickel in the bean shoot and root. Also, the highest accumulation of copper in roots of beans was achived by application of the Populus sawdust and compost. Accumulation of heavy metals in roots far more than shoots and seeds. In general, the results of this study showed that due to low accumulation of heavy metals in the seed of bean and high absorption by the root and shoot, this plant is suitable for cultivation in contaminated areas and if possible leaving the roots and shoots is also appropriate for the purification.

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