186 research outputs found

    Assessment of resistance and non-resistance fractions of heavy metals concentration (Fe, Mn, Cr, Ni) in surface sediments from the southern of Caspian Sea of two stations (Tonekabon and Amirabad)

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    This study was conducted to determine some heavy metals (Fe, Mg, Cr, Ni) of surface sediment in the southern Caspian Sea during two seasons (Summer and Winter) in 2014-2015. 36 surface sediments samples (with triplicate) were collected at two stations (Tonekabon and Bandar Amirabad). All samples were analyzed using sequential extraction to indicate natural and anthropogenic sources. The results indicated that the percentage of non-resistance fraction in Tonekabon area were measured 3.5,45.0, 22.1 and 6.0 for Fe, Mg, Cr, Ni, respectively and in Amirabad area were 23.0,2.6,1.8 and 4.0, respectively. On the other hand, the percentage of resistance fraction values were obtained 96.5, 55.0, 77.9 and 94.0 in Tonekabon, and 77.0, 97.4, 98.2, and 96.0 in Amirabad region. The chemical speciation of Fe, Mg, Cr, Ni in most sampling stations were in the order of residual> oxidisableorganic > acid-reducible >exchangeable. The order of total concentration, non-resistance and resistance fraction were observed Fe>Mn>Ni>Cr, Mn>Fe>Ni>Cr and Fe>Mn>Ni>Cr, respectively. As a conclusion, results of total concentration, resistnace and non-resistance of Fe, Mn, Ni and Cr were lower than standard and earth shell (Igeo) in this area. This is shown that surface sediments of this area were not polluted with these heavy metals and bio available fraction provides little indication of potential interactions with the biotic components present in this environment

    The Environmental Effect on Spawning Time, Length at Maturity and Fecundity of Kutum (R u t i l u s f r i s i i k u t u m , Kamensky, 1901) in Southern Part of Caspian Sea, Iran

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    Fish sampling were carried out using beach seines during the fishing season from early October 2006 to mid April 2007. The gonadosomatic indexes (GSI) in range and average for female and male were 0.03 to 40.28 (5.70 ± 6.48) and 0.13 to 16.71 (3.39 ± 2.33), respectively. The GSI indicated that the reproductions of R. f. kutum were occurred during March-April, with the highest average value of 6.52 for males and of 17.00 for females in April. Fifty percent of length maturity (Lm50%) at FL = 37.78 cm was recorded. The absolute fecundity ranged from 15,723 for a three-year old to 130,737 eggs for an eight-year old female, with a mean of 60435 ± 24889. The relationship between fecundity (F) and fork length (cm) was represented by the formula: Fec. = 6616FL+25916. The von Bertalanffy growth parameters was: L∞=67.5cm, K=0.21 year-1, t0 =-0.10 for throw population of kutum. The maximum spawning migration into the rivers based on GSI occurred significantly in April but it may effects by environment of sea water layers. The results showed that the length at first maturity and fecundity of R. f. kutum is reduced in southern part of Caspian Sea

    Promotion and updating of laboratories database for Iran Fisheries Research Organization

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    Creating a database of affiliated laboratories of the institute is organized with the aim of integrating information related to laboratories of research centers and their subsidiaries. The main objective of conducting this project in this stage is to upgrade it, establish and running one software system based on up-to-date technology of networking. In this way, in addition to organizing the centers database, a periodic report on various aspects can be done which help for implementing appropriate monitoring and management. Generally, the items that are designed and upgraded for this system include: Portal, bank of information, advanced possibilities for inputting data, searching and reporting on laboratory equipment and materials, information about calibration and repair and expiration dates of chemical materials, expertise and capabilities of personnel, providing laboratory services of institutes and research centers, direct order collecting of experiments from inside and outside of the institute, exchanging information, new test methods and sharing of new ideas and professional proposals, organizing laboratory materials, and exchange of expensive chemical materials. The advantages of this system compared to the previous version is that comprehensive, precise and updated reports can be collected easily from the general information of research institutes and centers, reports of the number of lab experts with different educational levels in affiliated centers, awareness of numbers and status of the chemical materials in the laboratories of each center, and the significant and important point is about economizing equipment, chemical materials and on time calibration, in time repairing of equipment and providing laboratories tariff and other matters

    Determination of pollution condition in Babolroud River from viewpoint of pesticides and agrochemicals fertilizers

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    Babolroud River is one of the important rivers for fisheries and environmental aspect that locared in center part of Mazandaran province. The river has a span of 92 km starting from Albourz mountainous and end up at the southern part of Caspian Sea. This study was done for five months (3rd Feb. through 5th July, 2008) for the better understanding of pollution situation such as organophosphorous, organochlorine pesticides and agrochemical fertilizer that drainage from paddy fields and horticultures to the river. A total of three main sites for pesticides and plus five sub-sites for drainage were selected for observation in three different regions of the river (mountainous, plain and estuary). The organochlorine and organophosphorous pesticides measured by GC (ECD and TSD detectors) with US-EPA (508) and AOAC procedure and agrochemical fertilizer parameters were measured by ASTM method. The maximum concentrations of aldrin, lindane, heptachlor epoxyde, DDE and β- BHC (period 1), δ- BHC and endrin (peiod 2), heptachlor and DDT (period 3), α- BHC (period 3 & 4), dieldrin (period 4) were 6.02, 0.85, 0.51, 0.50, 0.22, 0.35, 0.23, 0.50, 0.46, 0.19 and 0.16 µg/l, respectively. The maximum concentrations of four components of organophosphorous such as Diazinon and Chlorpyrifos (period 1), Malathion (period 2), Azinphos methyl (period 3) were 1.36, 0.46, 0.44 and 2.56 µg/l, respectively. The maximum amounts of tree components of parameters of agrochemichals fertilizers indictor such as total nitrogen (period 2, sub-site 5), total phosphorus and orthophosphate (period 4, sub-site 5) and organo-phosphorus (period 3, sub-site 4) were 5990, 1290, 1220 and 336 µg/l, respectively. The maximum concentrations of organochlorine pesticides components in sediments of the river such as lindane (period 2, site 2), δ- BHC (period 1 site 3), α- endosulfan (period 1, site 2), endrin and heptachlor epoxide (period 2, site 2) and DDE (period 2, site 1) were 0.99 0.54, 0.29, 0.19 and 0.19 µg/l, respectively. The maximum concentrations of organochlorine pesticides components in fish tissue of the river such as endosulfan sulfate, lindane, endrin, δ- BHC and DDE were 0.32, 0.29 0.27, 0.25 and 0.21 µg/l, respectively

    The feasibility of creating a natural habitat for spawning, bony fish in the Caspian Sea in order to preserve biodiversity and genetic risk

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    The purpose of this study was to investigate the possibility of natural reproduction of indanger fish in the southern Caspian Sea in Tajan, Haraz,Sardabrood and Chalos rivers, and identify suitable habitats for this species in the study area as a genetic reserve.Sampling of physical and chemical parameters of water, macrobenthic invertebrates and fish fauna was conducted seasonaly in each rivers at selected stations from febrary 2010 during one year. Macrobenthic invertebrate sampling were used bySorber sampler and fish was collected by gill net and electroshocker set with a voltage of 1.7 A and 100-300 V. A total of 53 taxa of macrobenticinvertabrateshave been identified in the four mentioned rivers, in which Tajanriverconsisted of 47 taxa with highest richness.20 species of fish were determined in the studied rivers that 6 of them were non-native species.The results showed that the predominant identified fish species were native in the river. The fish species diversity increases as one moves from the headstream towards the estuaries of the two studied Sardabrud and Chalus rivers.The results of this study showed that the relative abundance of fish species resistant to pollution and hard environmental conditions were much more that sensitive species. physicochemical parameters of water such as; water temperature, DO, BOD5, pH, TSS, TDS, EC, turbidity, nutrients, biodiversity index such as Shanon index, EPT, HFBI, EPT/CHIR, nutrition functioning group and present or absent of fish species showed that there are significant decrease in water qualities from upstraem ratio to down stream (For example, in Tajan river water turbidity varied from 0 at station 1 to 333 NTU at station 6, Which is strongly influenced by sand workshops. As well as the activities of a significant impact of fish farming workshop on the Haraz river water quality). The minimum of HFBI index was 2.84 at station 1 and the maximum was recorded at station 5 with 6.01, and there is not any possibility to natural reproduction of migrated species that are dominant and indanger at downstream. Conditions for natural reproduction of this species in the rivers of srdabrood and Chalus there is to some. In Shahid- Rajaei dam the maximum relative abundance of fish species belonged to Capoeta capoeta, Luciobarbus capito and Squalius cephalus, respectively. These species have different age, length and weight stuctures at Shahid- Rajaei dam inhabitant, and the resourval of this dam and it,s upstream have been preparing auch a favorabile condition that seems there are potentioal of introductionand inhabitant of some of the Migratory and indanger fish species such as Barbels, Sturgeon, Alburnus chalcoides and etc. as genetic reserve for biodiversity preservation

    A study on environmental pollutants (Organochlorine pesticides (OCPs), heavy metals, hydrocarbons and surfactants) in the southern part of Caspian Sea

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    At the present study, the environmental pollutants such as organochlorine pesticides (OCPs), heavy metals, hydrocarbons and surfactants were done during 22 months (Sept. 2009 through May 2011) located in southern part of Caspian Sea with longitude and latitude 48°-54° N and 36°-39° E, respectively. The aims of this study were to determine the seasonal pollutants matters in water layers and bed sediments of eight transect (24 stations) and the results are as follow: The maximum seasonal percentage range of OCPs were detected in spring water samples from 10, 50, and 50m depths such as (DDD, δ-BHC, heptachlor epoxide, endrin aldehyde),(DDD) and (aldrin, β-endosulfan) compounds about 62.5, 75 and 100%, respectively. The maximum seasonal residues fluctuation of OCPs were determined in spring water samples from 10, 50, and 50m depths such as aldrin (Babolsar station), aldrin (Tonekabon station) and heptachlor epoxide (Astara station) compounds about 5.03, 3.08 and 31.43 µg/l, respectively. The maximum percentage range of OCPs were detected in sediments samples from 10, 50, and 50m depths such as aldrin and α-BHC (winter), α-BHC (summer and winter) and aldrin (summer) compounds about 100, 75 and 87.5%, respectively. The maximum residues fluctuation of OCPs were determined in sediments samples from 10, 50, and 50m depths such as α-BHC (summer in Nushahr station), α-BHC (summer in Sefidroud station) and α-BHC (winter in Tonekabon station) and compounds about 5.96, 3.77 and 3.07 µg/l, respectively. The fluctuation and distribution of Total Petroleum Hydrocarbons (TPHs) concentration in different water layers samples were reduced from summer>spring> fall > winter, respectively. Also this trend occurred for bed sediments and reduced from winter > summer, respectively. The mean concentrations of TPHs in water samples of all seasons, regions, depths and transects were less than maximum permissible concentration (MPC). In this research, a comparison of TPHs with EPA standards shown that the desile range organic (DRO) was close to EPA standards such as TPHs and also 95 percent of water data were less than MPC. But gasoline range organic (GRO) concentrations in all stations were less than the amount of EPA standard. A comparison of TPHs concentration in sediments shown that the concentration of all stations were less than of national research council (NRC) range except west part. The maximum annual mean concentrations of Hg and Pb elements were detected in surface station (50m) at Nushahr and Amirabad transects. The most water data of Cd, Pb and Hg elements in comparison with critical concentrations with Europe, the USA and Japan standards were less than amounts of those standards. The distribution and abundance of Cd, Pb, Hg and Ni elements in water samples were detected 98, 96, 77 and 6%, respectively less than the ISQGs (Interim marine sediment quality guidelines) standards. In sediments samples, the mean and maximum concentration of Hg element detected in winter in comparison with ISQGs standards was more. But the concentrations of Cd and Pb in sediments samples of all stations were low and less than of ISQGs standards. The maximum concentration of linear alkyl benzene sulfonate (LAS) from spring through winter in Anzali (spring), Tonekabon (summer), Anzali (fall) and Nushahr (winter) were 0.07, 0.45, 0.145 and 0.087 mg/l, respectively. The maximum concentrations of LSA were detected in spring and fall in west part and summer and winter in middle part. But the lower concentration was occurred in west of southern part of Caspian Sea. According to standards of surfactants and comparison with LAS concentration of this study were less than the critical points

    Rotating biological contactors : a review on main factors affecting performance

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    Rotating biological contactors (RBCs) constitute a very unique and superior alternative for biodegradable matter and nitrogen removal on account of their feasibility, simplicity of design and operation, short start-up, low land area requirement, low energy consumption, low operating and maintenance cost and treatment efficiency. The present review of RBCs focus on parameters that affect performance like rotational speed, organic and hydraulic loading rates, retention time, biofilm support media, staging, temperature, influent wastewater characteristics, biofilm characteristics, dissolved oxygen levels, effluent and solids recirculation, stepfeeding and medium submergence. Some RBCs scale-up and design considerations, operational problems and comparison with other wastewater treatment systems are also reported.Fundação para a Ciência e a Tecnologia (FCT

    Study on physico-chemical characteristics of water in the southern of Caspian Sea

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    In this study, the characteristics of physico-chemical parameters of water done in coastal part of the southern Caspian Sea during 2010-2011 (four seasons) in 8 transects (Astara, Anzali, Sefidrour, Tonkabon, Noshahr, Babolsar, Amirabad and Torkman). For measurement of water quality parameters, 480 samples were collected in different water layers by using of APHA standards methods. According to modeling and statistical methods was used multivariate for evaluation of factor analysis (MFA) in general groups and discriminant analysis (MDA) for spatial and temporal with water quality parameters. The statistical procedure of MFA was used for data reduction and finally six factors selected with about 80.48 percent of total variances related to them. The statistical procedures of MDA were used for the role of spatial and temporal of water quality parameters in different water layer. The function one gave eight parameters (pH, salinity, EC, DO, NO^3-, water temperature, NH^4+ and N^-total) affording more than 80, 67, 80, 77 and 71 % correct assignations (return to the same transects) in spatial analysis. In all transects during four seasons, function one gave five parameters (water temperature, salinity, EC, NO^2- and NH^4+) to afford 100, 100, 100, 97 and 97 % correct assignations in temporal analysis. The results showed that, the average amounts in light penetration layers during four seasons were for EC(15.04±0.18ms/cm), pH(8.38±0.01unit), salinity (10.31±0.16g/l), DO(5.67±0.09ml/l) and water temperature (18.28 ±0.72°C). The average amount of nutrients for parameters such as organic and inorganic phosphorus, total phosphorus, NO^2-, NO^3-, NH^4+, N^-Total and SiO_2 were 0.50±0.02, 0.32±0.01, 0.82±0.02, 1.76±0.10, 0.10±0.01, 1.51±0.10, 46.82±1.80 and 8.60±0.29µM, respectively. The average amounts in dark layers during four seasons were for EC (15.46±0.38ms/cm), pH (8.34±0.03unit), salinity (10.70±0.35g/l), DO (4.55±0.13ml/l) and water temperature (9.62 ±0.16°C). The average amount of nutrients for parameters such as organic and inorganic phosphorus, total phosphorus, NO^2-, NO^3-, NH^4+, N^-Total and SiO_2 were 0.54 ±0.05, 0.33 ±0.02, 0.87±0.06, 1.92±0.21 , 0.08± 0.01, 1.55±0.25, 45.10±3.25 and 10.05±0.62 µM, respectively. The average amounts of light penetration in all transects during four seasons 4.49±0.38 meters. The maximum light penetrations during spring, summer, fall and winter seasons were 9, 8, 8.20 and 7 meters, respectively. The maximum water temperatures in light and dark layers were 32.36 and 11.50°C. Also, the maximum differences about thermocline temperature during summer and fall seasons were 19.6°C and 10°C, respectively in southern part of Caspian Sea. Data in spatial analysis were not significant (p>0.05), it means if add or removed any transect did not change occurred. But in temporal analysis were significant (p<0.01), and it means no way remove any seasons for a research work on Caspian Sea in southern part. In those transects with 100m depth. Water temperature is only highly effective parameter between other parameters. In function 1 between 3 functions in transects with 100m depth water temperature with 60% variance was the main role and effective between different seasons in depth part were very high

    Proton Transfer, Hydrogen Bonding, and Disorder: Nitrogen Near-Edge X-ray Absorption Fine Structure and X-ray Photoelectron Spectroscopy of Bipyridine-Acid Salts and Co-crystals

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    The sensitivity of near-edge X-ray absorption fine structure (NEXAFS) spectroscopy to Brønsted donation and the protonation state of nitrogen in the solid state is investigated through a series of multicomponent bipyridine–acid systems alongside X-ray photoelectron spectroscopy (XPS) data. A large shift to high energy occurs for the 1s → 1π* resonance in the nitrogen K-edge NEXAFS with proton transfer from the acid to the bipyridine base molecule and allows assignment as a salt (C═NH+), with the peak ratio providing the stoichiometry of the types of nitrogen species present. A corresponding binding energy shift for C═NH+ is observed in the nitrogen XPS, clearly identifying protonation and formation of a salt. The similar magnitude shifts observed with both techniques relative to the unprotonated nitrogen of co-crystals (C═N) suggest that the chemical state (initial-state) effects dominate. Results from both techniques reveal the sensitivity to identify proton transfer, hydrogen bond disorder, and even the potential to distinguish variations in hydrogen bond length to nitrogen

    Determination of sediment nutrients in the cage fish culture area (before breeding) of the southern Caspian Sea (Mazandaran coast-Kelarabad)

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    This study was conducted to determine phosphorous and nitrogen species at the surface sediment in the southern Caspian Sea (Mazandaran Coast, Kelarabad). Surface sediments samples were collected at three stations from autumn of 2011 to winter of 2012. All samples were prepared by digesting and extracting processes and then phosphorous and nitrogen species concentrations determined using spectroscopy instrument. Results of this study showed that annual mean of Loosely-P, Fe-P, Al-P, Bioava.-P, Ca-P, TIP, Rese.-P and TP was obtained as 5.06±0.33, 55.11±2.52, 42.38±3.74, 102.52±5.68, 172.91±7.12, 275±9.12, 333.30±28.52 and 608±52 µg/g.dw, respectively. The results also showed that inorganic phophorous was less than organic phophorous during different seasons, however, mean percentage of residue-P containing organic compounds and non-degradable compounds was more than 50 percent. Percentage of Ca-P was higher than 60, whereas Bioava.-P was less than 40 percent. In addition, Fe-P and Loosely-P attained the maximum and minimum values, respectively, among the bioavailable phophorous. The order of different forms of phosphorous were recorded as Org-P>Ca-P>FeP>Al-P>Loosely-P. Annual mean of NH4/N, NO2/N, NO3/N, TIN, TON and TN were observed as 4.23±0.50, 0.06±0.01, 0.74±0.12, 5.02±0.53, 2.48±0.63 and 7.53±0.51 µg/g.dw, respectively. Annual percentage of TIN was two folds than TON and concentration of NH4/N was also four times than NO3/N. As a conclusion, the results revealed that main causes of Bioava.-P adsorption and desorption were temperature, Eh and pH. Also, the form of NH4+/N was of a high percentage because of anaerobic condition in the sediments. According to the high ratios of nitrogen/phosphorous of sediments to nitrogen and phosphorous of bottom water, it finds that released of those from the sediments to water will be happened with high rates. Therefore, it is expected that the establishment of fish farming cages should be carried out with more precautionary approaches which not leads to increased algae bloom
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