فهرست مطالب

Caspian Journal of Environmental Sciences - Volume:15 Issue: 4, Autumn 2017

Caspian Journal of Environmental Sciences
Volume:15 Issue: 4, Autumn 2017

  • تاریخ انتشار: 1396/10/15
  • تعداد عناوین: 8
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  • M. Mohammadi-Zadeh Khoshroo, M. Shamsaie Mehrjan, F. Samiee, M. Soltani, S.P. Hosseini Shekarabi Pages 299-308
    All organisms are probably exposed to different types of electromagnetic fields (EMFs). This study is an attempt to evaluate the effect of extremely low-frequency EMFs (50 Hz) on some growth parameters and survival rate of common carp fingerling. The fry (n = 120, averaged 16.76 ± 0.88 g in initial weight) was exposed to ELF-EMF at four intensities of 0.1, 0.5, 1 and 2 mT only once for 2 h and then reared for 60 days. The obtained results revealed that all growth indices were significantly (p
    Keywords: Electromagnetic fields, Cyprinus carpio, Growth, Survival
  • M. Oveysi, S.H. Jamili, M. Behdani, A. Mashinchian Moradi, E. Sharifpoor Pages 309-319
    Chemical contamination of aquatic environments to EDCs has become a major focus of environmental toxicology research. The exposure of fishes to estrogenic EDCs in aquatic environments is most frequently assessed by analyzing Vitellogenin (Vg) (the egg yolk precursor protein) expression. Therefore, characterization of Vg gene is of high priority for EDCs bio-monitoring. So, we prepared liver tissue samples of Caspian roach, Rutilus caspicus for RNA extraction. Following the cDNA synthesis, specifically - designed primers were employed to amplify the Vg gene and ultimately sequence it. The evolutionary analyses of the sequence were performed using MEGA7 software. The obtained results indicated that the designed primers successfully amplified the partial cDNA sequence. Our results indicated that this sequence most probably belongs to the Vg1 form of the gene. Moreover, it was demonstrated that Caspian roach and Petroleuciscus esfahani share a common ancestor. Noteworthy, the study of Vg gene would be helpful to understand the molecular mechanisms of development and would be used to establish a bio-monitoring tool for detection of exposure to different EDCs.
    Keywords: Vitellogenin gene, Caspian roach, Rutilus caspicus, EDCs, Endocrine disrupting compounds
  • M. Yazarloo, H.G. Kami, A. Bagherian Yazdi Pages 321-334
    The Caspian pond turtle, Mauremyscaspica, is a terrapin belonging to family Geoemydidae. Totally 130 specimens (67 males and 63 females) were collected manually and by net from different aquatic habitats in Golestan Province from 2016 through 2017. Morphometric characteristics such as length were measured using digital caliper and weight by electronic weighting scale. Skin of this turtle was dark olive green in color and had rows of longitudinal yellow stripes around the head and neck. Their carapace was relatively flat, the bridges between the dorsal and ventral shells were bony, and the ends of anal scutes were found to be pointed. Fingers and toes had swimming membranes. Sexes were identified using the location of vent on the tail. Sex ratios of males to females were nearly 1:1. The maximum straight carapace length (SCL2) was 80.66- 230.16 (156.72 ± 42.93) and 56.96 - 236.84 (147.02 ± 50.76) in males and females respectively. Ratios of SCL2 to maximum plastron length (PL2) were found to be 1.013 - 1.32 (1.15 ± 0.04) in males and 1.01 - 1.15 (1.08 ± 0.03) in females; ratios of SCL2 to straight carapace width (SCW) were 1.24 - 2.60 (1.40 ± 0.16) in males and 1.20 -1.47 (1.35 ± 0.07) in females; ratios of SCL2 to carapace height (CH) were 2.28 - 3.55 (2.79 ± 0.22) in males and 2.05 - 8.78 (2.87 ± 1.11) in females; ratios of SCL2 to tail length2 (TL2) were 2.33 - 7.59 (3.76 ± 0.91) in males and 2.34 - 4.78 (3.06 ± 0.62) in females. Ratios of straight width of femuro-anal suture (FASW) to anal seam length (AnSL) were 2.95 – 5.89 (3.78 ± 0.54) in males and 2.65 - 4.13 (3.23 ± 0.40) in females. The ratio of TL2 to TL1 and TL1 to RBrL are found to be the fast and simple grouping index to determine sex of the specimens.
    Keywords: Caspian pond turtle, Golestan Province, Morphometric, Sexual dimorphism
  • M. Kazemzadeh, A. Malekian Pages 335-343
    In this paper, we analyzed the streamflow droughts based on the Percent of Normal Index (PNI) and clustering approaches in the Kurdistan Province, Iran, over the 1981-2010. The Kolmogorov-Smirnov (K-S) test was considered for streamflow time series and the results of K-S test indicated that streamflow time series did follow the normal distribution at the 0.05 significance level. Generally, the results showed that mostly streamflow droughts have been commenced since 1997 and also in most of the stations the extreme streamflow droughts occurred in 1997-2001. Furthermore, the number of drought events in each station showed that the extreme streamflow drought status in the Shilan station was the highest number with value 12, while the Tunnel Chehelgazi showed the lowest extreme drought status with value 4. Meanwhile, we used clustering approaches in order to explore homogeneities area which suffered from streamflow droughts. We selected two different clusters. So that, 5 stations out of 6 stations were classified in cluster 1 having the same situation in most years. The Shilan station had the specific conditions compared with other stations and classified in cluster 2. As a result, the clustering analysis was able to explore homogenous areas suffered from the same streamflow droughts. Therefore, the results of this work showed that the study area suffered from streamflow drought events over the three last decades, especially in last 14 years which can lead to many impacts on environment and ecosystems.
    Keywords: Streamflow, Clustering, Droughts, Kurdistan Province
  • A. Zaribafan, M. Baharlouie Yancheshmeh, T. Fathi, R. Ahmadkhani, K. Haghbeen Pages 345-357
    Spectrophotometric examinations showed the presence of phenolic compounds in the organic residue collected from four groundwater resources located in vicinity of an oil refinery at the outskirt of Tehran. The average concentration of total phenolic compounds was about 0.38 mg.L-1 in these samples using Folin-Ciocalteu method. GC-Mass analysis disclosed that alkylphenols were the major phenolic contaminants in the samples. Evaluation of the Advanced Oxidation Processes (AOPs) efficacy for removal of alkylphenols from real water samples is a hot topic of recent Environmental Research due to the decomposition of these compounds in soil and by microorganisms which may results in the formation of structures more resistance against various types of oxidation. To explore the efficacy of AOPs for removal of alkylphenols from the examined groundwater resources, the optimal conditions for three important AOP including Fe2ﱽ軛 (Photo-Fenton), O3/UV and O3/UV/H2O2 were first sought using a recalcitrant lab sample containing different aromatic compounds with total concentration of 2 mg.L-1. Consequently, two methods of O3/UV (2 mg.L-1 O3, 15 min UVC), and O3/UV/H2O2 (2 mg.L-1 O3, 5000 mg.L-1 H2O2, 15 min UVC) were selected to be examined on the real samples. Although the selected methods were quantitatively effective on the lab sample, they resulted in average removal efficiencies of 79.71% and 84.16% on the real samples, respectively. With respect to the safety regulations, costs and easiness of implementation, the O3/UV method seems to be more promising for large-scale plans.
    Keywords: Alkylphenols, Underground water, Ozone, UV radiation, Hydrogen peroxide
  • H. Hamedani, A. Naqinezhad, F. Fadaie Pages 359-374
    Ramsar international wetlands of Alagol, Almagol and Ajigol with a surface of 3027 ha are located in the vast Turkmen-Sahra plains (Golestan prov.) in east of Caspian Sea and in the vicinity of the Iran-Turkmenistan political border. Flora, vegetation and habitat diversity of the wetlands were surveyed during growing seasons of 2014 and 2015. A total of 159 plant taxa belonging to 123 genera and 42 families were determined in the studied wetlands. Asteraceae, Amaranthaceae (including Chenopodiaceae) and Poaceae were the most species rich families and Suaeda, Salsola, Atriplex, Plantago and Tamarix were the most species rich genera. A floristic analysis indicated that therophytes and pluriregional elements predominated life form and chorological spectra, respectively. Studied sites were physiognomically classified into aquatic, emergent, and dry upland habitats which represent 6, 68 and 26 percent of all plant taxa, respectively. Halophytic species constitute a large part of flora, among them Puccinellia poecilantha recently recorded in the area is considered as a rare plant. The results may be applied in designing conservation areas and developing conservation strategies for this unique wetland ecosystem.
    Keywords: Flora, Golestan, Habitat diversity, Ramsar wetlands, Salt marsh
  • P. Attarod, S.M.M. Sadeghi, T.G. Pypker, V. Bayramzadeh Pages 375-386
    The Persian oak, Quercus brantii, trees in the Zagros region of Western Iran have been in decline since 2000. The decline is assumed to be highly connected with changes in meteorological parameters. Our objectives were to quantify the long-term trends in meteorological parameters and reference evapotranspiration (ET0) in the Zagros region and estimate ecohydrological parameters highly affected by climate variability and related to rainfall interception (I) process (i.e., canopy storage capacity (S), the ratio of mean evaporation rate from the wet canopy to the mean rainfall intensity (E/R), and the free throughfall coefficient (p)). Long-term (1961-2010) changes in air temperature (T), precipitation (P), and wind speed (WS) were obtained from six synoptic meteorological stations located in the region. Throughfall (TF) was measured using the sixteen rain gauges randomly located underneath the crown of the five individual trees. P was measured using rain gauges fixed in an open space nearby to the oak trees .I was computed as the difference between P and TF. From 2000 to 2010, meteorological parameters and ET0 changed slightly; T, WS, and ET0 increased (.6 ˚C, .4 m.s-1, .25 mm.day-1, respectively), while P decreased (-60 mm).When climate patterns between 1961-2010 were analyzed for 6 synoptic weather stations, P significantly decreased significantly at one station, whereas T significantly increased at two stations and significantly decreased at another. I was estimated to be 40% and 25% within in-leaf and leaf-less periods, respectively. During the in-leaf period, the mean values of S, E/R, and p were roughly estimated to be 1 mm, 0.22, and 0.23, respectively. Our results indicate that the Zagros region is getting warmer and oak trees will indisputably experience reduction in the available water because of increased evaporative loss.
    Keywords: Ecohydrological parameters, Evapotranspiration, Interception, Meteorological parameters, Oak trees decline
  • M. Tabatabaei, A. Salehpour Jam Pages 387-401
    Sediment rating curve (SRC) is a conventional and a common regression model in estimating suspended sediment load (SSL) of flow discharge. However, in most cases the data log-transformation in SRC models causing a bias which underestimates SSL prediction. In this study, using the daily stream flow and suspended sediment load data from Shalman hydrometric station on Shalmanroud River, Guilan Province, Iran, SRC equation was derived, and then, using evolutionary algorithms (genetic algorithm and particle swarm optimization algorithm) it was calibrated again. Worth mentioning, before model calibration, to increase the generalization power of the models, using self-organizing map (an unsupervised artificial neural network for data clustering), the data were clustered and then by data sampling, they were classified into two homogeneous groups (calibration and test data set). The results showed that evolutionary algorithms are appropriate methods for optimizing coefficients of SRC model and their results are much more favorable than those of the conventional SRC models or SRC models corrected by correction factors. So that, the sediment rating curve models calibrated with evolutionary algorithms, by reducing the RMSE of the test data set of 5754.02 ton/day (in the initial SRC model) to 1681.21 ton.day-1 (in the calibrated models by evolutionary algorithms) increased the accuracy of suspended sediment load estimation at a rate of 4072.81 ton.day-1. In total, using evolutionary algorithms in calibrating SRC models prevents data log-transformation and use of correction factors along with increasing in the accuracy of molding results.
    Keywords: Clustering, Genetic, PSO Algorithms, Sediment Rating Curve, Self, Organizing Map, Suspended Sediment Load