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Showing 9 results for Wetland
Survey of Heavy Metals (Cd, Pb, Hg, Zn and Cu) Contamination in Sediment of Three Sites Anzali Wetland
M Khosravi, N Bahramifar, M Ghasempour,
Volume 4, Issue 2 (9-2011)
Abstract

Background and Objectives:Anzali Wetland is one of the most important aquatic ecosystems of Iran which is located in south-west of the Caspian sea. This Wetland provides a suitable and non-market price habitat for valuable fish and aquatic animals which have an important role in the life cycle of this ecosystem. This study reports the results of some heavy metals contamination monitoring in superficial water of the Anzali Wetland, Iran.
Materials and Methods: The samples were collected from three sites (east, center and west) of Anzali Wetland, in each site three stations existed and each sample replicated three times.
Results: The results showed high heavy metal levels in eastern site of wetland, where there were high levels of contamination. The mean of heavy metals concentration in sediment from Anzali Wetland were in order as Cd 157.023, Pb 3.646 and Hg 300.692 ng /g dried weight, Zn 186.953 and Cu 44.452 mg /g dried weight in eastern site. The concentration levels of heavy metals in three sites were in order as follows: Zn > Cu > Hg > Cd > Pb.
Conclusion: Concentrations of heavy metals in eastern zone reflected metal loadings from anthropogenic sources located at and in the vicinity of the sampling sites.


Ecological Risk Assessment of Polycyclic Aromatic Componds in the Surface Sediments of Anzali Wetland in 2010
Rokhsareh Azimi Yancheshmeh, Ali Reza Riyahi Bakhtiari, Samar Mortazavi,
Volume 7, Issue 2 (10-2014)
Abstract

Background & Objectives: In recent years, enterance of oil contaminants especially polycyclic aromatic hydrocarbons (PAHs) to Anzali Wetland, has seriously threatened organisms life. Therefore, the current study was conducted to determine and compare concentration of PAH compounds with multiple sediment quality assessment indice to evaluate the ecological toxicity of surface sediments of Anzali Wetland and present appropriate management strategy. Materials & Methods: We randomly collected 22 surface sediment samples each sample was dried and extracted based on the soxhlet method. Then during two-step of column chromatography the PAH compounds were separated and analyzed by gas chromatography equipped with a mass spectrometry detector (GC-MS). Results: Total concentrations of these compounds ranged from 212 to 2674 ng g-1 d.w. with the mean of 907 ng g-1 d.w. The highest concentrations of PAHs was reported from stations (3-1 and 4-1) located in the vicinity of urban areas with shipping activities. In comparison with sediment quality guidelines (SQGs) used in this study, the concentrations of most PAH compounds in the majority of stations situated in low range values of adverse biological effects. Only in a few stations (3-1, 3-2 and 5-3), the concentrations of some of PAH compounds exceeded the low range of adverse biological effects. Conclusion: In comparison with sediment quality guidelines (SQGs) used in this study, the concentrations of most PAH compounds in Anzali Wetland rarely lead to adverse biological effects. However, concentrations of some of these compounds can cause acute toxic effects. Therefore, further studies including toxicity and bioaccumulation tests and survey of benthic community composition, especially in areas exceeded SQGs are essential for proper management.


Concentration of total and organic mercury and antagonistic relationship between selenium and organic mercury in the sediments of the international Anzali wetland
S Alidoust, N Bahramifar, A Esmaeli Sari,
Volume 10, Issue 1 (6-2017)
Abstract

Background and Objective: Mercury (Hg) is considered as a global pollutant that is widely dispersed in the environment. Monitoring of total mercury (THg) concentration in the sediments without determination of organic mercury (OHg) and selenium (Se) is an unreliable approach to evaluate the precise toxicological effects of Hg. In the present study, concentrations of THg, OHg and Se in the surface sediments of the eastern and western parts of Anzali wetland were investigated. In addition, the correlation of THg and OHg with Se and total organic carbon were analyzed.

Materials and Methods: Forty surface sediment samples were collected from the eastern and western parts of the wetland. Analysis of total and organic mercury in the sediment samples were done with Advanced Mercury Analyzer and the concentration of selenium was measured using inductively coupled plasma atomic emission spectroscopy (ICP-OES).

Results: The average concentrations of THg in the East and West wetlands were 109.53 and 68.39 ng/g dw, respectively. The average concentration of THg in the sediments of the eastern part of Anzali Wetland was significantly higher than that of the western part (P<0.001). The mean concentrations of OHg in East and West wetland were about 34.91 and 28.84 ng/g dw, respectively. There was  no significant relationship. The ratio of OHg to THg showed significant differences in the two studied areas. The average concentrations of Se in East and West wetlands were 156.25 and 163.75 ng/g dw, respectively. There was a significant negative correlation between the concentration of selenium and organic mercury in sediments of  the western part of  wetland (P<0.05).

Conclusion: The THg concentration in the sediments of Anzali wetland was lower in comparison to other studied regions of the world. However, the percentage of OHg in the Eastern and Western part of wetland was high. Therefore, bioavailability and toxicity of Hg would be high in the sediments and aquatic environment. In this study, in spite of high molar ratio of Se to THg, there was relatively high content of OHg. We recommend to measure the various Se-species that are effectively bound to inorganic Hg and to determine the amount of Se and Hg in aquatic organisms.


Evaluation of water quality of the Anzali international wetland using TOPSIS method
M Fallah, Ar Pirali Zefrehei, Saa Hedayati,
Volume 11, Issue 2 (9-2018)
Abstract
Background and Objective: Due to the vulnerability of water resources, quality control of surface water is one of the key issues in environmental conservation programs. In recent years, Anzali wetland has been exposed to numerous threats, including environmental pollutants. TOPSIS is an efficient and reliable way to assess the quality of water resources.
Materials and Methods: In order to evaluate water quality condition, Biochemical Oxygen Demand (BOD), Dissolved Oxygen (DO), temperature, pH, turbidity, Total Suspended Solid (TSS), phosphate (PO4-), nitrate (NO3-) and Fecal Coliforms (FC) were measured seasonally from 10 sites of Anzali International Wetland in 2014 and the water quality condition was estimated using TOPSIS method.
Results: The highest BOD5, phosphate, temperature and fecal coliform were measured at station 8. Comparison of TOPSIS values in different sampling stations showed the minimum (0.339) and maximum values (0.689) at the stations 5 and 8, respectively. According to the result, the station 5 (Sorkhankal) had the best water quality condition and station 8 (Pirbazar) had the lowest one. Also, seasonal results of TOPSIS values showed that the maximum value was at spring (0.742).
Conclusion: Discharge of effluents from land uses, agricultural and industrial activities located along the stream, could be considered as important reasons for decreasing water quality. Our results showed that TOPSIS method was clearly able to demonstrate the qualitative changes of water resources, indicating a moderate water quality for Anzali international wetland.

Ecological quality assessment of Anzali wetland for heavy metals using heavy metals pollution index (HPI)
F Jaffari, N Hassanzadeh,
Volume 12, Issue 2 (9-2019)
Abstract 
Background and Objective: Research has shown that assessing the toxicity and ecological risk of various types of pollutants, including heavy metals, using specific indicators, is indispensable in the ecological risk assessment of the ecosystem. Accordingly, the aim of this study was the assessment of the ecological effect of heavy metals presence (Pb, Zn, Cu, Cd and, As) in Anzali wetland using Heavy Metals Pollution Index (HPI).
Materials and Methods: 43 water samples were collected from the eastern, western and central parts of Anzali wetland. The samples were transferred to the laboratory, and the preparation steps were carried out using the ASTM method. Concentration of the elements was determined by Inductively Coupled Plasma -Atomic Emission Spectroscopy (ICP-AES). According to the concentration of heavy metals in the water samples, the index (HPI) was calculated. The results of the HPI index were classified into three classes: low risk (<15), moderate (15-30), and high risk (> 30).
Results: The numerical value of the HPI index was 3.59-23.3 with an average of 27.97, indicating the average level of heavy metals pollution in Anzali wetland. Indicator (HPI) in the eastern part of Anzali wetland and ​​the Pirbazar area showed a severe contamination and ecological hazard of the heavy metals and in the Abkenar region showed an acceptable ecological status.
Conclusion: Although the average of HPI in the whole Anzali wetland was modest, but at some stations, especially in the east of the wetland, the HPI indicates the occurrence of ecological hazards in the wetland in the event of uncontrolled entry of pollutants in future. Therefore, monitoring the sources of these pollutants entering to the wetland and controlling the ecological risks is necessary.
 
Evaluation of the performance of conventional and baffled horizontal subsurface constructed wetland in the removal of Reactive Red 198
Hadi Entezari Zarch, Mohamad Javad Zoqi, Mohamad Reza Doosti, Somayeh Rahmani,
Volume 13, Issue 1 (4-2020)
Abstract

Background and Objective: Reactive Red 198 is a mono azo dye widely used in the textile industry of Iran. The toxicity of reactive dyes is higher than other dyes and causes disorders such as irritation, cancer and mutation in humans. The overall objective of this study was to determine the efficiency of a Constructed Wetland pilot system with conventional and baffled horizontal subsurface flow to remove Reactive Red 198.
Materials and Methods: In order to remove Reactive Red 198, two cells were constructed in parallel with 2 × 0.6 × 0.5 m. In the conventional and baffled cell, native straw of Phragmites australis was used. In the research process, COD concentration and reactive dye concentration were investigated. The effect of retention time and type of plant on the efficiency were also investigated.
Results: The results showed that the maximum removal efficiency of the Reactive Red dye 198 was obtained at 100 mg/L inlet pollutant concentration and 3.5 days retention time, which was related to the baffled cells. Also, the presence of the baffles in the constructed wetland system increased the removal efficiency. The presence of straw in both cells was directly affected the removal efficiency. The effect of the retention time in the conventional cell was more effective in removal efficiency than the baffled cell. The pollutant inlet concentration was also inversely correlated with the removal efficiency.
Conclusion: According to the results, it can be concluded that the baffled and conventional horizontal subsurface constructed wetland can be used for low concentrations and at low retention time as a well-functioning system in the removal of Reactive Red 198.


Investigating the efficiency of surface flow constructed wetlands by using Cyperus alternifolius plants for nitrate removal from water
Reza Nazarpoor, Masumeh Farasati, Abolhasan Fathaabadi, Mohamad Gholizadeh,
Volume 13, Issue 1 (4-2020)
Abstract
Background and Objective: Synthetic wetlands are engineering systems that use natural plants, soils and organisms to purify municipal polluted water and remove nitrate.
Materials and Methods: In this study, three systems were considerd as soil culture, three systems as plant cultivation on floating plates and three other systems without plant and porous bed as. The experiments were done three times within six months. The hydraulic retention times were 1, 3 and 5 days. The experimental design consisted of a factorial split-plot design. The analysis of variance showed that the efficiency of nitrate removal was affected by the type of constructed wetland, HRT, and temperature changes (p≤0.01).
Results: At the HRT of 1 day, the average efficiency of nitrate removal by the soil culture, plant cultivation on floating plates and control  were 14.34%, 12.09% and 10.51%, respectively. At the HRT of 3 days, the average efficiencies were 17.62%, 15.76% and 13.54%, respectively. At the HRT of 5 days, the efficiencies were increased and they were 17.75%, 17.66% and 16.08%, respectively.
Conclusion: The results showed that the soil culture were more efficinet in removing nitrate .Also, the Cyperus alternifolius plant has the potential of nitrate phytoremediation.

Feasibility of using agricultural effluents entering Khorramshahr (Naseri) wetland in haloculture projects from the viewpoint of contamination with pesticides
Fateme Rezaee, Meisam Rastegari Mehr, Ata Shakeri,
Volume 16, Issue 3 (12-2023)
Abstract
Background and Objective: Water resources deficiency has caused the use of effluents to be considered as a source for re-use in the form of haloculture projects. An attempt has been made to investigate the possibility of using effluent produced by sugarcane production companies in the implementation of haloculture projects, from the viewpoint of the most used pesticides.
Materials and Methods: Ten water, four sediment, two plant, and two fish samples were analyzed using gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC) to determine the concentration of pesticides. In order to assess the ecological risk, toxic unit (TU) and risk quotient (RQ) were calculated.
Results: Glyphosate and Ametryn in all liquid, solid, and biological samples had concentrations below the detection limit. 2.4.D, Metribuzin, and Atrazine had detectable concentrations in the samples. However, their concentrations are lower than the standard values. Metribuzin and Atrazine had high concentrations in the stems and leaves of reeds in the region, which may indicate the role of these plants in the remediation of water and sediment from these compounds.
Conclusion: Using effluent from Amirkabir and Mirzakouchak Khan agro-industrial complexes to implement the haloculture project does not pose a particular problem from the viewpoint of contamination with the studied pesticides. This is confirmed due to the small concentrations of the studied compounds in the liver and below the detection limit in the muscles. However, it is necessary to carry out more studies to evaluate the quality of effluent in terms of the other types of pollution.
 

Contamination levels and human health risk assessment of mercury in some fish species from the Anzali International Wetland, Iran
Hassan Malvandi,
Volume 17, Issue 2 (9-2024)
Abstract
Background and Objective: The presence of toxic mercury in fish has caused global concern, as one of the main ways of humans are exposed to it is through fish consumption. Therefore, the main goal on this research was to determine the concentration of mercury in fish and evaluate the health risk to consumers.
Materials and Methods: Samples of pike, common perch, European perch, common carp and goldfish were collected from Anzali wetland. Mercury concentration was measured using a graphite furnace atomic absorption spectrometer. Differences in mercury concentration among the species and the comparison of mercury concentration with the standards were analyzed using one-way analysis of variance and one sample t-test, respectively.
Results: The average concentrations of mercury for pike, common perch, European perch, common carp and goldfish were 59.59, 67.55, 30.45, 9.84, and 10.44 µg/kg ww, respectively. The results showed significant differences in mercury concentrations among different species. The concentrations of mercury in all samples were below the permissible limits of international standards (300 and 500 µg/kg dw), and the HQ index values were less than 1. Therefore, the results indicated no potential risk to consumer health. Additionally, the consumption of European perch, common carp and goldfish is considered safe for sensitive people (children and pregnant women).
Conclusion: In general, there was no potential concern regarding mercury exposure from consuming the studied fish species.
 

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