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Wetlands, as temporary or permanent water reservoirs, provide various benefits for the ecosystem, such as water supply, waste water treatment, and dust control. By the end of 2023, the Iranian government and the Ramsar Convention have registered 25 international and 226 national wetlands. West Azerbaijan and Mazandaran provinces have more wetland ecosystems than any other provinces. Semnan, Yazd, and Zanjan provinces have no wetlands. According to the Ramsar Convention of 1971, Iran has 32 aquatic ecosystems that have the potential to become wetland. In addition, according to the available data and the WHO standard, eight wetlands have the highest probability of producing dust and should be given more attention and care. We recommend the wetland management plan, which ensures their water requirements, protects them from degradation and pollution, and promotes their ecological restoration. Satellite image analysis can help explore how climate change affects dust intensity, considering the role of wetlands in dust control. [ABSTRACT FROM AUTHOR]

Background: The present study aims to assess the amounts of Zn, Cu, Cd, Pb, Ni, Co, Mn, and Fe by analyzing the particle composition of the surficial sediments in Ghezel Ozan River located in Zanjan, Iran. Methods: 18 sediment samples were collected from Ghezel Ozan River. After Aqua Regia Digestion, the studied heavy metals in sediment samples were determined by flame atomic absorption spectrophotometry. Several pollution indices, such as Enrichment Factor (EF), Geo-accumulation Index (Igeo), Pollution Factor (Cd), and Pollution Load Index (PLI), were calculated. Results: Observed average values (in unit mg kg-1) were in the range of Zn: 480.0-34294.0, Cu: 7.8-32.00, Cd: not detected -100.0, Pb: 22.0-256.0, Ni: 2.50-60.00, Co: 7.60-34.0, Mn: 144.0-31600.0 and Fe: 9320.0-62300.0. The Igeo index confirmed that the average values of Zn, Pb, and Cd are in the heavily contaminated levels. The mean EF index suggested minimal enrichment for Cu, Ni, Mn, and Co, whereas Zn, Cd, and Pb indicated severe enrichment. Conclusion: The average Cd, RI, and PLI indices for all investigated heavy metals confirmed a considerable contamination level. [ABSTRACT FROM AUTHOR]

Backgroчnd: Aras River is the main soчrce of drinking water sчpply in northwestern provinces of Iran. The present stчdy aimed to determine the concentration of heavy metals in the river on the border between Iran and Armenia. Methods: Three samples were taken from the Aras river water, the river bottom sediments and the root of Phragmites aчstralis. In water sampling, the concentration of Hg, Mo, Cч, C o, B, Cd, Ni, Zn, Pb, Al, Mn, Cr and Fe was noticed while in sediment sampling, to measчre the concentration of Cч and Mo. In samples taken from the plant root, the concentration of Cч was only analyzed. The water sampling was performed at 11 stations along the river coчrse dчring foчr seasons fall, winter, spring and sчmmer 2011. Resчlts: The highest and lowest concentrations respectively belonged to Al (2600 ppb) and Cd (0.4 ppb). Parameters inclчding B, Cч, Mo and Al were all higher than the standard limits. The resчlts obtained from sediment and root sampling indicated that the concentration of Cч exceeds the standard. Conclчsion: Poor qчality of Aras River reveals to the necessity of implementing mitigation measчres to improve the water qчality of the river. [ABSTRACT FROM AUTHOR]

The level of mercury, iron, copper, and zinc was measured in 18 Great cormorants (Phalacrocorax carbo) collected from Anzali and Gomishan wetlands in the south of the Caspian Sea. The mean level of metals in dried tissues of the muscle, liver, and kidney was 2.26, 5.71, 3.79—Hg; 943.54, 379.97, 348.05—Fe; 42.64, 14.78, 60.79—Cu, and 71.97, 134.63, 77.82—Zn, respectively (mg/kg). There was no significant different between genders in terms of accumulation of metals, except for copper in the kidney. The results of Pearson correlation showed a positive and strong relationship between the fat in the liver and mercury (r = 0.95, R2 = 0.90). Also, there was a significant difference between the values of all metals with the allowable limits presented in EPA, WHO, and CCME, where all of values were above standard levels. Thus, as the muscles of the bird are sometimes eaten by humans, this result is a serious warning. Nevertheless, the relatively high levels of heavy metals accumulated in different tissues of Great cormorant at that time are a result of their high weight and nourishment they have at the terminal days of their migration due to lack of natural physical activity. Regarding to the importance of heavy metals in birds, we suggest the same study to be conducted on the species in other seasons and wetlands. [ABSTRACT FROM AUTHOR]