4 resultados para Pointers of fecal pollution

em Aquatic Commons


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The general purpose of this study is to investigate the degree of heavy metal accumulation in hard and soft tissue of sea urchin, and determining these tissues as the most suitable bioindicator for lead and cadmium in the environment of the sampling stations. The way of doing this assessment was MOOPAM. Samples were prepared and classified according to sea urchin organ (soft tissue, hard tissue, Tube feet, Test, Lantern Structure and spines) and then lead and cadmium were measured in them. Result of this study shows that hard tissue is a better index of lead and cadmium than soft tissue. The result of bioaccumulation of lead in the related tissue was found to be in the following order: Soft tissue=21, hard tissue=28.1, Test=20.8, Lantern Structure=20.5 and spines=23.9. The result of bioaccumulation of cadmium in the related tissue was found to be in the following order: Soft tissue=9. 7, hard tissue=5.01, Test=4.2, Lantern Structure=4.06 and spines=5.53.

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There are various tools for monitoring the concentration of pollutants on aquatic ecosystems. Today these studies are based on biological monitoring and biomarkers. The aim of this study was to measure the concentration of the acetylcholinesterase (AChE), glutathione S-transferase and catalase as biomarkers of heavy metal contamination in pearl oyster Pinctada radiata and their mechanism in aquatic ecosystems. Heavy metals lead, cadmium and nickel were measured in soft tissue and studied stations in four seasons. Samples were collected seasonally in Lavan stations, Hendurabi and Nakhilo (in the northern Persian Gulf) from spring 2013 to winter of that year by scuba diving. Pearl oysters are divided according to their shells size; shells separated from soft tissues and were transferred to the laboratory for analysis of heavy metals and enzymes. Moopam standard method for were used for measuring the concentration of heavy metals and for analyzing tissue concentrations of glutathione S-transferase in Clam the method recommended by Habig et al in 1974 were used. For measuring acetylcholinesterase Ellman method were used. Catalase contamination in pearl oyster in the supernatant obtained from the study based on the method homogeate soft tissue of mussels (Abei, 1974) was evaluated. The results showed that the concentration of lead has significant difference in sediments station, the concentration of lead in Lavan is significantly higher than the other two stations, This could be due to the movement of tanker, boats and floating refueling and with a considerable amount of wastewater containing oil and Petroleum into the water, and also due to precipitation and industrial discharges the lead in the region is increasing, land-disposed sewage sludge, has large concentrations of lead. Compare the results of this study with standards related and other similar studies at the regional and international level showed that pollutant concentration of heavy metals in all cases significantly less than all the standards and guide values associated. And also compared to other world research results have been far less than others, Being Less of the conclusion given in this research according that nickel is one of the indicators of oil pollution in the study area and emissions have been relatively low of oil. The concentration of acetylcholinesterase at several stations, in large and small sizes and in the seasons had no significant difference. Variations of catalase, and glutathione S-transferase were almost similar to each other and parameters, station and seasons were significantly different in the concentrations of these enzymes. The effects and interaction between various parameters indicate that following parameters has impact on the concentration of catalase and glutathione S-transferase. Stations; Seasonal changes in antioxidant enzymes related to (assuming a constant in salinity and oxygen) to age, reproductive cycle, availability of food and water temperature. With increasing temperature at warm season, antioxidant enzymes were increase, with increasing temperature and abundance of food in the environment the amount of antioxidant enzymes may increase. The presence of the enzyme concentration may indicate that the higher levels of the enzyme to eliminate ROS activities to be any healthier situation. At the time of gonads maturation and spawning season catalase activity increases. This study also indicates that catalase was significantly higher in the warm season. Due to low pollutants of heavy metals in the study area, a lower level of contaminants were observed in shellfish tissue incidents of international standards and strong correlation between the amount of heavy metal contamination in pearl oyster tissue and enzymes was not observed. Therefore, we can say that the pearl oyster remains in a healthy condition and the amount of enzyme is normal.

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Nowadays, Caspian Sea is in focus of more attentions than past because of its individualistic as the biggest lake in the world and the existing of very large oil and gas resources within it. Very large scale of oil pollution caused by development of oil exploration and excavation activities not only make problem for coastal facilities but also make severe damage on environment. In the first stage of this research, the location and quality of oil resources in offshore and onshore have been determined and then affected depletion factors on oil spill such as evaporation, emulsification, dissolution, sedimentation and so on have been studied. In second stage, sea hydrodynamics model is offered and tested by determination of governing hydrodynamic equations on sea currents and on pollution transportation in sea surface and by finding out main parameters in these equations such as Coriolis, bottom friction, wind and etc. this model has been calculated by using cell vertex finite volume method in an unstructured mesh domain. According to checked model; sea currents of Caspian Sea in different seasons of the year have been determined and in final stage different scenarios of oil spill movement in Caspian sea on various conditions have been investigated by modeling of three dimensional oil spill movement on surface (affected by sea currents) and on depth (affected by buoyancy, drag and gravity forces) by applying main above mentioned depletion factors.

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Making use of sea, as a place for dumping of wastes and other materials from human activities wasn’t forbidden before creation of the convention on the prevention of marine pollution by dumping of wastes and other matters (London Convention). Therefore, industrial countries, without any specific consideration, were dumping their wastes into the world’s seas. Many years and before the beginning of rapid development of industry, the great self- purification of seas were preventing some of discharging problems. But gradually, the increase of industrial development activities, exceeded the production of wastes and other matters, and this led to the misuse of world’s seas and oceans as a dump site. One of the most important consequences of 1972 Stockholm World Conference was to focusing world attention on threats have jeopardized marine environment balance. World countries` leaders committed in Stockholm to begin protecting the environment. Finally, this movement at marine environment section led to the creation of London Convention in the same year. London Convention was concluded for cooperating between countries at December 29, 1972 to promote effective control of all marine environment polluting resources and to prevent marine pollution by dumping wastes and other matters. Then it was opened for signature to other countries. At last, after 15 states signature, this convention was entered in to force at August 30.1975. Ratification and execution of London Convention resulted in coordinated performance of countries in marine waste management. Common actions with supports and cooperation of different international, regional, governmental and non-governmental organizations and agencies prevent marine pollution by dumping of wastes and other matters. Due to the importance of wastes in our marine and coastal areas, investigation of the performance of London Convention can identify the lack of regulations and lack of regulation supports about marine pollution prevention by dumping of wastes and other matters in Iran. Considering this issue, proper protection of seas will be achieved. London Convention has been studied here to achieve intended purposes. In first chapter, generalities about marine environment, including the importance and necessity of marine environment protection, with the focus on some internal and international resources of environmental law accompanying with marine pollution and its recourses, and finally, due to the study theme, dumping of wastes and other matters at seas with its impacts have been investigated .In the section of international measures, a brief history of marine pollution and marine environment international law with international law framework, exclusively for controlling of wastes and other material discharge at seas and oceans has been reviewed. In second chapter, obligations, amendments, and annexes of London Convention have been investigated and classified. The obligations have been categorized in to legal obligations and technical and organizational obligations. In former section, subject ,purpose, territory, exceptions, rights and duties of parties, convention amendments,… and in latter, special requirements for wastes assessment, determination of pollutants` permissible limit, site selection and type of discharge selection, design principles for marine environment quality monitoring program, and discharge license issuance mechanism have been studied. In third chapter, due to the examination of convention performance in Iran, the internal law system for marine environment conservation and its pollution has been mentioned in detail. Considering this, two issues have been compared .firstly, convention obligations with regional treaties that Iran as a party to them and secondly, Iranian internal law there of .Finally, common and different aspects of these issues have been determined. At last, recommendations and strategies for convention enforcement and conformity of its obligations with internal regulations have been presented. Furthermore, translation of convention English text has been reviewed and its protocol has been translated.