Study of the development and evolution of seasonal thermocline and turbulent processes in the northern parts of Persian Gulf using numerical modeling

The Persian Gulf (PG) is a semi-enclosed shallow sea which is connected to open ocean through the Strait of Hormuz. Thermocline as a suddenly decrease of temperature in subsurface layer in water column leading to stratification happens in the PG seasonally. The forcing comprise tide, river inflow, solar radiation, evaporation, northwesterly wind and water exchange with the Oman Sea that influence on this process. In this research, analysis of the field data and a numerical (Princeton Ocean Model, POM) study on the summer thermocline development in the PG are presented. The Mt. Mitchell cruise 1992 salinity and temperature observations show that the thermocline is effectively removed due to strong wind mixing and lower solar radiation in winter but is gradually formed and developed during spring and summer; in fact as a result of an increase in vertical convection through the water in winter, vertical gradient of temperature is decreased and thermocline is effectively removed. Thermocline development that evolves from east to west is studied using numerical simulation and some existing observations. Results show that as the northwesterly wind in winter, at summer transition period, weakens the fresher inflow from Oman Sea, solar radiation increases in this time interval; such these factors have been caused the thermocline to be formed and developed from winter to summer even over the northwestern part of the PG. The model results show that for the more realistic monthly averaged wind experiments the thermocline develops as is indicated by summer observations. The formation of thermocline also seems to decrease the dissolved oxygen in water column due to lack of mixing as a result of induced stratification. Over most of PG the temperature difference between surface and subsurface increases exponentially from March until May. Similar variations for salinity differences are also predicted, although with smaller values than observed. Indeed thermocline development happens more rapidly in the Persian Gulf from spring to summer. Vertical difference of temperature increases to 9 centigrade degrees in some parts of the case study zone from surface to bottom in summer. Correlation coefficients of temperature and salinity between the model results and measurements have been obtained 0.85 and 0.8 respectively. The rate of thermcline development was found to be between 0.1 to 0.2 meter per day in the Persian Gulf during the 6 months from winter to early summer. Also it is resulted from the used model that turbulence kinetic energy increases in the northwestern part of the PG from winter to early summer that could be due to increase in internal waves activities and stability intensified through water column during this time.

Seasonal variation of acetylcholinesterase, catalase, glutathione s transferase in different size of Pinctada radiata and metal pollution (Pb, Cd, Ni) in Persian Gulf

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.

A review on systematic and taxonomic of the Persian Gulf fish species, based on geographical distribution pattern and habitat diversity, using by GIS

During the period from 2011 - 2015 with the aim of this study was to systematically review and in particular the revised classification of the Persian Gulf (and the Strait of Hormuz) and to obtain new information about the final confirmed list of fish species of Iranian waters of the Persian Gulf (and Hormuz Strait), samples of museums, surveys and sampling, and comparative study of all available sources and documentation was done. Classification systematic of sharks and batoids and bony fishes. Based on the results, the final list of approved fish of the Persian Gulf (including the Strait of Hormuz and Gulf of Oman border region) are 907 species in 157 families, of which 93 species of fish with 28 cartilaginous families (including 18 families with 60 species and 10 families with 34 species of shark and batoids); and 129 families with 814 species of bony fishes are. The presence of 11 new family with only one representative species in the area include Veliferidae, Zeidae, Sebastidae, Stomiidae, Dalatiidae, Zanclidae, Pempheridae, Lophiidae Kuhliidae, Etmoptridae and Chlorophthalmidae also recently introduced and approved. The two families based Creediidae Clinidae and their larvae samples for newly identified area. 62 families with mono-species and 25 families with more than 10 species are present including Gobiidae (53), Carangide (48), Labride (41), Blenniidae (34), Apogonidae (32) and Lutjanidae (31) of bony fishes, Carcharhinidae (26) of sharks and Dasyatidae (12) in terms of number of species of batoids most families to have their data partitioning. Also, 13 species as well as endemic species introduced the Persian Gulf and have been approved in terms of geographical expansion of the Persian Gulf are unique to the area.Two species of the family Poeciliidae and Cyprinodontidae have species of fresh water to the brackish coastal habitats have found a way;in addition to 11 types of families Carcharhinidae, Clupeidae, Chanidae, Gobidae, Mugilidae, Sparidae also as a species, with a focus on freshwater river basins in the south of the country have been found. In this study, it was found that out of 907 species have been reported from the study area, 294 species (32.4 %) to benthic habitats (Benthic habitats) and 613 species (67.6 %) in pelagic habitats (Pelagic habitats) belong. Coral reefs and rocky habitats in the range of benthic fish (129 species - 14.3 %) and reef associated fishes in the range of pelagic fishes (432 species – 47.8 %), the highest number and percentage of habitat diversity (Species habitats) have been allocated. As well as fish habitats with sea grass and algae beds in benthic habitat (17 species- 1.9 %) and pelagic - Oceanic (Open sea) in the whole pelagic fish (30 species – 3.3 %), the lowest number and percentage of habitat diversity into account. From the perspective of animal geography (Zoogeography) and habitat overlaps and similarities (Habitat overlapping) fish fauna of the Persian Gulf compared with other similar seas (tropical and subtropical, and warm temperate) in the Indian Ocean area - calm on the surface, based on the presence of certain species that the fish fauna of the Persian Gulf to the Red Sea and the Bay of Bengal (East Arabian Sea) compared to other regions in the Indian Ocean (Pacific) is closer (about 50%), and the Mediterranean (East area) and The Hawaiian Islands have the lowest overlap and similarity of habitat and species (about 10%).

Study of salinity gradients in the Persian Gulf and an experimental model for electric energy extraction from them using nano-membranes

Salinity gradient power (SGP) is the energy that can be obtained from the mixing entropy of two solutions with a different salt concentration. River estuary, as a place for mixing salt water and fresh water, has a huge potential of this renewable energy. In this study, this potential in the estuaries of rivers leading to the Persian Gulf and the factors affecting it are analysis and assessment. Since most of the full water rivers are in the Asia, this continent with the potential power of 338GW is a second major source of energy from the salinity gradient power in the world (Wetsus institute, 2009). Persian Gulf, with the proper salinity gradient in its river estuaries, has Particular importance for extraction of this energy. Considering the total river flow into the Persian Gulf, which is approximately equal to 3486 m3/s, the amount of theoretical extractable power from salinity gradient in this region is 5.2GW. Iran, with its numerous rivers along the coast of the Persian Gulf, has a great share of this energy source. For example, with study calculations done on data from three hydrometery stations located on the Arvand River, Khorramshahr Station with releasing 1.91M/ energy which is obtained by combining 1.26m3 river water with 0.74 m3 sea water, is devoted to itself extracting the maximum amount of extractable energy. Considering the average of annual discharge of Arvand River in Khorramshahr hydrometery station, the amount of theoretical extractable power is 955 MW. Another part of parameters that are studied in this research, are the intrusion length of salt water and its flushing time in the estuary that have a significant influence on the salinity gradient power. According to the calculation done in conditions HWS and the average discharge of rivers, the maximum of salinity intrusion length in to the estuary of the river by 41km is related to Arvand River and the lowest with 8km is for Helle River. Also the highest rate of salt water flushing time in the estuary with 9.8 days is related to the Arvand River and the lowest with 3.3 days is for Helle River. Influence of these two parameters on reduces the amount of extractable energy from salinity gradient power as well as can be seen in the estuaries of the rivers studied. For example, at the estuary of the Arvand River in the interval 8.9 days, salinity gradient power decreases 9.2%. But another part of this research focuses on the design of a suitable system for extracting electrical energy from the salinity gradient. So far, five methods have been proposed to convert this energy to electricity that among them, reverse electro-dialysis (RED) method and pressure-retarded osmosis (PRO) method have special importance in practical terms. In theory both techniques generate the same amount of energy from given volumes of sea and river water with specified salinity; in practice the RED technique seems to be more attractive for power generation using sea water and river water. Because it is less necessity of salinity gradient to PRO method. In addition to this, in RED method, it does not need to use turbine to change energy and the electricity generation is started when two solutions are mixed. In this research, the power density and the efficiency of generated energy was assessment by designing a physical method. The physical designed model is an unicellular reverse electro-dialysis battery with nano heterogenic membrane has 20cmx20cm dimension, which produced power density 0.58 W/m2 by using river water (1 g NaCl/lit) and sea water (30 g NaCl/lit) in laboratorial condition. This value was obtained because of nano method used on the membrane of this system and suitable design of the cell which led to increase the yield of the system efficiency 11% more than non nano ones.

Investigation on possibility of survival and growth enhancing by selected seaweeds from Persian Gulf in post larvae shrimp Litopenaeus vannamei

The use of antibiotics in aquaculture has been limited. Scientifics seeking for natural substitutes to prevent of aquatic animals diseases. Considering seaweeds are rich of nutritions and bioactive compounds, the purpose of this study is: investigation the potential and use possibility of native seaweeds from Persian Gulf in shrimp aquculture industry to improve growth, survival of postlarvae and to resistance against pathogens such as vibriosis. For this propose 7 macroalgae species from Bushehr province coast, inclouding: green algae (C. iyengarii), brown algae (S. angutifolium and S. ilicifolium) and red algae (L. snyderiae, K. alvarezii and G. corticata) were collected and identified. Then seaweed extracts abtained by Water, Ethanol, Methanol and Chloroform solvents by soaking method. In vitro antibacterial activity of extracts against Gr+ bacteria (S. aureus and B. subtilis) and Gr- bacteria (V. harveyi, V. alginolyticus and E. coli) was conducted by Agar diffusion, MIC and MBC methods. Antioxidant activity also by DPPH and EC50 methods was investigated. According to results of these two tests four seaweeds species (S. angutifolium, L. snyderiae, K. alvarezii and G. corticata) were selected for use in shrimp postlarvae (PL22) diets by Bio-Encapsulation (Artemia enrichment). Before of enrichment, toxicity effect of extracts to Artemia nauplii were evaluated by determination of LC50 24 h method. From results of this section Ethanol extracts were selected to bioencapsulation. After encapsulation shrimp postlarvae divided to 12 groups in triplicate, namely: C-, C+, S (200), S (400), S (600), L(200), L(400), L(600), G(300), G(600), K(300) and K(600). During 30 days of reared period C- and C+ use of basal diet and unenriched Artemia, but the other groups use of basal diet and enriched Artemia. Except C-, the shrimps in first day of culture put in 107 cfu/ml v. harveyi suspension for 30 minutes, and after water exchange 10 ml of this dose was added to reared aquaria. After 30 days survival percentage, obtained weight and SGR% were investigated. To evaluate vibrio loading, every 10 days 5 postlarvae were sampled randomly for vibrio count. Results showed that vibrio count in C- was less than the others and in C+ was more than the others. In treatments vibrio count in L(200) was the most and L(600) was the less. Survival rate in C- was the most and after that G(600) with 79.4±6.6% and then S(300) and K(600) were 73.3±7.3% and 70.6±6.6% respectively that were significantly compare the other (P < 0.01). Also the C+ was the less with 33.3±6.6% that difference was significant (P< 0.01). In this study growth parameters of all groups that fed by enriched Artemia were better than C+ (P<0.05). After cultre period 10 shrimp of every aquarium disinfected and reared for 10 days like before treatment. After 10 days the shrimps were challenged by 3×108 cfu/ml V. harveyi and mortality was recorded for 7 days. The all of animals in C- were survive but more than 90% of C+ were dead. And survival in all of treatments were better the C+ (P<0.05). The study showed the ethanol extracts of selected seaweed from Persian Gulf is a good source for growth, Survival and disease control in shrimp larviculture.

Investigation and prediction of sea level variations in the northern coasts of Persian Gulf using artificial neural network

Sea- level variations have a significant impact on coastal areas. Prediction of sea level variations expected from the pre most critical information needs associated with the sea environment. For this, various methods exist. In this study, on the northern coast of the Persian Gulf have been studied relation to the effectiveness of parameters such as pressure, temperature and wind speed on sea leve and associated with global parameters such as the North Atlantic Oscillation index and NAO index and present statistic models for prediction of sea level. In the next step by using artificial neural network predict sea level for first in this region. Then compared results of the models. Prediction using statistical models estimated in terms correlation coefficient R = 0.84 and root mean square error (RMS) 21.9 cm for the Bushehr station, and R = 0.85 and root mean square error (RMS) 48.4 cm for Rajai station, While neural network used to have 4 layers and each middle layer six neurons is best for prediction and produces the results reliably in terms of correlation coefficient with R = 0.90126 and the root mean square error (RMS) 13.7 cm for the Bushehr station, and R = 0.93916 and the root mean square error (RMS) 22.6 cm for Rajai station. Therefore, the proposed methodology could be successfully used in the study area.

Study the methods of connecting jacket to the seabed and choosing the best method for Persian Gulf according to soil characteristics

Offshore structures with numerous applications in different environments throughout the world and used at different depths. Due to the expansion of marine industries, including offshore oil industry in Iran , particularly in the Persian Gulf region, in order to more accurately model these structures and to prevent incidents such as the Overturning of the platform serious damage to the South Pars Phase ١٣ was platforms, the use New Technic is essential technologies. One of the methods that are used in the construction of offshore wind turbines, using a pre-pile. In this method, a template is constructed with the dimensions specified in the workshop. After making templates using special vessels for placement in the desired location on the sea bed is carried, then the template is placed on the sea bed, Then, using a hammer for Pile Driving Operation Started Vibration hammer and fit the template of 3 or 4 piles of crushed within this template on the seabed . The next step piling, templates have been removed from the site And Jacket placed on piles. The system was installed on the deck on piles and Consequently Deck Load pile inserted on .It should be noted that the design of these types of platforms, base diameter of the pile diameter independent of the choice as one of the major advantages of this system is. This thesis examines a Template Fixed Platform in the oil Soroush Using the Pre-Piling and the Common Piling systems in the Persian Gulf were studied and the effect of different design compared to the Pre-Piling Platforms Persian Gulf were evaluated. The results suggest that Pre-Piling system compared with conventional systems piling in the Persian Gulf, as a more appropriate model structure and behavior Top Model economic efficiency is selected. It should be noted that all calculations and analyzes were performed using Software Abaqus.

Diversity, abundance distribution and secondary production of intertidal and subtidal benthic macrofauna of Bushehr Province with emphasis on annelida groups

The present investigation was undertaken to establish a reference situation for future use, to identify temporal and spatial composition of macrofauna and estimate some ecological indices in the sub tidal waters along the Bushehr coastal waters in Persian Gulf. Six transects were selected including Genaveh, Farakeh, Shif, Bandargah, Rostami and Asalouyeh, at each transect 3 station were sampled in depths of zero, 5 and 10 metres. Sampling was seasonally carried out by a VAN VEEN grab 0.0225 m2, during summer 2008 until spring 2009. Samples were wet sieved immediately using 0.5 mm mesh size sieves and sediment retained in the sieve was preserved in 4% buffered formalin solution. Macrofauna specimen were separated from the sediments using decantation and elutriation methods, enumerated and identified up to the Genus level. Environmental factors such as temperature. pH, and salinity were recorded in field using sensitive probs and refractometer (for salinity) and also sediment samples were taken for TOM and grain size analysis in all the stations. 5611 specimens belonging to 66 genera were collected during the present study. Polychaetes were dominant both in terms of genus number (31) and relative abundance (74 % of total macrofaunal abundance). The other dominant groups were Artheropoda, (16.1%), Molusca (2.8%), Echinodermata (1.29%) and others including Nematoda, Nemertina, Echiura and Turbellaria (5.8%). Thirty one Genera belong of 27 families of polychaeta, one genus and family of Subphylum Chlicerata,19 genera belong to 14 families of Crustacea, 8 genera belong to 6 families of Molusca, were indentified in the studied region. 1 family (Polygordidae) and 3 genera (Flabeligera, Pilargis and Polygordius) of Polychaeta, 1 family (Nymphonidae) and genus (Nymphon) of Chelicerata, 1 Family (Nematoplanidae) and genus (Nematoplana) of Turbellaria, were identified for the first time in Persian Gulf area. The result indicated that macrofauna organism have strong relationship with the grain size characteristics of the sediments they inhabit. The most surface deposit feeder specimens such as Prionospio and Cossura were found in zero meters depth of Genaveh, Farakeh, Bandargah, Rostami and Asalouyeh stations with sandy substratum, however the most burrowing deposit feeder and scavenger specimens such as Capitella and Petaloproctus were collected in 5 and 10 meter depths of stations with silty–clay substratum. The annual mean abundance, Shanon- weiner diversity and evenness of macrofauna were estimated1152.73 N/ m² , 2.72 and 0.792 respectively .The annual average biomass and secondary production were computed 1.797 gDW m² and 3.594 gDW m² y-1 .The average of water temperature, salinity, pH and oxygen concentration were recorded between 16.37-36.05 °C, 38-42 g/l, 7.89-8.76 and 4.23-8.23 mg/l, respectively during this study in 6 studied region. Among of investigated stations Asalouyeh adjacent of effluent canal of Gas and petrochemical industry sewage and Farakeh regions adjacent the Helleh estuary had the lowets and the highest community indices. The average of diversity and density in 5 meters depth stations with moderate of sand, silt and clay were slightly more than 2 other depths stations, it seems that 5 meters stations are made a transition habitats between 2 sandy and clay habitats, that can be used by 2 groups of surface and borrowing deposit feeders. Based on the data provided in this survey, the temperature variation, sediment texture, TOM, type habitat and manmade factors of Gas and petrochemical industries have had the most effect on the macrofauna community structure in the studied region during sampling periods.

A survey on relation of morphological, molecular and phylogenetic structure of zoanthids of the islands located in the Hormoz Strait (Hormoz, Qeshm, Larak, Hengam)

The order Zoantharia (Zoanthids) is one of the most neglected orders of cnidarians in the Persian Gulf. The present study aims to investigate the biodiversity of this order with morphological and molecular examination in the Persian Gulf. For this purpose, 123 colonies of zoanthids with variety of shape and colors have been collected from intertidal and shallow water zone of four islands, i. e. Hengam, Qeshm, Larak and Hormoz. After sampling, morphological characteristics of each specimen were recorded based on in situ photographs. Then DNA was extracted using the cetyl trimethyl ammonium bromide (CTAB) method. Both mitochondrial 16S ribosomal DNA (mt 16S rDNA) and cytochrome oxidase subunit I (COI) gene fragments were amplified and sequenced. The results of preliminary morphological identification integrated with two mitochondrial markers sequencing demonstrated the presence of five different species in this region; Zoanthus sansibaricus, Palythoa mutuki, Palythoa cf. mutuki, Palythoa tuberculosa and Neozoanthus persicus?. Although at first sight, morphological properties were not successful to delineate zoanthid species, they become reliable criteria to identify and delineate species in field studies after molecular identification.

The study of maturational progress in the whitespotted rabbitfish (Siganus sutor) under different photoperiod and light intensity conditions

The rule of light on the timing of maturation and spawning in tropical and subtropical regions is not clear well, because the reproductive cycle in these systems is lunar synchronized. In this study, thus, the effects of different light regimes were investigated on maturational progress of whitespotted rabbitfish, Siganus sutor, the commercial species in Persian Gulf and Oman Sea. During prespawning season, 50 adult fish were randomly divided into ten 300-l tanks (n=5). The fish in control tank received indoor light condition and the fish in each other tanks were exposed to nine different combinations of photoperiod (8L: 16D, 12L: 12D, 16L: 8D) and light intensity (1000, 2000, 3000 lux). After 60 days, GSI and HSI values, serum levels of estradiol (E2), testosterone (T), 17-α hydroxyprogestrone (OHP), calcium (Ca2+) and gonad histology were evaluated for females and males. In females the GSI mean values of exposed fish increased in comparison with control except for fish were kept under 8L, 2000 lux (tank 8). These differences were significant only for fishes in tank 7 (8L, 3000 lux). In the cases of HSI, the results were converse, so that, the most of thanks showed significant decreasing than fishes reared under indoor condition. Morphology and histology study of Ovaries showed three developmental phases including 3, 4 and chiefly 5 that were parallel with GSI values. Fortheremore the serum levels of E2 was recorded between 0.54-15.8 ng/ml in different fish and their mean values were lower than control in all treatmants (P> 0.05). In males, the similar results were obtained. The GSI and HSI mean values in experimental regimes compared with control were upper and lower, respectively, except for fishes were reared in tank 1 (16L, 3000 lux). Testes histology of fishes were reared under different regimes showed signs of stage 5, since no blood vessels observed and thick milt exuded on slight pressure. The mean values of testosterone consentration in fishes were kept in tanks 1 and 6 (12L, 1000 lux) were higher and in other ones were lower than control group. It is also noted that the OHP and Ca2+ had diverse results including increasing and decreasing mean values than control. So, these factors contrary to E2 and T were not suitable to evaluation of maturity in both sexes. On the basis of ovarian structure in stage 5, oocyte development pattern in this species was group synchronous. So, increased mean of GSI versus decreased values of HSI, E2 and perhaps Ca2+ were the signs of improved maturation. But in males, reduced levels of T and similarity of testes morphology in all samples caused that GSI mean value was the only indicator for differentiating among treatments. These findings suggest that alternations were used in light regimes have been the reason of improved maturity in all treatments except fishes reared in tank 8. The ١٠٧ rule of light intensity on induction of maturity was cleared by comparision between fishes in tanks 4, 5, 6 and control group. Because day length was the same whereas fishes in tanks 4, 5 and 6 were exposed to increased light intensity compared with control. This fact verified by results was obtained from fishes in tanks 9 and especially 7, since photoperiod in this group was lower than control. So, higher intensity was considered as the reason of alternations. Contrasting with indoor condition, Induced maturity was also cleared for fishes were kept in tanks 1, 2 and 3, where both of light duration and intensity were increased. But, the rule of photoperiod was individually demonstrated when obtained results were compared with similar light intensities in other treatments. In conclusion, with comparison among different light regimes it is declared that siganids were kept under light condition of tank 2 including 16h light duration combined with 2000 lux intensity showed the best signs of sexual maturation in both sexes. On the basis of this study, setting up the spring light condition during prespawning season induces maturation in withspotted rabbitfish. This improvement not only by influence of photoperiod or light intensity, separately, but obtained through interaction between them. Thus, determination of threshold and resistance to light be recommended before exposure, although using proper regime during suitable time are necessary to achieve purposes considerably.

Biogeochemical study of poly aromatic hydrocarbons (PAHs) and its physiological affection response in mudskipper (Boleophthalmus dussumieri) at coast of Khuzestan

Study on the biomarkers types to assess health status of marine ecosystems in environmental biomonitoring has an important value. Accordingly, accumulation of polycyclic aromatic hydrocarbons(PAHs) in sediment, water and tissues (liver and gill) of mudskipper(i.e. Boleophthalmus dussumieri) and some physiological responses like lysosomal membrane change performed on haemocytes, stability of red blood cell membrane and the Glutathione-S Transferase (GST) activity in the liver were measured in mudskipper. Samples were obtained from five sites along north western coast of the Persian Gulf (Khuzestan coast). Red blood cell membrane changes after different concentration of PAHs at different time was also studied to evaluate impact of PAHs compound on cell membrane. PAHs concentration was measured by HPLC method. The activity of GST enzyme was analysed by spectrophotometric method. Lysosomal membrane change was measured by NRR time method and stability of red blood cell membrane was evaluated by EOF test. Total PAH concentrations in the coastal sea water, the sediments, the liver and the gill tissues ranged between 0.80-18.34 μg/l, 113.50-3384.34 ng g-1 (dry weight), 3.99-46.64 ng g-1 dw and 3.11-17.76 ng g-1 dw, respectively. Highest PAHs pollution was found at Jafari while the lowest was detected at Bahrakan sampling sites. The lowest enzymatic activity was identified at Bahrakan (7.19 ± 1.541 nmol/mg protein/min), while the highest was recorded at Jafari (46.96 ± 7.877 nmol/mg protein/min). Comparative analysis of GST activity in the liver of mudskippers showed significant difference (p < 0.05) between the locations of Jafari and Bahrakan, and with other sites. Moreover, no significant difference was detected between the locations of Arvand, Zangi and Samayeli (p < 0.05). The mean RT was below 90 minutes in all sampling sites. Values of mean RT of the dye ranged from 34 (for the blood samples of mudskipper collected from Jafari site) to 78 minutes (for the blood samples of mudskipper collected from Bahrakan site). Spatial evaluation revealed the longest RT in fish from Bahrakan as compared with those from other sites. Preliminary results showed a significant difference (p < 0.05) among sampling sites except between Arvand and Zangi (p > 0.05). Osmotic fragility curves indicated that erythrocytes collected from mudskippers at Jafari were the most 009 fragile followed by Zangi> Arvand> Samayeli> and Bahrakan. The mean erythrocyte fragility was significantly higher at Jafari site (p < 0.05) when compared to other sites. Significant differences were found between the various sites (p < 0.05).The result indicated no significant differences between the control and treatments of mudskipper RBC exposed to field concentrations of PAHs (P>0.05). The results further indicated significant differences (P<0.05) between the control and treatments of mudskipper RBC exposed to acute. Potency Divisor concentrations. It is clear from the present result that chronic. Potency Divisor concentrations protect red cells against osmotic hemolysis. This study, however, showed that PAH concentrations in this region are not higher than the available standards. The findings showed that Lysosomal membrane destabilization, liver GST activities and fragility of red cell membrane are highly sensitive in the mudskipper, B. dussumieri. Thus, mudskipper perceived to be good sentinel organisms for PAH pollution monitoring. Sediment PAH concentrations were strongly correlated with biomarkers, indicating that PAH type pollutants were biologically available to fish. One of the possible risk assessment implications of this study is that biomarkers can be applied not only to characterize biological effects of pollution exposures, but also to determine the bioavailability of pollution in aquatic systems. The results also indicated that PAHs compound possess anti haemolytic property.

New species of Berea (Copepoda, Chondracanthidae) parasitic on a flounder from Kuwait

Berea clava, new species, is described based on the specimens recovered from the gill filaments of a flounder, Pseudorhombus arsius (H.-B.), collected in Kuwait Bay of Arabian (Persian) Gulf. This is the second species of Berea.

Molecular identification of symbiotic dinoflagellates (Zooxanthellae) of dominant reef-building corals off Kish Island

Scleractinian coral species harbour communities of photosynthetic taxa of the genus Symbiodinium. As many as eight genetic clades (A, B, C, D, E, F, G and H) of Symbiodinium have been discovered using molecular biology. These clades may differ from each other in their physiology, and thus influence the ecological distribution and resilience of their host corals to environmental stresses. Corals of the Persian Gulf are normally subject to extreme environmental conditions including high salinity and seasonal variation in temperature. This study is the first to use molecular techniques to identify the Symbiodinium of the Iranian coral reefs to the level of phylogenetic clades. Samples of eight coral species were collected at two different depths from the eastern part of Kish Island in the northern Persian Gulf. Partial 28S nuclear ribosomal (nr) DNA of Symbiodinium (D1/D2 domains) were amplified by Polymerase Chain Reaction (PCR). PCR products were analyzed using Single Stranded Conformational Polymorphism (SSCP) and phylogenetic analyses of the LSU DNA sequences from a subset of the samples. The results showed that Symbiodinium populations were generally uniform among and within the populations of 8 coral species studied, and there are at least two clades of Symbiodinium from Kish Island. Clade D was detected from 8 of the coral species while clade C90 was found in 2 of species only (one species hosted two clades simultaneously). The dominance of clade D might be explained by high temperatures or the extreme temperature variation, typical of the Persian Gulf.

Copepods of the genus Hermilius (Caligidae) parasitic on marine catfish of Kuwait, with a key to the species of Hermilius

Three species of caligid copepods (Siphonostomatoida) belonging to genus Hermilius Heller, 1865 were recovered from the giant marine catfish, Arius thalassinus Ruppell, taken from the Persian Gulf. They are H. pyriventris Heller, 1865; H. longicaudus n. sp.; and H. longicornis Bassett-Smith, 1898. H helleri Pillai, 1963 is proposed to be relegated to the synonym of H pyriventris. A key to the eight species of Hermilius is provided.

A comparative ecological study on internationally important wetlands of Khoor-e-Kolahy and Tiab

Ecological study on Kolahy and 'flab estuaries were carried out during 1996-1997. Water and sediment sampling was done seasonally. In order to study the physical and chemical characteristic of the water, various animal fauna from different material niches including planktons and fish from water, benthousi from the sediment , and surface living animal such as Arthropod (Crabs) and Waterbirds were identified. I he result shoved, that water salinity of both estuaries was the same as the general salinity existing its the Persian Gulf water, and its variation is same IN those waters Minimum water salinity in both estuaries are seen during Bahairdan or early winter mooth(Jaa.), which is about 31ppt and Maximum is during .rirldlun.) or summer mouth at about 19 ppt. Dissolved otygen and pH are slime as the general Persian Gulf waters., Dissolve Oxygen being directly associated to temperature and its fluctuation is between 7- Sing/I and pH between 7.5-LS. The animals of both estuaries are almost similar having a sal factory species diversity . The birds of the region are often seasonal migrants , the maximum population of which occurs in winter season and the minimum during summer month. Nam coverage is richer in Tiab than Kolahy estuary, where in Kolahy a signal Mangrove tree is in exigence. 'Ile total coverage of Mangrove forest in Tiab is estimated about -29 hec.Both estuaries are included with in the international Ramsar Convention sites in 1971. Due to national importance of these estuaries inproviding refugee for various birds species and also hinting grounds and access traffic for local fishing vehicles, Actiog as an important access for various inhabitancy living with these area of the Persian Gulf. Due to importance or prawn aquacultur for the economical well being of local inhabitance, these areas provide a suitable grandees for prawn production. I-test statistics show, there are no significant difference among various invertebrate and vertebrate animals. In over all out look 21) phytoplankton genera, 21) zeoplankton genera 17 miafauna and 32 roaerofauna genera , 11 different species Carcineacearions and 119 species of walerbirds were identified with in the Tiab and Kolahy estuariesregioos. The X statistic show that the animal density is directly associated to season. Where density of miofauna and maerofauna in both estuaries are in maiticrourn during summer and the minimums existing during the winter season. In addition the bentic invertebrate population density in closlly association to birds population density since , the later, feeds on the former animals. Where the increasing in bird population density during the winter season, the bentic invertebrate animal population density decreases. The over all trend of animal population density in winter tend to increased towards the summer seasons, which this is due to climatic conditions of the region. The bird population on the contrary to other animals of both estuaries tend to increase from summer towards the winter seasons and which this bird population density is in maximum in winter with in the region.