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Mangroves are highly susceptible to oil exposure. Oil spills cause long-lasting mangrove loss, threatening their conservation and ecosystem services worldwide. This study aimed to explore the impacts of the Gulf War oil spill, which occurred between August 1990 and February 1991, on mangrove vegetation in the Persian Gulf and Oman Sea regions (Nayband, Qheshm, Bandar-Abbas, Sirik, Jask, Gabrik and Govatre mangroves). We utilized remote sensing technologies to investigate the potential changes in mangrove area and health in response to the oil spill. The analysis of historical Landsat-derived Normalized Difference Vegetation Index (NDVI) data revealed significant degradation in the Nayband, Qheshm and Bandar-Abbas mangrove, which were closest to the contamination source. Results indicated that the oil spill degrades the mangroves around 17.7 ha with poor or moderate greenness and health condition in Nayband mangrove site (Bidkhoon and Basatin). The analysis in Qheshm mangroves revealed that the oil spill had a notable effect on mangroves in Classes 2 and 3, causing them to transition into Class 1, which represents weaker mangroves in terms of health and greenness. Also, the Bandar-Abbas mangrove area experienced a significant decline across all classes around 25%, or 129 hectares. These mangroves experienced greater reductions in overall area as well as declines in vegetation health. In contrast, the mangroves along the northern coast of the Oman Sea showed no evidence of area reduction due to oil contamination. Landward mangroves in Iran, which have lower NDVI values and higher oil concentrations in the sediment, are most susceptible to being lost due to oil spills. These mangroves have revealed their resilience and ability to undergo rapid recovery within 5 years after the Gulf war because the Iranian coastal mangrove areas were largely untouched and undeveloped, which provided a favorable environment. Additionally, the high temperatures and intense solar radiation in the region created a suitable condition for the degradation of the oil, further contributing to the mangroves' recovery. This highlights the need for improved monitoring and conservation efforts to protect mangrove habitats, which are critical for supporting coastal communities and the broader environment. [ABSTRACT FROM AUTHOR]

The significant increase in the pollution of heavy metals and organic pollutants, their stable nature, and their high toxicity are gradually becoming a global crisis. In a recent study, a comprehensive assessment of the spatial distribution of heavy metals and total petroleum hydrocarbons (TPHs), as well as an assessment of their ecological risks in the sediments of 32 stations located in commercial and industrial areas (Mainly focusing on petrochemical and power industries, desalination plants and transit Ports) of Hormozgan province (East and West of Jask, Bandar Abbas, Qeshm, and Bandar Lengeh) was performed during 2021–2022. The sediment samples were digested with HNO3, HCl and HF solvents. The concentration of heavy metals was determined with furnace and flame systems of atomic absorption spectrometer. The concentration of heavy metals showed significant spatial changes between stations. The ecological assessment indices between the regions indicated that the stations located in Shahid Bahonar Port, Suru Beach, and Khor gorsouzuan had a higher intensity of pollution than other places and significant risks of pollution, especially in terms of Cr and Ni. The average contamination degree (CD) (14.89), modified contamination degree (MCD) (2.48), pollution load index (PLI) (2.32), and potential ecological risk index (PERI) (100.30) showed the sediments in the area of Shahid Bahonar Port, Suru beach and Khor gorsouzuan, experience significant to high levels of pollution, especially Cr and Ni. Using contamination factor (CF) and Geoaccumulation index (Igeo), Cr was considered the most dangerous metal in the studied areas. Based on the global classification of marine sediment quality for the concentrations of TPHs, the sediments of the studied stations were classified as non-polluted to low pollution. In all regions, indices of the PELq (General toxicity) and CF (Contamination factor) were much lower than 0.1 and 1 respectively, showing the absence of adverse biological effects caused by TPHs in sediments. It is necessary to consider comprehensive and impressive strategies to control and reduce pollution of heavy metals, especially in the areas of Shahid Bahonar Port, Suru Beach, and Khor gorsouzuan, so that the sources of this pollution are required to be identified and managed. [ABSTRACT FROM AUTHOR]

In this study, the relationship between dissolved oxygen reduction in the Gulf of Oman and changes in effective factors such as temperature and thermal stratification, exchanges with nearby water bodies, biological activities, chlorophyll-a concentration, and primary production was studied. The data used in this research were extracted from the measurement data available on global sites such as the World Ocean Atlas and SeaWiFS and MODIS satellite images. Comparing the average annual DO profiles in the Gulf of Oman showed a decrease in the upper 1000 m layer in 2010 compared to 1960. The DO reduction in the surface mixed layer was 0.4 mg/l and reached 3.7 mg/l at 100 m depth. At depths more than 100 m, the amount of change decreased and reached 0.1 mg/l at 1000 m. Due to the deoxygenation, the thickness of the surface layer with DO˃2 mg/l decreased from 150 m to 80 m. The results demonstrated that the drop in DO in the surface mixed layer was consistent with the decrease in gas solubility caused by the temperature increment in this layer. Regarding the severe reduction of DO in the layer below the surface mixed layer, it was shown that the strengthening of thermal vertical stratification and intensification of thermocline (0.01°C/m increase in thermal gradient) were the most important factors. [ABSTRACT FROM AUTHOR]

Fish are a significant dietary source of various minerals essential for human health. This study examined the mineral profile (sodium, potassium, calcium, magnesium, iron, zinc, copper, iodine, selenium, and chromium) and harmful trace elements (mercury, lead, cadmium, and arsenic) in different parts of the bigeye ilisha (Ilisha megaloptera), including the backbone, head, abdominal fin and viscera, caudal fin, and fillet, from the northern coast of the Oman Sea. Results revealed significant variations in element concentrations among different parts, with higher mineral levels often found in waste parts compared to the fillet. Most minerals were present in amounts exceeding human dietary requirements, suggesting that processing waste parts of bigeye ilisha could be beneficial as food or dietary supplements. Additionally, the levels of harmful elements-- mercury, lead, cadmium, and arsenic--were below permissible limits for human consumption. These findings support the potential for developing value-added products from bigeye ilisha. [ABSTRACT FROM AUTHOR]

In this investigation, the General Ocean Turbulent Model (GOTM) was used for the investigation of turbulent processes of a water column over a study site in the Oman Sea. The used method appropriately reproduces the main features of the study area, allows for a realistic view of the turbulence, and thus makes it possible to compare the Mixed Layer Depth (MLD) in all seasons. The MLD varies from 150 m in spring to 200 m in autumn. This simulation presented that the production of Turbulent Kinetic Energy (TKE) in the seawater column in the Oman Sea has seasonal changes. In the surface layer, TKE is small which is produced by low quantities of shear production, then it is conserved by the wind stress on the mixed layer and buoyancy production. In the deep layer, TKE is produced only by buoyancy. Calculated Prandtl number in all seasons presented that the turbulent diffusivity of temperature is dominant in most parts of water column, except in a thin layer which forms approximately between the depths of 150–200 m. [ABSTRACT FROM AUTHOR]

In the present study, the exploitation status of Babylon snail was evaluated by sampling four fishing areas of this species in the north of the Oman Sea (Iran) including Pasabandar, Bris, Pozm and Konarak from September 2021 to September 2022. In order to estimate the amount of catch per month, sampling was done by collecting statistics and information from the landing site, by counting at the place and sampling at the time. The amount of Babylon snail fishing effort and catch indicates that Bris and Pozm stations had the highest and lowest catch rate as well as fishing effort (day-boat) at the time of snail harvest (P<0.05). The average catch per fishing effort post Monson and per Monson time were 183 ± 79 kg and 117 ± 25 kg, respectively (P<0.05). In general, the fishing status of Babylon snail species has a fishing effort of 4569 days - boat fishing per year and the average catch per fishing effort (CPUE) of each boat is about 150 kg and the average catch per cage is about 0.59 kg. According to the calculations, the average of virgin biomass was obtained 971 (918-1047) tons, the average of maximum sustainable yield (MSY) less than 250 tons and maximum constant yield (MCY) less than 180 tons and total allowable catch (TAC) less from 220 tons, respectively. The amount of Babylon snails catches on the northern waters of the Oman Sea (Sistan and Baluchestan province) is more than 670 tons per year, that its seems to be higher than the optimal catch. [ABSTRACT FROM AUTHOR]

Background and Objective: Microplastic pollution due to its small size can be used by a wide range of marine organisms and accumulate mainly in their digestive system, as they have been found in the tissues of aquatic animals, including fish. Due to the nutritional importance of fish for humans, it is very important to check their contamination. The main purpose of this research is to investigate the presence of microplastics in skipjack tuna (Katsuwonus pelamis) in the Oman Sea. Materials and Methods: 17 pieces of skipjack tuna were used. After the biometry, dissection and isolation of the digestive system of the fish, the digestion and extraction of microplastics were done using KOH solution. Identification and counting were also done by a stereomicroscope equipped with a digital camera. FTIR spectrophotometric analyses were performed to investigate the polymers. Results: The total frequency and average frequency of microplastics are 331 particles and 19.4±7.3 particles per individual, respectively. String (64.35%) and pieces (28.7%) were the dominant forms in the samples. The highest color spectrum was assigned to red (28.7%) and the lowest to violet (1.51%). The largest number of identified microplastics had a size of 0.5-1 mm (53%). Analysis of particles by ATR-FTIR method showed that nylon polymer and polycarbonate were the dominant polymer particles. Conclusion: Microplastics are present in all samples. The abundance of microplastics in water, sediments and contaminated bait makes them easily available and swallowed by fish, which is most likely the main reason for the presence of microplastics in fish. [ABSTRACT FROM AUTHOR]

Diverse, abundant and well-preserved mollusk fauna are here reported for the first time from the eastern coast Makram area, where Upper Miocene (Tortonian) sediments of the Dar Pahn Unit crop out, representing shoreface tidal influenced deposits composed mainly of ligh-gray marls. Multiple articulated bivalves and completely preserved the gastropod and bivalve shells indicate little or no transport at all from the original habitat of the mollusk assemblage. A total of 313 specimens, from which 271 correspond to gastropods, were identified only at generic level, since the purpose of this contribution is to offer an introduction to this exceptionally well-preserved mollusk assemblage. Previous studies of the area include detailed nannoplankton biostratigraphy and the report of a balaenopterid cetacean. Future studies include the detailed identification of the specimens, along with sediment analysis in order to find protoconchs and offer an extended version of this introductory report. [ABSTRACT FROM AUTHOR]

Coastal areas represent the most vulnerable regions of the ocean. Thus, the identification and estimation of sedimentation rates in the sensitive coastal habitats of Qeshm and Lark islands were conducted during 2022-2023. The diving team identified three habitats consisting of natural structures in the north of Larak Island, characterized by the predominance of Acropora sp., and one habitat featuring flora and fauna originating from human-made structures (Doha Qeshm Jetty). These habitats, resembling those on Larak Island but on a smaller scale, were mapped using ArcGIS software 10.1. Three sediment traps were placed at 500-meter intervals in each station to cover each habitat comprehensively. The minimum and maximum sedimentation rates were measured at Larak Islands (St3) with 28 and Doha Qeshm Jetty with 196 (g/m2/day), respectively. Additionally, the minimum and maximum concentrations of suspended substances in the water column, ranging from 9.44 to 21.31 (mg/lit), were observed at these two stations during autumn. The freshness of Acropora sp. served as an indicator in all four habitats, potentially reflecting either the negligible impact of sedimentation rates on communities or the resilience of these communities to sedimentation during the study period. [ABSTRACT FROM AUTHOR]

In this study, sampling of commercial vessels of Afsoon 1 was carried out in July 2020, at a distance of more than 10 miles in longitude24 50 to 24 60 and latitude 61 03 to 61 05. At the time of the study, trawl fishing was done 13 times at different times, 8 times during the day and 5 times at night. The total catch during the study period was 12306 kg and 8720 kg were caught during the day (about 71%) and 3586 kg at night (about 29%). The average catch per fishing effort (catch per hour) of the target species was 201 kg (67%) during the day and 63 kg (33%) at night, and the average catch per fishing effort (catch per hour) discard species were 71 kg (28%) during the day and 100 kg (59%) at night (P<0.05). The mean catch per fishing effort (catch per hour) of bycatch fishing species at 18 kg during the day and 9 kg at night were not significantly different from each other (P>0.05). The Trichiurus lepturus species (64%) had the highest catch of target species, Epinephelus coioides species (53%) had the highest catch of bycatch fishing species and Ray fish (88%) had the highest catch of discard species. The Siganidae and Megalaspis cordyla species, appear to be active during the day and pipe fish, Anguiliformes and Belonidae species of night active. [ABSTRACT FROM AUTHOR]

The aim of this study is to develop different models of aquatic forecasting and try to predict yellowfin tuna catch in the southern waters of the country with minimum possible errors. The average catch (Yi ± S. D) and logarithm of catch (LogYi ± S. D) for the years 1997 to 2021 were 35,378 ± 13,744 tons (95% confidence interval 21,634 - 49,129 tons) and 4.51 ± 0.18 tons (95% CI The confidence interval was 4.33-4.69 tons), respectively. According to the Mann-Kendall test, the average catch has increased significantly during the mentioned period (over the last two decades) (Z = 3.80, P < 0.05). Different ARIMA combined prediction models (ARIMA, (p, d, q)) were tested based on the AIC index, and the ARIMA model (1, 0, 0) had the best fit with the change trend of yellowfin tuna in the southern waters of the country (AIC=- 24). The predict of yellowfin tuna catch results in the neural network (NN) models was show that feed forward neural networks (FFNN) have better performance than other models and with less error (MAE=0.02 and RMSE=0.03). Also, according to the results of ARIMA time series and neural network models, it can be concluded that feed forward neural networks simulate catch this species fish with higher accuracy than time series models. It seems, forecasting the trend of aquatic catch can be an important tool for fisheries managers and planners for better and sustainable management of aquatic resources and should be given more attention. [ABSTRACT FROM AUTHOR]

Today, por ts are regarded as the entry and exit gates of every country, and their proper performance and high efficiency can play a very decisive role in the prosperity of the economy and changes in the spatial structure of cities and hinterland areas. To have one of the important factors in the evaluation of ports is their geographical location, equipment and performance, which indicates the difference in the level of efficiency, productivity and development of ports and, by nature, cities and hinterland areas. The purpose of this research is to identify, analyze and level, capacity, facilities and capabilities of the coastal ports of the Persian Gulf and the Sea of Oman. The research method used in this research is descriptive-analytical using documentary sources and reliable internet sites. In order to rank the criteria and sub-criteria, the BWM model has been used, and the MABAC model is used to rank the development level of the ports. After a general review and comparison of the criteria and sub-criteria, among the coastal ports of the Persian Gulf and the Sea of Oman located in the Middle East region, 20 ports of Bushehr, Asalouye, Chabahar, Shahid Rajaei, Shahid Bahonar, Shahid Haqqani, Dammam, Doha, Hamad, Muscat, Rashid, Jabal-Ali, Al-Hamriya, Manama, Mina Salman, Sitra, Shoaiba, Shoveikh, Doha and Al-Ahmadi were selected for the purpose of conducting research. The findings of the research show that Jabal-Ali port, as the largest port in the Middle East and the world in the city of Dubai, is at the first level of development among the 20 compared ports, in terms of the criteria and sub-criteria examined; Therefore, it can be said that despite the fact that Rashid Port is considered as the oldest port in Dubai, Jabal Ali Port has been affected by internal factors such as oil revenues and government strategies and external factors during the last two decades. Like the regional and global forces such as container construction, it has the highest level of development. This issue has been able to affect the development of commercial, recreational and oil port infrastructures on the coast of Dubai metropolis. [ABSTRACT FROM AUTHOR]

Marine plants are good source of natural antioxidant compounds. Mangroves are a group of salt-tolerant marine plants of intertidal areas with numerous medicinal properties. In the present study, phytochemical analysis (steroids, alkaloids, phenols, flavonoids and tannins) and antioxidant properties (total phenolic content, DPPH free radical scavenging activity, reduction power and metal chelating activity) of methanolic extract of leaves, stem bark, and roots of mangrove species Avicennia marina was investigated. The mangrove samples were collected from the shores of Gwater Bay in the southeast of Sistan and Baluchestan province. Phytochemical analysis showed that all the tested compounds were present in the extract of mangrove leaves, except alkaloids. While in the stem bark extract, only phenolic compounds, flavonoids and tannins were observed and alkaloids and steroids were not detected. Alkaloids, phenols and flavonoids were discovered in the root extract. The assessment of the antioxidant properties showed that among different parts of mangroves, the highest amount of phenol (6.28 mg gallic acid/ g extract), free radical scavenging (59.18 %) and iron ion reduction power (absorbance at 700 nm: 0.37) was found in the leaves extract. Contrary to these two indicators, the highest amount of iron chelating activity (absorbance at 562 nm: 0.84) was found in mangrove root extract. The results of this research showed that different parts of the mangrove plant, especially its leaves, can be considered as a potential source of natural antioxidants.

The purpose of this study to develop a framework for investigating the catch trend and estimation of optimized catch limit of the P. homarus stock by collecting catch data in the northern waters of the Oman Sea. In this research, the landing catch data of the northern waters of the Oman Sea (Sistan and Baluchistan province) for more than twenty years (based on tons) have been collected from the Iranian Fisheries Organization (1997-2019). The average catch for this study period is 33±6 tons with a 95% confidence interval of 27-39 tons, and the amount of catch increased during the study period (R = 0.37). The average (95% confidence interval) for the intrinsic growth rate (r), maximum sustainable yield (MSY), biomass of maximum sustainable yield (BMSY), and carrying capacity (K) were obtained 0.56 (0.4-0.78) annually, 140 (120-170) tons, 156 (95-255) tons, 313 (192-510) per year, respectively. Based on the trends of B/BMSY and F/FMSY ratios, it can be said that the increase in fishing mortality and the decrease in available biomass started in 2014 and continues. This research shows that the annual harvest of this species has reached its maximum amount and measures should be taken to reduce the amount of catch and fishing effort. [ABSTRACT FROM AUTHOR]

Marine plants are good source of natural antioxidant compounds. Mangroves are a group of salt-tolerant marine plants of intertidal areas with numerous medicinal properties. In the present study, phytochemical analysis (steroids, alkaloids, phenols, flavonoids and tannins) and antioxidant properties (total phenolic content, DPPH free radical scavenging activity, reduction power and metal chelating activity) of methanolic extract of leaves, stem bark, and roots of mangrove species Avicennia marina was investigated. The mangrove samples were collected from the shores of Gwater Bay in the southeast of Sistan and Baluchestan province. Phytochemical analysis showed that all the tested compounds were present in the extract of mangrove leaves, except alkaloids. While in the stem bark extract, only phenolic compounds, flavonoids and tannins were observed and alkaloids and steroids were not detected. Alkaloids, phenols and flavonoids were discovered in the root extract. The assessment of the antioxidant properties showed that among different parts of mangroves, the highest amount of phenol (6.28 mg gallic acid/g extract), free radical scavenging (59.18 %) and iron ion reduction power (absorbance at 700 nm: 0.37) was found in the leaves extract. Contrary to these two indicators, the highest amount of iron chelating activity (absorbance at 562 nm: 0.84) was found in mangrove root extract. The results of this research showed that different parts of the mangrove plant, especially its leaves, can be considered as a potential source of natural antioxidants. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the bioaccumulation of heavy metals (copper, zinc, and lead) and chemical compositions (fat, protein, moisture, and ash) in the Parastromateus niger muscle of the Oman Sea in pre-monsoon and post-monsoon. An atomic absorption spectrophotometer was used to determine heavy metal concentrations in fish muscle tissue. Chemical composition contents were measured using the Association of Official Analytical Chemists (AOAC) methods. Zinc was the most abundant heavy metal in two seasons (0.077 ± 0.005 μg/g), followed by copper (0.033 ± 0.005 μg/g) and lead (0.015 ± 0.005 μg/g). The mean concentrations of all heavy metals of muscle in pre-monsoon were higher than in post-monsoon. The concentrations of Cu, Zn, and Pb were lower than the maximum permissible limits (MPL) of international standards for human consumption established by FAO, FAO/WHO, WHO, and MAFF. The protein and fat content in fish muscle collected in pre-monsoon was higher than in post-monsoon. A significant difference between protein, fat, moisture, and ash values was recorded in two seasons (P < 0.05). The human health risk of heavy metals was evaluated according to the United States Environmental Protection Agency (USEPA) standards. The estimated daily intake (EDI) of each heavy metal in two seasons was lower than the tolerable daily intake (TDI). THQ (target hazard quotient) and TTHQ (total target hazard quotient) values were lower than the threshold limit of 1.0, indicating a non-carcinogenic risk for consumers. TR (target carcinogenic risk) value for Pb was much lower than the unacceptable risk level (10−4); therefore, the consumption of muscles of Parastromateus niger did not significantly pose a human health risk. [ABSTRACT FROM AUTHOR]

Scale and otolith morphology and morphometry of Indian oil sardine Sardinella longiceps (Clupeidae) were investigated and described using light and scanning electron microscopy from eight different body regions for scales and the right and left otoliths. Scales of the Indian oil sardine show general characteristics of the other studied clupeids sand that are easily distinguishable from other fish groups, by having striae in the posterior field. The studied cycloid scales of S. longiceps were classified into three types based on the overall shape including circular (e.g. true circular and cordate), pentagonal and quadrilateral in the different body regions. The circular shape was the most common shape (87.5%), while the quadrilateral and pentagonal forms constituted 6.25% each. The results also showed that the relative scale size (J‐index) plays a desirable contribution in separating the examined populations. The results showed that the mean (or relative) scale size for all the eight regions in the Oman Sea population is larger than the Arabian Sea population. Also, another scale variable, the scale shape index (Si index), demonstrated variation (a mean of 0.86 to 1.1) in different regions of both populations from the Oman and Arabian Seas. Interestingly, here, we found that scale characters of S. longiceps not only differ from its other congeneric species, but also differ in the populations from both sides of the Oman Sea (Iran and Oman) and the Arabian Sea. It shows a positive signal for the presence of different taxonomic and management unit in the Oman and Arabian Seas. The idea should be approved by using integrated molecular and morphological traits. The otolith morphology of S. longiceps from the Oman and Arabian Seas was more conservative than the scales, which can be due to its function actin primarily as a balance organ and also enhancing hearing. The overall shape of S. longiceps otolith was lanceolate, with an elongated morphology and a well‐developed rostrum, an ostial sulcus acusticus that opens to the anterior/ dorsal margin. These morphological characters are also found in the Iranian population of S. longiceps. However, otolith displayed variation in biometric parameters among two populations and left and right otoliths and the RRL parameter were important characters to discriminate the Oman and Arabian Sea populations. Thus, the structural/biometrical variability of the otoliths may be used for population distinctness, especially in water bodies with various environmental factors, and the otolith has turned out to be a useful tool to track the life history of teleostean fishes in environments with physicochemical gradients. [ABSTRACT FROM AUTHOR]

Cysts produced by dinoflagellates act as the seeds involved in the initiation of algal bloom through blooming and at the end of bloom through the reformation of cysts. Therefore, they are of great importance in environmental studies. In this study, sampling of sediments in the Gwater Bay, located on Iran's southeast coast and the northeast of the Oman Sea, was done in the spring (premonsoon) and summer (post-monsoon) of 2013 to examine the distribution and abundance of dinoflagellate cysts. Twentyfour species belonging to 12 genera of the dinoflagellate cysts were identified for the first time in this area. The results of ANOVA indicated no significant difference between the abundance of cysts in different seasons. A study of the Shannon index in this area revealed a high diversity and abundance in the study area. In this study, 8 species of dinoflagellate were found as potentially toxic species. [ABSTRACT FROM AUTHOR]

The Persian Gulf and the Oman Sea contain a variety of aquatic species. Among which, Parastromateus niger (Bloch, 1795), Black pomfret fishes are very important and, one of the tuna fish that has increased its catch in recent years. In this research during April to March 2020, trend catch and demographic characteristics and demographic characteristics of Black pomfret were estimated by collecting information from 4 catchment areas in the southern waters of Oman Sea (Sistan and Baluchestan) including Pozem, Konark, Beries and Pasabandar. In this study, more than 14,000 fish at the research stations were biometric and the growth parameters were infinite length of L∞=54 cm, growth factor K=0.36 (yr-1 ), natural mortality M=0.52 (yr-1 ), mortality and mortality (yr-1 ), F=1.27, total mortality (yr-1 ), Z=1.79 and exploitation coefficient (yr-1 ), E=0.71, and the time zero was -0.39 for the years. This study shows that the annual harvest of Black pomfret stock has reached its maximum and any increase in fishing effort will affect this stock and will reduce the amount of exploitation in the long run. [ABSTRACT FROM AUTHOR]

Introduction In the early centuries of Islam, the Oman Sea achieved a global position. So, the trade economy has played the most important role among surrounding lands of Oman Sea. In this period, the three districts of Kerman, Makran and Oman had active economic relations with each other. This economic boom in the early centuries of Islam, centered on the Sea of Oman, made the security of trade routes in these areas important for the rulers, including al-Buwayh. Az-Dawla's campaign to the southeast has shown the importance of these roads which are leading to the Sea of Oman. Accordingly, this study aims to show the trade economy of the lands around the Oman Sea with emphasis on the three regions of Kerman, Makran and Oman. Methodology This article uses library and descriptive and analytical method. Therefore, historical data on the trade status of the lands around the Oman Sea have been collected. Finally, the collected data from first-hand historical sources have been analyzed and explained based on research questions. Discussion In the Sassanid period, which was the last government of ancient Iran and Sassanid ruled over the lands around the Oman Sea generally and the three regions of Kerman, Makran and Oman particularly. Kerman and Makran during this period were considered important lands in the trade route of the southeast of the empire. Additionally, the land of Oman was also important due to its strategic position, which was the port and position of ships in the Indian Ocean. As the Shah of Oman had ties with the central government of Iran during the Sassanid period, especially since the Bani Azd tribe were among the tribes that cooperated with the Sassanid government. At the end of the Sassanid rule, we see insecurity in southeastern Iran that affected the trade situation and trade relations in the lands around the Oman Sea, as in the late Sassanid era, the central government was not able to deal with the insurgents. With the beginning of the conquests by the Muslim Arabs, Oman was one of the first lands to be conquered. The Muslims used this region as a naval base to occupy the regions of Iran, especially Kerman. The conquest of Makran also took place shortly after the conquest of Kerman, although it did not have wealth, as mentioned in the sources, but it accelerated trade relations with other regions, including Oman and Kerman. During this period, which coincides with the first centuries of Islam, trade relations increased significantly even compared to the Sassanid period. This factor made the Oman Sea and the surrounding lands as one of the most important commercial and commercial areas in the first centuries of Islam. There were numerous factors which played a role in this, and perhaps the same geographical conditions and climatic characteristics of these areas can be considered important. These almost identical climatic conditions, as well as the disappearance of political borders that previously hindered free trade, brought economic prosperity to the lands around the Oman Sea. Therefore, with this explanation, one of the most important periods of economic prosperity and prosperity of the Oman Sea and the surrounding lands should be considered in the first centuries of Islam. Beside these factors and despite reciprocal economic relations of those three regions during this period as well as cultural relations and migrations in these areas in the early centuries of Islam, the migrations of famous Arab tribes such as Bani Azd and Al Mahlab are also considerable. According to sources, the Mahlab family settled in Jiroft, and the Bani Azd tribe, which had a successful pre-Islamic commercial activity, settled in Kerman and Makran. The presence of these tribes caused cultural and economic relationships between them. As a result, trade relations also increased. However, the main reason for the prosperity of these areas was the special place of the Oman Sea in the early Islamic centuries. This prosperity of the sea should be seen in its ports in the first centuries of Islam. As the ports of Hormoz, Tis, Sohar in the first centuries of Islam played a pivotal role in the commercial economy of these areas. These trade relations of the ports around the Oman Sea with the Persian Gulf ports such as Siraf and Basra and their Yemeni ports led to a sea trade centered on the Oman Sea. The location of the Oman Sea along the Indian Ocean expanded the commercial range of ports around the Oman Sea and was the center of world maritime trade during this period. Although the lands around the Oman Sea flourished in terms of trade relations during this period, the factor that influenced this trade was different groups. During this period, along the land routes leading to the Sea of Oman, the Kharijites, the Qafs, the Jashkians, the Qatari and the Qarmatians, and the pirates challenged its security. The Kharijites, the Qafs and the pirates probably considered as important groups, as these three groups played an active role due to their active presence in the trade routes of the lands around the Oman Sea. The Kharijites, who were present in all three lands of Kerman, Makran and Oman, expanded their influence in other lands with the rise of power and the formation of the government in Oman. It was the insecurity of these trade routes. Although the Qafs did not have Kharijite organizations and were mostly known as local bandits, their successive wars with the rulers of Al-Buwayh show that they had a significant force that was able to secure the trade routes from Hormuz to Kerman, which is the main highway. The third group, after the Kharijites and the Qafs which played a role in the insecurity of the trade routes around the Sea of Oman, were pirates. The pirates, based on the island of Saqqara, were a significant problem for trade and trade relations at sea with the equipment at their disposal, as sources indicate their active presence on trade routes to the Oman Sea. With this description, it can be said that this research, with a descriptive and analytical approach and a library method, seeks to show the course of trade relations between the three regions of Oman, Makran and Kerman in the first centuries of Islam. Conclusion The results of this study indicate that proximity to the sea (Oman Sea and Persian Gulf), creating security and laying sea and land routes (especially during the Buwayhid period), migration of Arab tribes, trade in precious stones, trade in aromatic materials, Establishing security through the suppression of bandit groups in the trade routes of the lands around the Oman Sea has been one of the most important factors of economic prosperity in the three regions of Oman, Makran and Kerman. Also, the security of trade routes leading to the Oman Sea has been important due to the economic prosperity of these areas.

Bisphenol A (BPA) is an endocrine disrupter with several adverse effects on human health and the natural ecosystem. BPA could be accumulated in marine environments and released into the food chain. The present study measured the concentration of BPA in 20 seawater samples, 128 fish as well as 20 urine samples of fishermen. Four highly used fish species including Silver pomfret (Pampus Argenteus), Tigertooth croaker (Otolithes ruber), Longtail tuna (Thunnus tonggol), and Stripped piggy (Pomadasys stridens) were purchased from the markets of coastal cities of the Persian Gulf and the Oman Sea. Measurement of BPA was conducted using GC–MS. We estimated the health risk attributed to BPA exposure for fish consumers and skin contact with seawater in the studied areas. The maximum and minimum mean BPA concentrations were measured in Longtail tuna (11.55 ng/g) and Silver pomfret (2.99 ng/g), respectively. Also, the concentrations of BPA in the urine samples ranged from 1.58 ± 0.82 to 2.64 ± 0.62 μg/L. The lowest and highest mean concentrations of BPA in the seawater samples were estimated to be 0.015 ± 0.008 μg/L in Chabahar and 0.038 ± 0.008 μg/L in Bushehr, respectively. Urinary concentration of BPA was significantly associated with the age and BMI of fishermen (P < 0.05). The hazard quotients (HQs) in children was higher than that of adult one. HQderm was estimated more than 1; however, the measure of HQing of fish was negligible. It could be concluded that there is a risk of unhealthy conditions due to dermal contact with BPA, especially in fishermen and their families. [ABSTRACT FROM AUTHOR]

Awareness of the amount of aquatic stocks in each water source is one of the first and most basic information needed to manage of fishery stocks. The Babylon snail species has commercial and export value and its catch has increased in recent years and has not been studied yet. In the present study, the exploitation status of Babylon snail was evaluated by sampling four fishing areas of this species in the north of the Oman Sea (Iran) including Pasabandar, Bris, Pozm and Konarak from September 2021 to September 2022. Biometric analysis was performed on a total of 2779 Babylonian snail specimens. The mean length (standard deviation) and weight (standard deviation) of total snails were 34 ± 5 in the range of 19 - 64 mm and 12 ± 5 in the range of 2 - 66 g, respectively. Growth and mortality indices include infinite length (mm) L∞ = 71, growth coefficient K = 0.35 (yr-1 ), natural mortality M = 0.5 (yr-1 ), fishing mortality F = 1.75 (yr-1 ); Total mortality was calculated Z = 2.25 ± 0.29 and exploitation coefficient E = 0.78. Babylon snails have a recruitment in all months of the year and have two major recruitment peaks during the year. The Production per biomass (P/B) 2.15 ± 0.23 in the range of 2.38 - 1.92 and the average annual production is 12 ± 3 per year in the range of 9 - 15. The present study showed that the exploitation coefficient of this species was not desirable and it should be in order to maintain and sustain fishing of this species, appropriate measures should be considered, including reduction of exploitation. [ABSTRACT FROM AUTHOR]

Most fishermen use traditional methods to identify areas with fishing potential. Increasing demand for fish and the need to exploit marine resources in a cost-effective manner and reduce human activities have made the introduction and application of new methods important considerations. The use of remote sensing in fishing leads to successful fishing and reduces the cost of fishing and human activities. In this research, we have tried to identify the distribution of Yellowfin tuna in the Oman Sea using Remotely Sensed system and draw a map of their possible presence. For this purpose, the distribution patterns of tuna fishes were studied through catch data and monthly remotely sensed data (sea surface temperature, chlorophyll-a, sea surface heights, salinity and wind speed) for the years 2016 and 2017 in the Oman Sea using GIS and multi-criteria evaluation. The results showed use of remotely sensed data to determine the spatial and temporal distribution patterns of Yellowfin tuna is more than 70% accurate. By studying, the output of the catch distribution map and the test data was determined the proposed model is of optimal power for identifying Yellowfin tuna. On this basis, it can be mentioned that remotely sensed data could show potential fishing zone with a least error. Therefore, in future studies, the use of remotely sensed data for location of fishing and fishermen guidance is suggested, Also the results of this research could help fishery managers to ecosystem fisheries based on management and reducing the fishing effort for fish finding. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate heavy metal (HMT) accumulation in some commercially pelagic (Scomberoides commersonnianus, Rastrelliger kanagurta, Saurida tumbil) and demersal fish (Parastromateus niger, Alepes melanoptera, Nemipterus japonicus, Alepes melanoptera) of Oman Sea. Fish samples were collected by trawl from inshore area of four stations along Chabahar bay. The heavy metal (Ni, Cr, Hg, Cd, Pb) concentrations in the muscle tissue of the fishes were assayed. In addition, the relationships between the level of heavy metal accumulation in fish tissue and fish size were studied. The demersal species accumulated more heavy metals compared to pelagic fishes (p < 0.01). Both in pelagic and demersal fishes, the rate of metal accumulations was different depending on fish species. In addition, the trophic level affected tissue muscular metal concentrations. Both in pelagic and demersal fishes, the carnivorous and euryphagous species accumulated more metals compared to phytoplankton and herbivorous fishes (p < 0.01). In most cases, negative relationships were observed between fish size (length and weight) and the metal accumulations (p < 0.01). However, some positive correlations were also observed in Hg, Pb and Cd concentrations with size in Psettodes erumei and Parastromateus niger (p < 0.01). In conclusion, the different patter of metals accumulations may be attributed to the differences in feeding behavior, metabolic activity and habitat. In this study, except Cd and Cr, the concentrations of all heavy metals were in the safe range and were below the hazardous limits recommended by the EC (2001) and USFDA. [ABSTRACT FROM AUTHOR]

Mangroves are known for providing multiple ecosystem services and critical habitats for diverse species and are one of the most threatened ecosystems by human activities and climate change. However, little is known about their distributional patterns. In this study, the distribution of the dominant species, Avicennia marina was examined in the context of climate change to identify conservation priority objectives at the spatial and temporal scales on the southern coast of Iran. A maximum entropy model was used to predict the potential distribution of the mangrove forest in the current situation and forecast its future (2070: RCP 8.5, CCSM4). The result revealed that the potential distribution for the mangroves will decrease in the future and probably two habitat patches remain, one patch in the middle of the coasts of the Persian Gulf and another patch in the middle of the coasts of the Oman Sea. Annual mean temperature, temperature annual range, and annual precipitation were the most important determinants of the mangrove distribution. The findings can be used as a theoretical basis to manage and protect the habitat of mangroves in Iran. HIGHLIGHTS Mangrove forests in Iran are found on the sheltered coasts, estuaries, and some near-shore islands of the Persian Gulf and the Oman Sea and Avicennia marina is the dominant species.; Mangrove habitat distribution in the southern coasts of Iran under climate, biochemical, and environmental conditions were predicted.; The potential distribution for A. marina will decrease under RCP 8.5 by 2070.; Eastern parts of the coasts of the Persian Gulf and the Oman Sea are the most suitable areas for mangrove distribution.;

This paper investigates the deterministic tsunami hazard scenarios to assess the potential impact on the Qurayyat coast, northeast Oman. It assesses the maximum tsunami hazard characteristics with a focus on the zoning of tsunami hazard related to the human ability to stand within the inundation areas. Additionally, probabilities of buildings damage and small vessels loss are presented using fragility functions adapted from published studies of the 2011 Great East Japan Tsunami. Two worst-case credible tsunamigenic scenarios from Makran Subduction Zone (MSZ) were selected: 7.2Mw and 8.8Mw earthquake scenarios from western and eastern segments of the MSZ, respectively. A validated nonlinear shallow water numerical code with nested grids is used to simulate the tsunamis for each scenario over a 15 m-resolution grid for the Qurayyat region. Our results show that 8.8Mw earthquake corresponds to the maximum probable tsunami scenario posing the most severe threat. This scenario causes tsunami waves reaching 4.9 m and leads to a maximum runup height, maximum flow depth, and maximum inundation of 5.2 m, 3.8 m and 1.5 km, respectively. Furthermore, the tsunami hazard zoning for human stability suggests five hazard levels, ranging from “very low” to “very high” and the flooded buildings are classified into six damage levels, ranging from “minor” to “washed away”. The probabilities of buildings damage are high for minor and moderate damage levels. The vessels are classified based on their weight and location of motor. Obtained probabilities of vessels loss show that the outboard motor vessels would suffer greatest loss than inboard and the heavier ones.

Many ecologically important and valuable fisheries marine species have been misidentified in terms of both the statistical data and market demand. Correct identification at the species level and the population genetic structure of the orange-spotted grouper (Epinephelus coioides), a precious fish in the Persian Gulf and the Oman Sea, was tested using mitochondrial cytochrome oxidase subunit I (DNA barcoding) and D-loop sequencing. The results revealed that the Epinephelus species found in the region, including E. coioides, E. bleekeri, E. polylepis, and E. chlorostigma were all mistakenly grouped together and identified as only E. coioides. Moreover, the analysis of molecular variance (AMOVA) of E. coioides samples using the D-loop showed a significantly unique genetic structure (ΦST = 0.068, p < 0.001) within the E. coioides population throughout the Persian Gulf and the Oman Sea, with the pairwise genetic difference between sampling locations in UAE and the Iranian coast. Moreover, D-loop sequences analysis showed two distinct haplotype groups scattered among the sampling locations, which did not correlate with the geographic distance between the sampling locations. These findings indicate that the issue of misidentification should be highlighted in the management and conservation of E. coioides. As this type of misidentification is likely to happen to other threatened marine species as well, the efficacy of using genetic markers for the correct identification, both at the species and the population level, is vital. [ABSTRACT FROM AUTHOR]

The combined effect of climate change and steadily increasing seawater demand for industrial and domestic purposes in the Arabian Gulf region has a significant impact on the ecosystem in this region. Additionally, this effect may reduce the efficiency and increase the operating costs of industrial facilities that utilize seawater for cooling and other purposes. In this context, it is important to know various statistical characteristics of the sea surface temperature (SST) and their trends, in addition to the mean climatological characteristics. The analysis conducted in this study utilized a 17-year Group for High Resolution Sea Surface Temperature Level 4 dataset of 0.01 × 0.01° spatial resolution. First, the dataset was compared against a 2-year seawater temperature measurements at the ten offshore buoys in the relatively shallow coastal waters of the United Arab Emirates between Ras Ghumais and Dubai, which showed a reasonably good agreement between the two datasets, with the estimated root mean square deviations ranging from 0.5 to 0.9°C. Subsequently, several statistical SST characteristics were calculated. The trend analysis showed not only positive tendencies in the mean SSTs of up to 0.08°C/year in the northern Gulf, but also the trends in the annual percentile exceedances, particularly the 95th percentiles (near-maximum SSTs), which increased by approximately 0.07°C/year in the western United Arab Emirates and eastern Qatar waters. On the contrary, the 5th percentiles (near-minimum SSTs) decreased by up to 0.1°C/year, especially in the waters around Bahrain, Qatar, and the western United Arab Emirates. These results indicate that extreme hot and cold SST events in the Gulf are becoming more frequent and more extreme than before.

Many ecologically important and valuable fisheries marine species have been misidentified in terms of both the statistical data and market demand. Correct identification at the species level and the population genetic structure of the orange-spotted grouper (Epinephelus coioides), a precious fish in the Persian Gulf and the Oman Sea, was tested using mitochondrial cytochrome oxidase subunit I (DNA barcoding) and D-loop sequencing. The results revealed that the Epinephelus species found in the region, including E. coioides, E. bleekeri, E. polylepis, and E. chlorostigma were all mistakenly grouped together and identified as only E. coioides. Moreover, the analysis of molecular variance (AMOVA) of E. coioides samples using the D-loop showed a significantly unique genetic structure (ΦST = 0.068, p < 0.001) within the E. coioides population throughout the Persian Gulf and the Oman Sea, with the pairwise genetic difference between sampling locations in UAE and the Iranian coast. Moreover, D-loop sequences analysis showed two distinct haplotype groups scattered among the sampling locations, which did not correlate with the geographic distance between the sampling locations. These findings indicate that the issue of misidentification should be highlighted in the management and conservation of E. coioides. As this type of misidentification is likely to happen to other threatened marine species as well, the efficacy of using genetic markers for the correct identification, both at the species and the population level, is vital.

Chl a is the main pigment of phytoplankton, which is an indicator of phytoplankton biomass and reflects the primary production in the marine environment. In this study, level 3 (4 km) data of Chl a concentration of Persian Gulf and Oman Sea for the period of 2003- 2018 were used. The data was converted to raster format in ArcGIS10.5 environment and then the numerical values of each pixel were extracted in R (version 4.0.2). Missing data were observed in Chl a data, to solve this problem, DINEOF algorithm was applied and non-parametric Mann-Kendall and Sen’s Stimulator tests were used to analyze Chl a concentration trends. The results showed that the maximum concentration of Chl a is in September (0.09 to 18.75 mg / m³ ) and October (0.23 to 18.03 mg / m³ ) and the minimum concentration of Chl a in May (0.22 to 5.74 mg / m³ ) and June (0.20 to 5.12 mg / m³ ). The trend of Chl a concentration variability over the study period was negative in most areas and not significant. These analyses provide an overall description of Chl a concentration variability in the Persian Gulf and Oman Sea based on satellite observations; however, further investigations based on in situ observations are needed to achieve better understanding of the patterns of of Chl a concentration alterations. [ABSTRACT FROM AUTHOR]

In this study, the proximate composition and amino acid profiles of golden trevalley fillets from the Oman Sea in summer and winter were investigated. After sample and preparation the fillet of 36 fish, their moisture, fat, protein, ash and amino acid profiles were measured using high performance liquid chromatography method after acid and alkali hydrolysis. The total amount of essential amino acids in winter (10.624±0.324 g/100 g meat) was significantly higer than summer content (p<0.05). Histidine, lysine, phenylalanine, aspartic acid, glutamine and glycine showed significant differences in summer and winter (P <0.05). Glutamine rate was 3.293±0.05 and cysteine was 0.03 g/100 g meat, showd the highest and lowest amino acids, respectively. The ratio of essential to non-essential amino acids in winter was significantly different in comparison to summer (P <0.05). The ratio of leucine to isoleucine was higher than 1.9 in both seasons. Consumption of gold trevalley meat is suggested based on its high quality in terms of nutritional value in both seasons. Analysing its chemical index in winter and summer, expect the histidine, providing the essential amino acids of adults. [ABSTRACT FROM AUTHOR]

Oman Sea region is a major gateway for international and local shipping. Metal pollution of aquatic environment is primarily caused by such shipping and industrial activities. Agricultural runoffs are also of concern. Seaweed contamination with heavy metals in this area is therefore a distinct possibility. We examined seaweed of Oman Sea for heavy metal content and potential risk of its consumption to the public. During winter of 2019, water, sediment, and seaweed were collected along twelve stations on the coast of Oman Sea. Triplicates of each sample were analyzed for metal content by atomic absorption spectroscopy. Biomarkers of metals in seaweed (metallothionein and phytochelatin) were also analyzed. A significant positive correlation exists among levels of Zn, Ni, Pb, Cr, Cu, and Fe in water, sediment, and seaweed (P < 0.05). Cadmium correlations were weak. The highest levels of metallothionein and phytochelatin were found in brown and red seaweed (118.6 µg/g wet weight, 16.4 amol/cell; 111.4 µg/g ww, 12.1 amol/cell), respectively. For nickel and lead, human consumption of red, brown, and green seaweed was associated with "some health hazard," with a target hazard quotient of > 1. We conclude that concerns over heavy metal contamination of some parts of Oman Sea are valid, and we invite policy makers to implement measures for protection of public and environment from metal toxic effects in the region. [ABSTRACT FROM AUTHOR]

The ancient region of Makran is located in the southeast of the Iranian plateau and on the northern shores of the Makran Sea, whose borders stretch from Pars and Kerman in the west to Sindh in the east. This vast area was limited to Khorasan and historical Sistan from the nort This region has a valuable history of several thousand years and civilization and a special geographical location. The South Sea of ​​Iran has been called the "Sea of ​​Makran" for centuries due to its proximity to the land of Makran and has played an important role in the events in the south and southeast of Iran and its ports have long had a privileged commercial position.The passage of merchant ships and caravans carrying goods from India, China, Yemen, the Red Sea, and the east coast of Africa to the eastern regions made it one of the busiest areas for maritime and land trade. Makran cities such as the port of Tiz Faraj, Bampur, Cage, etc. were considered as important anchorages and rest areas of these roads.In this article, an attempt is made to examine the historical background of the Makran Sea using historical and geographical sources, and the reason for changing the historical and Iranian name "Makran" to "Oman" after centuries, along with the role of British colonialism in this change. Investigate and find out why, since the opening of the colonial powers to all parts of the world, including Central Asia, many countries have changed their names and historical and geographical declarations with direct intervention, and the historical name "Makran Sea" has been removed from new historical and geographical documents. And instead the nameless and unprecedented name was "Sea of ​​Oman".

The purpose of this study was to use the DINEOF algorithm to fill in the missing data points in the satellite imagery of chlorophyll a in the surface waters of the Persian Gulf and Oman Sea. In this study, level 3 data (spatial resolution of 4 km) of chlorophyll a concentration obtained from MODIS sensor in the period 2003 to 2020 in the Persian Gulf and Oman Sea (extracted from NASA site) were used. Some images had no product points in some months of the year. Images with missing products (gaps) of chlorophyll a concentration in the Persian Gulf and Oman Sea were reconstructed using rtsa.gapfill software package and DINEOF algorithm in R software. Finally, to evaluate the accuracy of the DINEOF algorithm, parameters such as RMSE, MSE, MAD and SNR have been calculated. The original maps (with gaps) of chlorophyll a concentration showed that highest amount of lost product was in July 2009 and 2015. Assessing the accuracy of the reconstruction, it was found that the reconstruction of the missing data was done well by the algorithm (for example, in July 2014, the calculated parameters are as follows: R2 = 0.83, RSME = 0.34, MAD = 0.14 and 0MSE =0.10). The results showed that the implementation of DINEOF algorithm in R software to reconstruct the missing products in chlorophyll a images is an efficient, rapid and successful method. Reconstructed chlorophyll a products can be used for applications such as detecting algal blooms as well as proper fisheries management. On a long-term scale, comparing lost products with reconstructed ones helps control the quality of satellite data. [ABSTRACT FROM AUTHOR]

Abstract Iran has faced with water scarcity problem for a long time. There is a strong tendency to desalinate seawater from Oman or the Caspian Sea as intake seawater and transfer it to central parts of the country. These projects face significant technical, economic, and environmental challenges. In this work, utilizing available economic theories about single-stage reverse osmosis (RO) desalination plants, the cost analysis of a conceptual plant with a production capacity of 200,000 m3/day, was accomplished assuming the use of Oman and Caspian seawater as feed. The effect of important parameters such as applied pressure, recovery ratio, total salt content of the feed, and produced water and the temperature has been studied theoretically. The results show that under the same working conditions, the final product price per cubic meter of freshwater from the Caspian Sea is $ 0.69 versus $ 1.24 for the Oman Sea, which is about 50% cheaper. The lower salinity of the Caspian Sea compared to the Oman Sea is the main reason, which lead to reduce in the capital cost of the RO membrane (62% difference), cost of the intake and pretreatment (20%), and cost of membrane elements replacement (13%) regardless of water transfer cost.

Wind-wave characteristics are one of the most important factors in the design of coastal and marine structures. Hence, accurate estimation of wave parameters is crucial. In this paper, we examined the performance of a third-generation spectral wave model, MIKE 21 SW, in estimating wave parameters in the Iranian southeastern coasts over 1 year in 2016 using unstructured triangular mesh. The simulated wave conditions at the southern open boundary and the wind field variable in time and space of the Weather Research and Forecasting model with a spatial resolution of 0.1 and a temporal resolution of 1 hr were used for evaluating the model. To improve the model's performance, it was calibrated and validated by adjusting white-capping coefficients. The output data including significant wave height (Hs), peak wave period (Tp), and mean wave direction were compared with the data measured by acoustic Doppler current profiler at three stations of Pasabandar, Pozm, and Meydani on the southeastern coast of Iran. The results revealed that the scatter index for Hs at three stations after calibration was 0.232, 0.363, and 0.684, respectively. Moreover, the results for mean wave direction were 0.149, 0.181, and 0.288, respectively. The mean model errors for Hs were 0.003 m, 0.233 m, and 0.399 m, respectively, and this error was typically calculated for Tp and mean wave direction at Pasabandar station 0.12 s and 3.80°, respectively. The finding shows a more accurate prediction of Hs estimation with an appropriate correlation coefficient in three stations with a low bias and upstream. Comparison of the period of modeling waves with measurement data shows the appropriate accuracy of modeling results. According to the climate modeling results, waves from the north wind (Shamal wind) with periods of less than 8 s and waves from the southwest (Monsoon) with periods of more than 10 s are well distinguishable. [ABSTRACT FROM AUTHOR]

Myctophids are one of the most important and valuable resources of fish in the waters of the Oman Sea. Considering the economic aspects of its harvesting has an important role in catch management and profitability of fishing vessels. In this study, the economic profitability of different length classes of lanternfish (Benthosema pterotum) fishing vessels was investigated using Internal Rate of Return (IRR) in northwestern waters of the Oman Sea from April 2016 to March 2017. Lanternfish trawler vessels were classified in four length classes including 35-40 m (A class), 40-45 m (B class), 45-50 m (C class), and more than 50 m (D class). IRR index of vessels in each length class was calculated with consideration to the shipping costs and income of selling fish. Mean IRR (±SD) in one year and A, B, C, and D ship classes were obtained as 41±35, 55±55, 40±36, 41±28, and 35±28%, respectively. Results of this study showed that active lanternfish fishing ships have an appropriate internal rate of return and low investment risk in waters of the Oman Sea, and C ship class (45-50 m) showed the best internal rate of return and the lowest investment risk among four classes of lanternfish fishing ships. Results of this study can be used to improve the harvesting management of lanternfish resources and consequently, organize the active fishing ships in the waters of the Oman Sea.

This study was performed to determine the chemical compositions and heavy metals in the muscle of Scomberomorus commerson from the Oman Sea, during the two seasons, pre-monsoon and postmonsoon in 2018. The protein, fat, moisture, and ash contents were determined by AOAC (Association of Official Analytical Chemists) methods. Heavy metal (Zn, Cu, and Pb) analyses were performed by atomic absorption spectrophotometer after acid digestion. There were significant differences between protein, fat, moisture, and ash values in muscle tissue in two seasons (P< 0.05). The highest content of protein (22.53±2.09%) and fat (4.15±1.25%) was recorded in pre-monsoon. The mean concentrations of heavy metals (μg g-1dw) in muscle tissue were 0.08-0.05 for Zn, 0.04-0.02 for Cu, and 0.02-0.01 for Pb in the pre and post-monsoon, respectively. The accumulation of heavy metals in muscle followed the Zn>Cu>Pb. The amounts of Zn, Cu, and Pb were below maximum permissible limits (MPL) recommended by international standards (FAO, FAO/WHO, and MAFF). Results revealed that estimated daily and weekly intakes of Zn, Cu, and Pb were far below the permissible tolerable daily intake (PTWI) recommended by FAO/WHO. Therefore, consumption of S. commerson in the pre and post-monsoon has no risks for human health in the Oman Sea. [ABSTRACT FROM AUTHOR]

In this study the morphological body variation in five species of Gobiid fish from the intertidal zone of the Persian Gulf and Gulf of Oman have been investigated using 18 morphometric and also three meristic characters. According to the results, 19 of 21 morphological characters of studied species showed a significant statistical difference and among these species, the only two characters "total length" and "pre anal distance" were not statistically different. The results of linear discriminant analysis (LDA) had separated 24.95% of individuals by using morphological characters of the fish body. Data analysis by principal component analysis (PCA) showed that some of morphological characters could be more determinant in species separation in two first axis (PC1 and PC2) which occasionally are possessed in common between two studied species. On the other hand, calculating the Euclidean distance according to studied morphological characters represented that there are small differences in body shape of some species i.e., Boleophthalmus dussumieri and Scartelaos tenuis among other studied species. The results of this study revealed that studying the morphological characters in gobiid fish body shape using univariate and multivariate analysis could make a new vision in these morphological variations of fish body survival. [ABSTRACT FROM AUTHOR]

In this study, the seasonal changes of plankton in the north of Oman Sea have been investigated using the three-dimensional Regional Ocean Modeling System (ROMS) model. The initial conditions of the model follow the preliminary conditions as in WOA5 data with a horizontal resolution of 0.25 degrees and a time step of 300 seconds for one year. Vertical coordinate data were for 30 layers sigma levels by interpolations in the vertical direction of temperature and salinity. Due to the greater sub-model compatibility, ROMS model is coupled with Nutrient-Phytoplankton-Zooplankton-Detritus (NPZD) model. The simulation results showed that: (1) Temperature change is one of the main factors in the frequency of phytoplankton and zooplankton blooms; (2) Clock and counterclockwise Eddies, which represent the phenomenon of extra down or upwells in the Sea of Oman and the Strait of Hormuz, causes the transfer of chlorophyll from the south to the north; (3) The amount of chlorophyll is higher during winter compared to summer. It can be due to the presence of seasonal thermocline layer which prevents blooming despite the availability of nutrients; (4) The phytoplankton cncenteration changes in a period of one year shows that their maximum value is in late March and early spring, and April is the peak of zooplankton due to the increase in phytoplankton population. Moreover, the density of plankton depends mainly on mineral nutrients, therefore, the availability of minerals is often considered as a key factor in their growth and metabolism; (5) Chlorophyll content shows a positive correlation with water surface temperature in winter (r = 0.965), while a negative one in summer (r = -0.549). There is a significant difference between chlorophyll density in winter and summer (p <0.05). There was a positive correlation between amount of chlorophyll and nitrate in winter (r = 0.268) and summer (r = 0.794), which suggests a significant difference between winter and summer (for p <0.05); (6) There were good agreements between satellite observations of temperature and chlorophyll and the values measured in numerical modeling in majority of the cases. [ABSTRACT FROM AUTHOR]

The asymptotic body size of fish species is particularly vulnerable to changes in environmental conditions, such as salinity, temperature, and food availability. One critical fisheries implication of this response is changes in yield; notably, yield reduction is expected to result from species with smaller asymptotic sizes. However, changes in asymptotic lengths are associated with changes in other vital rates as well—including growth coefficient and natural mortality—which also affect fishery yields. Here, we investigate the effects of smaller asymptotic lengths—and associated vital rates—on fisheries yield-per-recruit by comparing fish species occurring in one of the world's most extreme marine environments, the Arabian/Persian Gulf (Gulf), with their counterparts in the adjacent and more environmentally benign Oman Sea. By comparing seven species in the two areas, we find that most species occurring in the Gulf consistently attain smaller asymptotic lengths than those in Oman Sea—an outcome that is consistent with the finding that species living in environmental extremes attain smaller body sizes. While the majority of species attaining smaller asymptotic lengths occur in the Gulf, more grew faster towards their asymptotic lengths and it is expected that these fish have higher natural mortality. When examining fishery implications by setting vital rates based on area, smaller asymptotic lengths did not necessarily result in a lower yield-per-recruit, particularly in species with small differences in asymptotic sizes and higher growth coefficient and/or lower natural mortality. Our results suggest that a more nuanced evaluation of the fishery impacts of smaller asymptotic body sizes can be obtained by accounting for vital rates in addition to asymptotic fish sizes. [ABSTRACT FROM AUTHOR]

Abstract The Makran Accretionary Wedge (900 km across) is a consequence of northward subduction of the oceanic part of the Arabian Plate beneath the Lut and Afghan blocks in the northwestern Indian Ocean. It has a complicated tectonic setting as it is located at a triple junction with the Indian Plate. Thick sedimentary layers, a shallow angle of the subducting slab and a large width of the subduction zone, ca. 500–600 km from volcanic arc to active wedge front, are some of the foremost and distinctive characteristics of the Makran Subduction Zone (MSZ). The MSZ is likely divided into at least two segments: the west and the east possibly separated by a sinistral fault known as the Sonne Fault. A division is also inferred from seismicity as it is higher in the east when compared to the west. With the exception of a notable trench, all other characteristics of an accretionary prism observed in well-studied subduction zone can be identified or inferred in the Makran. Three long seismic profiles of the western Makran (200 km long each, with shot points interval of 20 km and receivers interval of 700 m) have recently been acquired. Using these datasets, improved structural/velocity models for the western Makran were developed. This review aims to contribute to achieving a better understanding of the seismotectonic setting and dynamics of the Makran Subduction Zone as it feeds to a refined understanding of the tsunami hazard in the region.

Background and Objective: Marine pollution is growing due to human activities. Continuous increase in plastic production and poor management of plastic waste resulted in a significant increase of this contaminant in aquatic environments. This in turn led to the widespread presence of Microplastics (MPs) with a size of less than 5mm. Materials and Methods: In this study, frequency, distribution, color and type of MPs in the gastrointestinal tract of fish in Oman Sea were investigated using random sampling, tissue digestion and flotation of MPs. Results: The total number of the MPs found in the studied species was variable. The highest number of MPs were found in the species belonged to Rastrelliger kanagurta and Nemipterus japonicus (29%) and Saurida tumbil, Trichiurus lepturus and Paragaleus randalli (14%). Conclusion: The forms mostly observed were belonged to microfibres (86%), fragment (11%) and pellet (3%). The most frequent colors that were detected were in a decreasing order blue, pink and black. The results demonstrated that the highest concentrations of MPs were observed in Ratrelliger kanagurta and Nemipterus japonicus species. The present study provides useful information for further research, and a background analysis to monitore the pollutants in the Oman Sea.

Seaweeds are one of the most important resources for extraction of natural bioactive components. In the present study, effect of different solvents (methanol 100%, methanol 70%, acetone 100%, and acetone 70%) was evaluated on the phenolic components extraction and antioxidant properties of two brown seaweed species (N. zanardinii and P. australis) from Chabahar coasts. Antioxidant activities of the first extract and its fractions including chloroform, dichloromethane, ethyl acetate and aqueous phase were measured using total phenolic content, DPPH free radical scavenging activity, reduction power and metal chelating activity methods. Phenol content and antioxidant properties were higher in 100% methanolic extract compared to other treatments for both algae. Ethyl acetate fraction of N. zanardinii showed the best antioxidant activities. Antioxidant properties of N. zanardinii were considerably higher than P. australis. The results showed that N. zanardinii can be considered as potential sources of natural antioxidants.

This research was carried out to assess the effect of depth on distribution pattern, on density, and Catch Per Unit Area (CPUA) of Nemipteridae family in Oman Sea. Sampling was carried out using Ferdose I investigative vessel by trawl floor in cape of meydani (55° 58) east to Govater (61°25׳) east in the waters of the Oman Sea (Sistan and Baluchistan) in September-October 2013 (during 25 days). The whole sampling area was divided into five regions (A, B, C, D, E), with depth layers of 10-20 m, 20-30 m, 30-50 m and 50-100 min a total 82 trawl stations. The highest biomass and CPUA of Nemipteridae were recorded in the stratum D (Kenarak,Chabahar, Ramine-Kijdof) approximately 1075.5 tons and 2002.8 kg/nm2, respectively. Moreover, the highest biomass and CPUA were observed in depth layer of 30-50 approximately 919.8 tons and 2641.9 kg/nm2, respectively. Finlay the distribution map of this family was drawn with Arc-GIS version 9.3 software. The results showed that the main habitat of this family is D station (Kenarak,Chabahar, Ramine-Kijdof) in depth 30-50 m that can be affected by several factors such as food abundance and environment factors.

The wave and current patterns of the Beris port and its surroundings before and after construction of the breakwater structure was investigated by numerical model, MIKE 21. For this purpose, the required data was provided and the model was prepared for implementation within a month from July 22 to August 21, 2016. In order to verify the modeling results, the extracted data were compared with the data derived from the global wave model; WAVEWATCH III and ECMWF. The simulation results show the significant effect of the breakwater on the stillness of the basin and the change in flow direction. According to the position of the port and the morphology of the coast, is expected to parallels sedimentation caused by waves and currents of the region focused on the long arm breakwaters and adjacent to the entrance mouth of breakwaters, as well as in the coastal part of the small arm of the breakwater.