جستجوی مقالات مرتبط با کلیدواژه « خلیج فارس » در نشریات گروه « علوم پایه »

The rising CO2 levels in the atmosphere are a major concern for the environment due to their potential impact on future global climate and the anthropogenic oceanic CO2 sink. Greenhouse gas emissions in the Middle East and Eastern Mediterranean regions have significantly increased since the 1950s. Oceans are crucial carbon reservoirs on Earth. Understanding the spatio-temporal variability in CO2 exchange between the atmosphere and sea, as well as its drivers, is essential for assessing ocean vulnerability and quantifying their ability to store carbon under future climate conditions. This study examines the spatial and temporal changes in sea surface CO2 (PCO2) and atmosphere-sea CO2 flux (FCO2) in the Persian Gulf, Red Sea, Caspian Sea, Arabian Sea, and Mediterranean Sea from 1982 to 2019. Additionally, the research will investigate the underlying mechanisms of seasonal PCO2  variability.

This study utilizes data from the Max Planck Institute to examine the temporal and spatial changes of air-sea CO2 exchange. The data was obtained by fitting a biogeochemistry diagnostic model of the ocean mixed layer to the ocean surface CO2 partial pressure data. Reanalysis data of temperature and wind speed was used to investigate the factors controlling the variability of FCO2 and PCO2. Additionally, the study examined the factors influencing the variability of PCO2 in each pixel, including the effects of temperature change and non-thermal components such as circulations, vertical mixing, biological changes, dissolved inorganic carbon, and upwelling systems.

CO2 flux has been estimated at up to 50 g C m-2 year-1 over the western regions of the Arabian Sea. The Red Sea is a source of CO2 in all seasons, except for the northern regions, which is a sink of CO2 in winter and spring. The intensity of the CO2 sink has increased in the Persian Gulf and the western areas of the Mediterranean Sea, and decreased in the eastern areas of the Mediterranean Sea and the Black Sea. The CO2 source intensity has decreased in most of the seas, including the Arabian Sea, the Red Sea and the central areas of the Mediterranean Sea during the studied period. Temperature is the most important driver of the seasonal cycle of PCO2 in the Mediterranean Sea, Caspian Sea, Persian Gulf and Red Sea. In addition to temperature, the non-thermal component also plays an important role in the central regions of the Red Sea and the southern regions of the Persian Gulf. The CO2 flux over the seas of West Asia follow the pattern of sea surface partial pressure of CO2. The CO2 flux has a high correlation of +0.80 with the wind speed in the western regions of the Arabian Sea, which is related to the summer monsoon. The high PCO2 (500 μatm) and FCO2 (140 g C m-2 year-1) over the northwestern Arabian Sea in the summer season are due to the monsoon driven upwelling of CO2-rich waters from the lower levels.

Significant changes were most noticeable in the western Arabian Sea. This signifies positive steps towards reducing anthropogenic CO2 emissions. This region holds great socio-economic importance for the coastal countries, with its inhabitants relying heavily on fishing for their livelihood. This underscores the immediate need for science-based management strategies to address the effects of climate change and safeguard the socio-economic well-being of coastal communities in this area.

The present study was carried out in the fishing grounds of small pelagic fish on Qeshm Island (namely Ramcha, Souza, Messen, and Salakh) from September 2022 to June 2023. Field sampling was performed by double-boat purse seiners and conducting 57 netting. The length, height, and mesh size of purse seines were 300 m, 50 m, and 10 mm (STR). Data of date, time of setting, location, and weight of target species and bycatch were recorded for each setting net. The mean CPUE (±95% CI) of small pelagic fish was overally obtained at 991.23 ± 157.14 kg per set. This was 1300 ± 364.01 for Salakh, 1246.88 ± 295 for Ramchah, 669.23 ± 214.20 for Messen, and 587.5 ± 155.71 for Souza, which there was a significant difference between Salakh and Ramcha compared to Souza and Messen (P<0.01). Also, the mean CPUE (±95% CI) of target catch for warm and temperate seasons were 1227.42 ± 224.11 and 709.62 ± 174.20 kg per setting net, which was significantly differ (P<0.01). The maximum and minimum of occurrence percentages were attributed to anchovy (with 100%) and Trichiurus lepturus (with 1.75%). The highest and lowest of mean CPUE (±95% CI) for bycatch species/groups, were related to the Trichiurus lepturus (1.75 ± 3.51) and Dasyatidae (0.07 ± 0.10) kg per setting. Given that fishing efforts have increased in recent years in the region, the estimated values of CPUE for target catch were smaller than in previous studies. Therefore, the fisheries managers must take immediate action to optimize the ongoing fishing effort.

Background and Theoretical Foundations: 

Blue economy, which has been become a principal part of political, economic and scientific diplomacy of various countries, focuses on economic growth based on sustainable exploitation and protection of marine resources. Marine aquatics production (capture fisheries and aquaculture) is one of the main sections of development of blue economy.  Iran (Islamic Republic of), with 1800 km borderline with the Persian Gulf, is the largest fisheries state in the region and has a high capacity in terms of blue economy.

A qualitative study was used to gather data through a literature review on blue economy. Forty-three scientific papers were analyzed and their primary concepts were illustrated by a word cloud graph.  

Analyses of the contents indicated that blue justice is a top ten concept to blue growth. As a consequence of overfishing and climate change, fish stocks of Iranian coastal waters of the Persian Gulf have mostly been depleted in the past few years. It has led to increasing the vulnerability of small-scale fishing (SSF) communities than before. Therefore, it should be paid a specific attention to these communities in processes of policy making to development of blue economy.

Showing the limitations of blue justice implementation in the region, the present paper demonstrated that blue economy will not developed without considering justice and its implementation is a task for government.

Due to global warming and climate changes, the water level of the Persian Gulf has increased, and these changes have led to an increase in sedimentation level and retreat of mangroves in the Hara protected area towards land. In the present study, the trend of changes in the water level of the Persian Gulf from 2000-2023 and also the extent of mangrove forests in the Hara protected area in Hormozgan province were investigated. In this study, the fluctuation trend of Persian Gulf water using L5-TM images for the year 2000 and L8 and OLI-TIRS images for the year 2023 in the Google Earth Engine (GEE) web system. It was monitored and analyzed. In this way, the water level monitoring maps of the Persian Gulf were extracted based on the normalized difference of water zones index (NDWI) and classified into two classes, blue and non-blue. In the following, using the Kolmogorov Smirnov statistical tests and Spearman's non-parametric correlation coefficient, the relationship between the water level changes in the Persian Gulf and the extent of mangroves in the Mangrove Protected Area was investigated. According to the results, the fluctuations of the water in the Persian Gulf from 2000 to 2023 had an increasing trend, so that the sea level in 2000 was equal to 5 mm and in 2023 these changes reached 90 mm. Also, the results of the extent changes of mangrove forests in the Hara protected area indicate that this habitat has decreased in 2023 compared to 2000. The analysis of the relationship between changes in the water level of the Persian Gulf and the extent of mangroves in this area reveals that a high correlation can be seen between these two variables during the studied years. This means that there is a direct relationship between the increase in water level changes in the Persian Gulf and the decrease in the mangrove forests of the Hara Protected Area. The continuous increase in sea level and its consequences can be one of the most important reasons for the reduction of mangrove habitats in the future. Considering the importance of mangrove habitats in the Hara protected area as a provider of a wide range of ecosystem services, as well as high biodiversity, management solutions should be considered to control and reduce the consequences and risks caused by the fluctuations of the sea water in the Persian Gulf.

Stock Assessment of marine aquatic is essential for modern management and sustainable conservation of fishery species, which has been rapidly developed by improving the ability of computer simulation with stock assessment methods, and for sustainable management and exploitation of fish stocks, knowledge of parameters such as age, growth and reproductive biology fishes are essential, and the output information can be used to plan and develop fisheries programs in the future. Fishing management has a wide range of goals, which include identification of aquatic population, assessment of stocks, use and development of fishing tools in order to efficiently exploit the stock and ensure the benefits of fishing users by providing a sustainable harvest deal. Stock assessment models are one of the strategies used to preserve fishery species.

In this study, some biological characteristics of greenback mullet fish were investigated during six months of 2023 in the coastal waters of Bandar Abbas. For this purpose, after sampling, 120 of the fishes caught were transferred to the laboratory for biometry of length and weight parameters and were subjected to biometrics. After morphometric analysis of greenback mullet samples, fish growth parameters such as Growth performance index, condition index, von Bertalaneffy growth function (VBGF), mortality coefficients and exploitation ratio were calculated using FiSAT software processing.

The results of the study showed that the average total length and weight of greenback mullet fish were 11.06 cm and 21.90 gr, respectively. In this fish, the relationship between total length and total weight was obtained as W=0.1886TL1.9226. The parameter of condition index in the entire sampling period had strong fluctuations in the first half of the sampling period and did not change significantly in the second half and was almost the same. Among the parameters calculated, we can mention the growth function of von Bertalaneffy growth function and factors such as forked length, growth coefficient and t0 were calculated as 20 cm, 1.1 and -0.1 per year, respectively. Total and natural mortality rates were estimated as 2.56 and 2.07 per year for the samples, respectively.

Stock assessment is the process of collecting, analyzing and reporting fish population information to determine changes in the abundance of fishery stocks in response to fishing and to predict the future trends of stock abundance as much as possible. In this study, the results showed that greenback mullet fish in the coastal waters of Bandar Abbas are young fish. For both males and females, the growth index is the highest, and overfishing, especially during the spawning seasons, has messed up the regeneration of the young population, Therefore, not having proper management in fishing can damage this valuable stock in the coastal waters of Bandar Abbas. Therefore, it is suggested that this study be re-evaluated in a longer period of time and with a larger number of samples so that the results can be proven with more certainty.

The present study was conducted with the aim of investigating variations of diet of copepods in the Strait of Hormuz in both cold and warm seasons using fatty acid profiles with considering the effect of dominant phytoplankton groups in the region. The studied stations were selected as a transect perpendicular to the Bandar Abbas coast and in the center of the Strait of Hormuz. Four stations were sampled in this transect. Sampling was done in two hot seasons (July) and cold season (January). A vertical plankton net with an opening of 50 cm, a length of 2 m, and mesh size of 300 μm in the body part and 100 μm in the collecting container (Netbucket) was connected to a winch from the upper part and a 5 kg weight from the end part. Sampling was done from a depth of 10 meters to the water surface as a vertical pull between 9:00 and 15:00. This operation was repeated three times in each station. The first and second replications were fixed using 4% formalin and transferred to 500 ml containers, and the third repetition was placed in a -40°C freezer located on the research vessel and transferred frozen to the laboratory. The first and second replicates were used to identify and enumerate copepods, and the third replicate was used to isolate and prepare fatty acid profiles. To measure environmental parameters, water samples of each layer (5 meters and 15 meters) were transferred to the floating surface using a Niskin bottle, and parameters were measured using a Hach multimeter. In order to identify phytoplankton groups, one liter of water was taken from the water surface at the sampling point and poured into dark containers and fixed with acidic Lugol solution and stored in cool conditions at room temperature (below 25°C).To concentrate phytoplankton cells, the method of sedimentation process was repeated twice. In this method, the water sample was transferred to a one-liter graduated cylinder and after 72 hours, 90% of the surface water was decanted. Then, the remaining sample volume was transferred to a 100 ml graduated cylinder and again after 72 hours, 90% of the surface water was decanted. After that, to remove the concentrated sample, the container was stirred to mix well, then using a pipette, one milliliter of the sample was transferred to the Sedwig Rafter counting slide. Samples were analyzed using a Nikon inverted microscope with 400x magnification. Finally, the number of cells of each phytoplankton group per milliliter was calculated.Zooplankton samples were separated from the fixative solution using a 100-micron sieve. Then the samples were transferred to 70% alcohol and glycerin solution. After that, the copepod samples were separated from other zooplankton using a Leica stereomicroscope. Finally, different copepod species were identified at the genus level. Using numbers recorded by the flowmeter, the volumes of water filtered by the plankton net was calculated for each net haul. Finally, the density of copepods was calculated as number per cubic meter. The separation of copepods from frozen zooplankton samples was done quickly and under conditions of near zero temperature. Then the isolated copeod samples were frozen again. Finally, the samples were transferred to the central laboratory of the National Research Institute of Oceanography and Atmospheric Sciences in frozen form for analyzing fatty acids content.Cyanobacteria with 52% relative abundance were the dominant group in July. All the cyanobacteria observed in this study were Trichodesmium erythraeum, and after those, diatoms and dinoflagellates formed 36 and 12% of the phytoplankton groups in July, respectively. In January, diatoms were the most abundant phytoplankton group (74%) and cyanobacteria were rarely found (1%). A total of 17 genera of copepods were identified. Acartia sp. (30.57 %) and Oithona sp. (19.03 percent) the most abundant copepods were in July. In January, Calanopia sp. (16.2 percent) and Oncaea sp. (15.26%) were the most abundant copepods. The feeding type of copepods changes according to the season and available prey. In this study the majority of observed copepods were herbivores and omnivores.In July and January, hexadecanoic fatty acid has the largest share of the identified fatty acids in the total of fatty acids with 32 and 27%, respectively. The cis-Vaccenic index fatty acid also accounted for 9 and 4% of the total identified fatty acids in July and January. Docosahexaenoic fatty acid (DHA) with 4% in July and eicosapentaenoic fatty acid (EPA) with 2% abundance were found in January samples. In July, 4% of DHA was found in the total amount of fatty acids, which indicates the consumption of flagellates by copepods. Higher abundance of flagellates in July and abundance of Oithona sp. which prefer the consumption of flagellates caused Higher DHA percentage in summer samples. In January, EPA constituted 2% of the total amount of fatty acids, which indicates the consumption of diatoms by copepods in winter.The results of this study showed that the zooplankton community structure is significantly different between the cold and warm seasons in the Strait of Hormuz. Dominant phytoplankton groups also change significantly in the Strait of Hormuz in both cold and warm seasons, and the effect of changes in the community of primary producers in the Strait of Hormoz can be observed by tracking fatty acid markers in secondary producers. The environmental conditions in summer and winter are significantly different in the Strait of Hormuz. Water temperature and salinity were higher in July and the amount of dissolved oxygen measured in January was lower. However, we cannot obtain detailed information about the nutritional relationship of copepods and phytoplankton groups with the results of this study, but we can increase our general knowledge about their nutritional relationships in the Strait of Hormuz. Obviously, the amount of production in summer was higher than in winter. But the composition of prey available to primary consumers (herbivorous copepods) has changed. In this way, in summer, cyanobacterial flagellates were more available than diatoms. The question is, do copepods directly consume cyanobacteria and lead to continuation of the bacterial production in the food chain? By comparing the relative frequency of cis-Vaccenic acid as an indicator of bacteria in winter and summer, it can be said that the production by bacteria is transferred to the primary consumers, but the direct consumption of cyanobacteria by copepods cannot be commented. Whereas, harpactoid species known as direct consumers of cyanobacteria were not observed in this study. Regarding flagellates and diatoms, it can be said that the flagellates in summer and diatoms in winter has a greater contribution to the diet of copepods in the Strait of Hormuz.

One of the most important carbonate gas reservoirs in the Zagros and Persian Gulf sedimentary basins is the Dalan Formation. This research investigates the microfacies, lithostratigraphy, and sequences of carbonate-evaporite deposits in the Lower member of the Dalan and the Nar member belonging to the Guadalupian series with a total thickness of 2402 meters in four wells namely A, D, E, and G located in the eastern part of the Qatar-Persian arc in the Persian Gulf. The study of 340 thin sections prepared from the drilling cutting pieces with 2-meter intervals of well E, and a review of documents related to other wells led to the identification of 20 species belonging to 14 genera of foraminifera and the foraminiferal assemblages consisting of 65 species belonging to 25 genera. A foraminiferal biozone was recognized in well E, assigned to the Wordian? - Capitanian: Pachyphloia- Globivalvulina- Hemigordius, Assemblage Zone.  Additionally, 11 microfacies were determined, mainly distributed in five environments (sabkha, intertidal, lagoon, shoal, and shallow marine). Based on the stacking patterns facies and the gamma-ray log trends, two 3rd-order transgressive–regressive (T-R) sequences were determined. These sequences correspond to the sequences of the reservoir unit’s equivalent formations in the southern and eastern Tethyan basin including Saudi Arabia, UAE, Oman, Iraq and South China.

The study of food composition and feeding ecology of fishes living in the intertidal zone are essential in understanding the energetic connectivity between terrestrial and aquatic ecosystems. The mudskipper Periophthalmus waltoni is an amphibious fish in the intertidal zone. The aim of this research was to discern how spatial and temporal factors influence the species' diet. A total of 319 individuals were collected across two estuaries in Hormozgan province (184 in Bandar Abbas and 135 in Bandar Khamir) during November 2018 to April 2018. The results revealed that P. waltoni primarily follows a carnivorous diet, as indicated by their relative gut length (RLG) and diet composition. The individuals measured 9.2–11.8 cm in total length and 8.1–15.8 g in weight. Analysis of stomach contents identified three main preys: Uca, Gastropoda, and Coleoptera, with Bandar Abbas and Bandar Khamir showing a prevalence of crab (79.31%) and Gastropod (54.16%), respectively. The mudskipper's feeding strategy, as per Castello, appeared general in Bandar Abbas and specific in Bandar Khamir. The highest frequency index of prey occurrence for specimens in Bandar Abbas for crab prey was calculated at 68.31%, while in Bandar Khamir, it was determined as 42.52% for gastropods. Stomach emptiness index values of 21.49% and 13.86% suggest P. waltoni is a voracious feeder.

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

The study delved into bacteriocins, peptides with antibacterial properties, originating from select lactic acid bacteria. Isolating 18 such bacteria from Liza klunzingeri's intestine, their potential in bacteriocin production against food pathogens was assessed. Crude bacteriocins from 7 isolates exhibited the ability to inhibit food pathogens via an agar spot test. Notably, bacteriocins derived from LK5 and LK12 isolates displayed a broader inhibitory spectrum against the pathogens under study. Further analysis revealed that the studied bacteriocins were susceptible to proteolytic enzymes, leading to complete degradation. However, these bacteriocins retained their antibacterial potency when subjected to diverse detergents, pH variations, and temperature fluctuations. Genetic analysis via the 16S rRNA gene identified LK5 and LK12 as strains of Lactobacillus plantarum, with similarity percentages of 98.55% and 99.46%, respectively. The findings highlight L. Klunzingeri's intestinal bacterial flora as a promising source for isolating bacteriocin-producing bacteria. Specifically, bacteriocins derived from L. Plantarum LK5 and L. Plantarum LK12 showcase potential as biological preservatives within the food industry, warranting further exploration.

The study aimed to assess temporal and spatial variations in the population of polychaetes, a significant invertebrate group in deep-sea ecosystems, across the northern waters of the Persian Gulf and the Oman Sea. Sampling occurred from fall 2018 to winter 2020, covering regions in Hormozgan, Bushehr, Sistan and Baluchestan, and Khuzestan. A total of 115 stations were surveyed, utilizing 0.1 square meters and a 500 μm sieve (repeated thrice) to collect bed sediments within the depth range of 12 to 90 meters. Within this study, 35 species/genus of polychaetes were identified in the waters of the Persian Gulf and the Oman Sea. Notably, Flabelligra sp., Manayunkia aestuarina, and Glycinde sp. exhibited the highest abundance, with Flabelligra sp. and M. aestuarina serving as indicator species in both regions. The provinces of Sistan and Baluchestan and Bushehr displayed the highest Shannon diversity and species richness, recording 3.592 and 6.998, respectively. Comparing these findings with prior reports revealed a reduction in the diversity of identified polychaete species in the Persian Gulf. This decline could stem from various factors such as habitat damage due to fishing equipment, and the incidence of contaminants. Continual research and database establishment for time series analysis could significantly aid researchers, authorities, and environmental advocates in comprehending the health status of the Persian Gulf and the Oman Sea. Such efforts would facilitate environmental monitoring and pollution prevention measures, contributing to the preservation of these ecosystems

In this study, 286 samples of Matuta planipes crabs (Fabricius, 1798), including 136 male crabs and 150 female crabs in the coastal waters of the Persian Gulf (Hormozgan province), were collected monthly from July 2018 to May 2019 and It was recorded biometric data and some aspects of its reproduction were studied. The results showed that the annual male: female sex ratio of this species is not 1:1 and female crabs were more dominant with 52.3%. Also, the sex ratio of male: female crabs in different carapace width classes had significant differences. All stages of ovarian maturation were observed throughout the year. The abundance of egg-bearing crabs (stage 5 of ovarian maturity) in all months of the year indicates that this species is capable of continuous spawning year around, but according to the abundance of female crabs in stage 4 of maturation, as well as the gonadosomatic index, the peak of spawning for this species, in the region is from end of winter to spring. The homogeneity rate of egg-bearing females showed that in this species, each female with a carapace width between 22-50 mm can produce 5972-357110 eggs. The average number in this study was estimated to be 87996 eggs. The results also showed that the minimum size of this species that reaches sexual maturity is 33 mm in carapace width and the length at which 50% of female crabs reach sexual maturity is estimated to be 37 mm in carapace width. Given the recorded results of this study, the ovigerous females are seen throughout the year and the monthly changes of gonadosmatic index in the female indicate that spawning peak ocured in the spring.

Coral reefs are one of the most important and diverse marine ecosystems that provide many benefits to humans. The increase in the sea surface temperature (SST), leads to their biology disruption and bleaching. In the present study, the relationship between the increase in SST due to climate change and the interactions between genes and proteins has been investigated. The results can give us a perspective on the extent of the vulnerability of corals to stress and the adoption of methods to protect them. Data on SST anomalies in the Persian Gulf was obtained using satellite data. The metabolic pathway of sod and cat genes in oxidative stress, and hsp90 gene in heat shock pathways were obtained by KEGG. Gene and protein interactions were obtained through GeneMANIA and STRING databases respectively. SST analyzes showed that there are temperature fluctuations in the Persian Gulf from the lowest temperature, about 16 °C to about 35 °C in Khark Island. Therefore, the coral reefs of the Persian Gulf tolerate very high temperatures. During thermal stress, the coral host responds to oxidative stress by regulating the expression of antioxidant genes, including sod and cat, to protect the coral-algae symbiosis. In addition, the expression of hsp90 indicates its role in protecting proteins from heat damage. Understanding the relationship between SST and the molecular health status of coral reefs is essential to develop conservation strategies to protect these marine ecosystems in the face of climate change.

The Kazhdumi Formation (Albian) consists of shale to limestone and marl facies, considered as one of the most important source rocks in the north of the Arabian Plate. This study evaluates the geochemistry of the Kazhdumi Formation as a potential source rock in the northwest of the Persian Gulf in the Hendijan, Soroosh, Foroozan, and Kharg fields. For this purpose, Rock-Eval pyrolysis analysis was performed on 140 cutting samples to assess the quantity and quality of organic matter and 53 vitrinite reflectance samples to examine the maturity. The absence of stratification in the water column and unsuitable environmental conditions have not led to the proper preservation of organic matter. Therefore, organic matters are mostly influenced by continental type kerogen (Type III) in this study, ranging from immature to early mature kerogen based on vitrinite reflectance.. However, towards the northeast sector of the Arabian Plate (Hendijan and Kharg fields), due to the presence of organism growth conditions in the water column and the prevailing anoxic conditions at the water-sediment contact (intra-shelf basin), the preservation of organic materials has occurred. The organic matter in this section is mostly marine type (Type II kerogen) and mature based on the vitrinite reflectance data. It seems that the Khafji-Hendijan paleo-high has played an important role in the maturity of the Kazhdumi Formation due to its influence on sediments after the deposition of the Kazhdumi Formation.

One of the most important secondary metabolites of the marine sponges are steroids. The aim of this study is to investigate the antifungal activity of the steroidal fractions derived from the sponge Axinella sinoxea from the waters around Lark Island in the Persian Gulf. Extraction from sponges was done with acetone and separation of fractions was done by column chromatography with silica gel using a range of solvents with different polarity. Identification of steroidal fractions were done by thin layer chromatography and gas chromatography coupled with mass spectrometry. Then, antifungal properties of the steroids were investigated through determining the minimum inhibition concentration and minimum fungicidal concentration by tubular dilution method against Aspergillus fumigatus and Candida albicans. The identified steroids included compounds of Stigmasta, Ergosta, Cholest and Norgorgosta, which showed different results regarding the growth inhibition and killing of fungi and yeast strains at different experimental doses. Stigmasta and Ergosta showed more antifungal effects against A. fumigatus compared with the other steroids and Ergosta caused the best inhibitory and killing effects against C. albicans compared with the other steroids. In conclusion, promising results were found regarding the antifungal effects of the extracted steroids of the marine sponge A. sinoxea, revealing the necessity of more comprehensive investigations for the synthesis of biomedicines from the marine bioactive compounds.

The Persian Gulf and the Oman Sea are habitats for a variety of aquatic species, especially fish. Heavy metals are crucial pollutants in aquatic ecosystems and can be among the major factors influencing the health of consumers. The purpose of this essay is to conduct a systematic review of studies that have assessed the concentration of heavy metals in the muscle tissue of certain fish species in these waters, spanning from the year 2006 to 2018. This meta-analysis study was performed on 1182 muscle tissues of Pampus argenteus, Platycephalus indicus, Lutjanus johnii, javelin grunter, Johnius belangerii, Otolithes ruber, Scomberomorus commerson, Scomberomorus guttatus, Epinephelus coioides, caught from the Persian Gulf and the Oman Sea, in order to investigate the amount of these metals. Also, the safety of food intake and the comparison with the standards were investigated. The THQ and HI indices were found to be less than 1 in the all species of fish for adults, but for children only in Scomberomorus commerson in HI index is more than one. The amount of mercury, zinc and lead in the all pecies of fish, cadmium in Lutjanus johnii and javelin grunter and nickel in Scomberomorus guttatus and Epinephelus coioides were lower than all standards. The daily and weekly absorption rates for all studied metals were lower than the authorized JECFA Committee due to fish consumption. Also, the lowest amount of allowance for studied metals was found mercury in Scomberomorus commerson, lead in Johnius belangerii and cadmium in Platycephalus indicus. It seems that high use of the Platycephalus indicus in terms of the studied metals has led to health risks in children. Therefore, environmental protection, which it has been influential in creating nutritional health problems, is considered a necessity.

The Mediterranean-Arab (Arab-Med) Corridor of India to Europe is an emerging multi-faceted trade corridor that could fundamentally alter trade patterns between the Indian Ocean region, the Middle East, and Europe by creating a crescent of trade connectivity on the southern edge of Eurasia from the coasts. The Arabian Sea of India will change to the eastern Mediterranean coast of Greece. For India, this new corridor is a strategic paradigm shift with huge geopolitical implications that could change its role in the Eurasian economic order. Based on this, the current research, which was carried out in a descriptive-analytical way, seeks to answer the question of what effect does the Arab-fashion corridor have on the new architecture in the trans-regional connection? The hypothesis of this research is that the Arab-Med Corridor is creating an alternative trans-regional trade architecture in which the UAE ports can act as the connecting point of the Indian Ocean to create a separate trade corridor from India to Europe and India to The title introduces a new power to the world with the ability to create transregional commercial architecture. The establishment of a Mediterranean terminal - from Haifa to the European mainland at the Greek port of Piraeus - means that Indian goods sent to UAE ports can reach the main markets and production centers of Europe.

The Persian Gulf hosts a variety of marine ecosystems, including mangrove forests, seagrass beds, and coral reefs, which have adapted to the challenging environmental conditions of the region to some extent. These ecosystems are increasingly influenced by rapid population growth, economic development in the countries surrounding the Persian Gulf, as well as, the impact of climate change in the region. They are facing mounting pressure from human activities. The influx of nutrients, coupled with the warming of the Persian Gulf, can result in a reduction in the dissolved oxygen concentration in the water. Consequently, the simultaneous occurrence of warming, reduced oxygen, and acidification in the Persian Gulf has become a significant challenge for its valuable ecosystems. According to studies, hypoxic areas in the Persian Gulf in mid-autumn can extend to more than 50,000 square kilometers. The occurrence of hypoxia in the Persian Gulf during late summer is confined to two primary areas in the western and central regions. In the eastern Strait of Hormuz, hypoxic conditions are observed in the near-bottom layer from early summer to mid-winter in areas distant from the Gulf's outflow. The reconstruction of dissolved oxygen concentrations in recent decades also indicates a declining trend accompanied by an increase in the extent and duration of hypoxia in the Persian Gulf. The degradation of water quality in the Persian Gulf, in addition to its adverse effects on its valuable ecosystems and consequently on fisheries and aquaculture in the Gulf, can significantly impact the Gulf of Oman and even the Arabian Sea in various ways, exacerbating the conditions of Oxygen Minimum Zones (OMZ) in these expansive seas. The Gulf of Oman and the Arabian Sea naturally and permanently host the widest and thickest OMZ in the world ocean. Depths exceeding 400 meters in the Gulf of Oman exhibit suboxic conditions (oxygen concentration less than 6 µmol/kg) during both summer and winter. The OMZ in the Arabian Sea and the Gulf of Oman has intensified over the past few decades. Oxygen levels recorded in 1960 in the core of the OMZ in the Arabian Sea and the Gulf of Oman ranged from 6 to 12 µmol/kg but have now dropped to levels below 6 µmol/kg (suboxic). This intensification of the OMZ in the Arabian Sea and the Gulf of Oman has adverse effects on the ecosystems of this region and the livelihoods of dependent populations. Marine organisms residing in the near-bottom layer or surface sediments are most affected by the expansion and intensification of hypoxic and suboxic conditions. Oxygen deficiency leads to a decline in the biodiversity of benthic communities, promoting resilient species such as polychaeta in surface sediments. The reduction in oxygen levels in the Arabian Sea has significantly influenced the composition of phytoplankton communities, the vertical migration of zooplankton, and myctophidae in the water column. The expansion and intensification of the OMZ, with its adverse impacts on fishing and aquaculture, also carry socio-economic implications for residents of the coastal areas of the Indian Ocean, the Gulf of Oman, and the Arabian Sea. Considering the prevalence of seasonal hypoxic conditions in the Persian Gulf and permanent suboxic conditions in the Gulf of Oman, addressing this trend and mitigating its environmental and economic impacts in the region is crucial. Management and policy strategies to halt or reduce the effects of oxygen depletion in the Persian Gulf and the Gulf of Oman can be classified into three main categories: a) ecosystem-based mitigation measures for environmental restoration and protection, b) adaptation-based measures to restore and protect marine organisms and fisheries, c) implementation and maintenance of monitoring programs and analysis of the information obtained. In essence, efforts to integrate research, management, and policy actions in oceans and seas across all biological, geochemical, and physical disciplines, addressing all climate change-related issues such as warming, acidification, and oxygen reduction, and involving all academic, industrial, governmental, and regulatory sectors, constitute the most effective roadmap recommended for combating the impacts of climate change on marine resources.