Oman Sea Research Articles

Interpretation of Water Samples by Correspondence Analysis for Radioactive Elements in the Northern Coast of Oman Sea

Oman Sea is connecting belt between the Indian Ocean and PersianGulf. Because it strategic and environmental aim, presence of naturalradionuclide 226Ra, 232Th, 40K and 137Cs as man-made element is considered.Water samples were taken from 36 marine spots at the coastal strip fromHormoz canyon to Goatr seaport in the northern coast of Oman Sea.Correspondence analysis is used to identify variation and relationshipbetween samples (Q-mood analysis) and variable (R-mood analysis) basedon approximate χ2 distances. Radioactive elements (226Ra, 232Th and 40K),physical (temperature, pH, turbidity, conductivity, special density) andchemical (salinity, oxygen and chlorophyll) parameters of water for 36samples handled by correspondence analysis, there are two outstandingresult, 1) Radioactive elements show high correlation in factors by greatereigenvalue, and 2) some of the samples such as W13, W24 and rather W02,W05 and W12 show highest activity from Radioactive elements and alsotemperature and conductivity show nearest relation with them in manyfactors.

Effects of short-term exposure to the heavy metal, nickel chloride (Nicl2) on gill histology and osmoregulation components of the gray mullet, Mugil cephalus

The gray mullet, Mugil cephalus is an inshore and bottom-feeding fish species of Oman sea. Therefore, the gray mullet may be more exposed to heavy metal contamination, as the toxic impacts of heavy metals mullet has been reported in various studies. This study was conducted to evaluate the toxic effects of the heavy metal, nickel (as NiCl2) on osmoregulation of the gray mullet by measuring blood biochemicals, hormones, minerals and gill histology. Fish (10 fish/tank) were experimentally exposed to NiCl2 at three environmentally relevant concentrations of 5, 10 and 15 μg/l for 96 h. Then, fish were challenged with seawater (35 mg/l) for a period of 120 min. The samples (blood and gill tissue) were collected After 96 exposure to NiCl2 and during salinity challenge (30, 60 and 120 min post challenge). The plasma levels of cortisol and glucose significantly increased in NiCl2−exposed fish. In addition, cortisol increased in all experimental groups 30 min after salinity challenge and then returned gradually to the same levels as the control at 120 min post salinity challenge (PSC). The triiodothyronine (T3) and thyroxine (T4) levels significantly decreased in response to 10 and 15 μg/l NiCl2. In all groups, the thyroid hormones significantly elevated at 30 min PSC. After 30 min PSC, T3 levels in all NiCl2−exposed fish and T4 in the treatment, 10 μg/l NiCl2 remained unchanged throughout the salinity challenge. In the treatment, 5 μg/l NiCl2, T4 levels were recovered at 120 min PSC and reached the same levels as the control. Exposure of fish to high concentrations of NiCl2 and salinity stress increased the lactate levels. However, lactate levels in 5 and 10 μg/l NiCl2 groups were recovered at 120 min PSC and reached the same levels as the control. Furthermore, plasma protein increased in response to 10 and 15 μg/l NiCl2. At 30 PSC, the protein levels decreased in control and 5 μg/l NiCl2 group, while it remained unchanged in fish exposed to 10 and 15 μg/l NiCl2 throughout the salinity challenge. Exposure of fish to NiCl2 disrupted the electrolyte (Na+, Cl−) balance both before and after salinity challenge, which may be due to gill lesions induced by the heavy metal and following alternations in gill permeability. However, fish in 5 μg/l NiCl2 re-established the ionic balance in the blood at the end of salinity challenge period. The malondialdehyde (MDA) levels significantly increased in response to 10 and 15 μg/l NiCl2. The MDA levels returned to the same levels as the control group at 120 min PSC. The results of the present study showed that nickel-induced toxicity (especially at high concentrations) can reduce the osmoregulation capabilities of mullet. However, fish are able to recover from the toxic effects over time, if contamination be eliminated.

Investigation of Sardinella Sindensis (Day, 1878) Stock Status Using the Catch-Maximum Sustainable Yield Model in the Southern Waters of Iran (Persian Gulf and Oman Sea)

Investigation of Sardinella Sindensis (Day, 1878) Stock Status Using the Catch-Maximum Sustainable Yield Model in the Southern Waters of Iran (Persian Gulf and Oman Sea)

Diversity, distribution and temporal variation in abundance and biomass of sea cucumber population in Pozm Bay, north of Oman Sea, Iran

The ecosystem of Pozm Bay, north of Oman Sea, Iran, is one of the unique marine habitats for benthic aquatic species. Therefore, this study investigated the distribution, diversity and temporal variation in abundance and biomass of sea cucumber species in Pozm Bay. Five transects, each of them in four triplicates and perpendicular to the sea were sampled at 3, 6, 9 and 12 m depths and three seasons (winter, spring and autumn). Different spicule patterns were chosen as identification key for each studied species. A total of five species from two families of sea cucumbers were identified in the study area, in which 191 and 41/km 2 were belonged to Holothuridae and Stichopodidae with three and one species, respectively. H. leucospilota, was found to be a dominant species in Pozm Bay and had the biggest body size and biomass in winter. The most density of sea cucumbers was recorded in winter at 48.36 g/m2, while the lowest biomass was calculated at 18.02 g/m2. H. leucospilota, H. arenicola, H. atra and S. variegatus were abundant at transects 3, 1, 3 and 1, respectively. The highest and lowest density of sea cucumbers in winter were observed at transects 1 and 2, respectively. In addition, in spring, the highest and lowest density of sea cucumbers were recorded at transects 3 and 2, respectively. Shannon and Margalof ecological indices showed that all species were common in different seasons and had a contagious dispersion pattern. Moreover, it appeared that the distribution of sea cucumbers was affected by habitat complexity in the study area. Together, findings showed that the study of distribution patterns, diversity and temporal variation of sea cucumbers can deepen our knowledge about the abundance and biomass of these valuable species, which is useful in managing the fisheries resources and protective programs in Pozm Bay.

The potential application of sea cucumber (Holothuria leucospilota) as a bioindicator of heavy metals contamination: a case study from Chabahar Bay, Oman Sea, Iran

The potential application of sea cucumber (Holothuria leucospilota) as a bioindicator of heavy metals contamination: a case study from Chabahar Bay, Oman Sea, Iran

Scales and otoliths as identity cards of the Indian oil sardine Sardinella longiceps (Teleostei: Clupeiformes) populations: Ultrastructure and ornamentation characteristics using light and scanning electron microscopy

AbstractScale 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.

A comparative study on the accumulation of toxic heavy metals in fish of the Oman Sea: effects of fish size, spatial distribution and trophic level

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.

Increased Shamal winds and dust activity over the Arabian Peninsula during the COVID-19 lockdown period in 2020.

While anthropogenic pollutants have decreased during the lockdown imposed as an effort to contain the spread of the Coronavirus disease 2019 (COVID-19), changes in particulate matter (PM) do not necessarily exhibit the same tendency. This is the case for the eastern Arabian Peninsula, where in March–June 2020, and with respect to the same period in 2016–2019, a 30 % increase in PM concentration is observed. A stronger than normal nocturnal low-level jet and subtropical jet over parts of Saudi Arabia, in response to anomalous convection over the tropical Indian Ocean, promoted enhanced and more frequent episodes of Shamal winds over the Arabian Peninsula. Increased surface winds associated with the downward mixing of momentum to the surface fostered, in turn, dust lifting and increased PM concentrations. The stronger low-level winds also favoured long-range transport of aerosols, changing the PM values downstream. The competing effects of reduced anthropogenic and increased dust concentrations leave a small positive signal (<5 W m−2) in the net surface radiation flux (Rnet), with the former dominating during daytime and the latter at night. However, in parts of the Arabian Gulf, Sea of Oman and Iran Rnet increased by >20 W m−2 with respect to the baseline period, owing to a clearer environment and weaker winds. It is concluded that a reduction in anthropogenic emissions due to the lockdown does not necessarily go hand in hand with lower particulate matter concentrations. Therefore, emissions reduction strategies need to account for feedback effects in order to reach the planned long-term outcomes.

Echinoderm Diversity in the Arabian Sea and the Sea of Oman

Echinoderm Diversity in the Arabian Sea and the Sea of Oman

Prediction of Solar Irradiance over the Arabian Peninsula: Satellite Data, Radiative Transfer Model, and Machine Learning Integration Approach

Data from a moderate resolution imaging spectroradiometer instrument onboard the Terra satellite along with a radiative transfer model and a machine learning technique were integrated to predict direct solar irradiance on a horizontal surface over the Arabian Peninsula (AP). In preparation for building appropriate residual network (ResNet) prediction models, we conducted some exploratory data analysis (EDA) and came to some conclusions. We noted that aerosols in the atmosphere correlate with solar irradiance in the eastern region of the AP, especially near the coastlines of the Arabian Gulf and the Sea of Oman. We also found low solar irradiance during March 2016 and March 2017 in the central (~20% less) and eastern regions (~15% less) of the AP, which could be attributed to the high frequency of dust events during those months. Compared to other locations in the AP, high solar irradiance was recorded in the Rub Al Khali desert during winter and spring. The effect of major dust outbreaks over the AP during March 2009 and March 2012 was also noted. The EDA indicated a correlation between high aerosol loading and a decrease in solar irradiance. The analysis showed that the Rub Al Khali desert is one of the best locations in the AP to harvest solar radiation. The analysis also showed the ResNet prediction model achieves high test accuracy scores, indicated by a mean absolute error of ~0.02, a mean squared error of ~0.005, and an R2 of 0.99.

Estimation of Groundwater Depletion in Iran’s Catchments Using Well Data

Iran is experiencing significant water challenges that have now turned water security into a national priority. By estimating secular trend groundwater storage in Iran between 2002 and 2017, we see that there is an intensive negative trend, even −4400 Mm3 in some areas. These estimations show shifting in the climate and extra extraction from aquifers for agricultural use in some areas in Iran. The secular trend of groundwater storage changes across the whole of Iran inferred from observation well data is −20.08 GT/yr. The secular trends of GWS changes based on observation well data are: −11.55 GT/yr for the Central Plateau basin, −3.60 GT/yr for the Caspian Sea basin, −3.0 GT/yr for the Persian Gulf and Oman Sea basin, −0.53 GT/yr for the Urmieh Lake basin, −0.57 GT/yr for the Eastern Boundary basin, and −0.83 GT/yr for the Gharaghom basin. The most depleted sub-basin (Kavir Markazi) has secular trends of GWS changes of −4.503 GT/yr. This study suggests that groundwater depletion is the largest single contributor to the observed negative trend of groundwater storage changes in Iran, the majority of which occurred after the drought in 2007. The groundwater loss that has been accrued during the study period is particularly alarming for Iran, which is already facing severe water scarcity.

The study of a severe dust storm over Persian Gulf, the Gulf of Oman and parts of the Indian Ocean with two operational dust forecasting models

Introduction: The entry of dust particles into water areas, which has increased sharply in recent years, causes a lot of environmental damage. The Persian Gulf and the Gulf of Oman are among the water areas that are covered with dust many times of the year. Materials and methods: In this study, a severe dust from July 27 to 31, 2018 is analyzed, in which a large part of the Persian Gulf, Oman Sea and the western part of the Indian Ocean was involved. To study this phenomenon from different perspectives, satellite products, visibility from synoptic stations and synoptic maps were analyzed and the output of two numerical dust models of NASA-GEOS and DREAM8-MACC were examined. To qualitative and quantitative evaluate of the model outputs, the Aerosol Optical Depth (AOD) of TERRA/MODIS was used. Results: Satellite imagery shows that in this case study, parts of the Persian Gulf and the Sea of Oman were affected by dust, and on July 30, dust particles entered the western half of the Indian Ocean. Comparison of model outputs with satellite data resulted that both models underestimate the AOD values, especially over water, and do not show well the entrance of dust particles into the eastern part of the Persian Gulf, the Gulf of Oman and the western half of the Indian Ocean. Conclusion: Qualitative and quantitative comparison of AOD output of the two models with satellite data showed that the NASA-GEOS model had better performance and its output correlation with observational data was higher.

Short term temporal variation of mangrove fish assemblage in Chabahar Bay (Oman Sea)

This study aimed to assess the temporal variation in fish assemblage in Chabahar Bay mangrove habitat. Baited Remote Underwater Video (BRUV) sampling method was applied to record the fish presence. Fishes were sampled monthly from June 2017 to April 2018 at daylight time (9:00 to 14:00) during high tide. Water temperature, turbidity, and salinity were recorded at the time of sampling. During the study, a total of 17 species belonging to 12 families were identified. A mbassis gymnocephalus was found as the dominant fish throughout the year except in November and December. The most abundant fish fauna in numbers was characterized by the following five species: Ambassis gymnocephalus (53.38%), Sardinella sp. (17.13%), Terapon jarbua (4.79%), Rhabdosargus sarba (3.25%) and Acanthopagrus berda (2.9%). ANOSIM showed that significant differences in the assemblage structure occurred among months (R=0.613, P < 0.001), and the CLUSTER analysis, together with the SIMPROF test showed that December is significantly different in term of fish assemblage. Canonical Correspondence Analysis (CCA) on species-environment correlations revealed that temperature and turbidity were the main parameters influencing fish occurrence in the mangrove habitat of Chabahar Bay. The overall diversity (Shannon–Wiener, Simpson’s Index of Diversity, and Pielou’s evenness), as well as functional diversity indexes (FRic and FDis), was higher in autumn and spring pointing out that the diversity is higher when the temperature had the closest value to averaged value.

Risk assessment of trace element accumulation in two species of edible commercial fish Scomberoides commersonnianus and Cynoglossus arel from the northern waters of the Oman Sea

Concentrations of heavy metals, namely, cadmium, copper, zinc, lead, and chromium were measured in the muscle tissue of Scomberoides commersonnianus and Cynoglossus arel from the northern waters of the Oman Sea. Human health risk assessment for Iranian child and adult consumers were also evaluated. The mean concentration of zinc and copper were lower than international standards of maximum permissible limits (MPL). The estimated daily and weekly intakes (EDI and EWI) of all metals were lower than permissible tolerable daily intake (PTDI). The permissible frequency of fish consumption (CRmm) of S. commersonnianus and C. arel showed that they are safe for both children and adults even at a high meal frequency (>16 meals/month). Target hazard quotient (THQ) and risk index (HI) values were higher than 1 for Cu in adults, Cu and Zn in children with consumption rate of 7 times per week. Therefore, consumption of these spices of Oman Sea more than 7 times per week can threaten the health of consumers.

Oceanic Response to Tropical Cyclone Gonu (2007) in the Gulf of Oman and the Northern Arabian Sea: Estimating Depth of the Mixed Layer Using Satellite SST and Climatological Data

The category 5-equivalent tropical Cyclone Gonu (2007) was the strongest cyclone to enter the northern Arabian Sea and Gulf of Oman. The impact of this cyclone on the sea surface temperature (SST) cooling and deepening of the mixed layer was investigated herein using an optimally interpolated (OI) cloud-free sea surface temperature (SST) dataset, climatological profiles of water temperature, and data from Argo profilers. SST data showed a maximum cooling of 1.7–6.5 °C during 1–7 June 2007 over the study area, which is similar to that of slow- to medium-moving cyclones in previous studies. The oceanic heat budget equation with the assumptions of the dominant turbulent mixing effect was used to establish relationships between SST and mixed layer depth (MLD) for regions that were directly affected by cyclone-induced turbulent mixing. The relationships were applied to the SST maps from satellite to obtain maps of MLD for 1–7 June, when Gonu was over the study area. Comparing with the measured MLD from Argo data showed that this approach estimated the MLDs with an average error of 15%, which is an acceptable amount considering the convenience of this approach in estimating MLD and the simplifications applied in the heat budget equation. Some inconsistencies in calculating MLD were attributed to use of climatological temperature profiles that may not have appropriately represented the pre-cyclone conditions due to pre-existing cold/warm core eddies. Estimation of the diapycnal diffusion that quantified the turbulent mixing across the water column showed consistent temporal and spatial variations with the calculated MLDs.

Water Mass Transformation and Overturning Circulation in the Arabian Gulf

AbstractWe diagnose the ocean’s residual overturning circulation of the Arabian Gulf in a high-resolution model and interpret it in terms of water-mass transformation processes mediated by air–sea buoyancy fluxes and interior mixing. We attempt to rationalize the complex three-dimensional flow in terms of the superposition of a zonal (roughly along axis) and meridional (transverse) overturning pattern. Rates of overturning and the seasonal cycle of air–sea fluxes sustaining them are quantified and ranked in order of importance. Air–sea fluxes dominate the budget so that, at zero order, the magnitude and sense of the overturning circulation can be inferred from air–sea fluxes, with interior mixing playing a lesser role. We find that wintertime latent heat fluxes dominate the water-mass transformation rate in the interior waters of the Gulf leading to a diapycnal volume flux directed toward higher densities. In the zonal overturning cell, fluid is drawn in from the Sea of Oman through the Strait of Hormuz, transformed, and exits the Strait near the southern and bottom boundaries. Along the southern margin of the Gulf, evaporation plays an important role in the meridional overturning pattern inducing sinking there.

Interference of CDOM in remote sensing of suspended particulate matter (SPM) based on MODIS in the Persian Gulf and Oman Sea

The spatial and temporal variability of suspended particulate matter (SPM) in the Persian Gulf and Oman Sea coastal waters has remained challenging to understand among researchers. Here, for the first time in the region, we parametrized SPM concentration in the study area utilizing derived remote sensing reflectance (Rrs) values from Moderate-resolution Imaging Spectroradiometer (MODIS), using 555 and 667 nm wavelengths. Likewise, the findings showed that the developed optical model based on the optical ratio of Rrs (667)/Rrs (555) was sensitive to the concentration of Chromophoric dissolved organic matter (CDOM) in the seawater, within the visible wavelengths less than 600 nm. Comparing the new estimates of the SPM concentration with in situ measurements by Spearman's Rank correlation for validation revealed that the association between estimated and measured SPM concentration would be considered statistically significant (ρ up to 0.86, p < 0.05). This study increased the average accuracy of the estimates up to 73%.

Assessment of water security in the large watersheds of Iran

The present study was conducted to evaluate the water security in Iran and its large watersheds over a period of 20 years at 5-year intervals (1996, 2001, 2006, 2011, and 2016). Eight important indicators influencing the water security including the renewable water resources per capita, water use intensity, water productivity, investing in water infrastructures, water quality, access to drinking water and pollution management, changes in the green coverage area, and changes in the large water bodies area of the country were used and weighed by the analytical network process (ANP) method in order to quantify the concept of water security. The average calculated values for water security were equal to 0.455, 0.442, 0.410, 0.345, 0.326, and 0.323 in the Urmia Lake, Caspian Sea, Persian Gulf and Oman Sea, Qaraqom, Central Plateau, and Eastern Border large watersheds, respectively over 20 years. The calculated values for water security during the studied years showed that although the slope of water security has changed in different time periods, but the water security declined between 1996 and 2016 across the six watersheds although there were some small discrepancies in this trend. These inconsistencies are far less significant than the overall reductions in water security across time and space. Considering that water security is one of the important components of national security and existence of water crises, sustainable management of water resources by political, social and economic requirements and creating a proper balance between water use and water resources seems necessary to prevent a possible future.

The Effect of Monsoon on Chemical Composition and Bioaccumulation of Heavy Metals in Scomberomorus commerson, Lacepede 1800, from 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 post-monsoon 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 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.

Insights toward the future potential distribution of mangrove crabs in the Persian Gulf and the Sea of Oman

Mangroves are an ideal habitat for brachyuran crabs because of nutritional and shelter support. Using maximum entropy (MaxEnt) modeling technique, we projected the potential global distributions of 10 dominant species of mangrove crabs from the Persian Gulf and the Sea of Oman under future climate change. The highest species richness of mangrove crabs was in the Northeast Persian Gulf, including the Strait of Hormuz and Qeshm Island, as well as the North Sea of Oman. Our results revealed that depth and sea surface temperature (SST) were the most important drivers of distribution of mangrove crabs. The most potential suitable environments are located along the coastal areas of the Persian Gulf, and the Sea of Oman, where the depth is <16.89 m, temperature is between 27.70 and 28.08°C, salinity is between 37.21 and 40.61 PSS, and currents velocity is between 0.01 and 0.05 m−1 for the present output models. Future distribution model outputs showed that, areas with depth <3.12 m, temperature between 28.53 and 28.92°C, salinity between 37.21 and 40.63 PSS, and current velocity between 0.01 and 0.05 m−1 were the most suitable environments for future potential distributions of mangrove crabs. MaxEnt model outputs revealed that five species (50%) will expand and the remaining (50%) will shrink in their future distribution ranges. The model outputs predicted that some of the species might lose their habitat in future, and some might invade other ecosystem as invasive species. These findings thus highlight not only the vulnerability of mangrove crabs to habitat loss, but also alert their potential invasions to other ecosystems due to future climate changes. This outcome should be considered as a basic guideline for species management of mangrove systems. Mangroven sind ein idealer Lebensraum für Brachyurenkrebse, da sie ihnen Nahrung und Schutz bieten. Mithilfe der MaxEnt-Modellierungstechnik (Maximum Entropy) haben wir die potenzielle globale Verbreitung von zehn dominanten Arten von Mangrovenkrabben aus dem Persischen Golf und dem Oman-Meer unter zukünftigen Klimaänderungen projiziert. Der höchste Artenreichtum an Mangrovenkrabben wurde im Nordosten des Persischen Golfs, einschließlich der Straße von Hormuz und der Insel Qeshm, sowie in der Nordsee von Oman festgestellt. Unsere Ergebnisse zeigen, dass Tiefe und Meeresoberflächentemperatur (SST) die wichtigsten Faktoren für die Verbreitung von Mangrovenkrabben sind. Die potenziell geeignetsten Gebiete befinden sich entlang der Küsten des Persischen Golfs und des Omans, wo die Tiefe weniger als 16,89 m, die Temperatur zwischen 27,70 und 28,08°C, der Salzgehalt zwischen 37,21 und 40,61 PSS und die Strömungsgeschwindigkeit zwischen 0,01 und 0,05 m-1 liegt. Die Ergebnisse des Modells für die künftige Verteilung zeigten, dass Gebiete mit einer Tiefe von weniger als 3,12 m, einer Temperatur zwischen 28,53-28,92°C, einem Salzgehalt zwischen 37,21-40,63 PSS und einer Strömungsgeschwindigkeit zwischen 0,01-0,05 m-1 die am besten geeigneten Umgebungen für die künftige potenzielle Verteilung von Mangrovenkrabben sind. Die Ergebnisse des MaxEnt-Modells zeigten, dass sich fünf Arten (50 %) in ihren zukünftigen Verbreitungsgebieten ausbreiten und die übrigen (50 %) schrumpfen werden. Die Modellergebnisse sagten voraus, dass einige der Arten ihren Lebensraum in der Zukunft verlieren könnten, und einige könnten als invasive Arten in andere Ökosysteme eindringen. Diese Ergebnisse verdeutlichen nicht nur die Anfälligkeit der Mangrovenkrabben für den Verlust ihres Lebensraums, sondern machen auch auf ihre mögliche Invasion in andere Ökosysteme aufgrund künftiger Klimaänderungen aufmerksam. Dieses Ergebnis sollte als grundlegende Leitlinie für das Artenmanagement in Mangrovensystemen betrachtet werden. Figure S1. Global distribution of six families from mangrove crabs. Figure S2. Morphological characteristics of Camptandriidae. Figure S3. Morphological characteristics of Camptandriidae and Sesarmidae. Figure S4. Morphological characteristics of Dotillidae (Ilyoplax frater and Ilyoplax stevensi). Figure S5. Morphological characteristics of Dotillidae (Dotilla blanfordi and Scopimera crabricauda). Figure S6. Morphological characteristics of Macrophthalmidae and Oziidae. Figure S7. Morphological characteristics of Ocypodidae. Figure S8. Latitudinal range of mangrove crabs according observed data, as well as, Present and Future distribution models. Figure S9. The ability dispersal of mangrove crabs in response to climate change in future. Table S1. Outputs of response curve in MaxEnt model. Table S2. The percentage of the suitability of environment for each species. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.