Journal of the Persian Gulf (Marine Science)
Volume:9 Issue: 33, Fall 2018

In this research, the relation between the time series Carangid fishes (Carangidae) CPUE data in Sistan-Baluchestan waters with the environmental effective data including sea surface and air temperature, chlorophyll a, evaporation rate and rainfall as parameters of climate change indicators have been studied monthly during 2007 – 2018. GLM and GAM regression were used for data analysis. The results showed significant decrease in carangid species. In this regard, the two factors of SST and air temperature have had an increasing and both SST and air temperature showed significant relationship with Scomberoides commersonianus and other carangid species CPUE stocks. Finally, it seems that in order to maintain the carangids fish stocks due to the various effects of climate change and environmental factors, and human activities particulary, need to reform fisheries regulatory management.

Climate change resulting from anthropogenic activities and subsequent increase in greenhouse gases with the potential to directly affect temperature, light, salinity, changes in wind and precipitation patterns, changes in organic matter and water pH, and rise of sea levels is one of the most important and challenging topics in oceanography and biology.  Therefore, it seems necessary to study the effects of climate change on marine aquatic organisms especially microalgae as primary producers in marine ecosystem. Research shows that global warming and rise of sea temperatures have negative effects on photosynthetic microalgae, however, increase the density and the bloom of harmful algae. The study of harmful microalgae as a potential of environmental hazard for aquatic organisms and even humans has a special interest because some of these microalgae are toxic to the marine organisms and cause a lot of damage on the fisheries and aquaculture industry. Research shows that the rate of growth and blooms of harmful microalgae has reached its highest level in the last 4 decades as the result of significant climate change and further warming, and their pattern of accumulation, life strategy, distribution have changed under the probable influence of climate change. The present study has reviewed effect of climate change on marine environments and especially on microalgae; and has aimed to evaluate the challenges and consequences of increased blooms of harmful algae, algae toxins on marine ecosystem and human health.

Length-weight relationship (LWR) was estimated for 86 caught black pomfret by trawl net in Qeshm Island located in the Persian Gulf in in March 2017. The total length and total weight of the fish ranged from 15.8 to 56.2 cm and 69 to 3128 g, respectively. The mean total length and total weight were 25.08 ± 0.76 cm and 358.93 ± 52.22 g, respectively. LWR for black pomfret was W = 0.0267L2.875 (R2 = 0.975). The results obtained can be valuable for improvement of the technical performances related to fisheries management in the future.

This paper studies the ice formation in the Caspian Sea using HYCOM model which is applied for 18 years to simulate the ice f0rmation in this basin. The vertical layers of 25 are considered, while the horizontal gride is 0.04⁰. The atmosphere forcing, initial condition, and river runoff were some from input files for the whole periods of simulations. The simulation show that the water begins to convert to ice in the middle of December. The maximum ice coverage is recorded in January with a thickness roughly 50 cm. The ice formation begins in the vicinity of the Volga and Ural rivers because of low salinity.

Neurotoxins induce undesirable changes in aquatic organisms. This project assessed the effects of 78.15 g/L aspartame on expression changes of two biomarkers of neurotoxicity (glial fibrillary acidic protein-GFAP and myelin basic protein- MBP) in Cyprinus carpio brain tissue. RNA was extracted from brain tissue. The results of qPCR indicated an increase of 2.5 and 4.2 of MBP and GFAP expression. Elevated levels of these biomarkers suggest the probability of aspartame neurotoxicity. Identifying and monitoring nerve damage using biomarkers can make it easier to diagnose injuries earlier than current methods and provide an opportunity to develop future treatments.

Understanding the wave pattern as a first step in marine studies is very important. The global models as a source of data can be used to simulate local waves. Before applying them, their results should be evaluated. One of the most important global models is the ECMWF model. Based on the wave simulation in the northern coast of the Persian Gulf, it can be said that the ECMWF model results are of good quality for use in local modelling in this area. Also, according to the statistical analysis, the Generalized Pareto and Weibull distributions had the best fit.

In the present study, the structure of macrobenthos communities of Chabahar Bay prior to monsoon in 2016 was investigated. We identified 87 species contain 22 amphipods species, 14 species of other crustaceans, 31 species of molluscs, and 20 polychaets species, where amphipods followed by polychates were dominant taxa. The PERMANOVA test revealed that there is a significant difference in the community structure of macrobenthos at different depths (P <0.05). PERMANOVA Pair-Wise test indicated that this difference is between the communities living in the middle depths (3-15 meters: group C) with intertidal communities (group A, P = 0.008) and shallow areas (group B, P = 0.013). The SIMPER test showed that the two species of Indischnopus herdmani, Ampelisca persicus Momtazi, 2020, as well as Donax cf. bipartitus are the cause of 30% of the difference of dissimilarity between depth groups of C and B. For depth group C and A the Ampelisca persicus Momtazi 2020 and polycatches, especially Pectinaria sp. are responsible for 30%dissimilarity. Our results revealed that the northern and especially the southwest coasts of Chabahar Bay are more structurally diversity than to the middle parts of the bay, therefore extensive environmental studies in middle parts of the bay are recommended with emphasis on sediment pollutants. The results of the present study also point to the importance of the role of depth factor in the distribution of macrobenthos communities, which can help in monitoring strategies and arrangement of sampling stations.

The outfall system is a medium to discharge the liquid waste generated by desalination plants, refineries and power plants to the marine environment. Optimal design and operation of an outfall system reduces the concentration of pollutants returned to the marine environment. Numerous researches have been carried out to study the different elements of outfall systems and related design basics. These studies can be generally divided into three distinct sections: hydraulic design of discharge system, near-field and far-field flow dynamics. In this paper, the outfall system of Bandar Abbas desalination plant is designed and optimized in accordance with an optimization algorithm. For this purpose, the requirements and design criteria of outfall systems are presented and the hydraulic design and salinity distribution are discussed, using CorHyd and VISJET models.