Journal of the Persian Gulf (Marine Science)
Volume:4 Issue: 13, Fall 2013

Egg envelope or otherwise called zona radiata (ZR) is an acellular area that originates next to oolemma externally. It grows and thickens gradually from oolemma and follicular epithelium both. Microscopic studies on the tissue sections hava shown that during developmental stages of oocytes, ZR could not be observed at stage I (Primary growth stage) in Acipenser persicus. It appeared in stage II (Cortical alveolar stage) and during stage III (vitellogenesis), ZR thickness was greatest and had highest complexity. The striated appearance of ZR at this stage, were identified to be pore-canals involved in yolk material transportation. In stage IV (Maturation stage), a decline was observed in ZR thickness and complexity, a process which continued after fertilization. In mature egg, an uneven layer of chorion over ZRe (ZR, external) and a jelatinous coat extrachorion were developed. Immediately after fertilization, ZRi (ZR, internal) turned to a homogenous layer (fertilization envelope), probably because of cortical reaction. 30 minutes after fertilization, two layers recognized in ZRi and chorion and extrachorion were disappeared.

Gastropod assemblages were investigated along intertidal rocky shore in the Qeshm Island in the northern Persian Gulf. Monthly sampling was undertaken from May 2007 to April 2008. Environmental factors were also measured in each site. A total of 28 gastropod taxa belonging to 15 families were identified and Cerithiidae was the most abundant family and Cerithium caeruleum was the most abundant species (34.77%). Muricidae with 5 species were the most diverse group followed by Cerithiidae and Cypraeidae each with 4 species. Kruskal-Wallis test yielded no significant differences in gastropod assemblages among months and also different seasons (P>0.05). The analysis of SIMPER showed that spring and autumn had the most dissimilarity among seasons and Clypeomorus bifasciatus was the species of gastropods contributing most to the dissimilarities among seasons (37.54%). December showed the highest value of Shanon-Wiener (2.15) and Simpson (0.85) indices. Lack of significant temporal variation in gastropod assemblages during sampling months suggested that intensity of sampling in future studies could be reduced to seasonal intervals in similar environmental conditions.Where intertidal surveys are restricted by time,and resources such as, personnel and finance.

The objective of this study is to understand the calcareous nannoplankton response to past environmental changes in the Strait of Hormuz during the Holocene. Calcareous nannoplankton is well abundant in the living phytoplankton community and a key component of the marine sediments. Due to its distinct reaction to environment changes and its good preservation potential, it is well suited for paleoceanographic reconstructions. Therefore, the study of the calcareous nannoplankton is indicative for paleoceanographic changes in the Strait of Hormuz. For this purpose, 15 samples of surface sediments of the Strait of Hormuz are selected and 27 species and 16 genera are introduced. In this study, we have observed 3 groups of calcareous nannofossils. These groups included abundant taxa, rare taxa and reworked taxa. We study all samples of the Strait of Hormuz for detecting the total organic carbon content. They have shown that there is a relationship between TOC, CaCO3 and productivity of calcareous nannofossils. Some samples include high TOC and CaCO3 values and they are correlated to high productivity of calcareous nannofossils. Also due to dilution, some samples showed a negative relationship between TOC and CaCO3. Some specific element compositions of this region were analysed and then we studied the relationship between them and relative abundances of calcareous nannofossils. Some elements like Ba, Cu and Zn reveal a close relationship to fertility of calcareous nannofossils and they are highly enriched in the nutrient-rich waters of strait of Hormuz. Ba, Cu and Zn content and relative abundances of nannofossils were high in the near shore of Strait of Hormuz. The distribution pattern of the Si content shows a persistent minimum in this area. This element have shown a negative relation to productivity of calcareous nannofossils. Relying on information, we can conclude the coast of Strait of Hormuz is affected by upwelling and it is an appropriated environmental aspect of nutrients and productivity.

Total organic carbon has a major influence on both the chemical and biological processesthat take place in sediments. Algal bloom is one of the organic carbon levels in aquatic ecosystems. In 2009 algal bloom occurred in the Hormozgan province and prolonged for months, which finally setteled down in 2010. In this study the variations of total organic carbon (TOC), organic matter (TOM) and total nitrogen (TN) contents, and the carbon-nitrogen ratio in superficial sediments collected from 33 stations at the Strait of Hormuz were investigated. Sampling was performed at the depths of 14 to 59 meters in spring of 2010 after sinking algal bloom in the area.The TOC content in the surface sediments revealed values in the range of 0.5 up to 3.5 % (mean 2 %, median 2.2 %, standard deviation 1.3%). The values generally highlighted a gradient increasing with distance from the Strait of Hormoz. According to the standards of Environmental Protection Agency of United State, the organic carbon concentrations in the analyzed sediments were in the range of sediments with low to medium organic carbon level. Organic matter levels were in the range of 4.4 to 10 % (mean 7.3 %). Statistical analysis demonstrated that there were no significant differences between the stations. According to Pearson correlation, total organic matter and organic carbon had significant correlation with each other (R2=0.81, P=0.01). Results showed that deeper parts had relatively higher organic carbon level (R2=0.66, P=0.05).Our investigation showed that the accumulation pattern of organic carbon depended on the grain size of the sements. The stations with higher percent of silt and clay had higher organic carbon. The results revealed that organic carbon level has increased in resent years, which can influence on the potential of methylation and accumulation of metals in sediment. In this study the TOC/TN ratio for 33 sediments were between 3 and 8, which demonstrated that the source of organic carbon could be related to the recent algal bloom.

People are motivated according to their needs. These needs vary according to the time and based on various situations. Identifying and assessing human needs are the first and vital step in determining the amount of its impact on work and activity. According to these facts, the aim of this research is to identify the needs of the Iranian seafarers on board merchant ships. It also tries to specify the importance and priority of these needs in the frame of “Maslow’s hierarchy of needs” theory. Research methodology is analytical and based on library resources and previous studies. Research was conducted using interview and questionnaire. 96 questionnaires were distributed among Iranian seafarers of which 94 questionnaires were completed and evaluated valid for further processing. Surveyed population included masters, officers and engineers on board container ships, bulk carriers, tankers, special ships and general cargo vessels. The results showed that self-actualization and self-esteem are the most important needs of the seafarers and the physiological needs ranked the lowest.

Taxonomic study of the genus Padina (Dictyotales, Phaeophyceae) from the Persian Gulf coast was conducted based on morphology and molecular phylogenetic analyses using chloroplast encoded large subunit RuBisCo (rbcL) gene sequences. Detailed descriptions of each species found in this study are described. Several morphological characters, such as number of cell layers composing the thallus, presence or absence and degree of calcification, presence or absence of small groups of rhizoid-like hairs, structure, position and arrangement of hairlines, presence or absence of indusium and reproductive sori, are considered to be reliable morphological characters for species delineation. In this study, it was realized there were 12 new sequences among the samples examined and as such, based on the rbcL sequences, four species could be tentatively delineated along the Persian Gulf coast: Padina sp.FA, Padina sp.PG, Padina sp.INDEGR032 and Dictyota ciliolate Sonder ex Kützing 1859. Further work is required to complete description of new species based on morphology and molecular analyses.

The importance of Uromie Lake National park and Biosphere Reserve associated with is known worldwide; and thus, maintaining its optimized well-being and values are on the priority list of preserving, rehabilitation and ecologic management programs. Plants, as primary producers of the greater Uromie Lake ecosystem, despite their greater diversity have covered much lesser areas primarily because of climate change and disturbing human activities. Natural phenomena have caused for the Uromie Lake to retrogress and dry out in many areas, leaving bare lands behind, providing the opportunity for farmers to grasp more land for farming practices and in some areas, natural populations of halophyte plants pioneer. We do not know, how much of the plant success is because of natural processes, such as plant symbiosis, and thus, acquires further investigation. In this paper, results of a preliminary survey on soil and frequent plant species communities are presented, probable natural causes contributing to retrogression of Uromie Lake and potentials of using plant pollen and fungal spores records for determining past lake behavior are discussed.