فهرست مطالب

Journal of the Persian Gulf (Marine Science)
Volume:3 Issue: 7, Spring 2012

  • تاریخ انتشار: 1391/04/26
  • تعداد عناوین: 7
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  • Simin Dehghan, Madiseh, Seyed Mohammad Baghe Nabavi, Jasem Ghofleh, Marammazi, Najmeh Jahani, Emad Koochaknejad Page 1
    Khuzestan coastal waters have high fisheries potential and ecological importance. Since different sources of stress exist in this area, the present study was conducted to evaluate ecological quality and to determine health status in Khuzestan coastal sediments based on benthic communities and their biological parameters. Seasonal sampling was done from 20 creeks of Khur-e-Mussa area in Khuzestan coastal waters by 0.125 m2 Peterson grabsampler during winter 2008 to autumn 2009. Macro– invertebrates were separated, sorted and identified to the lowest possible taxon. In addition, biological parameters such as diversity, richness, biomass and abundance were calculated. The results were analyzed using univariate analysis method, ABC (Abundance–Biomass Curve). The most abundant groups were polychaets (58%), crustaceans (25%) and mollusk (9%), respectively. The ABC plots showed that majority ef creeks could be classified as moderately disturbed and polluted. The ranges of H' diversity index values in majority of stations indicated moderate ecological status.
    Keywords: ABC (Abundance, Biomass Curve), Benthic communities, Khur, e, Mussa area, Khuzestan coastal waters
  • Omid Nejadkazem, Ahmad Reza Mostafa, Gharabaghi Page 11
    Usually, evanescent modes or non-propagating waves are produced when a propagating incident wave impinges on an interface between two media or materials such as curtainwall-pile breakwater (CPB) at a subcritical angle and decay with distance from interface. To achieve an effective prediction of hydrodynamic performance of CPB and overcome the problem of underestimation of energy loss, the effect of non-propagating waves is considered. A numerical model was developed that can predict the interaction of irregular waves normally incident upon a CPB. The developed numerical model is based on an eigenfunction expansion method. The model utilizes a matching boundary condition nearby the vertical piles which accounts for energy dissipation. The accuracy and validity of the method were verified by comparison with results obtained by other authors. Furthermore, the nature of contraction coefficient is discussed and a new predictive formula is presented and compared with the former one suggested by Mei et al. (1974). The proposed contraction coefficient which comprises the hydrodynamic characteristics of waves enhances efficiency and effectiveness of estimation in comparison with other formulas. Non-propagating waves can affect wave propgation and scattering near permeable barriers. These effects have been analyzed and optimum number of necessary corresponding evanescent modes have been studied. Although, it is found that the first 5 evanescent modes strongly alter the results and stabilize them, greater reliability may be achieved by taking twenty waves into account.
    Keywords: Curtainwall, pile breakwaters, Evanescent modes, Eigenfunction expansion, Contraction coefficient
  • Seyed Yousef Paighambari, Moslem Daliri Page 27
    This paper is a comprehensive study of the shrimp trawl by- catch from Bushehr coastal waters (N. Persian Gulf). Sampling operation was carried out in two shrimp fishing seasons using the (Saber and Jahanara) commercial trawlers Generally, 87.5% of the total catch was by-catch and 12.5% was target species (shrimp). The catch composition included: 114 species from 45 teleostei families, 13 species from 7 elasmobranchs families and 13 species from 13 invertebrate families. Species composition of By-catch included: 72% teleosts, 14% elasmobranchs and 13.9% invertebrates. By-catch-to-shrimp ratio, CPUE index and catch percentage of species (based on Wt %) were computed. On average By-catch-to-shrimp ratio was estimated 7:1. It’s estimated that 283.4 tonnes of By-catches are taken annually in Bushehr coastal waters by 12 steel trawlers.
    Keywords: Shrimp, Bottom trawl, By, catch, Bushehr, Persian Gulf
  • Hassan Zare, Maivan Page 37
    Biological response and ecological indices of benthic communities, such as greater mortality of foraminifera and shell abnormalities, have been used to document pollution effects on ecosystems. Shadegan Wetland was damaged from a deposition of huge amounts of soot and products of burning oilwells of Kuwait as well as chronic exhaust fumes of refinery and industrial furnaces. In this investigation, community structure and changes in indices of the macro- and meio-fauna of the Shadegan wetland were studied in 2004. Recorded salinity ranged from 4.1 to 63.1 ppt. Salinity varied significantly among sampling stations. pH of the water fluctuated between 6.8 to 8.7. Dissolved oxygen (DO) content of water at the sampling stations ranged from 5.3 to 7.8 mg / l. The maximum and minimum (19.6 and 7 NTU) water turbidities were recorded at the sampling stations 7 and 10, respectively. The maximum and minimum TOM (23.17% and 8.45%) were recorded at stations 3 and 9, respectively. The results of sediment texture analysis showed that soil type in the study area was mostly silty–clay. The highest and the lowest rate of sediment with silty – clay texture were 89.76% and 49.28%, respectively. 18 species of macrobenthos were identified. Gastropods comprised more than 50% of the individuals of macrobenthos populatiopns. Aquatic insects (22%), Crustaceans (11%), Polychaetes and Acaris (each with 5.5%) were the other dominant groups in abundance, respectively. The results showed the highest (984 / m2) and the lowest (26/m2) abundance of macrobenthos were recorded at the stations 10 (Rogbeh) and 8 (Doragh creek), respectively. The results showed that meiobenthos displayed a higher biodiversity than macrobenthos. Ostracodes, Nematods and Foraminifera were the most dominant groups. Many Foraminifera showed morphological shell abnormality. Biodiversity indices (H′ and λ) for macrobenthos and meiobenthos were expectedly different. Meiobenthos, primarily,Ostracodes, Nematods and Foraminifera displayed higher biodiversity than macrobenthos. ANOVA results showed significant variation (P < 0.05) between sampling stations.
    Keywords: Shadegan wetland, Macrobenthos, Meiobenthos, Ecology of Shadgan Wetland
  • Homira Agah Hashtroudi, Willy Baeyens Page 45
    The concentrations of sixteen elements and organic carbon were determined in 78 marine sediment samples collected from the Iranian coastal waters of the Persian Gulf. Nine transects perpendicular to the coastline were sampled. Sixteen elements, including As, Ba, Cd, Co, Cu, Mn, Ni, Pb, Zn (trace metals) and Ca, Fe, Mg, Na, P, S, Si (major metals), were determined by Inductively Coupled Plasma Mass Spectrometry (ICP MS) and Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES), respectively. In this study, the element concentrations in sediments have not exceeded the sediment quality guidelines and pose no environmental concerns with the exception of Ni, which is over than ERM. The spearman correlation matrix demonstrated that all elements except for arsenic, cadmium, barium and silicon, were significantly (P<0.01) correlated with iron. The Relative Contaminated Factor (RCF) for elements which had ISQG values and Enrichment Factors (EF) using Fe demonstrated that there was no metal enrichment by natural or anthropogenic sources except for Ni. High EF level for Ni demonstrated that nickel level in sediments of the Persian Gulf could have originated from anthropogenic sources.
    Keywords: Persian Gulf, Sediment, Trace metals, Major elements, ICPMS, AES
  • Amir Saeed Nooramin, Mansoor Kiani Moghadam, Ali Reza Moazen Jahromi, Jafar Sayareh Page 59
    The time that containerships or transportation trucks spend in marine container terminals for loading and unloading their cargo is a real cost scenario which affects, not only the smooth operation of ports, but also affect the overall cost of container trade. The operators of shipping lines and container terminals are required to realize the importance of this issue and the costs associated with dealing long queues of ships and trucks at loading or discharging ports. This paper introduces the concept of the classical Analytical Hierarchy Process (AHP) together with the Fuzzy AHP (FAHP) to help the decision makers in their judgments towards implementing costly loading and discharging facilities at their container terminals. The main objective of this study is to provide a decision-making tool and also to introduce the concept of the Multiple Attribute Decision-Making (MADM) technique by using and comparing both of the AHP and FAHP techniques for solving the problem of selecting the most efficient container yard gantry crane amongst three alternatives including Straddle Carriers (SCs), Rubber Tyred Gantry Cranes (RTGs), and Rail Mounted Gantry Cranes (RMGs) by incorporating the quantitative and the qualitative determining attributes into the problem. Both of the AHP and FAHP analyses in this study have shown that RMG, RTG, and SC systems are the best operational alternatives, respectively.
    Keywords: Decision, making, Fuzzy sets, Container terminal, AHP, FAHP
  • Masoud Sadrinasab, Seyed Taleb Hosseini Page 71
    Bushehr Bay is situated along the northern Iranian coasts of the Persian Gulf, between 28°52΄ and 29°5΄ north latitude and 50°42΄ and 50°52΄east longitude. In this study COHERENS, which is a threedimensional hydrodynamic model, was employed to simulate surface and under surface currents in the Bushehr Bay. The atmospheric forces and four main tidal constituents M2, S2, K1, O1 and also boundary forces were applied in the model. The simulation results and observations showed that the current in the Bushehr Bay was dominated by tide-driven currents.
    Keywords: Flood currents, Ebb currents, Seasonal currents, Bushehr Bay, Persian Gulf