Journal of Marine Science

Journal Information
EISSN : 2661-3239
Published by: Bilingual Publishing Co. (10.30564)
Total articles ≅ 61
Filter:

Latest articles in this journal

Laurențiu-Florin Constantinoiu, , Maria-Emanuela Mihailov
Published: 30 April 2022
Journal of Marine Science, Volume 4, pp 7-17; https://doi.org/10.30564/jms.v4i2.4497

Abstract:
This paper aims to provide the reader with the results of the Unexploded Ordnance (UXO) survey of the defensive historical naval minefields launched by the Romanian and German Navies on the Romanian Black Sea coast, during the Second World War. This UXO survey was carried out between 2015-2018 by the Romanian Navy’s hydrographic ship “Commander Alexandru Cătuneanu” and Romanian Mine Warfare Data Center, using towed side-scan sonar technology and oceanographic observations. After explaining the materials and methodology, the results are presented and discussed: mosaics of the minefields, side-scan images of UXO contacts, side-scan images of the wrecks that were sunk in the minefields and some visible natural geological features of the seafloor. It was concluded that most of the objects discovered are sinkers, wreck debris or parts of chains, which does not represent a danger to navigation.
Yanli Sun
Published: 30 April 2022
Journal of Marine Science, Volume 4, pp 1-6; https://doi.org/10.30564/jms.v4i2.4454

Abstract:
“The 21st century is the century of the ocean.” In recent years, China has paid more and more attention to the promotion and development of the marine industry, especially the ocean fishery has brought immeasurable economic benefits to China. The development of the marine field is becoming more and more important in the national political, economic and cultural development. All coastal countries have included marine development in their national development strategies and continuously improved their marine legislation under the provisions of the United Nations Convention on the law of the sea. China’s pelagic fishing began in 1985, but because China’s pelagic fishing started too late, after the entry into force of the United Nations Convention on the law of the sea at the end of 1994, nearly 36% of the richest high seas on earth became the exclusive economic zone of coastal countries, and the development space of China’s pelagic fishing has become very limited. After just more than 30 years of development, ***. However, before that, China’s pelagic fishing was still subject to the dual norms of international conventions and domestic laws, and China had not yet formulated a special law on pelagic fishing, and there were still many deficiencies in the legal system norms of pelagic fishing. Therefore, the biggest problem facing China’s pelagic fishery is how to better develop the marine industry under the system of laws and regulations, drive the coordinated economic development, provide legal guidance and help for pelagic fishermen, and provide solid technical support for building a marine power with Chinese characteristics.
Mona M. Sharabash, Samia S. Abouelkheir, Mona E. M. Mabrouk, Hanan A. Ghozlan, Soraya A. Sabry
Published: 12 January 2022
Journal of Marine Science, Volume 4; https://doi.org/10.30564/jms.v4i1.3875

Abstract:
Agar is an essential polysaccharide that has been utilized in numerous fields. Many kinds of literature have been published regarding agarolytic microorganisms’ isolation and agarases biochemical studies. In this search, a local marine agarolytic bacterium associated with marine alga Ulva lactuca surface was isolated and identified as Pseudoalteromonas sp. MHS. The agarase production was parallel to the growth of Pseudoalteromonas sp. MHS as cells displayed a lag phase (2 h), subsequently an exponential growth that prolonged till 10 h where maximum growth (OD550nm = 3.9) was achieved. The enzyme activity increased rapidly as cells increased exponentially where the maximum activity of 0.22 U/mL was achieved after 8h and remained constant till 12 h during the stationary phase of growth. Agarase production was optimized using Plackett-Burman statistical design by measuring enzyme activity as a response and the design was validated using a verification experiment; the activity of the enzyme increased from 0.22 U/mL to 0.29 U/mL. Pseudoalteromonas sp. MHS agarase was partially purified and its molecular weight (MW) was determined by SDSPAGE (15-25 kDa). Agarase showed approximately 94% of its activity at 40 °C. The enzyme stability decreased as the temperature increased; the enzyme could retain about 98, 90, 80, 75, and 60% of its activity at 20, 30, 40, 50, and 60 °C, respectively. Biomass of the red alga Pterocladia capillacea proved to be a suitable substrate for agarase production using Pseudoalteromonas sp. MHS; the enzyme activity recorded after 24 h of incubation was 0.35 U/mL compared to 0.29 U/mL from the optimized medium.
Okpuvwie Ejuvweyere Jonathan, Garba Mustapha
Published: 12 January 2022
Journal of Marine Science, Volume 4; https://doi.org/10.30564/jms.v4i1.3785

Abstract:
Any seafarer or mariner that uses the sea knows that navigation without correct charts is impossible and hazardous because nautical charts are the most essential and indispensable tools for vessels to sail safely at sea. For vessels to safely sail at sea, the seas and the oceans ought to be charted and this falls within the domain of hydrography. However, the seas cannot be charted effectively in the absence of the deployment of human resources and adequate tools like satellite and aerial imagery, survey boats and other equipment that will facilitate the hydrographic operations. The acquisition of data and information about the sea depths, nature of sea bed, waterways, navigational hazards and navigational objects among others, basically falls within the sphere of hydrography which is primarily known as survey at sea. The paper offers a review of geospatial technologies in hydrographic practice for enhanced safety of navigation at sea. The review is important to both the mariners, shipping industry and the government in order to explore the potentials provided by Geographic Information System, Remote Sensing, cloud GIS, big data GIS and Global Positioning System to enhance the practice of hydrography. The data and materials used for the review were obtained from literature in the internet and other published works. The paper looked at hydrography as a profession, roles of geospatial technologies in hydrographic practice, benefits of hydrography to national development and finally, the weaknesses of geospatial technologies in hydrographic practice were equally examined.
Qianrong Li, Baoji Zhang
Published: 12 January 2022
Journal of Marine Science, Volume 4; https://doi.org/10.30564/jms.v4i1.4115

Abstract:
The resistance performance and motion stability of deep sea remotely operated vehicles (ROVs) subjected to underwater motion conditions are studied on the basis of the unsteady Reynolds-averaged Navier-Stokes method combined with the six-degree-of-freedom equation of motion to quickly and accurately predict them. In the modeling process, we consider the complexity of ROV geometry and thus reduce the model to a series of regular geometries to maximize the position and weight of the original components. The grid and value slots of an ROV are divided, and the surface is reconstructed. The forward, backward, transverse, floating, and submerged resistance of ROVs are simulated and compared with existing experimental forces to determine the accuracy of the calculation method. Then, the oblique navigation of the ROV on the horizontal and vertical planes is studied. Furthermore, the motion response of the ROV to direct horizontal motion, heave, pitch, and yaw are studied. The force, moment, and motion time curves are obtained. The stability of ROV motion is analyzed to provide technical support for the safety of ROVs.
Egai Ayibawari Obiene, Eteh Desmond Rowland, Inko-Tariah Ibiso Michael
Published: 12 January 2022
Journal of Marine Science, Volume 4; https://doi.org/10.30564/jms.v4i1.4197

Abstract:
The use of Digital Shoreline Analysis System was used to determine shoreline changes in Ikoli River, Yenagoa, Bayelsa State. Shoreline data were extracted from satellite imagery over thirty years (1991-2021). The basis of this study is to use Digital Shoreline Analysis System to determine erosion and accretion areas. The result reveals that the average erosion rate in the study area is 1.16 m/year and the accretion rate is 1.62 m/year along the Ikoli River in Ogbogoro Community in Yenagoa, Bayelsa State. The mean shoreline length is 5.24 km with a baseline length of 5.2 km and the area is classified into four zones to delineate properly area of erosion and accretion based on the five class of Linear regression rate, endpoint rate and weighted linear rate of which zone I contain very high erosion and high erosion with an area of landmass 255449.93 m2 of 38%, zone II contain moderate accretion, very high accretion and high accretion with a land area of 1666816.46 m2 with 24%, zone III has very high erosion and high erosion with an area of landmass 241610.85 m2 of 34 % and zone IV contain moderate accretion and high accretion with land area 30888.08 m2 with 4%. Out of the four zones, zone I and II were found to be eroding with 72% and zone II and IV contain accretion with 28%. The result shows that 44% of the area have been eroded. Therefore, coastal engineers, planners, and shoreline zone management authorities can use DSAS to create more appropriate management plans and regulations for coastal zones and other coastal parts of the state with similar geographic features.
Jonathan Ejuvweyere Okpuvwie
Published: 25 October 2021
Journal of Marine Science, Volume 3; https://doi.org/10.30564/jms.v3i4.3810

Abstract:
Humans rely on the sea for food and mineral resources; hence it is vital to their economic survival. Nations all throughout the world rely on the water for trade and commerce. This article looks at the present condition of marine security in the Gulf of Guinea. The Gulf of Guinea has a total shoreline of about 5,000 nautical miles and several natural harbours with dangerous weather. It has a significant crude oil reservoir, as well as fish and other natural resources. These traits provide huge prospects for marine trade and transportation, but the Gulf of Guinea is also riddled with maritime crimes of all types, including piracy and smuggling. Maritime piracy has presented a threat to coastal states’ stability and economic viability all across the world, not only in Africa. The study examines sea piracy in general, the Geographic Information System, and the impact of maritime piracy on the world socioeconomic development using secondary data. It then goes on to provide a number of recommendations aimed at addressing the problems caused by maritime piracy in the Gulf of Guinea in order to improve maritime security.
Niki Shah, Yashesh Shah
Published: 25 October 2021
Journal of Marine Science, Volume 3; https://doi.org/10.30564/jms.v3i4.3851

Abstract:
Present short communication reports about beach stranding of Porpita porpita (Linnaeus 1758) from the Coast of Mandvi, Kutch during August 2021. Also, this is the first record of the blue button jellyfishes for the northern Gulf of Kutch region. A study was carried out by primary observation and measurements of common environmental parameters such as Sea Surface Temperature (SST), Wind Direction & Wind Speed. Aboral and oral parts were observed and described. It is assumed that the large biomass of blue button jellyfish on the beach is due to strong shoreward Monsoon winds.
Back to Top Top