Open Journal of Marine Science
ISSN / EISSN : 2161-7384 / 2161-7392
Current Publisher: Scientific Research Publishing, Inc. (10.4236)
Total articles ≅ 270
Latest articles in this journal
Open Journal of Marine Science, Volume 10, pp 218-232; doi:10.4236/ojms.2020.104017
As habitat and distribution, in the study a total of 18 crab species were identified, belonging to 10 families (Calappidae, Epialtidae, Gecarcinidae, Grapsidae, Matutidae, Ocypodidae, Panopeidae, Sesarmidae, Varunidae, and Xanthidae) order Decapoda under subphylum crustacean with relevant distinguish morphological and meristic character and geographical position. We investigated crab species of Bangladesh from December 2013 to October 2014. All species samples were collected by hand picking on a baseline survey in Saint Martin’s Island (the only coral island of Bangladesh) and adjacent marine water body of Bay of Bengal, Satkhira area (brackish and freshwater) and mangrove forest area (Sundarban). Among 18 species, 10 crab species from Family Epialtidae (1 species), Gecarcinidae (2 species), Ocypodidae (1 species), Panopeidae (1 species), Sesarmidae (1 species) and Xanthidae (4 species) were newly occurred in the Bay of Bengal, Bangladesh. Cardisoma armatum and Zosymus aeneus species were larger than other enlisted species.
Open Journal of Marine Science, Volume 10, pp 203-217; doi:10.4236/ojms.2020.104016
As per the Essential Climate Variables (ESV) of World Meterological Organisation (WMO), the physical, chemical and biological variables critically contribute to the earth’s climate. Among them, the variables such as temperature and pH in the marine environment may affect seriously and in turn it has an impact on the biota, especially in the intertidal environment, where it has brunt force. According to United Nations Framework Convention on Climate Change (UNFCCC), the datasets should provide the empirical evidence needed to predict the climate change and evoluate the mitigation and adaptation measures. Under this context, a review was carried out to know what extent marine scientists understand this factor and what level the biodiversity was evoluated and its impact was analysed in this article. Based on the existing literature review, it was understood that only a few groups that also only few species from these groups were studied in this aspect. The remaining groups and their species and their basic trophic were not evolved in this aspect. So, the marine scientific community, environmentalist and policy makers should take stock on this aspect and give thrust on this study.
Open Journal of Marine Science, Volume 10, pp 32-39; doi:10.4236/ojms.2020.101003
The diversity of phytoplankton communities in marine waters depends on the environmental, physical, chemical and biological factors in which they occur. The aim of our work is to determine the effect of certain physicochemical parameters on the proliferation of five planktonic taxa (1: Alexandrium 2: Dinophysis 3: Gymnodinum; 4: Pseudonitzschia; 5: Proocentrum) identified on the sites of Mehdia and Moulay Bousselham, Gharb of Moroccobetween 2017 and 2018. The results confirm the presence of these toxic taxa in both sites but with different densities. The ACP has allowed separating two distinct groups with coefficients of determination of more than 70%. Indeed, the first group concerning the site of Mehdia, it is characterized by an abundance of the taxa of Gymnodium and Pseudoni, which prefers salt water and oxygenated, thus important phosphate and nitrate levels. Moreover, unlike the temperature factor. However, the second group concerning the Moulay Bousselham site is located on the positive side of the axis, essentially characterized by moderately high temperatures. These conditions are favorable for the Dinophysis, Alexandrum and Proocentrum taxa. This trend makes it possible to classify the Moulay Bousselham site as a risk zone. In light of these results, the authorities of all stakeholders in the sector must increase efforts to overcome this constraint.
Open Journal of Marine Science, Volume 10, pp 41-51; doi:10.4236/ojms.2020.102004
Phytoplankton is all cyanobacteria and microalgae (microscopic plants) present in surface water that may be carried by water currents. The study was conducted at two oceanic sites Mehdia and Moulay Bousselham, Rabat sale Kenitra region, Morocco, between 2017 and 2018. The objective of this study is to compare the spatiotemporal evolution of certain toxic planktonic species between the two sites. The planktonic species identified all have toxic potency but to varying degrees such as Alexandrium, Dinophysis, Gymnodinum, Pseudonitzschia and Proocentrum. The comparison of the abundance of these taxa in the two sites confirms that the Moulay Bousselham site is characterized by the presence of the most toxic planktonic species represented mainly by Pseudonitzschia in contrast the Mehdia site experienced an abundance of the Proocentrum kind. This situation requires a more detailed study of the essential causes of the proliferation of these species.
Open Journal of Marine Science, Volume 10, pp 52-77; doi:10.4236/ojms.2020.102005
Starting from the end of the 90s not perodic and unpredictable variations in the depth of harbor waters were observed. Long period (from 24 hours to a few days) and wide amplitude are their main features. Experience showed that this phenomenon is a risk for harbor navigation and mooring. It may be a serious obstacle to waterside port activities. The first observation of the data does not link the super-highs and the super-dry tides to the meteorological dynamic of sea-atmosphere interaction (i.e. Storm Effect). More, the attempt to compensate for these sea depth fluctuations by means of the well-known offshore hydrobarometric inverse parameter (1 [cm] sea level variation for ǃ [hPa] atmospheric pressure variation) underestimates the amplitude of the phenomenon. In the first years of 2000, the Italian Ministry of Transport launched a national project for the definition of thee-amplitude and time of these tidal anomalous waves. The measure of harbors hydrobarometric inverse factors showed a much more intense value than the theoretical one (computed for the offshore). These amplification factors are characteristic of each harbor and can be double (in exceptional cases even more) than offshore. The delay between the arrival times of these tidal waves (induced phenomenon) respect to the time of arrival of the atmospheric pressure variation (inducing phenomenon) depends on 1) morphology of the port basin sea floor and 2) harbor and off-shre water dynamics relationship (first approximation). For these reasons the hydro barometric inverse parameter is not effectiveness computable but it can be determined statistically.
Open Journal of Marine Science, Volume 10, pp 110-115; doi:10.4236/ojms.2020.103008
Two hundred and forty-three juvenile rainbow trout Oncorhynchus mykiss ranging from 73 to 119 mm were implanted with 8, 9, or 10 mm Passive Integrated Transponder (PIT) tags, with tag retention and fish survival observed for 343 days. Similarly, 173 brown trout Salmo trutta ranging from 71 to 86 mm were implanted with 8 or 10 mm PIT tags and observed for 293 days. Over the entire duration of the study, rainbow trout ejected only six tags, while no tags were ejected from the brown trout. All of the rainbow trout tag ejections occurred before 50 days post-tagging. There was no significant difference in the length or weight of fish that ejected tags compared to those that retained tags. No fish died during the trials. These results indicate that rainbow trout and brown trout at the sizes used in this study can be safely implanted with, and subsequently retain, up to 10 mm PIT tags for durations of nearly one year.
Open Journal of Marine Science, Volume 10, pp 116-130; doi:10.4236/ojms.2020.103009
Underground tunneling is one of the alternative solutions to diminish traffic congestion in large cities. One of the most important effects of tunneling is the displacement of the ground surface, the settlement around the tunnel, and the variation in earthquake acceleration. The performance and behavior of underground structures have been studied by several researchers, but the impact of tunnel excavation on earthquake records and its effects on structures above the ground level have received less attention. This research emphasizes changes of earthquake acceleration at the ground level, structural response and Fourier spectrum by excavating a horseshoe tunnel. Results show that digging a horseshoe tunnel will change the characteristics of the earthquake record at ground level.
Open Journal of Marine Science, Volume 10, pp 141-148; doi:10.4236/ojms.2020.103011
In Terengganu, Longtail tuna or Thunnus tonggol is one of the most popular marine fishes landed by fishermen and has a high demand among customers. This species often served with a unique local delicacy called Nasi Dagang and Ikan Singgang, one of the favourite meals during breakfast by local communities. Since people have always consumed this species, therefore this study aims to identify the consumption rate of this species among Terengganu people. Specifically, this survey data obtained from 124 respondents, ages ranged from 15 to 60 years old from five districts in Terengganu, including Besut, Kuala Nerus, Kuala Terengganu, Hulu Terengganu, and Kemaman. Generally, the estimated amount of this species consumption is 239.7 g per person and 1.83 times per week. From the formula calculated, the amount of this species consumed by one person is 437.4 g/person/week. This value can use to calculate the permissible tolerable weekly intake (PTWI) to estimate the intake of pollutants, such as heavy metals in the human body.
Open Journal of Marine Science, Volume 10, pp 233-244; doi:10.4236/ojms.2020.104018
There has been an increase of community studies that incorporate the use of functional diversity indices. The incorporation of these indices in the analy-sis of marine communities is recent, however, could contribute with relevant information about the health of those communities. The lagoon of La Paz is a body of water located in La Paz, B.C.S., México. Despite its regional im-portance, there are not recent studies about its fish communities. Therefore, the aim of the present study was to analyze the temporal and spatial structure of the functional diversity of fish communities associated to soft bottoms, from August 2016 to July 2017, as well as important environmental varia-bles. Functional diversity indices showed significant differences between months. Spatial analysis did not show significant differences perhaps due to low variability of the type of substrate. Temperature showed temporal dif-ferences as well. Therefore, temperature may be a limiting environmental variable for many fish species inhabiting coastal lagoons.
Open Journal of Marine Science, Volume 10, pp 245-259; doi:10.4236/ojms.2020.104019
The Lom Pangar hydroelectric dam project located in the eastern region of Cameroon was implemented by Electricity Development Corporation (EDC). The impoundment of the Lom Pangar dam created a large reservoir with an area ~590 km2 and a useful storage capacity ~6 billion m3. Thereby, this im-poundment has created favourable conditions for the proliferation of fishery resources. However, a fisheries assessment study based on fishing activities is essential to attain reliable information for implementing a management plan to achieve rational and sustainable exploitation. This study was carried out on the ichtyofaunic inventory and the assessment of fish landings in Lom Pangar hydroelectric dam reservoir from April 2016 to September 30, 2016. Three main groups of fishing gear have been identified, among which gillnets, traps and longlines occupy major fishing activities. Indeed, the spatial and landing sites surveies were conducted on species composition, size composition, and quantities of fish landed during the study period. Moreover, 37 species of fish divided into 16 families were found in seven different selected fish landing sites. Carp (Cyprinus carpio) was the major fish species abundantly caught by these fishing gears which accounted for 81.60% of the total catch, and the least species was sardine (Sardinella aurita). A total of 623,229 Kg of fish were landed which were dominated by those of the Wami landing site with 480,773 Kg representing 76.96% of the total landed catches. The smallest spe-cies caught was the white carp (7 cm) while the longest one was the catfish (71 cm). In addition, the species of fish in the breeding season are carp, catfish, viper fish and red tail.