海洋科学期刊(英文)最新文献

{"title":"Utilizing Occupancy Models and Platforms-of-Opportunity to Assess Area Use of Mother-Calf Humpback Whales","authors":"J. Currie, S. Stack, Jessica A. McCordic, J. Roberts","doi":"10.4236/OJMS.2018.82014","DOIUrl":"https://doi.org/10.4236/OJMS.2018.82014","url":null,"abstract":"The Hawaiian Islands, and particularly the Maui 4-island region, are a critical breeding and calving habitat for humpback whales (Megaptera novaeangliae) belonging to the Hawaii distinct population segment. Our aims were to test the use of platforms-of-opportunity to determine trends in mother-calf pod use of the region and to present opportunistic platforms as an alternative method of long-term, cross-seasonal monitoring. Data were collected from whale watching vessels over a 4-year period and analyzed using occupancy models to determine the probability of habitat use of pods with calves and pods without calves within the study area. Detection probability was influenced by survey effort and month for all pod types with detection of adult only pods further influenced by year. Pods with a calf showed a preference for shallow ( 75 meters). Results presented here align with previous work, both in Hawaii and in other breeding grounds, which show a distinct segregation of mothers with a calf from other age-classes of humpback whales. The need for long-term continuous monitoring of cetacean populations is crucial to ensure species conservation. Data collected aboard platforms-of-opportunity, as presented here, provide important insight on humpback whale spatial and temporal distribution, which are essential for species protection and management.","PeriodicalId":65849,"journal":{"name":"海洋科学期刊(英文)","volume":"08 1","pages":"276-292"},"PeriodicalIF":0.0,"publicationDate":"2018-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47763066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Occurrence and Distribution of Marsh Clam, Polymesoda spp. in Marudu Bay, Sabah, Malaysia","authors":"J. Ransangan, T. K. Soon","doi":"10.4236/ojms.2018.82017","DOIUrl":"https://doi.org/10.4236/ojms.2018.82017","url":null,"abstract":"Marudu Bay is part of the Tun Mustapha Marine Park, the largest marine protected area within the Malaysian region of the Coral Triangle Initiative. The bay is known for its diversed fisheries resources including bivalves. Although some of these bivalve species are commercially important, their occurrence, distribution and stock status in the bay are not well documented. Hence, the current study was conducted to determine the occurrence, distribution and the stock status of marsh clam, Polymerasoda spp. in the mangrove swamp situated at the southernmost of the Marudu Bay. Samplings were carried out at the mangrove swamps which covered an area of 500 sequare meter per sampling site. Two marsh clams species, Polymesoda erosa and P. expansa were found to inhabit the sampling sites. In general, juvenile marsh clams were noticed to dominate the seaward mangrove swamp, whereas the high tidal regions were dominated by adults. The current study also suggested a link in the distribution and the morphometric measurements of the marsh clams with the sediment grain size.","PeriodicalId":65849,"journal":{"name":"海洋科学期刊(英文)","volume":"08 1","pages":"314-322"},"PeriodicalIF":0.0,"publicationDate":"2018-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46057869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of Zooplankton Species Structure and Dominance in Anzali International Wetland","authors":"Delaram Golmarvi, M. F. Kapourchali, A. Moradi, M. Fatemi, R. M. Nadoshan","doi":"10.4236/OJMS.2018.82011","DOIUrl":"https://doi.org/10.4236/OJMS.2018.82011","url":null,"abstract":"Anzali International wetland is one of the most important places for various \u0000organisms such as fishes. Zooplankton are the first consumers in the ecosystem, \u0000and they are perfect food for the larvae of fishes. The present study conducted \u0000monthly during January 2012 to December 2013 in 9 different stations \u0000with zooplankton population and chemical characteristics analysis such as \u0000water temperature ranged from 10°C - 22°C, pH determined alkaline nature \u0000of the wetland ranged from 7.05 to 9.47, dissolved oxygen was recorded in the \u0000range of 3.36 mg/l to 10.51 mg/l, nitrate was ranged between 0.48 - 4.36 mg/l, \u0000total phosphates was between 0.15 - 0.67 mg/l, salinity was recorded between \u0000220 - 692 mg/l, TDS was determined between 246 - 1971 mg/l, BOD \u0000and COD was also recorded 2 - 36 mg/l and 4 - 74 mg/l respectively. Total 61 \u0000zooplankton species were found belonging to 4 groups: Protozoa (22 sp.), Rotatoria \u0000(29 sp.), Copepoda (5 sp.) and Cladocera (4 sp.). Rotatoria were found \u0000dominating other groups of zooplankton. Kruskal Wallis test showed that \u0000there was significant difference between density of zooplankton in different \u0000stations, months and seasons (P ≤ 0.05) and significant differences were found \u0000between densities of different zooplankton phylum (P ≤ 0.05). The water body \u0000is continuously receiving domestic discharge leading to large amount of nutrient \u0000inputs and high amount of phosphate and nitrate in the water body indicates \u0000that water is eutrophic in nature.","PeriodicalId":65849,"journal":{"name":"海洋科学期刊(英文)","volume":"08 1","pages":"215-222"},"PeriodicalIF":0.0,"publicationDate":"2018-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44675131","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Conservative Model for Nonlinear Dynamics in a Stratified, Rotating Fluid","authors":"N. Filatoff, X. Carton","doi":"10.4236/ojms.2018.82013","DOIUrl":"https://doi.org/10.4236/ojms.2018.82013","url":null,"abstract":"We present a set of equations describing the nonlinear dynamics of flows constrained by environmental rotation and stratification (Rossby numbers Ro∈[0.1,0.5] and Burger numbers of order unity). The fluid is assumed incompressible, adiabatic, inviscid and in hydrostatic balance. This set of equations is derived from the Navier Stokes equations (with the above properties), using a Rossby number expansion with second order truncation. The resulting model has the following properties: 1) it can represent motions with moderate Rossby numbers and a Burger number of order unity; 2) it filters inertia-gravity waves by assuming that the divergence of horizontal velocity remains small; 3) it is written in terms of a single function of space and time (pressure, generalized streamfunction or Bernoulli function); 4) it conserves total (Ertel) vorticity in a Lagrangian form, and its quadratic norm (potential enstrophy) at the model order in Rossby number; 5) it also conserves total energy at the same order if the work of pressure forces vanishes when integrated over the fluid domain. The layerwise version of the model is finally presented, written in terms of pressure. Integral properties (energy, enstrophy) are conserved by these layerwise equations. The model equations agree with the generalized geostrophy equations in the appropriate parameter regime. Application to vortex dynamics are mentioned.","PeriodicalId":65849,"journal":{"name":"海洋科学期刊(英文)","volume":"08 1","pages":"253-275"},"PeriodicalIF":0.0,"publicationDate":"2018-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41322389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Demographics and Population Dynamics Project the Future of Hard Coral Assemblages in Little Cayman","authors":"K. Foster, G. Foster","doi":"10.4236/ojms.2018.81010","DOIUrl":"https://doi.org/10.4236/ojms.2018.81010","url":null,"abstract":"Individual hard coral colonies from four representative reef sites around Little \u0000Cayman were surveyed yearly between 2010 and 2015, a period of non-disturbance \u0000between two elevated seawater temperature anomalies. Photographic \u0000censuses produced 7069 annual transitions that were used to describe the demographics \u0000(size class frequencies, abundance, area cover) and population \u0000dynamics under non-disturbance environmental conditions. Agariciids, Porites \u0000asteroides, and Siderastrea radians have replaced acroporids as the predominant \u0000massive corals. Recruitment rates were generally low (2), except for a fourfold recruitment pulse of S. radians that occurred in \u00002011. On average, 42% of coral recruits survived their first year but only 10% \u0000lived longer than four years. Temporal comparisons allowed correction factors \u0000to be calculated for in-situ methods that overestimate recruitment of colonies \u0000≤2 cm in diameter and overlook larger colonies. Size class transitions \u0000included growth (~33%), stasis (~33%), partial mortality (10% - 33%), and \u0000whole colony mortality, which decreased with increasing colony size (typically \u000030 cm2). Transition matrices indicated \u0000that Little Cayman assemblages have declining hard coral populations (λ 150 cm2 surface areas, live area cover may remain relatively \u0000stable. Projection models indicated that downward population trends would \u0000be exacerbated even by mild disturbance (5% - 10% mortality) scenarios. The \u0000fate of hard corals on Little Cayman’s reefs was determined to be heavily dependent \u0000on the health and transitions of agariciid colonies. Conservation \u0000strategies that currently focus on restoration of Caribbean acroporids should \u0000be expanded to include agariciids, which were previously considered “weeds”.","PeriodicalId":65849,"journal":{"name":"海洋科学期刊(英文)","volume":"08 1","pages":"196-213"},"PeriodicalIF":0.0,"publicationDate":"2018-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42049825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chondrichthyes Chitinase: Molecular Cloning, Distribution, and Phylogenetic Analysis","authors":"Miku Watanabe, H. Kakizaki, M. Kanai, S. Kawashima, K. Hamaguchi, Hiroki Mizuno, T. Ueno, Chiaki Yasukawa, Ryuji Agata, Mana Ikeda, H. Fukushima, M. Ueda, M. Matsumiya","doi":"10.4236/OJMS.2018.81007","DOIUrl":"https://doi.org/10.4236/OJMS.2018.81007","url":null,"abstract":"We have previously reported the presence of three types of chitinase (acidic fish chitinase-1: AFCase-1, acidic fish chitinase-2: AFCase-2, fish chitinase-3: FCase-3) in Actinopterygii. In the present research, we report the identification of the novel chitinase genes HjChi (ORF: 1380 bp) and DkChi (ORF: 1440 bp) from the stomach of Chondrichthyes, Japanese bullhead shark (Heterodontus japonicas) and Kwangtung skate (Dipturus kwangtungensis), respectively. Organ-specific expression analysis identified the stomach-specific expression of HjChi, whereas DkChi was expressed widely in all organs. Chitinase activity was measured using pNP-(GlcNAc)n (n = 2, 3) as a substrate and β-N-acetylhexosaminidase (Hex) activity was measured using pNPGlcNAc. Relatively high values of chitinase activity were observed in the stomach, spleen, and gonads of the Japanese bullhead shark, H. japonicas , compared with that observed in the stomach of the Kwangtung skate D. kwangtungensis . However, Hex activity was detected throughout the body of both species. The optimal pH of chitinase in both the Japanese bullhead shark, H. japonicas, and the Kwangtung skate, D. kwangtungensis, were 3.5 - 5.5 and 3.5 - 4.0, respectively, and 4.0 for Hex in both species. Phylogenetic analysis revealed that Chondrichthyes chitinase forms a unique group (Chondrichthyes chitinase). These results suggested that the possibility of the formation of chitinase groups for each class in the phylogenetic analysis based on the observation of class-specific chitinase.","PeriodicalId":65849,"journal":{"name":"海洋科学期刊(英文)","volume":"08 1","pages":"136-151"},"PeriodicalIF":0.0,"publicationDate":"2018-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42290750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Lateral Eddy Viscosity Derived from the Decay of Oceanic Mesoscale Eddies","authors":"Qiuyang Li, Liang Sun, Chi Xu","doi":"10.4236/OJMS.2018.81008","DOIUrl":"https://doi.org/10.4236/OJMS.2018.81008","url":null,"abstract":"The relationship of lateral eddy viscosity depending on length scale is estimated with the decay rate of mesoscale eddies identified from sea level anomaly of satellite observations. The eddy viscosity is expressed in terms of the mesoscale eddy parameters according to vortex dynamics. The census of mesoscale eddies shows, in general, that the eddy numbers obey the e-folding decay laws in terms of their amplitude, area and lifetime. The intrinsic values in the e-folding laws are used to estimate the lateral eddy viscosity. Dislike the previous theory that diffusivities are proportional to the length square, the eddy mixing rates (diffusivity and viscosity) from satellite mesoscale eddy datasets are proportional to rs to power of 1.8 (slightly less than 2), where rs is the radius of eddy with radius larger than the Batchelor scale. Additionally, the extrapolation of the eddy mixing to the molecule scale implies that the above power laws may hold until the value of rs is less than O (1 m). These mixing rates with the new parameterizations are suggested to use in numerical schemes. Finally, the climatological distributions of eddy viscosity are calculated.","PeriodicalId":65849,"journal":{"name":"海洋科学期刊(英文)","volume":"08 1","pages":"152-172"},"PeriodicalIF":0.0,"publicationDate":"2018-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41645864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distribution of Gastropods in the Intertidal Environment of South, Middle and North Andaman Islands, India","authors":"C. Jeeva, P. Mohan, K. Sabith, Vibha V. Ubare, M. Muruganantham, Radha Karuna Kumari","doi":"10.4236/OJMS.2018.81009","DOIUrl":"https://doi.org/10.4236/OJMS.2018.81009","url":null,"abstract":"Andaman and Nicobar Islands, the gastropod diversity is high, due to the \u0000majority of shores are rocky. The wet rocky shore promotes algal growth, \u0000which is ultimate for feeding ground for gastropod growth and development \u0000leading to more diversity. The global warming, anthropogenic activities, industrial \u0000and domestic pollution, etc., have accelerated the loss of coastal and \u0000marine biodiversity components over the last few decades which has been of \u0000great concern. However, except global warming, the other factors were of least \u0000concern with reference to Andaman and Nicobar Islands biodiversity due to a \u0000pristine environment. Therefore, exploration of biodiversity in these islands is \u0000essential to create a baseline data for record and future research. Four locations \u0000of south to north Andaman Islands which represented Carbyns Cove \u0000from south Andaman, Rangat and Mayabunder from the Middle Andaman \u0000and Diglipur from the North Andaman were selected for this study. Gastropoda \u0000species were collected for a period of one year in three prevailing seasons \u0000of Andaman and Nicobar Islands. They are South West Monsoon (SW monsoon), \u0000North East Monsoon (NE Monsoon) and Non Rainy Seasons (NR Seasons). \u0000The present study of gastropods distribution in the South, Middle and \u0000North Andaman groups of Islands suggested that there are 71 species belonging \u0000to 52 genus and 33 families. At any one of the time and any one of the locations, \u0000only one occurrence was noticed for 38 species and remaining 33 species \u0000were overlapping with respect to stations and seasons. Evaluation of the \u0000cluster suggested that Cluster A (NR season in Carbyns Cove) and Cluster B \u0000(NE and SW Monsoon in Mayabunder) as a separate entity among the 12 \u0000combinations of stations and seasons due to their species representation. It was also concluded that out of 71 studied species, 3 species were not reported \u0000till date in these Island environment and 2 species from any other parts of India.","PeriodicalId":65849,"journal":{"name":"海洋科学期刊(英文)","volume":"08 1","pages":"173-195"},"PeriodicalIF":0.0,"publicationDate":"2018-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44301734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of Marine Pollution of Ports and Jetties in Rivers State, Nigeria","authors":"S. Nitonye, Ofanson Uyi","doi":"10.4236/ojms.2018.81006","DOIUrl":"https://doi.org/10.4236/ojms.2018.81006","url":null,"abstract":"Ports and jetties complex operations come with various forms of pollutions. The analysis of marine pollution from ports becomes very necessary and complicated due to the various types of pollution, sources, effects and different characteristics. The sources of environmental pollution other than ships and from industrial activities in port and jetties were critically looked at and analyzed. A complete review of the environmental pollution in ports and the tools to assess and minimize such negative environmental impact are analyzed. The instrument of questionnaires was employed and distributed among two seaports and one jetty; Onne, Okrika and Port Harcourt to collect respondents’ opinions on effects, sources and causes of marine pollution. The chi-square test for independence was used with 180 respondents from Onne port, Port Harcourt port and Okrika jetty. Water sample was collected from Onne seaport and pollution contents such as total petroleum hydrocarbon (TPH), bio-chemical oxygen demand (BOD), turbidity, pH and salinity were tested in the laboratory. The result shows that Onne water had a salinity level of 20,790 (mg/l) which under the salinity range of water is considered saline, a turbidity level of 4.00 (NTU) which was considered average comparing with a 5.00 (NTU) bench mark, BOD5 level of 0.48 (mg/l) which was considered pristine because most pristine seawater will have BOD below 1 (mg/l), pH level of 7.77 which falls under the range of sea water being alkaline (7.2 - 8.4), TPH level of 2.98 (mg/l) since all conditions of sampling and sample preservations were observed and the value is less than the DPR limit (10 mg/l). It was concluded that the activities in Onne port are within the acceptable limits. It was also observed from the questionnaire that a larger population of respondents in Onne, Okrika and Port Harcourt ports where conscious of the sources and effects of environmental pollution from their respective ports.","PeriodicalId":65849,"journal":{"name":"海洋科学期刊(英文)","volume":"08 1","pages":"114-135"},"PeriodicalIF":0.0,"publicationDate":"2018-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46029055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatial and Temporal Baseline Information on Marine Megafauna-Data Facilitated by a Wildlife Tour Operator","authors":"M. D. Boer, Duncan Jones, Hannah F. E. Jones, Rebecca Knee","doi":"10.4236/OJMS.2018.81005","DOIUrl":"https://doi.org/10.4236/OJMS.2018.81005","url":null,"abstract":"The protection of marine megafauna within Europe is rather fragmented. Developing conservation measures for highly mobile species presents definite challenges, particularly due to the many knowledge gaps. Recent studies have shown that these gaps can be filled in by Platforms of Opportunity (PO) which create low-cost approaches. However, the number of wildlife tour operators actively collecting PO data related to distribution and relative abundance of marine fauna remains limited. In this study, we investigated whether effort-corrected data on marine megafauna facilitated by a wildlife tour operator afforded robust long temporal data (2011-2015). Sightings data, collected in the wider Mount’s Bay area (southwest Cornwall, UK), along with a GPS application, were collected to accurately record survey effort. In addition, radial sighting distances and detection curves were computed to explore the robustness of the data. Density maps of marine megafauna indicated that encounters occurred throughout the area in all three seasons but the temporal distribution was significantly different with numbers peaking in autumn. Odontocetes were mostly recorded during autumn, basking shark (Cetorhinus maximus) and ocean sunfish (Mola mola) were more abundant during summer and leatherback turtles (Dermochelys coriacea) were recorded occasionally. Our data showed that this shallow coastal environment is particularly important as a nursing area for harbour porpoises (Phocoena phocoena). Risso’s dolphins (Grampus griseus) showed a high semi-residency pattern for adults with calves within one core-habitat. As such, the study provides important spatial and temporal baseline data that are essential for the protection of marine megafauna through the development of an ecological network of marine protected areas within UK waters. Although, data facilitated by wildlife operators have certain shortcomings we highlight that the protocols developed here secured efficient and precise data. Such collection protocols can be implemented on a larger scale, ultimately enhancing research monitoring efforts and marine ecosystem management.","PeriodicalId":65849,"journal":{"name":"海洋科学期刊(英文)","volume":"08 1","pages":"76-113"},"PeriodicalIF":0.0,"publicationDate":"2018-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47069053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}