Next Issue
Volume 10, February
Previous Issue
Volume 9, December
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
3.7
2.9
Journals
JMSE
Volume 10
Issue 1
share announcement

J. Mar. Sci. Eng., Volume 10, Issue 1 (January 2022) – 121 articles

Cover Story (view full-size image): The swimming larva represent the dispersal phase of ascidians, marine invertebrates belonging to tunicates. The anatomy of larva, which reveals the structures that tunicates share with vertebrates, has been described in detail in a few species, showing different degrees of adult structure differentiation, called adultation. By 3D reconstruction, we compared the anatomy of the larva of the solitary ascidian Halocynthia roretzi, a species reared for commercial purpose, with that of two other common species: Ciona intestinalis and Botryllus schlosseri. This approach allowed us to clearly evaluate the different levels of adultation displayed by the diverse species. View this paper
  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Reader to open them.
Order results
Result details
Section
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
18 pages, 4167 KiB  
Article
Strahler Ordering Analyses on Branching Coral Canopies: Stylophora pistillata as a Case Study
by Yaniv Shmuel, Yaron Ziv and Baruch Rinkevich
J. Mar. Sci. Eng. 2022, 10(1), 121; https://doi.org/10.3390/jmse10010121 - 17 Jan 2022
Cited by 4 | Viewed by 3079
Abstract
The three-dimensional structural complexities generated by living sessile organisms, such as trees and branching corals, embrace distinct communities of dwelling organisms, many of which are adapted to specific niches within the structure. Thus, characterizing the build-up rules and the canopy compartments may clarify [...] Read more.
The three-dimensional structural complexities generated by living sessile organisms, such as trees and branching corals, embrace distinct communities of dwelling organisms, many of which are adapted to specific niches within the structure. Thus, characterizing the build-up rules and the canopy compartments may clarify small-scale biodiversity patterns and rules for canopy constituents. While biodiversity within tree canopies is usually typified by the vertical axis that is delineated by its main compartments (understory, trunk, crown), traditional studies of coral canopy dwelling species are evaluated only by viewing the whole coral head as a single homogeneous geometric structure. Here, we employ the Strahler number of a mathematical tree for the numerical measurements of the coral’s canopy complexity. We use the branching Indo-Pacific coral species Stylophora pistillata as a model case, revealing five compartments in the whole coral canopy volume (Understory, Base, Middle, Up, and Bifurcation nods). Then, the coral’s dwellers’ diel distribution patterns were quantified and analyzed. We observed 114 natal colonies, containing 32 dwelling species (11 sessile), totaling 1019 individuals during day observations, and 1359 at night (1–41 individuals/colony). Biodiversity and abundance associated with Strahler numbers, diel richness, abundance, and patterns for compartmental distributions differed significantly between day/night. These results demonstrate that the coral-canopy Strahler number is an applicable new tool for assessing canopy landscapes and canopy associated species biodiversity, including the canopy-compartmental utilization by mobile organisms during day/night and young/adult behaviors. Full article
(This article belongs to the Section Marine Biology)
►▼ Show Figures

Figure 1

48 pages, 8326 KiB  
Article
Investigation on Hydrodynamic Characteristics, Wave–Current Interaction and Sensitivity Analysis of Submarine Hoses Attached to a CALM Buoy
by Chiemela Victor Amaechi, Facheng Wang and Jianqiao Ye
J. Mar. Sci. Eng. 2022, 10(1), 120; https://doi.org/10.3390/jmse10010120 - 17 Jan 2022
Cited by 14 | Viewed by 3353
Abstract
There is an increase in the utilization of the floating offshore structure (FOS) called Catenary Anchor Leg Mooring (CALM) buoys and the attached marine hoses due to the increasing demand for oil and gas products. These hoses are flexible and easier to use [...] Read more.
There is an increase in the utilization of the floating offshore structure (FOS) called Catenary Anchor Leg Mooring (CALM) buoys and the attached marine hoses due to the increasing demand for oil and gas products. These hoses are flexible and easier to use but have a short service life of about 25 years. They are adaptable in ocean locations of shallow, intermediate and deep waters. In this research, a numerical model was developed using a coupling method modeled by utilizing ANSYS AQWA and Orcaflex (Orcina Ltd., Ulverston, UK) dynamic models of the CALM buoy hoses. Two cases were comparatively studied: Lazy-S and Chinese-lantern configurations, under ocean waves and current. Comparisons were also made between coupled and uncoupled models. This research presents the hydrodynamic characteristics with a sensitivity analysis on the influence of waves, current attack angle, soil gradient, soil stiffness and environmental conditions that influence the performance of marine hoses. The study comparatively looked at the configurations from dynamic amplification factors (DAF) on marine hoses. The results show that marine hoses can be easily configured to suit the designer’s need, seabed soil type, seabed topography and the profiles that are useful for manufacturers. The sensitivity analysis also shows the effect of hose parameters on its hydrodynamic behavior from the wave–current interaction (WCI). Full article
(This article belongs to the Special Issue Waves and Ocean Structures II)
►▼ Show Figures

Figure 1

17 pages, 5774 KiB  
Article
Sound Field Fluctuations in Shallow Water in the Presence of Moving Nonlinear Internal Waves
by Yanyu Jiang, Valery Grigorev and Boris Katsnelson
J. Mar. Sci. Eng. 2022, 10(1), 119; https://doi.org/10.3390/jmse10010119 - 17 Jan 2022
Cited by 9 | Viewed by 1622
Abstract
Fluctuations of sound intensity in the presence of moving nonlinear internal waves (NIWs) are studied. Prior works revealed the existence of peaks in the spectrum of these fluctuations due to mode coupling. In the given paper, the results of experiment ASIAEX 2001 are [...] Read more.
Fluctuations of sound intensity in the presence of moving nonlinear internal waves (NIWs) are studied. Prior works revealed the existence of peaks in the spectrum of these fluctuations due to mode coupling. In the given paper, the results of experiment ASIAEX 2001 are considered. Episodes are analyzed when soliton-like NIW move for ~6 h approximately along an acoustic track of length ~30 km. The depth of the ocean changes from ~350 m (position of the source) up to ~120 m near the receiver (Vertical Line Array). The source, placed near the bottom, transmitted pulses (M-sequences) with a frequency of 224 Hz. Theoretical analysis and numerical modeling show that peak frequencies in the spectrum of intensity fluctuations correspond to the most strongly interacting pairs of modes: in the given case pairs 2–3 and 3–4 and values of dominating frequencies are determined by the spatial scale of interference beating Λ of coupling modes and by the speed v of NIW. Due to the fact that in the narrowing channel velocity v decreases as well as the value of Λ, the predominant frequency as a function of time remains approximately the same. Results of modeling are in a good agreement with experimental data. Full article
(This article belongs to the Special Issue Modeling Techniques for Underwater Acoustic Scattering and Propagation (including 3D Effects))
►▼ Show Figures

Figure 1

11 pages, 30663 KiB  
Article
Methods and Proposals for Solutions in the Applicability of a Software-Defined Radio in Maritime Communication
by Miroslav Bistrović and Domagoj Komorčec
J. Mar. Sci. Eng. 2022, 10(1), 118; https://doi.org/10.3390/jmse10010118 - 17 Jan 2022
Cited by 1 | Viewed by 1968
Abstract
Ship communication systems are defined in one part as GMDSS, while the other part consists of systems with secondary importance in safety communications. Each of these devices and systems makes an independent or separate system that works in a specific frequency range and [...] Read more.
Ship communication systems are defined in one part as GMDSS, while the other part consists of systems with secondary importance in safety communications. Each of these devices and systems makes an independent or separate system that works in a specific frequency range and is, at some level, connected to other communication systems. A step forward regarding frequency range and level of networking can be achieved with the application of a software-defined radio. This paper examines a variety of GMDSS communication equipment in terms of technical discrepancy and frequency range. Furthermore, the software-defined radio and SDR configuration development are described according to their theoretical feasibility in the maritime domain. The paper proposes the concept of SDR-based communication systems quite different from conventional maritime communication systems. This approach, conducted in phases, would in turn ease the upgrading, enable flexibility and inter-operation, prolong system life cycle and integrate different maritime communication systems and devices. The proposed concept aims to develop a centralized communication system to incorporate the ship’s communication devices into one common ship communication system. Full article
(This article belongs to the Section Ocean Engineering)
►▼ Show Figures

Figure 1

19 pages, 9629 KiB  
Article
Modular Approach in the Design of Small Passenger Vessels for Mediterranean
by Nikola Vladimir, Andro Bakica, Maja Perčić and Ivana Jovanović
J. Mar. Sci. Eng. 2022, 10(1), 117; https://doi.org/10.3390/jmse10010117 - 17 Jan 2022
Cited by 3 | Viewed by 2401
Abstract
This paper deals with the modular concept in the design of small passenger vessels for the Mediterranean, where the ship is assembled from three virtual modules (hull, power system and superstructure), enabling different vessel characteristics (speed, capacity, environmental performance, habitability, etc.). A set [...] Read more.
This paper deals with the modular concept in the design of small passenger vessels for the Mediterranean, where the ship is assembled from three virtual modules (hull, power system and superstructure), enabling different vessel characteristics (speed, capacity, environmental performance, habitability, etc.). A set of predefined modules is established based on the investigation of market needs, where the IHS Fairplay database is taken as a reference for ship particulars and power needs, while the set of environmental regulation scenarios and requirements on ship habitability are taken as relevant for the design of ship power systems and superstructure modules, respectively. For the selected hull, a series of computations have been conducted to obtain their resistance and power needs which are further satisfied in the above-described manner. Within the illustrative example, a small passenger vessel with a capacity of 250 passengers is considered, with a detailed description of relevant modules that fit future design requirement scenarios. This approach is aimed at small-scale shipyards with limited research capabilities, who can quickly obtain the preliminary design of the vessel which can be further optimized to the final solution. Full article
(This article belongs to the Section Ocean Engineering)
►▼ Show Figures

Figure 1

20 pages, 4786 KiB  
Article
Research on the Water Ridge and Slamming Characteristics of a Semisubmersible Platform under Towing Conditions
by Fali Huo, Changdong Wei, Chenyang Zhu, Zhaojun Yuan and Sheng Xu
J. Mar. Sci. Eng. 2022, 10(1), 116; https://doi.org/10.3390/jmse10010116 - 15 Jan 2022
Cited by 1 | Viewed by 1512
Abstract
During the towing of semisubmersible platforms, waves impact and superpose in front of the platform to form a ridge shaped “water ridge”, which protrudes near the platform and produces a large slamming pressure. The water ridges occur frequently in the towing conditions of [...] Read more.
During the towing of semisubmersible platforms, waves impact and superpose in front of the platform to form a ridge shaped “water ridge”, which protrudes near the platform and produces a large slamming pressure. The water ridges occur frequently in the towing conditions of semisubmersible platforms. The wave–slamming on the braces and columns of platform is aggravated due to the water ridges, particularly in rough sea conditions. The effect of water ridges is usually ignored in slamming pressure analysis, which is used to check the structural strengths of the braces and columns. In this paper, the characteristics of the water ridge at the braces of a semisubmersible platform are studied by experimental tests and numerical simulations. In addition, the sensitivity of the water ridge to the wave height and period is studied. The numerical simulations are conducted by a Computational Fluid Dynamics (CFD) method, and their accuracy is validated based on experimental tests. The characteristics of the water ridge and slamming pressure on the braces and columns are studied in different wave conditions based on the validated numerical model. It is found that the wave extrusion is the main reason of water ridge. The wave–slamming pressure caused by the water ridge has an approximately linear increase with the wave height and is sensitive to the wave period. With the increase of the wave period, the wave–slamming pressure on the brace and column of the platform increases first and then decreases. The maximum wave–slamming pressure is found when the wave period is 10 s and the slamming pressure reduces rapidly with an increase of wave period. Full article
(This article belongs to the Special Issue Ship Motions and Wave Loads)
►▼ Show Figures

Figure 1

24 pages, 10247 KiB  
Article
Research on the Matching Characteristics of the Impellers and Guide Vanes of Seawater Desalination Pumps with High Capacity and Pressure
by Wei Li, Mingjiang Liu, Leilei Ji, Yulu Wang, Muhammad Awais, Jingning Hu and Xiaoyan Ye
J. Mar. Sci. Eng. 2022, 10(1), 115; https://doi.org/10.3390/jmse10010115 - 15 Jan 2022
Cited by 2 | Viewed by 3438
Abstract
This paper presents the matching characteristics of impellers and guide vanes of high capacity and pressure seawater desalination pumps by using computational fluid dynamics (CFD). The single-stage pump is numerically calculated, and its external characteristics are consistent with the test results of model [...] Read more.
This paper presents the matching characteristics of impellers and guide vanes of high capacity and pressure seawater desalination pumps by using computational fluid dynamics (CFD). The single-stage pump is numerically calculated, and its external characteristics are consistent with the test results of model pump. Taking this scheme as a prototype, the research is carried out from three aspects: (i) the impeller blade outlet width; (ii) the number of impeller and guide vane blades; and (iii) the area ratio of impeller outlet to guide vane inlet. The results indicate that the blade outlet width significantly affects the pump head and efficiency. Appropriately increasing the number of guide vane blades or changing the number of impeller blades can improve efficiency and expand the high-efficiency area. Additionally, increasing the throat area of the guide vane has the opposite effect on the large flow and small flow area of the pump. An optimized hydraulic model design scheme is obtained. Full article
(This article belongs to the Section Ocean Engineering)
►▼ Show Figures

Figure 1

13 pages, 1652 KiB  
Article
The Isolation of Vibrio crassostreae and V. cyclitrophicus in Lesser-Spotted Dogfish (Scyliorhinus canicula) Juveniles Reared in a Public Aquarium
by Mattia Tomasoni, Giuseppe Esposito, Davide Mugetti, Paolo Pastorino, Nadia Stoppani, Vasco Menconi, Flavio Gagliardi, Ilaria Corrias, Angela Pira, Pier Luigi Acutis, Alessandro Dondo, Marino Prearo and Silvia Colussi
J. Mar. Sci. Eng. 2022, 10(1), 114; https://doi.org/10.3390/jmse10010114 - 15 Jan 2022
Cited by 5 | Viewed by 2263
Abstract
The genus Vibrio currently contains 147 recognized species widely distributed, including pathogens for aquatic organisms. Vibrio infections in elasmobranchs are poorly reported, often with identifications as Vibrio sp. and without detailed diagnostic insights. The purpose of this paper is the description of the [...] Read more.
The genus Vibrio currently contains 147 recognized species widely distributed, including pathogens for aquatic organisms. Vibrio infections in elasmobranchs are poorly reported, often with identifications as Vibrio sp. and without detailed diagnostic insights. The purpose of this paper is the description of the isolation and identification process of Vibrio spp. following a mortality event of Scyliorhinus canicula juvenile reared in an Italian public aquarium. Following investigations aimed at excluding the presence of different pathogens of marine fish species (parasites, bacteria, Betanodavirus), several colonies were isolated and subjected to species identification using the available diagnostic techniques (a biochemical test, MALDI-TOF MS, and biomolecular analysis). Discrepancies were observed among the methods; the limits of biochemistry as a unique tool for Vibrio species determination were detected through statistical analysis. The use of the rpoB gene, as a diagnostic tool, allowed the identification of the isolates as V. crassostreae and V. cyclotrophicus. Although the pathogenic role of these microorganisms in lesser-spotted dogfish juveniles has not been demonstrated, and the presence of further pathogens cannot be excluded, this study allowed the isolation of two Vibrio species in less-studied aquatic organisms, highlighting the weaknesses and strengths of the different diagnostic methods applied. Full article
(This article belongs to the Special Issue Microbial Diseases of Marine Organisms)
►▼ Show Figures

Figure 1

26 pages, 12759 KiB  
Article
CFD Simulation and Experimental Study on Coupled Motion Response of Ship with Tank in Beam Waves
by Tao He, Dakui Feng, Liwei Liu, Xianzhou Wang and Hua Jiang
J. Mar. Sci. Eng. 2022, 10(1), 113; https://doi.org/10.3390/jmse10010113 - 14 Jan 2022
Cited by 11 | Viewed by 2199
Abstract
Tank sloshing is widely present in many engineering fields, especially in the field of marine. Due to the trend of large-scale liquid cargo ships, it is of great significance to study the coupled motion response of ships with tanks in beam waves. In [...] Read more.
Tank sloshing is widely present in many engineering fields, especially in the field of marine. Due to the trend of large-scale liquid cargo ships, it is of great significance to study the coupled motion response of ships with tanks in beam waves. In this study, the CFD (Computational Fluid Dynamics) method and experiments are used to study the response of a ship with/without a tank in beam waves. All the computations are performed by an in-house CFD solver, which is used to solve RANS (Reynold Average Navier-Stokes) equations coupled with six degrees-of-freedom solid-body motion equations. The Level Set Method is used to solve the free surface. Verification work on the grid number and time step size has been conducted. The simulation results agree with the experimental results well, which shows that the numerical method is accurate enough. In this paper, several different working conditions are set up, and the effects of the liquid height in the tank, the size of the tank and the wavelength ratio of the incident wave on the ship’s motion are studied. The results show the effect of tank sloshing on the ship’s motion in different working conditions. Full article
(This article belongs to the Special Issue Ship Motions and Wave Loads)
►▼ Show Figures

Figure 1

19 pages, 1661 KiB  
Review
Anomaly Detection in Maritime AIS Tracks: A Review of Recent Approaches
by Konrad Wolsing, Linus Roepert, Jan Bauer and Klaus Wehrle
J. Mar. Sci. Eng. 2022, 10(1), 112; https://doi.org/10.3390/jmse10010112 - 14 Jan 2022
Cited by 34 | Viewed by 8090
Abstract
The automatic identification system (AIS) was introduced in the maritime domain to increase the safety of sea traffic. AIS messages are transmitted as broadcasts to nearby ships and contain, among others, information about the identification, position, speed, and course of the sending vessels. [...] Read more.
The automatic identification system (AIS) was introduced in the maritime domain to increase the safety of sea traffic. AIS messages are transmitted as broadcasts to nearby ships and contain, among others, information about the identification, position, speed, and course of the sending vessels. AIS can thus serve as a tool to avoid collisions and increase onboard situational awareness. In recent years, AIS has been utilized in more and more applications since it enables worldwide surveillance of virtually any larger vessel and has the potential to greatly support vessel traffic services and collision risk assessment. Anomalies in AIS tracks can indicate events that are relevant in terms of safety and also security. With a plethora of accessible AIS data nowadays, there is a growing need for the automatic detection of anomalous AIS data. In this paper, we survey 44 research articles on anomaly detection of maritime AIS tracks. We identify the tackled AIS anomaly types, assess their potential use cases, and closely examine the landscape of recent AIS anomaly research as well as their limitations. Full article
(This article belongs to the Special Issue Risk Assessment and Traffic Behaviour Evaluation of Ships)
►▼ Show Figures

Figure 1

13 pages, 4708 KiB  
Article
Pore-Scale Investigation of the Electrical Property and Saturation Exponent of Archie’s Law in Hydrate-Bearing Sediments
by Jinhuan Zhao, Changling Liu, Chengfeng Li, Yongchao Zhang, Qingtao Bu, Nengyou Wu, Yang Liu and Qiang Chen
J. Mar. Sci. Eng. 2022, 10(1), 111; https://doi.org/10.3390/jmse10010111 - 14 Jan 2022
Cited by 14 | Viewed by 1662
Abstract
Characterizing the electrical property of hydrate-bearing sediments is essential for hydrate reservoir identification and saturation evaluation. As the major contributor to electrical conductivity, pore water is a key factor in characterizing the electrical properties of hydrate-bearing sediments. The objective of this study is [...] Read more.
Characterizing the electrical property of hydrate-bearing sediments is essential for hydrate reservoir identification and saturation evaluation. As the major contributor to electrical conductivity, pore water is a key factor in characterizing the electrical properties of hydrate-bearing sediments. The objective of this study is to clarify the effect of hydrates on pore water and the relationship between pore water characteristics and the saturation exponent of Archie’s law in hydrate-bearing sediments. A combination of X-ray computed tomography and resistivity measurement technology is used to derive the three-dimensional spatial structure and resistivity of hydrate-bearing sediments simultaneously, which is helpful to characterize pore water and investigate the saturation exponent of Archie’s law at the micro-scale. The results show that the resistivity of hydrate-bearing sediments is controlled by changes in pore water distribution and connectivity caused by hydrate formation. With the increase of hydrate saturation, pore water connectivity decreases, but the average coordination number and tortuosity increase due to much smaller and more tortuous throats of pore water divided by hydrate particles. It is also found that the saturation exponent of Archie’s law is controlled by the distribution and connectivity of pore water. As the parameters of connected pore water (e.g., porosity, water saturation) decrease, the saturation exponent decreases. At a low hydrate-saturation stage, the saturation exponent of Archie’s law changes obviously due to the complicated pore structure of hydrate-bearing sediments. A new logarithmic relationship between the saturation exponent of Archie’s law and the tortuosity of pore water is proposed which helps to calculate field hydrate saturation using resistivity logging data. Full article
(This article belongs to the Special Issue Marine Gas Hydrate: Geological Characterization, Resource Potential, Exploration and Development)
►▼ Show Figures

Figure 1

14 pages, 2568 KiB  
Article
The Role of Soil Structure Interaction in the Fragility Assessment of HP/HT Unburied Subsea Pipelines
by Davide Forcellini, Daniele Mina and Hassan Karampour
J. Mar. Sci. Eng. 2022, 10(1), 110; https://doi.org/10.3390/jmse10010110 - 14 Jan 2022
Cited by 3 | Viewed by 1533
Abstract
Subsea high pressure/high temperature (HP/HT) pipelines may be significantly affected by the effects of soil structure interaction (SSI) when subjected to earthquakes. Numerical simulations are herein applied to assess the role of soil deformability on the seismic vulnerability of an unburied pipeline. Overcoming [...] Read more.
Subsea high pressure/high temperature (HP/HT) pipelines may be significantly affected by the effects of soil structure interaction (SSI) when subjected to earthquakes. Numerical simulations are herein applied to assess the role of soil deformability on the seismic vulnerability of an unburied pipeline. Overcoming most of the contributions existing in the literature, this paper proposes a comprehensive 3D model of the system (soil + pipeline) by performing OpenSees that allows the representation of non-linear mechanisms of the soil and may realistically assess the induced damage caused by the mutual interaction of buckling and seismic loads. Analytical fragility curves are herein derived to evaluate the role of soil structure interaction in the assessment of the vulnerability of a benchmark HP/HT unburied subsea pipeline. The probability of exceeding selected limit states was based on the definition of credited failure criteria. Full article
(This article belongs to the Special Issue Subsea System Design)
►▼ Show Figures

Figure 1

16 pages, 31344 KiB  
Article
Control of Reactive Oxygen Species through Antioxidant Enzymes Plays a Pivotal Role during the Cultivation of Neopyropia yezoensis
by Zezhong Feng, Lingjuan Wu, Zhenjie Sun, Jiali Yang, Guiyan Liu, Jianfeng Niu and Guangce Wang
J. Mar. Sci. Eng. 2022, 10(1), 109; https://doi.org/10.3390/jmse10010109 - 14 Jan 2022
Cited by 6 | Viewed by 1591
Abstract
Neopyropia yezoensis is an economically important marine crop that can survive dehydrating conditions when nets are lifted from seawater. During this process, production of oxygen radicals and the resulting up-regulation of antioxidant enzymes mediated by the abscisic acid (ABA) signaling pathway played an [...] Read more.
Neopyropia yezoensis is an economically important marine crop that can survive dehydrating conditions when nets are lifted from seawater. During this process, production of oxygen radicals and the resulting up-regulation of antioxidant enzymes mediated by the abscisic acid (ABA) signaling pathway played an important role. However, there were no reports about the significance regarding the protection of seaweed throughout the entire production season. Especially, in new aquatic farms in Shandong Province that were formed when traditional N. yezoensis cultivation moved north. Here, we determined the levels of ABA, hydrogen peroxide (H2O2), soluble protein, chlorophyll, and cell wall polysaccharides in samples collected at different harvest periods from Jimo aquatic farm, Shandong Province. The activities and expression of NADPH oxidase (NOX) and antioxidant enzymes in the corresponding samples were also determined. Combined with the monitoring data of sea surface temperature and solar light intensity, we proposed that the cultivation of N. yezoensis in Shandong Province was not affected by high-temperature stress. However, photoinhibition in N. yezoensis usually occurs at noon, especially in March. Both the activities and the expression of NOX and antioxidant enzymes were up-regulated continuously. It is reasonable to speculate that the reactive oxygen species (ROS) produced by NOX induced the up-regulation of antioxidant enzymes through the ABA signaling pathway. Although antioxidant enzymes play a pivotal role during the cultivation of N. yezoensis, the production of ROS also caused a shift in gene expression, accumulation of secondary metabolites, and even decreased the chlorophyll pool size, which eventually led to a decrease in algae assimilation. Accordingly, we suggest that the dehydration of N. yezoensis nets should be adopted when necessary and the extent of dehydration should be paid special consideration to avoid an excessive cellular response caused by ROS. Full article
(This article belongs to the Special Issue Algal Cultivation and Breeding)
►▼ Show Figures

Figure 1

20 pages, 5823 KiB  
Article
Influence Mechanism of Geomorphological Evolution in a Tidal Lagoon with Rising Sea Level
by Cuiping Kuang, Jiadong Fan, Zhichao Dong, Qingping Zou, Xin Cong and Xuejian Han
J. Mar. Sci. Eng. 2022, 10(1), 108; https://doi.org/10.3390/jmse10010108 - 14 Jan 2022
Cited by 3 | Viewed by 1313
Abstract
A tidal lagoon system has multiple environmental, societal, and economic implications. To investigate the mechanism of influence of the geomorphological evolution of a tidal lagoon, the effect of critical erosion shear stress, critical deposition shear stress, sediment settling velocity, and initial bed elevation [...] Read more.
A tidal lagoon system has multiple environmental, societal, and economic implications. To investigate the mechanism of influence of the geomorphological evolution of a tidal lagoon, the effect of critical erosion shear stress, critical deposition shear stress, sediment settling velocity, and initial bed elevation were assessed by applying the MIKE hydro- and morpho-dynamic model to a typical tidal lagoon, Qilihai Lagoon. According to the simulation results, without sediment supply, an increase of critical erosion, deposition shear stress, or sediment settling velocity gives rise to tidal networks with a stable terrain. Such an equilibrium state can be defined as when the change of net erosion has little variation, which can be achieved due to counter actions between the erosion and deposition effect. Moreover, the influence of the initial bed elevation depends on the lowest tidal level. When the initial bed elevation is below the lowest tidal level, the tidal networks tend to be fully developed. A Spearman correlation analysis indicated that the geomorphological evolution is more sensitive to critical erosion or deposition shear stress than sediment settling velocity and initial bed elevation. Exponential sea level rise contributes to more intensive erosion than the linear or the parabolic sea level rise in the long-term evolution of a tidal lagoon. Full article
(This article belongs to the Section Coastal Engineering)
►▼ Show Figures

Figure 1

30 pages, 1168 KiB  
Article
Towards a Cyber-Physical Range for the Integrated Navigation System (INS)
by Aybars Oruc, Vasileios Gkioulos and Sokratis Katsikas
J. Mar. Sci. Eng. 2022, 10(1), 107; https://doi.org/10.3390/jmse10010107 - 14 Jan 2022
Cited by 7 | Viewed by 4200
Abstract
The e-navigation concept was introduced by the IMO to enhance berth-to-berth navigation towards enhancing environmental protection, and safety and security at sea by leveraging technological advancements. Even though a number of e-navigation testbeds including some recognized by the IALA exist, they pertain to [...] Read more.
The e-navigation concept was introduced by the IMO to enhance berth-to-berth navigation towards enhancing environmental protection, and safety and security at sea by leveraging technological advancements. Even though a number of e-navigation testbeds including some recognized by the IALA exist, they pertain to parts only of the Integrated Navigation System (INS) concept. Moreover, existing e-navigation and bridge testbeds do not have a cybersecurity testing functionality, therefore they cannot be used for assessing the cybersecurity posture of the INS. With cybersecurity concerns on the rise in the maritime domain, it is important to provide such capability. In this paper we review existing bridge testbeds, IMO regulations, and international standards, to first define a reference architecture for the INS and then to develop design specifications for an INS Cyber-Physical Range, i.e., an INS testbed with cybersecurity testing functionality. Full article
(This article belongs to the Section Ocean Engineering)
►▼ Show Figures

Figure 1

16 pages, 8743 KiB  
Article
Three-Dimensional Simulations of Scour around Pipelines of Finite Lengths
by Dongfang Liang, Jie Huang, Jingxin Zhang, Shujing Shi, Nichenggong Zhu and Jun Chen
J. Mar. Sci. Eng. 2022, 10(1), 106; https://doi.org/10.3390/jmse10010106 - 14 Jan 2022
Cited by 7 | Viewed by 1777
Abstract
In the past few decades, there have been many numerical studies on the scour around offshore pipelines, most of which concern two-dimensional setups, with the pipeline infinitely long and the flow perpendicular to the pipeline. Based on the Ansys FLUENT flow solver, this [...] Read more.
In the past few decades, there have been many numerical studies on the scour around offshore pipelines, most of which concern two-dimensional setups, with the pipeline infinitely long and the flow perpendicular to the pipeline. Based on the Ansys FLUENT flow solver, this study establishes a numerical tool to study the three-dimensional scour around pipelines of finite lengths. The user-defined functions are written to calculate the sediment transport rate, update the bed elevation, and adapt the computational mesh to the new boundary. The correctness of the model has been verified against the measurements of the conventional two-dimensional scour around a long pipe and the three-dimensional scour around a sphere. A series of computations are subsequently carried out to discover how the scour hole is dependent on the pipeline length. It is found that the equilibrium scour depth increases with the pipeline length until the pipeline length exceeds four times the pipe diameter. Full article
(This article belongs to the Special Issue Instability and Failure of Subsea Structures)
►▼ Show Figures

Figure 1

4 pages, 199 KiB  
Editorial
Taxonomy and Ecology of Marine Algae
by Bum Soo Park and Zhun Li
J. Mar. Sci. Eng. 2022, 10(1), 105; https://doi.org/10.3390/jmse10010105 - 14 Jan 2022
Cited by 1 | Viewed by 1852
Abstract
The term “algae” refers to a large diversity of unrelated phylogenetic entities, ranging from picoplanktonic cells to macroalgal kelps [...] Full article
(This article belongs to the Special Issue Taxonomy and Ecology of Marine Algae)
12 pages, 4774 KiB  
Article
Variation of Internal Tides on the Continental Slope of the Southeastern East China Sea
by Bing Yang, Po Hu and Yijun Hou
J. Mar. Sci. Eng. 2022, 10(1), 104; https://doi.org/10.3390/jmse10010104 - 14 Jan 2022
Cited by 1 | Viewed by 1581
Abstract
The semidiurnal internal tides (ITs) on the continental slope of the southeastern East China Sea (ECS) exhibited abrupt enhancement in November of 2017. This enhancement resulted from the intensification of the coherent semidiurnal ITs. Coherent and incoherent semidiurnal ITs had a comparative energy [...] Read more.
The semidiurnal internal tides (ITs) on the continental slope of the southeastern East China Sea (ECS) exhibited abrupt enhancement in November of 2017. This enhancement resulted from the intensification of the coherent semidiurnal ITs. Coherent and incoherent semidiurnal ITs had a comparative energy contribution in October; however, coherent semidiurnal ITs dominated with a variance contribution of 90% in November. The variance contribution of vertical modes of the semidiurnal ITs varied between October and November, and the mode with most variance contribution changed from the second mode to the first mode. Altimeter data and the observed background currents indicated that the Kuroshio mainstream meandered and abruptly intruded into the ECS in November. The upper layer background currents were significantly related to the kinetic energy of the semidiurnal ITs, and the correlation coefficient between them reached 0.81. The frequent occurrences of the Kuroshio intrusion have suggested that the ITs in the ECS are susceptible to the modulation of the Kuroshio current. Numerical modeling and predication of ITs should consider the meander of the Kuroshio mainstream. Full article
(This article belongs to the Section Physical Oceanography)
►▼ Show Figures

Figure 1

14 pages, 22018 KiB  
Article
Study on the Vortex in a Pump Sump and Its Influence on the Pump Unit
by Xijie Song, Chao Liu and Zhengwei Wang
J. Mar. Sci. Eng. 2022, 10(1), 103; https://doi.org/10.3390/jmse10010103 - 13 Jan 2022
Cited by 5 | Viewed by 1888
Abstract
The vortex in a pump sump is a negative problem for the pump unit, which can lead to the decline of pump performance. Focusing on the internal pressure characteristics of the floor-attached vortex (FAV) and its influence on the pump unit, the FAV [...] Read more.
The vortex in a pump sump is a negative problem for the pump unit, which can lead to the decline of pump performance. Focusing on the internal pressure characteristics of the floor-attached vortex (FAV) and its influence on the pump unit, the FAV was analyzed adopting the previously verified numerical simulation method and experiment. The results show that the pressure in the vortex core gradually decreases with time, drops to a negative pressure at the development stage, and then reaches the lowest pressure during the continuance stage. When the negative pressure of the vortex tube is around the vaporization pressure of the continuance stage, it can cause a local cavitation at the impeller inlet. The evolution of the FAV is accompanied by a change of pressure gradient in the vortex core which is discussed in detail. This research provides theoretical guidance for a better understanding of the vortex characteristics and the optimal design for the pump. Full article
(This article belongs to the Section Ocean Engineering)
►▼ Show Figures

Figure 1

17 pages, 14979 KiB  
Article
Methods for Fitting the Limit State Function of the Residual Strength of Damaged Ships
by Zhiyao Zhu, Huilong Ren, Xiuhuan Wang, Nan Zhao and Chenfeng Li
J. Mar. Sci. Eng. 2022, 10(1), 102; https://doi.org/10.3390/jmse10010102 - 13 Jan 2022
Cited by 1 | Viewed by 1197
Abstract
The limit state function is important for the assessment of the longitudinal strength of damaged ships under combined bending moments in severe waves. As the limit state function cannot be obtained directly, the common approach is to calculate the results for the residual [...] Read more.
The limit state function is important for the assessment of the longitudinal strength of damaged ships under combined bending moments in severe waves. As the limit state function cannot be obtained directly, the common approach is to calculate the results for the residual strength and approximate the limit state function by fitting, for which various methods have been proposed. In this study, four commonly used fitting methods are investigated: namely, the least-squares method, the moving least-squares method, the radial basis function neural network method, and the weighted piecewise fitting method. These fitting methods are adopted to fit the limit state functions of four typically sample distribution models as well as a damaged tanker and damaged bulk carrier. The residual strength of a damaged ship is obtained by an improved Smith method that accounts for the rotation of the neutral axis. Analysis of the results shows the accuracy of the linear least-squares method and nonlinear least-squares method, which are most commonly used by researchers, is relatively poor, while the weighted piecewise fitting method is the better choice for all investigated combined-bending conditions. Full article
(This article belongs to the Special Issue Ship Structures)
►▼ Show Figures

Figure 1

22 pages, 6833 KiB  
Article
Bathymetric Survey of the St. Anthony Channel (Croatia) Using Multibeam Echosounders (MBES)—A New Methodological Semi-Automatic Approach of Point Cloud Post-Processing
by Ante Šiljeg, Ivan Marić, Fran Domazetović, Neven Cukrov, Marin Lovrić and Lovre Panđa
J. Mar. Sci. Eng. 2022, 10(1), 101; https://doi.org/10.3390/jmse10010101 - 13 Jan 2022
Cited by 11 | Viewed by 3242
Abstract
Multibeam echosounders (MBES) have become a valuable tool for underwater floor mapping. However, MBES data are often loaded with different measurement errors. This study presents a new user-friendly and methodological semi-automatic approach of point cloud post-processing error removal. The St. Anthony Channel (Croatia) [...] Read more.
Multibeam echosounders (MBES) have become a valuable tool for underwater floor mapping. However, MBES data are often loaded with different measurement errors. This study presents a new user-friendly and methodological semi-automatic approach of point cloud post-processing error removal. The St. Anthony Channel (Croatia) was selected as the research area because it is regarded as one of the most demanding sea or river passages in the world and it is protected as a significant landscape by the Šibenik-Knin County. The two main objectives of this study, conducted within the Interreg Italy–Croatia PEPSEA project, were to: (a) propose a methodological framework that would enable the easier and user-friendly identification and removal of the errors in MBES data; (b) create a high-resolution integral model (MBES and UAV data) of the St. Anthony Channel for maritime safety and tourism promotion purposes. A hydrographic survey of the channel was carried out using WASSP S3 MBES while UAV photogrammetry was performed using Matrice 210 RTK V2. The proposed semi-automatic post-processing of the MBES acquired point cloud was completed in the Open Source CloudCompare software following five steps in which various point filtering methods were used. The reduction percentage in points after the denoising process was 14.11%. Our results provided: (a) a new user-friendly methodological framework for MBES point filtering; (b) a detailed bathymetric map of the St. Anthony Channel with a spatial resolution of 50 cm; and (c) the first integral (MBES and UAV) high-resolution model of the St. Anthony Channel. The generated models can primarily be used for maritime safety and tourism promotion purposes. In future research, ground-truthing methods (e.g., ROVs) will be used to validate the generated models. Full article
(This article belongs to the Section Coastal Engineering)
►▼ Show Figures

Figure 1

23 pages, 21053 KiB  
Article
Late Quaternary Marine Terraces and Tectonic Uplift Rates of the Broader Neapolis Area (SE Peloponnese, Greece)
by Efthimios Karymbalis, Konstantinos Tsanakas, Ioannis Tsodoulos, Kalliopi Gaki-Papanastassiou, Dimitrios Papanastassiou, Dimitrios-Vasileios Batzakis and Konstantinos Stamoulis
J. Mar. Sci. Eng. 2022, 10(1), 99; https://doi.org/10.3390/jmse10010099 - 12 Jan 2022
Cited by 6 | Viewed by 3295
Abstract
Marine terraces are geomorphic markers largely used to estimate past sea-level positions and surface deformation rates in studies focused on climate and tectonic processes worldwide. This paper aims to investigate the role of tectonic processes in the late Quaternary evolution of the coastal [...] Read more.
Marine terraces are geomorphic markers largely used to estimate past sea-level positions and surface deformation rates in studies focused on climate and tectonic processes worldwide. This paper aims to investigate the role of tectonic processes in the late Quaternary evolution of the coastal landscape of the broader Neapolis area by assessing long-term vertical deformation rates. To document and estimate coastal uplift, marine terraces are used in conjunction with Optically Stimulated Luminescence (OSL) dating and correlation to late Quaternary eustatic sea-level variations. The study area is located in SE Peloponnese in a tectonically active region. Geodynamic processes in the area are related to the active subduction of the African lithosphere beneath the Eurasian plate. A series of 10 well preserved uplifted marine terraces with inner edges ranging in elevation from 8 ± 2 m to 192 ± 2 m above m.s.l. have been documented, indicating a significant coastal uplift of the study area. Marine terraces have been identified and mapped using topographic maps (at a scale of 1:5000), aerial photographs, and a 2 m resolution Digital Elevation Model (DEM), supported by extensive field observations. OSL dating of selected samples from two of the terraces allowed us to correlate them with late Pleistocene Marine Isotope Stage (MIS) sea-level highstands and to estimate the long-term uplift rate. Based on the findings of the above approach, a long-term uplift rate of 0.36 ± 0.11 mm a−1 over the last 401 ± 10 ka has been suggested for the study area. The spatially uniform uplift of the broader Neapolis area is driven by the active subduction of the African lithosphere beneath the Eurasian plate since the study area is situated very close (~90 km) to the active margin of the Hellenic subduction zone. Full article
(This article belongs to the Special Issue Tectonics and Sea-Level Fluctuations)
►▼ Show Figures

Figure 1

12 pages, 1249 KiB  
Article
Current Dependent Dispersal Characteristics of Japanese Glass Eel around Taiwan
by Kuan-Mei Hsiung, Yen-Ting Lin and Yu-San Han
J. Mar. Sci. Eng. 2022, 10(1), 98; https://doi.org/10.3390/jmse10010098 - 12 Jan 2022
Cited by 4 | Viewed by 1810
Abstract
Japanese eel larvae are passively transported to the East Asian Continental Shelf by the North Equatorial Current, Kuroshio and Kuroshio intrusion currents, and coastal currents. Previous studies have investigated the dispersal characteristics and pathways of Japanese glass eels. However, there are still limitations [...] Read more.
Japanese eel larvae are passively transported to the East Asian Continental Shelf by the North Equatorial Current, Kuroshio and Kuroshio intrusion currents, and coastal currents. Previous studies have investigated the dispersal characteristics and pathways of Japanese glass eels. However, there are still limitations in these studies. According to long-term (2010–2020) catch data from the Fisheries Agency in Taiwan, the distribution and time series of glass eels recruitment to Taiwan are closely related to the surrounding ocean currents. Recruitment begins in eastern Taiwan via the mainstream Kuroshio and in southern Taiwan via the Taiwan Strait Warm Current. In central Taiwan, recruitment occurs from southern Taiwan, as well as from mainland China via the southern branch of the China Coast Current (CCC). The latest recruitment occurred in northern Taiwan and mainly comprised glass eels from mainland China via the northern branch of the CCC. A stronger monsoon during the La Niña phase could affect the recruitment time series in northern and eastern Taiwan. This study suggests that the recruitment directionality of glass eels is an indicator of the flow field of ocean/coastal currents and elucidates the dispersal characteristics of glass eels in the waters around Taiwan. Full article
(This article belongs to the Special Issue Interannual Variation of Planktonic Species and Fish Populations)
►▼ Show Figures

Figure 1

23 pages, 18444 KiB  
Article
Seasonal and Long-Term Variability of Coccolithophores in the Black Sea According to Remote Sensing Data and the Results of Field Investigations
by Sergey V. Vostokov, Anastasia S. Vostokova and Svetlana V. Vazyulya
J. Mar. Sci. Eng. 2022, 10(1), 97; https://doi.org/10.3390/jmse10010097 - 12 Jan 2022
Cited by 9 | Viewed by 1734
Abstract
Based on satellite data from the SeaWiFS, MODIS-Aqua, and MODIS-Terra scanners, the long-term dynamics of coccolithophores in the Black Sea and their large-scale heterogeneity have been studied. During the twenty years in May and June, mass development of coccolithophores population of different intensities [...] Read more.
Based on satellite data from the SeaWiFS, MODIS-Aqua, and MODIS-Terra scanners, the long-term dynamics of coccolithophores in the Black Sea and their large-scale heterogeneity have been studied. During the twenty years in May and June, mass development of coccolithophores population of different intensities was recorded annually. Summer blooms of coccolithophores reached peak levels in 2006, 2012, and 2017, after abnormally cold winters. It was noted that in conditions of low summer temperatures, the blooming of coccolithophores could be significantly reduced or acquire a local character (2004). In the anomalous cold summer of 2001, coccolithophore blooms was replaced by the mass growth of diatoms. Over twenty years, numerous signs of coccolithophores mass development in the cold season have been revealed. Winter blooms develop mainly in warm winters with periods of low wind activity. The formation of a thermocline and the surface layer’s stability are essential factors for initiating winter blooms of coccolithophores. It was noted that after the winter blooms of coccolithophores, their summer growth was poorly expressed. It is shown that during periods of rapid growth, the bulk of coccolithophores is concentrated in the upper mixed layer and thermocline. During the blooming period, the share of coccolithophores in phytoplankton biomass constituted 70–85%. The intensity of coccolithophore’s blooms is associated with the previous diatoms’ growth level. The effect of eddies circulation on the distribution and growth of coccolithophores is considered. Full article
(This article belongs to the Special Issue Long-term Phytoplankton Dynamics in Ecosystem)
►▼ Show Figures

Figure 1

17 pages, 2505 KiB  
Article
Dietary Agaricus blazei Spent Substrate Improves Disease Resistance of Nile Tilapia (Oreochromis niloticus) against Streptococcus agalactiae In Vivo
by Po-Tsang Lee, Yu-Sheng Wu, Chung-Chih Tseng, Jia-Yu Lu and Meng-Chou Lee
J. Mar. Sci. Eng. 2022, 10(1), 100; https://doi.org/10.3390/jmse10010100 - 12 Jan 2022
Cited by 4 | Viewed by 1849
Abstract
This study evaluated the effects of the feeding of spent mushroom substrate from Agaricus blazei on Nile tilapia (Oreochromis niloticus). The safety of 0–1000 μg/mL A. blazei spent substrate water extract (ABSSE) was demonstrated in the primary hepatic and splenic macrophages [...] Read more.
This study evaluated the effects of the feeding of spent mushroom substrate from Agaricus blazei on Nile tilapia (Oreochromis niloticus). The safety of 0–1000 μg/mL A. blazei spent substrate water extract (ABSSE) was demonstrated in the primary hepatic and splenic macrophages and the THK cell line (a cell line with characteristics of melanomacrophages) using a cytotoxicity assay. Here, 10 μg/mL of crude ABSSE promoted the phagocytic activity of macrophages and THK cells. Stimulating ABSSE-primed THK cells with lipopolysaccharides or peptidoglycan resulted in higher expression levels of four cytokine genes (e.g., interleukinz (IL)-1β, IL-12b, IL-8 and tumor necrosis factor α (TNFα)) and one cytokine gene (TNFα), respectively. An in vitro bacterial growth inhibition assay demonstrated that ABSSE could inhibit the growth of Streptococcus agalactiae. In the first feeding trial, Nile tilapia were fed with experimental feed containing 0, 1, or 5% of A. blazei spent substrate (ABSS) for seven and fourteen days followed by bacterial challenge assay. The best result was obtained when Nile tilapia were continuously fed for seven days on a diet containing 1% ABSS, with the survival rate being higher than in groups with 0% and 5% ABSS after challenge with S. agalactiae. In the second trial, fish were fed diets supplemented with 0% or 1% ABSS for seven days, and then all the groups were given the control feed for several days prior to bacterial challenge in order to investigate the duration of the protective effect provided by ABSS. The results showed that the protective effects were sustained at day 7 after the feed was switched. Overall, spent mushroom substrate from A. blazei is a cost-effective feed additive for Nile tilapia that protects fish from S. agalactiae infection. Full article
(This article belongs to the Special Issue Nutrition and Immunity for Sustainable Marine Aquaculture Development)
►▼ Show Figures

Figure 1

20 pages, 3448 KiB  
Review
Review of Top-Down Method to Determine Atmospheric Emissions in Port. Case of Study: Port of Veracruz, Mexico
by Gilberto Fuentes García, Rodolfo Sosa Echeverría, José María Baldasano Recio, Jonathan D. W. Kahl and Rafael Esteban Antonio Durán
J. Mar. Sci. Eng. 2022, 10(1), 96; https://doi.org/10.3390/jmse10010096 - 11 Jan 2022
Cited by 8 | Viewed by 2253
Abstract
Indicators of environmental policies in force in Mexico, fossil fuels will continue to be used in industrial sectors, especially marine fuels, such as marine diesel oil, in port systems for some time. Considering this, we have evaluated several methods corresponding to a top-down [...] Read more.
Indicators of environmental policies in force in Mexico, fossil fuels will continue to be used in industrial sectors, especially marine fuels, such as marine diesel oil, in port systems for some time. Considering this, we have evaluated several methods corresponding to a top-down system for determining fuel consumption and sulfur dioxide atmospheric emissions for the port of Veracruz in 2020 by type of ship on a daily resolution, considering a sulfur content of 0.5% mass by mass in marine fuel. After analyzing seven methods for determining sulfur dioxide atmospheric emission levels, Goldsworthy’s method was found to be the best option to characterize this port. The port system has two maritime zones, one of which is in expansion, which represented 55.66% of fuel consumption and 23.05% of atmospheric emissions according to the typology of vessels. We found that higher fuel consumption corresponded to container vessels, and tanker vessels represented higher atmospheric emission levels in the berthing position. The main differences that we found in the analysis of the seven methods of the top-down system corresponded to the load factor parameter, main and auxiliary engine power, and estimation of fuel consumption by type of vessel. Full article
(This article belongs to the Special Issue Water Pollution under Climate Change in Coastal Areas)
►▼ Show Figures

Figure 1

15 pages, 2657 KiB  
Article
Shoreline Detection Accuracy from Video Monitoring Systems
by Jaime Arriaga, Gabriela Medellin, Elena Ojeda and Paulo Salles
J. Mar. Sci. Eng. 2022, 10(1), 95; https://doi.org/10.3390/jmse10010095 - 11 Jan 2022
Cited by 4 | Viewed by 1884
Abstract
Video monitoring has become an indispensable tool to understand beach processes. However, the measurement accuracy derived from the images has been taken for granted despite its dependence on the calibration process and camera movements. An easy to implement self-fed image stabilization algorithm is [...] Read more.
Video monitoring has become an indispensable tool to understand beach processes. However, the measurement accuracy derived from the images has been taken for granted despite its dependence on the calibration process and camera movements. An easy to implement self-fed image stabilization algorithm is proposed to solve the camera movements. Georeferenced images were generated from the stabilized images using only one calibration. To assess the performance of the stabilization algorithm, a second set of georeferenced images was created from unstabilized images following the accepted practice of using several calibrations. Shorelines were extracted from the images and corrected with the measured water level and the computed run-up to the 0 m contour. Image-derived corrected shorelines were validated with one hundred beach profile surveys measured during a period of four years along a 1.1 km beach stretch. The simultaneous high-frequency field data available of images and beach surveys are uncommon and allow assessing seasonal changes and long-term trends accuracy. Errors in shoreline position do not increase in time suggesting that the proposed stabilization algorithm does not propagate errors, despite the ever-evolving vegetation in the images. The image stabilization reduces the error in shoreline position by 40 percent, having a larger impact with increasing distance from the camera. Furthermore, the algorithm improves the accuracy on long-term trends by one degree of magnitude (0.01 m/year vs. 0.25 m/year). Full article
(This article belongs to the Special Issue Dynamics in Coastal Areas)
►▼ Show Figures

Figure 1

38 pages, 859 KiB  
Review
A Review of Modeling Approaches for Understanding and Monitoring the Environmental Effects of Marine Renewable Energy
by Kate E. Buenau, Lysel Garavelli, Lenaïg G. Hemery and Gabriel García Medina
J. Mar. Sci. Eng. 2022, 10(1), 94; https://doi.org/10.3390/jmse10010094 - 11 Jan 2022
Cited by 10 | Viewed by 4090
Abstract
Understanding the environmental effects of marine energy (ME) devices is fundamental for their sustainable development and efficient regulation. However, measuring effects is difficult given the limited number of operational devices currently deployed. Numerical modeling is a powerful tool for estimating environmental effects and [...] Read more.
Understanding the environmental effects of marine energy (ME) devices is fundamental for their sustainable development and efficient regulation. However, measuring effects is difficult given the limited number of operational devices currently deployed. Numerical modeling is a powerful tool for estimating environmental effects and quantifying risks. It is most effective when informed by empirical data and coordinated with the development and implementation of monitoring protocols. We reviewed modeling techniques and information needs for six environmental stressor–receptor interactions related to ME: changes in oceanographic systems, underwater noise, electromagnetic fields (EMFs), changes in habitat, collision risk, and displacement of marine animals. This review considers the effects of tidal, wave, and ocean current energy converters. We summarized the availability and maturity of models for each stressor–receptor interaction and provide examples involving ME devices when available and analogous examples otherwise. Models for oceanographic systems and underwater noise were widely available and sometimes applied to ME, but need validation in real-world settings. Many methods are available for modeling habitat change and displacement of marine animals, but few examples related to ME exist. Models of collision risk and species response to EMFs are still in stages of theory development and need more observational data, particularly about species behavior near devices, to be effective. We conclude by synthesizing model status, commonalities between models, and overlapping monitoring needs that can be exploited to develop a coordinated and efficient set of protocols for predicting and monitoring the environmental effects of ME. Full article
(This article belongs to the Special Issue Technology and Methods for Environmental Monitoring of Marine Renewable Energy)
►▼ Show Figures

Figure 1

8 pages, 1165 KiB  
Article
Simultaneous Determination of Fluorine and Chlorine in Marine and Stream Sediment by Ion Chromatography Combined with Alkaline Digestion in a Bomb
by Yuhua Gao, Xiaoyuan Wang, Xianwen Fang, Xuebo Yin, Lu Chen, Jianling Bi, Yao Ma and Shuai Chen
J. Mar. Sci. Eng. 2022, 10(1), 93; https://doi.org/10.3390/jmse10010093 - 11 Jan 2022
Cited by 2 | Viewed by 1897
Abstract
Fluorine and chlorine are important tracers for geochemical and environmental studies. In this study, a rapid alkaline digestion (NaOH) method for the simultaneous determination of fluorine and chlorine in marine and stream sediment reference samples using ion chromatography is developed. The proposed method [...] Read more.
Fluorine and chlorine are important tracers for geochemical and environmental studies. In this study, a rapid alkaline digestion (NaOH) method for the simultaneous determination of fluorine and chlorine in marine and stream sediment reference samples using ion chromatography is developed. The proposed method suppresses the volatilization loss of fluorine and chlorine and decreases the matrix effects. The results are in good agreement with fluorine ~100%, chlorine ranging from 90 to 95% of the expected concentrations. The detection limits of this method were 0.05 μg/g for fluorine and 0.10 μg/g for chlorine. This method is simple, economical, precise and accurate, which shows great potential for the rapid simultaneous determination of fluorine and chlorine in large batches of geological and environmental samples commonly analyzed for environmental geochemistry studies. Full article
(This article belongs to the Special Issue Research on Submarine Hydrothermal Activity and Its Material Circulation, Magmatic Setting, and Seawater, Sedimentary, Biologic Effects)
►▼ Show Figures

Figure 1

41 pages, 1762 KiB  
Article
What’s in My Toolkit? A Review of Technologies for Assessing Changes in Habitats Caused by Marine Energy Development
by Lenaïg G. Hemery, Kailan F. Mackereth and Levy G. Tugade
J. Mar. Sci. Eng. 2022, 10(1), 92; https://doi.org/10.3390/jmse10010092 - 11 Jan 2022
Cited by 5 | Viewed by 3043
Abstract
Marine energy devices are installed in highly dynamic environments and have the potential to affect the benthic and pelagic habitats around them. Regulatory bodies often require baseline characterization and/or post-installation monitoring to determine whether changes in these habitats are being observed. However, a [...] Read more.
Marine energy devices are installed in highly dynamic environments and have the potential to affect the benthic and pelagic habitats around them. Regulatory bodies often require baseline characterization and/or post-installation monitoring to determine whether changes in these habitats are being observed. However, a great diversity of technologies is available for surveying and sampling marine habitats, and selecting the most suitable instrument to identify and measure changes in habitats at marine energy sites can become a daunting task. We conducted a thorough review of journal articles, survey reports, and grey literature to extract information about the technologies used, the data collection and processing methods, and the performance and effectiveness of these instruments. We examined documents related to marine energy development, offshore wind farms, oil and gas offshore sites, and other marine industries around the world over the last 20 years. A total of 120 different technologies were identified across six main habitat categories: seafloor, sediment, infauna, epifauna, pelagic, and biofouling. The technologies were organized into 12 broad technology classes: acoustic, corer, dredge, grab, hook and line, net and trawl, plate, remote sensing, scrape samples, trap, visual, and others. Visual was the most common and the most diverse technology class, with applications across all six habitat categories. Technologies and sampling methods that are designed for working efficiently in energetic environments have greater success at marine energy sites. In addition, sampling designs and statistical analyses should be carefully thought through to identify differences in faunal assemblages and spatiotemporal changes in habitats. Full article
(This article belongs to the Special Issue Technology and Methods for Environmental Monitoring of Marine Renewable Energy)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-121
Previous Issue
Next Issue
Back to TopTop