Finkl, C.W. and Makowski, C., 2022. Identification of domain complexes in the Danube Delta Coastal Belt using the Biophysical Cross-shore Classification System (BCCS), based on interpretation of satellite imagery. Journal of Coastal Research, 38(1), 1–18. Coconut Creek (Florida), ISSN 0749-0208.

The Biophysical Cross-shore Classification System (BCCS) was applied to the Danube Delta on the NW margin of the Black Sea to ascertain whether this method of classification was applicable to extensive low-lying and low-relief wetland coastalscapes. For organizational purposes, the coastal belt study area was broken into four previously recognized delta lobes (Kilia, Sulina, St. George II, and Cosna–Sinoie) and the Chituc Formation (beach ridge plain) because these provided distinctive coastal segments that were manageable for cross-shore classification. The village of Prymors'ke in the Lyman municipality of Ukraine and the onshore Chituc Formation beach ridge strandplain on the southern margin of the delta marked the northern- and southernmost extents of the Danubian classification effort, respectively. Codified cross-shore catenary sequences were based on the occurrence of recurring archetypes (i.e. Barrier, Beach, Beach Ridge, Delta, Developed, Lagoon, and Wetland) that had alongshore extent and could be identified as domains. Sub archetypes were also interpreted and added to the cross-shore sequences to further refine the Danube Delta classification. Because long cross-shore catenary sequences included inland biophysical and anthropogenic units that often differed dramatically from immediate onshore features, the conflated catenas were bifurcated into onshore (seaward) and inland (landward) domains, sections, or branches that were collectively referred to as domain complexes. Extension of cross-shore transects up to 20 km inland to incorporate all salient aspects of the delta provided useful subdivision of delta landscapes. Sixteen cross-shore transects were used to derive 12 domain complexes extending 167.5 km along the Danubian coastal belt that reached from the approximate latitudes of Prymors'ke, Ukraine, in the north to about Corbu in Romania to the south. Classification of the Danube Delta coastal belts showed that it is possible to apply the BCCS to large-area delta regions using extended cross-shore transects with bifurcated catenary sequences that together describe seaward (onshore) and landward (inland) sections of the delta in the form of domain complexes.

Sutherland, T.F.; Amos, C.L., and Grant, J., 2022. The resuspension and deposition of biomediated sediments in Upper South Cove, Nova Scotia, Canada. Journal of Coastal Research, 38(1), 19–34. Coconut Creek (Florida), ISSN 0749-0208.

Coastal seabed sediment stability is mediated by microalgal and bacterial biofilms. The resuspension of organic suspended particulate matter (SPM) in biomediated sediments increases nutrient fluxes to the water column and supplements particulate food supplies for suspension feeders. Thus, quantifying benthic-pelagic exchange pathways of biogeochemical parameters is essential to provide an accurate assessment of carrying capacities of coastal embayments supporting both natural and cultured bivalve populations. Benthic-pelagic transport coefficients such as erosion threshold (U_{*CRIT-SPM-EROSION}), net erosion rate (NER_SPM), peak erosion rate (PER_SPM), depositional threshold (U_{*CRIT-SPM-DEPOSITION}), and deposition rate (DR_SPM) were determined using an in situ benthic flume (Sea Carousel) in the protected inner termination of Upper South Cove (USC). The layered gel-like muddy seabed consisted of a thin biofilm or flocculated material overlying highly reduced black sediments. Eroded material was analyzed for concentrations of SPM, chlorophyll-a (CHL), phaeopigment (PHA), and organic/inorganic content. All stations exhibited a consistent pattern of staggered erosion thresholds of seabed constituents, where U_*CRIT-SPM > U_*CRIT-PHA > U_*CRIT-CHL. Erosion thresholds of these sediment constituents were inversely related to NER_SPM, NER_CHL, and NER_PHA fluxes as part of a principal component analysis. U_{*CRIT-SPM-EROSION} was generally higher than U_{*CRIT-SPM-DEPOSITION} across the individual USC stations, suggesting that SPM deposition largely occurs before erosion. A tight coupling was observed between both the mean NER_SPM (1.37×10^–3 kg m^–2 s^–1) and DR_SPM (1.23×10^–3 kg m^–2 s^–1) and the occurrence frequency between erosion (44.2%) and deposition (52.5%) phases derived from a 4-day U* time-series profile. Although these results highlight a tight benthic-pelagic coupling system in USC, some overlap appears to occur between the deposition and erosion phases, which can be attributed to the presence of diverse SPM size classes that alter during erosion (shearing) and velocity deceleration (floc-forming) processes. Benthic-pelagic coupling supports the sustained near-bottom turbidity conditions observed in USC.

Oo, Y.H.; Zhang, H., and Colleter, G., 2022. Nearshore wave simulations and wave characteristics analysis during extreme weather events. Journal of Coastal Research, 38(1), 35–51. Coconut Creek (Florida), ISSN 0749-0208.

Offshore storm wave direction may distinguish between an extreme event and a typical event experienced at nearshore. Using a state-of-the-art spectral wave (SW) model, the purposes of this study are: (1) to investigate the transformation of waves from offshore to nearshore along the coastline from two opposite directions (northerly and southerly); and (2) to analyse the offshore wave energy density spectrum. The SW model was calibrated considering various mesh resolutions and lateral wind forcing with different wind field resolutions. The results show that a longshore wave attenuation gradient exists from the southerly swell, primarily due to different degrees of sheltering provided by the headland. In contrast, the coast essentially becomes an open coast from northerly swells, thereby producing a significant reduction in wave attenuation. The wave energy density spectrum indicates that wave pattern varies depending on offshore wave direction. Both storms produce a wide range of frequencies and directions. However, southerly swells only produce single-peaked spectrum, while double-peaked spectrum is observed in northerly swells due to the presence of prevailing swells and storm swells. This study highlights the significant reduction of wave attenuation when predominate offshore wave direction is abrupted.

Hopkins, M.; Lopez, J., and Songy, A., 2022. Coastal subsidence due to faults: Insights from elevation profiles of vehicular bridges, southeastern Louisiana, U.S.A. Journal of Coastal Research, 38(1), 52–65. Coconut Creek (Florida), ISSN 0749-0208.

Normal faults are common geological structures in the Mississippi River Delta within the underlying thick Cenozoic sedimentary section. Some faults have been identified as active, have deformed artificial features in the past century, and are concurrent with Louisiana's massive loss of coastal wetlands. Subsidence due to vertical motion, or slip, on faults, however, is poorly understood spatially and over decadal to centennial timescales. Therefore, how faults contribute to subsidence and subsequent land loss over these timescales must be considered for coastal wetland restoration efforts. Here, the elevation profiles of seven vehicular bridges that cross five known faults were analyzed to investigate the spatial and temporal behavior of the faults. Bridge elevation profiles are an effective method to analyze these faults over the timescale of interest for several reasons: (1) the bridges are of known age (10–89 y), (2) they were initially constructed horizontally, and (3) they are constructed on a foundation anchored below compacting Holocene sediments. Faults were projected to the surface using subsurface data such as seismic reflection data and well logs, and abrupt vertical offsets in the elevation of the bridges near a known fault are the result of slip. Four of the five faults examined show an offset in the bridges that cross them, and the offsets are largest at the traces. Offset rates, which are interpreted to be fault-slip rates, were calculated utilizing bridge age and the total offset amounts at the traces. Slip rates range from 0.6 ± 0.06 mm/y to 3.2 ± 0.2 mm/y. Restoration project viability may face significant risks from fault-related subsidence. The biggest threat appears to be limited spatially to within hundreds of meters of the faults, however, that risk cannot be totally precluded at greater distances from the faults.

Ortiz Royero, J.C.; Henriquez Cera, S., and Gomes, H., 2022. Coastal meteo-marine parameters of Hurricane Matthew along the Colombian Caribbean coast: Establishing a baseline of knowledge. Journal of Coastal Research, 38(1), 66–76. Coconut Creek (Florida), ISSN 0749-0208.

The hurricanes on the Colombian continental coast have been lower in intensity and number than in other areas of the Caribbean Sea. Thus, given the lack of knowledge about the hurricane parameters in this area, the protocols to deal with a hurricane emergency on the Columbian continental coast are not clear. This work analyzes the meteo-marine parameters caused in Colombia by the passage of Hurricane Matthew to establish a baseline of knowledge. Further progress in understanding the effects the hurricane may have had on several coastal areas, particularly in the areas of hydrology, morphological changes, storm surge, and flood, is expected in future work. The results show that the most significant meteo-marine parameter was the swell generated by the hurricane; although it followed a NW trajectory toward the coast, the swell reached up to 4.5 m of significant wave height and a peak period of 14 seconds. Also, the accumulated rainfall in only 3 days significantly exceeded the average monthly values of October (the rainiest month of the year). This effect is of particular interest given that recent modeling studies established an increase in precipitation rates associated with tropical hurricanes. The wind was not significant with respect to typical values in the zone.

Ding, Z.; Zhang, Y.; Wang, Y., and Zhao, Q., 2022. Determining the structural frame damage mechanisms of deep-sea manned submersibles. Journal of Coastal Research, 38(1), 77–85. Coconut Creek (Florida), ISSN 0749-0208.

Deployment and recovery data describing the service life of the Jiaolong-manned submersible and its structural frame damage inspection records suggest that the damage sustained by the structural frame could be related to wave loads when the manned submersible is recovered in rough seas. The computational fluid dynamics simulation was used to calculate the wave loads acting on the manned submersible in this article, and the results were used as inputs for a finite element analysis of the structural frame to evaluate the stress in and displacement of the structural frame during manned submersible recovery in rough seas. The results of this analysis indicated that some of the nodes in the structural frame experienced stresses considerably in excess of the permitted limits and approached the yield strength of the material, representing a severe threat to the safety of the Jiaolong-manned submersible when recovered in rough seas.

Wolny, J.L.; McCollough, C.B.; Rosales, D.S., and Pitula, J.S., 2022. Harmful algal bloom species in the St. Martin River: Surveying the headwaters of northern Maryland's coastal bays. Journal of Coastal Research, 38(1), 86–98. Coconut Creek (Florida), ISSN 0749-0208.

In the spring seasons of 2015 through 2017, the Maryland Department of Natural Resources and the University of Maryland Eastern Shore monitored the phytoplankton community of the headwaters of the St. Martin River, a tributary at the northern end of Maryland's coastal bays, to determine the presence and extent of harmful algal bloom (HAB) species. The phytoplankton community composition, including HAB species, was examined via weekly sampling from March through June. In 2015, HAB events began in late March with a bloom of Gymnodinium aureolum, representing the first report of this species in Maryland waters. Following the G. aureolum bloom, blooms of other HAB species occurred, including Dinophysis acuminata, Karlodinium veneficum, Prorocentrum minimum, and a species in the Alexandrium minutum complex. Initiating at the NW extent of the St. Martin River, these blooms became distributed both temporally and spatially throughout the study area. These same species were detected in 2016 and 2017 but at lower concentrations than those seen in 2015. High concentrations and diverse blooms of HAB species in 2015 may have been due to significant rain events and/or an increase in ammonium levels from a legacy nutrient pool following the removal of the Bishopville Dam, located upstream of the study site in November 2014. This study provides a baseline assessment for future work on harmful algae in the St. Martin River watershed and a look into phytoplankton community dynamics after a dam removal.

Fernandez, P.N.J., 2022. Using a low-cost green light emitting diode to measure total suspended solids in a marine protected area of the Philippines. Journal of Coastal Research, 38(1), 99–113. Coconut Creek (Florida), ISSN 0749-0208.

Seawater parameters are important indicators of coastal water conditions. One of the essential parameters is the total suspended solids (TSS). This study probed how to use a low-cost 535-nm green LED to measure the TSS in marine protected areas of barangay Lo-ong, Concepcion, Iloilo, Philippines. It aims to examine the relationship of the total attenuation coefficients (TAC) to total suspended solids (TSS) values in coastal water. Sample sea waters were taken from various locations and brought to a laboratory for a filtration process known as gravimetry. Different available filter paper sizes (1.5 microns, 6 microns, 20 microns, and 50 microns) were used in the filtration process and were dried in a controlled constant temperature of 110 degrees Celsius for 24 hours using an electric oven. Dried filter papers' weights were measured using an analytical balance before using the infiltration of seawater. TAC values were also measured in different seawater samples using a prototype device made up of LED and photodiode. This study demonstrated that TAC values of green LEDs are positively correlated with TSS values (R value of 0.45). Results reveal that the moderate correlation between an LED's TAC values to TSS positively proved that a low-cost LED can be used as an alternative to the more expensive remote sensing satellite data. Findings of the study also showed that TSS values in the marine protected area under study were far below the acceptable limits for coastal waters. The performance of the LED-based measuring device can still be improved in the future by using collimating lenses and more sensitive photomultiplier tubes.

Chen, L.; Zhai, H.; Wang, P.; Zhang, Q.; Wang, S.; Duan, L., and Jeng, D.-S., 2022. Experimental study on irregular wave (current)-induced pore-water pressures around a monopile. Journal of Coastal Research, 38(1), 114–132. Coconut Creek (Florida), ISSN 0749-0208.

In this study, a series of flume tests was systematically conducted to study the pore-water pressures around a monopile under wave and current loading, as well as the hydrodynamic response. Unlike in previous studies, the combined irregular wave and current action were studied, and a partially embedded monopile was considered. Moreover, the influence of wave spectra on the pore-water pressures was studied. The following results were obtained. (1) The irregular wave (current)-induced hydrodynamic response and seabed response around the monopile are stronger than those induced by the representative regular wave (current) loading. (2) A larger irregular wave energy can more often cause a larger pore-water pressure. The influence of irregular wave parameters on the pore-water pressures is mainly concentrated in the upper seabed, and the influence range is enhanced for the existence of current. (3) The current greatly influences the pore-water pressures in the upper and middle layers of the seabed; however, in the lower seabed below the monopile, it has a weaker but more complicated effect on the pore-water pressures. (4) Wave spectra have remarkable effects on the pore-water pressures, and the influence range deepens for the action of current on the wave field.

Williams, H.F.L. and Rains, B.J., 2022. Effect of barrier height on magnitude and character of Hurricane Harvey washover fans, Matagorda Peninsula, Texas, U.S.A. Journal of Coastal Research, 38(1), 133–139. Coconut Creek (Florida), ISSN 0749-0208.

This study uses topographic profiles, washover fan volumes, and shoreline retreat rates to explore relationships between barrier height, erosion, and storm washover sedimentation. Pre- and post-Hurricane Harvey topographic profiles were created along 15 transects using Bare Earth LIDAR (2016) and transit level surveys (2019). Washover fan thicknesses and areas were measured to estimate washover fan volumes. An inverse relationship was found between washover fan volume and pre- and poststorm barrier heights. One section of shoreline had a prestorm height of about 3 m, which almost completely blocked overwash, but may have contributed to a large increase in shoreline erosion. In contrast, a section of shoreline with a low prestorm barrier generated relatively large washover fans, but experienced lower shoreline retreat and was the only section to experience beach and dune recovery in the year after landfall. Shoreline retreat was further quantified between 2014 and 2018 using Google Earth imagery and LIDAR data from 2014, 2016, 2017, and 2018 to track migration of the shoreline. The entire shoreline in the study area is undergoing relatively rapid retreat, but the results suggest that Hurricane Harvey increased erosional retreat rates by up to 195%. The Colorado River Jetty borders the study area and may have acted as a barrier to wave erosion, contributing to enhanced marsh aggradation at marsh sites in close proximity to the jetty and promoting shoreline recovery in the poststorm period. The research results provide valuable information on the interaction of hurricane storm surge with natural and anthropogenic barriers, beach and dune erosion, and marsh aggradation along the coast of Texas.

Wang, Y.; Jiang, C.; Cheng, H.; Li, W., and Teng, L., 2022. Characteristics and driving mechanisms of mixing and stratification in the North Passage of the Changjiang estuary, China. Journal of Coastal Research, 38(1), 140–153. Coconut Creek (Florida), ISSN 0749-0208.

Based on the measured hydrological and sediment data of spring and neap tides in the dry and flood seasons of 2016 in the North Passage of the Changjiang Estuary, the gradient Richardson number, Simpson number, and potential energy anomalies were calculated to analyze the tidal cycle, spring-neap variation, and seasonal variation of mixing and stratification. Taking into account the vertical difference of horizontal density gradient, the contribution terms of time derivative of potential energy anomalies was derived, including depth-mean straining, advection, nonmean straining, and tidal stirring. The driving mechanisms of mixing and stratification was investigated by calculating and comparing these four contribution terms. The results show that the seasonal variation of freshwater discharge mainly affected the distance of saltwater intrusion, the saline wedge moved upstream in dry season, while the tidal dynamics had a significant impact on mixing and stratification. In the reaches with saline wedge tip migration, the water column was periodically stratified, and the process was dominated by advection term. In the main reaches of saltwater intrusion, during spring tide the water column was periodically stratified, which was stratified during flood tidal current; it was well mixed during ebb tidal current, and the stratification during flood tidal current was promoted by advection and depth-mean straining. The mixing during ebb tidal current was promoted by tidal stirring and advection; during neap tide, the water column was permanently stratified. The stratification was enhanced during flood tidal current and weakened during ebb tidal current, and the stratification was mainly maintained by depth-mean straining.

Elazzaoui, A.; Kalla, Y.; Lefrere, L.; Bouhaimi, A., and Moukrim, A., 2022. Using Mediterranean mussel bio-indicators to assess the initial health state of ecosystems receiving desalination plant effluents in Agadir Bay (Morocco). Journal of Coastal Research, 38(1), 154–167. Coconut Creek (Florida), ISSN 0749-0208.

Mussels are often used as a biological bio-indicator for the quality assessment of marine ecosystems. Adopting this approach, the present work aims to study the initial health status of two ecosystems in Agadir Bay, Morocco expected to receive seawater desalination plant effluents. This study was conducted between February 2015 and March 2017 in two stations, Tifnit-Douira and Cap Ghir. In addition to the gametic development, variations of sex ratio and gonadal index were also determined. The reproductive cycle of Mytilus galloprovincialis is spread throughout the year. Under natural conditions, three collective spawning periods were observed. The main one was during the spring and the two other periods were optional and were in winter and summer. Variations of seawater temperature can make some changes in mussel spawning, with one principal period lasting during spring and summer and the optional one during winter. In both studied stations, sexual rest was manifested by a small percentage of the population particularly during summer, and could not reach the whole population at the same time. This finding is consistent with the gonadal index that never reached the value of 1. A unique hermaphroditism case was revealed in Tifnit-Douira mussels, and it remained statistically insignificant. The sex ratio was perfectly balanced in both stations and was in favour of males. The gonad histology did not show any cellular abnormalities in the germinal tissue. These results are of great importance since they characterize the current state of the studied stations area before the installation of the desalination plant. This state must be maintained after installation in order to preserve the typical halieutic resources of these ecosystems. The present findings confirm the good environmental health status and the aquaculture potential of Agadir Bay, especially in the north ecosystems (Cap Ghir) due to upwelling-nutritional intake and optimum seawater temperature.

Makumbirofa, S.D. and Saayman, A., 2022. The influence of environmental value orientations on the overall scuba diving experience within a marine protected area. Journal of Coastal Research, 38(1), 168–181. Coconut Creek (Florida), ISSN 0749-0208.

This paper reports on the findings of a discrete choice experiment that aims to value the different attributes of the scuba diving experience in the Portofino Marine Protected Area (MPA), taking into account the various environmental value orientations of the divers. The attributes were divided into five different qualities—water visibility, diver crowding, species diversity, species number, and the willingness to pay—whereas the general awareness of consequences scale measured value orientations. Using a self-administered choice questionnaire, divers were asked to state their choice from different sets of attributes. A sample of 556 completed questionnaires were collected, with each respondent answering two random choice cards representing a choice between two different sets of attributes. A multinomial logit model was used to estimate scuba divers' willingness to pay for the various environmental attributes. The findings show that the most valued attribute for scuba divers in the Portofino MPA is underwater visibility followed by a less crowded dive site. The divers are predominantly egoistic in their value orientation, indicating that pro-environmental behaviour and intentions stem from self-interest. Regulations and education programmes that emphasise direct benefits to divers' diving experience would therefore encourage pro-environmental behaviour.

Zeng, C.-S.; Zhan, J.-M., and Hu, W.-Q., 2022. Numerical study on compound-slope seawalls with different types of protective facings. Journal of Coastal Research, 38(1), 182–195. Coconut Creek (Florida), ISSN 0749-0208.

The compound seawall is an important infrastructure to protect the coast effectively against tide and wave impacts. In this paper, a hybrid realizable k – ∊/laminar model and a volume of fluid interface capture method were used to study compound-slope seawalls with different types of protective facings. An analytical method was used to separate the incident wave and the reflected wave, and the numerical results for a compound-slope seawall with a hollow-block protective facing structure were verified by experimental results. The monitored wave surface, incident wave, and reflected wave data in the numerical simulation were compared with the experimental results, and the results show that the numerical model can simulate the interaction process of waves and compound-slope seawalls well. Furthermore, a series of numerical simulation studies on compound-slope seawalls under different protective facing structures with different wave heights, wave periods, water depths, and structure slopes was conducted. The results show that the hollow-block protective facings have a significant weakening effect on the reflected wave height, wave run-up, and wave force when the wave is moderate, which is important for the safety of seawall and onshore building structures.

Engin, S., 2022. The first commercially-scaled study on the influence of long dark and light photoperiod manipulation on the egg and larvae performance of rainbow trout (Onchorhynchus mykiss). Journal of Coastal Research, 38(1), 196–203. Coconut Creek (Florida), ISSN 0749-0208.

Spawning success, number of eyed-egg, and larval growth performance of rainbow trout are largely affected by a variety of biotic and abiotic factors. The photoperiod is important in initiating or suppressing breeding timing and gonadal maturation that varies by species. The aims of this study were to investigate the effect of two different commercial photoperiod manipulations on the growth of total eyed eggs, egg diameter, and larvae under specific fish farm conditions. The control group (outdoor broodstock ponds and natural sunlight) fish were fed using a commercial broodstock feeding protocol in September and transferred to the hatchery in February for spawning. The female and male broodstocks were exposed to direct photoperiod (Experimental Group 1: M1), and for the adapted photoperiod (transition from light to dark periodically, Experimental Group 2: M2) they were exposed to 18 hours of light and 6 hours of darkness between January and April. The M1 group were exposed to a direct application of 18 hours of dark and 6 hours of light, and a transition from light to dark for 18 hours and from dark to light for 6 hours was applied to M1 that was completed over 48 days with a daily decrease of 17 minutes. The results of the trials showed that larval growth was higher in the groups treated with long light and long dark, 18 hours light/6 hours dark and 18 hours dark/6 hours light compared to the control group, and statistically significant difference between larval survival rate and daily weight gain was observed between all three groups (p < 0.05). As a result, at the end of the photoperiod, applications and larvae breeding performed for one year under commercial operating conditions were compared, and larvae with higher survival and growth rates were obtained with long light and long dark application.

Sun, P.; Zhou, J.; Liu, Y., and Wang, Y., 2022. Lattice Boltzmann method for simulations of nozzle flows in coastal environments. Journal of Coastal Research, 38(1), 204–217. Coconut Creek (Florida), ISSN 0749-0208.

A better understanding of flow in pipes is considered to be critical for marine equipment because it helps to improve pipe performance related to vibration and structure problems. In this study, flow simulations were conducted using a large–eddy-simulation lattice Boltzmann method (LES-LBM) in a nozzle under various Reynolds numbers (Re) and the effect of the three-dimensional cubic lattice models D3Q15, D3Q19, and D3Q27 was examined. The results show that when Re < 200 (i.e. the asymmetry of the results calculated using lattice models D3Q15 and D3Q19 is below 5%) or when the lattice model D3Q27 is adopted, computational results can satisfy the requirement of rotational invariance. When 250 < Re < 300 or the flow suddenly traverses an abrupt expansion, the isotropy of lattice models D3Q15 and D3Q19 experience “collapse”. Defective planes cannot be used to completely solve complex flows and accurately transfer flow information. The resultant problems in the computational results include preference in the circumferential distribution of axial velocity and contraction effects of the phase portrait of axial and radial velocities. More complex flows (e.g., for situations with large Re or fluid traversing abrupt expansion) universally cause more significant lattice model effects, where nonlinear flow phenomena become dominant. Therefore, it is necessary to ensure that solutions in the entire computational domain are independent of lattice orientation during flow simulation using LBM. Overall, the results in this paper have important potential applications in predicting flow characteristics for pipe flows in marine structures such as marine risers in coastal environments and zones farther out to sea.

Gou, L.; Yang, S., and Ren, L., 2022. Coupling analysis of the quality and quantity of marine economic growth from the perspective of high-quality development. Journal of Coastal Research, 38(1), 218–228. Coconut Creek (Florida), ISSN 0749-0208.

The transformation of a marine economy to one based on quality and efficiency is imperative for building maritime power and enabling high-quality marine development. High-quality development can be achieved by developing the marine economy in terms of both quantity and quality. Understanding the coupling between quality and quantity is, therefore, instrumental to governments' decision-making processes, particularly when trying to improve quality and ensure efficiency. This paper presents a case study of China's Shandong Province. After an in-depth discussion on the definition of quality in terms of marine economic growth, a system of indicators was constructed (based on five dimensions) to evaluate the quality of marine economic growth. Following this, a set pair analysis was used to measure the quality. Finally, coupling and coordination models and kernel density estimation were employed to identify patterns in the dynamic coupling between quality and quantity. The results showed that from 2006 to 2016, the quality of marine economic growth in Shandong Province generally followed an upward trend. Furthermore, the growth in quantity was increasingly driven by the trends in quality. However, with a decreasing coupling degree and coupling and coordination degrees between quantity and quality, there is still considerable room to improve coordination.

Duan, P.; Cao, Y.; Wang, Y., and Yin, P., 2022. Bibliometric analysis of coastal and marine tourism research from 1990 to 2020. Journal of Coastal Research, 38(1), 229–240. Coconut Creek (Florida), ISSN 0749-0208.

Coastal and marine tourism (CMT) has become a growing and important subsector of the tourism industry in recent years. To identify the state of and trends in the field, a bibliometric analysis of CMT was conducted to evaluate global productivity over the past 31 years (1990–2020). All relevant publications in the analysis were extracted from the Web of Science Core Collection database. As a result, the review found that the identified 6190 documents showed an upward trend during this time period. The most productive and influential countries, institutions, and authors were also identified in this analysis, and the distribution of subject categories and journals was analyzed. VOSviewer was used to analyze the coauthorships among countries, institutions, and authors. Based on an analysis of the high-frequency keyword co-occurrence network, four major CMT research topics were identified: (1) the sustainable development of CMT, (2) the impact of CMT on destinations, (3) CMT management and conservation, and (4) the impact of climate change on CMT. This analysis can help reveal and determine the research focus and trends in the CMT field.

Dong, W.; Yang, Q.; Huang, X.; Chen, Y., and Sun, S., 2022. Development of underwater wireless sensor networks (UWSNs): Using MAC protocol with concurrent transmission based on slotted FAMA. Journal of Coastal Research, 38(1), 241–248. Coconut Creek (Florida), ISSN 0749-0208.

With the continuous development of ocean research in recent years, as an extension of terrestrial wireless sensor networks, underwater wireless sensor networks play an increasingly important role in ocean and coastal research. The handshaking efficiency in the traditional slotted floor acquisition multiple access (FAMA) is low. After a successful handshake, only one node is allowed to send data. Moreover, there are unnecessary back-off problems; thus, the channel utilization is low. Aiming at improving the shortcomings of the traditional slotted FAMA, this paper proposes a Medium Access Control protocol with concurrent transmission based on slotted FAMA (SFAMA-CT). The sending node uses the long propagation delay of the network to maintain a sending matrix according to the position information of the nodes in the propagation range. The value of each element of the sending matrix is determined by whether two nodes can simultaneously send data without collision. Then, the sending node determines whether it can choose to send in the DATA phase according to the number of received X Clear-To-Send (XCTS) packets (where “X” indicates a CTS packet intended for another node) and element information of the sending matrix. The proposed protocol has higher handshake efficiency and improves the concurrent transmission of the network compared to that of other protocols. The simulation results show that, compared to slotted FAMA and SFAMA-data train (DT), the throughput of SFAMA-CT is increased by approximately 115% and 20%, respectively. SFAMA-CT also has good performance in the end-to-end delay.