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Zhang, Y.; Yan, S.; Wang, W., and Wang, M., 2021. Habitat use by fish across tidal cycles in a tropical estuarine mangrove ecosystem (Dongzhaigang Bay, Hainan, China). Journal of Coastal Research, 37(1), 156–167. Coconut Creek (Florida), ISSN 0749-0208. Mangroves wetlands are recognized as nursery areas for large numbers of marine organisms. Yet, many properties of this nursery function remain poorly understood. In this study, the seasonal use of a tropical mangrove bay by fish assemblages over tidal cycles was investigated in 2009. Fish were sampled using centipede nets from three sites (located in the mouth, middle, and top of the bay) at Dongzhaigang Bay, Hainan, China. At each site, three replicates were sampled from each of the three different habitat types (i.e. vegetated area, creek, and mudflat). A generalized linear mixture model was used to explore the spatial and temporal variations in fish assemblages. The results showed that fish species richness, abundance, and biomass per sampling unit were significantly lower in the vegetated areas and mudflats than in the creeks. In the vegetated areas, fish species richness, abundance, and biomass per sampling day were significantly higher during spring tides than during neap tides. However, a similar pattern was not found both along the creeks and on the mudflats. In addition, tidal height showed a positive effect on biomass per sampling unit, especially in the vegetated areas; meanwhile, effects on species richness and abundance were not significant. The results indicate that larger tidal amplitude could support more fish (both richness and abundance) in the vegetated areas, which might occur because larger tidal amplitude provides fish with access to more habitats. These results provide basic knowledge related to mangrove management at an important fish nursery ground. [ABSTRACT FROM AUTHOR]

Cialone, M.A. and Slusarczyk, G., 2020. Impact of inlet closures on surge response in New Jersey back bays. Journal of Coastal Research, 36(6), 1111–1120. Coconut Creek (Florida), ISSN 0749-0208. The in-depth study presented in this paper includes numerical modeling and analysis of the effects of storm surge barriers (inlet closures) on water levels in the back bays of New Jersey during storm events. Eleven inlet closures were each numerically "closed" singularly and in combination with other inlet closures. Storm surge simulations were run with all 11 inlets "open" as a base condition and for each of the inlet singular closure and combination closure conditions. In this paper, four combinations of inlet barrier positions were selected to demonstrate the ability of surge barriers to potentially prevent surge propagation into the back bays of New Jersey, including: (1) the base condition (all inlets open); (2) closing one of the larger entrances, Barnegat Inlet; (3) all inlets closed except for a small inlet (Corson Inlet) and an extremely wide inlet entrance (Little Egg/Brigantine Inlet); and (4) all inlets closed. A comparison of maximum surge envelopes and water-level time series from simulations of 10 synthetic tropical storms with the inlets in these four configurations was made. Three of the largest bay systems, Barnegat Bay, Manahawkin Bay, and Little Egg Harbor, are the main focus of this paper. As expected, the greatest reduction in water level in the bays occurs when all inlets are closed with surge barriers. The average reduction in water level for the three bays mentioned above with all inlets closed is 0.70 m, with a maximum average reduction in Little Egg Harbor of 0.73 m. Simulations with only Barnegat Inlet closed show the greatest reduction in water level in the northern portion of Barnegat Bay, whereas surge can still propagate into the southern portion of the bay through Little Egg/Brigantine Inlet. However, storms with strong N-to-S wind can inhibit flow entering from the open inlet at Little Egg/Brigantine and therefore show the greatest reduction in maximum water level in the southern portion of Barnegat Bay for these conditions. With some inlets open and some closed, strong alongshore winds can also cause surge to become trapped behind adjacent inlet closures. This demonstrates the importance of considering multiple means of flow propagation into an embayment as well as the timing of implementing surge barriers to optimize surge protection. [ABSTRACT FROM AUTHOR]

McDonald, K.L., 2020. Differences in the morphology of restored and invaded foredunes on the North Spit of Humboldt Bay, California, U.S.A. Journal of Coastal Research, 36(5), 973–980. Coconut Creek (Florida), ISSN 0749-0208. Invasive plants have altered wide-ranging coastal dune vegetation communities worldwide, and the effects of nonnative vegetation and invasive plant management on dune geomorphology are of interest to many coastal land managers, researchers, and coastal communities. This study compared the slopes, elevations, and profiles of invaded and restored foredunes on the North Spit of Humboldt Bay, California, using data from a high-resolution 2010 digital elevation model. Restoration of foredunes by removing invasive European beachgrass (Ammophila arenaria [L.] Link) took place over the last three decades in approximately half of the study area, and the restored areas now primarily support American dunegrass (Elymus mollis Trin.) and other native dune species. Despite recently voiced public concerns that restoration might be permanently lowering the foredune, restored and invaded areas showed no significant difference in height. However, invaded foredunes were significantly steeper with a flatter, plateau-like top, while restored areas were more gently sloping with rounded peaks. Foredune heights increased from the southern end of the study area to the north, regardless of restoration status, suggesting that other factors control foredune height. [ABSTRACT FROM AUTHOR]

Al-Aesawi, Q.; Al-Nasrawi, A.K.M., and Jones, B.G., 2020. Short-term geoinformatics evaluation in the Shatt Al-Arab delta (northwestern Arabian/Persian Gulf). Journal of Coastal Research, 36(3), 498–505. Coconut Creek (Florida), ISSN 0749-0208. Riverine deltas are records of past hydrosedimentary conditions, in conjunction with nearshore tidal and wave dynamics. Within recent human developments, these variables have been affected by increased global warming as well as anthropogenic modifications on the feeder catchment, the delta itself, and the active/discharge channel. This paper investigates the recent (1971–2016) changes at the mouth of the Shatt Al-Arab delta, which includes migration of the navigation channel to inside the Iraqi border. Farther upstream, the channel is migrating toward the Iranian side. A mapping study was conducted with new data obtained from bathymetric surveys as used in the digital shoreline analysis system in GIS applications. The results highlight significant changes regarding the shoreline positions and rates of erosion and sediment accumulation. Additionally, mapping the coastal dynamics has revealed significant shoreline migration with differences between the left and right sides of the river mouth and an increased salinity intrusion up the channel. The effect of these findings could potentially affect the classification of the river mouth, changing it from delta to estuary and affect the international demarcation border. [ABSTRACT FROM AUTHOR]

Yoon, H.H.; Chun, S.S., and Hong, S.H., 2020. Rapid change in sedimentary facies from wave- to tide-dominated macrotidal flat in the Sinduri Bay, west coast of Korea. In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 728-732. Coconut Creek (Florida), ISSN 0749-0208. Macrotidal wave-dominated coastal environments are widely distributed on the western open coasts of Korea, although various muddy intertidal flats occur also in the inner part of embayed areas influenced strongly by geomorphological factor. The surface sediment of wave-dominated sandflat and tidal beach, which are developed on the northern Sinduri Bay coast, consists mostly of very well sorted medium to fine sand. Swash bars, which are parallel to the coastline and continuously migrating landward, play the important role in the formation of this macrotidal sandflat. The surface sedimentary facies in this southern embayed area consists mostly of mud. The mud flat is very gentle in slope with slight concave-up profile, and dominantly shows a highly bioturbated mud facies. The distribution of surface sedimentary facies, slope profile, hydrodynamic analysis and the transport pattern of coarse-grained sediment show a rapid change in sedimentary facies with very narrow transition zone from wave-dominated sandflat facies to tide-dominated mudflat facies. Both wave- and tide-dominated coasts have been formed together within a small single geomorphological unit. The co-occurrence of different types of coasts and the rapid shift of sedimentary facies can be indicative of one of characteristics in the macrotidal open-coast depositional environment in which geomorphology, sediment supply and hydrodynamic factors have been closely associated within a relatively small bay area. Sedimentary processes in the two coastal sytems are separated and independent each other. The development of separated depositional systems are also evident even in cored sediments, indicating that the recent depositional setting has been continued much longer time. [ABSTRACT FROM AUTHOR]

Woo, H.J.; Lee, J,-H.; Choi, J.U., and Kang, J., 2020. Changes in sedimentary processes in macrotidal flats in Garolim Bay, West Coast of Korea. In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 722-726. Coconut Creek (Florida), ISSN 0749-0208. Garolim Bay, on the central western coast of Korea, is a semi-enclosed macro-tidal bay with extensive tidal flats that occupy approximately 77% of the bay surface area. The study investigated the sediment characteristics and sedimentation rates to elucidate the spatial and temporal variations in the sedimentary processes in the bay. Surface sediments were sampled to grain-size distributions at 158 stations in July 2002 and July 2014 in the spring tidal cycle. Grain-size distributions were analyzed using standard sieving for the sand fraction and a particle size analyzer for the mud fraction. The geomorphic changes associated with sediment deposition or erosion were investigated along six transect lines on the tidal flats from February 2014 to February 2015 in the ebb tide. The area of sand and muddy sand sediments had extended from the outer to the middle bay in summer 2014, and the percentages of mud were higher in the inner bay compared to the surface sediment distributions in summer 2002. The short-term sedimentation rates from February 2014 to February 2015 showed that erosion was dominant on the tidal flats in the inner bay during spring and on those in the outer bay during winter, with net erosion rates of –1.55 and –55.23 mm/year, respectively. In the middle bay, deposition dominated on the tidal flats, with net deposition rates from 4.85 to 18.94 mm/year. The sediment transport vectors calculated using grain-size parameters for 2002 and 2014 showed that in 2002, sandy sediments were predominantly transported along tidal channels at the bay entrance. However, in winter, sediments from the tidal flats in the outer and middle bay areas are transported to the inner bay by wind-driven waves and tidal currents, resulting in the deposition of sediment on the tidal flats in the inner bay. In summary, the results show that the sediment transport patterns in Garolim Bay changed between 2002 and 2015 due to increased suspended sediment supply and erosion of the tidal flats in the outer bay. Based on these knowledge of sedimentary processes, the major control factors for seasonal variations in sedimentation on the tidal flats in Garolim Bay are tidal currents, wind-driven waves, and sediment inputs. [ABSTRACT FROM AUTHOR]

Solana, G.; Grifoll, M., and Espino, M, 2020. Hydrographic variability and estuarine classification of Inhambane Bay (Mozambique). In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 649–653. Coconut Creek (Florida), ISSN 0749-0208. This study investigates the hydrographic variability and the estuarine classification obtained from a set of field campaign data in Inhambane Bay (Mozambique). In situ measured salinity, temperature and sea-level data, together with Sea Surface Temperature (SST) obtained from GHRSST project, enabled to investigate the seasonal and inter-annual variability of the hydrography of the bay. Inhambane Bay is a bifurcated two-channel bar-built estuary with an along-coast channel of 30.5 km and a secondary channel of 12.5 km. In terms of tidal classification, Inhambane Bay is classified into the meso-tidal category forced by semi-diurnal tides with a Form Number equal to 0.04. The maximum observed tidal range is ∼3.41 m, with mean spring and neap tidal ranges of ∼2.61 m and ∼1.34 m, respectively. Also, the mean salinity profiles are practically uniform (well-mixed estuary) due to the strong tidal forcing being the Richardson Estuarine number below 0.08. The flushing time is estimated between 1 and 3 days. The characterization presented in this research is novel in the region and involves for the first time systematic in situ observations. The conclusions may be useful for similar unexplored areas along the Mozambican coast. [ABSTRACT FROM AUTHOR]

Lu, Z.; Zhan, X.; Guo, Y., and Ma, L., 2020. Small-scale effects of offshore wind-turbine foundations on macrobenthic assemblages in Pinghai Bay, China. Journal of Coastal Research, 36(1), 139–147. Coconut Creek (Florida), ISSN 0749-0208. In recent years, offshore wind farms in China have developed rapidly, especially in SE coastal regions. The construction of wind-turbine foundations (WTFs) introduces new artificial structures into coastal ecosystems, influencing the surrounding macrobenthos. Small-scale effects on macrobenthic assemblages around a high-rise cap pile WTF in Pinghai Bay, China, were investigated in November 2017 and May 2018, along SW and SE gradients. The macrobenthic abundance increased from 220 ± 92 individuals (ind) m–2 at 200 m to 547 ± 103 ind m–2 at 25 m from the foundation, and the species number increased from 8 ± 3 at 200 m to 16 ± 6 per sample at 25 m from the foundation, whereas the biomass decreased from 17.2 ± 2 g m–2 at 200 m to 3.1 ± 1.4 g m–2 at 25 m from the foundation. The macrobenthic abundance increased by 94.75% compared with that before the WTF construction. Abundance significantly increased from 179 ± 115 to 463 ± 255 ind m–2 for Annelida, from 62 ± 56 to 99 ± 77 ind m–2 for Arthropoda, and from 4 ± 3 to 22 ± 25 ind m–2 for Echinodermata. However, the abundance of Mollusca decreased from 65 ± 100 to 14 ± 22 ind m–2. Thus, it is likely that most macrobenthos were able to recover quickly after the deployment of WTF, whereas more time might be needed for Mollusca to recover. There was also an obvious shift in species dominance, with Annelida becoming the dominant group (73.28–77.78%) in the macrobenthic community. [ABSTRACT FROM AUTHOR]

Millán-Aguilar, O.; Nettel-Hernanz, A.; Hurtado-Oliva, M.Á.; Dodd, R.S.; Flores-Cárdenas, F., and Manzano-Sarabia, M., 2020. Landscape metrics and conservation status of five mangrove wetlands in the eastern Gulf of California margin. Journal of Coastal Research, 36(1), 94–102. Coconut Creek (Florida), ISSN 0749-0208. Ecological significance and relevance of mangrove wetlands has been widely highlighted worldwide. Nevertheless, human-derived impacts and climate variability are increasing threats to these ecosystems in the last decades. Mangroves from Sinaloa (Mexico) integrate a large wetland corridor and provide several ecosystem services; however, diverse stressors could be increasing their vulnerability and associated biodiversity. The conservation status of five mangrove wetlands in this region was assessed through remote sensing techniques, landscape metrics, official databases and in situ records. In general, a decrease on mangrove cover was observed, excepting Estero de Urías and Ceuta, while aquaculture increased in all sites, with a greatest coverage in Santa María-La Reforma (increased 2057 ha in 18 years). The largest annual rate of change was observed in Huizache-Caimanero (–0.99%). Although conservation programs exist, there are signs of deterioration of mangrove wetlands according to this study. [ABSTRACT FROM AUTHOR]

Wu, B.; Jin, H.; Gao, S.; Xu, J., and Chen, J., 2020. Nutrient budgets and recent decadal variations in a highly eutrophic estuary: Hangzhou Bay, China. Journal of Coastal Research, 36(1), 63–71. Coconut Creek (Florida), ISSN 0749-0208. Hangzhou Bay is one of China's most eutrophic waterbodies, yet water quality observations within the bay are few, and the estuary's nutrient dynamics are poorly understood. Five cruises (summer, autumn, winter, spring) were conducted in Hangzhou Bay and adjacent waters between July 2006 and November 2007 and in August 2018. A steady-state box model was also constructed to estimate summer and winter nutrient fluxes. The results show that the spatial distributions and temporal variations of nutrients within the bay are significantly influenced by not only direct inputs from rivers around the bay but also the Changjiang River plume to the north. Bay concentrations of nitrate (), dissolved inorganic phosphorus (DIP), and dissolved silicate (DSi) were quite high throughout the year, especially in the head of the bay. Relative to concentrations measured in 1981–1982, estuarine concentrations of and DIP had increased, whereas DSi had been stable. The model results indicate that riverine discharge is the major source of nutrients to Hangzhou Bay. In both summer and winter, nutrients were exported from the bay to the East China Sea. The fluxes of , dissolved inorganic nitrogen (DIN), DIP, and DSi were higher in summer than winter, but the flux of ammonium was higher in winter. Nutrient fluxes to Hangzhou Bay observed here during 2006–2007 are much higher than those observed in the 1980s. Additionally, nutrient abundances in Hangzhou Bay are significantly higher than those reported for other coastal embayments in China. The difference in algal blooms inside and outside the bay is possibly due to the difference in turbidity or the hydrological conditions. [ABSTRACT FROM AUTHOR]

Ye, Y.; Chen, K., and Huo, Y., 2019. Long-term change of environment and it's influence on phytoplankton community structure in Daya Bay. In: Hoang, A.T. and Aqeel Ashraf, M. (eds.), Research, Monitoring, and Engineering of Coastal, Port, and Marine Systems. Journal of Coastal Research, Special Issue No. 97, pp. 191–197. Based on the phytoplankton samples in Daya Bay from 2004 to 2016, the data of environmental factors were collected simultaneously to analyze the long-term changes of environmental factors and their effects on phytoplankton community structure. Our results showed that nutrient concentration in Daya Bay increases year by year, which was caused by the rapid economic development around Daya Bay and a large amount of industrial and agricultural wastewater and domestic sewage discharged into the water. As a result, the concentrations of nitrogen and phosphorus in Daya Bay were much higher than the growth threshold of phytoplankton. Therefore, the change of environmental factor has an important impact on the community structure of phytoplankton in Daya Bay. The dominant species had obvious succession in Daya Bay, and the species that preferred fertilizer increased significantly and became the dominant species. [ABSTRACT FROM AUTHOR]

This study presents the results of LiDAR surveys, spanning 15 years (2002-2017), of the shallow inner sector of Mont-Saint-Michel Bay, a megatidal embayment in Normandy, France, and a UNESCO World Heritage site famous for its monastery. The objective of these surveys was to obtain a better understanding of the morphodynamic processes in this megatidal environment. The campaign has highlighted the circumstances and very short timescales at which changes occur in the channel configuration of the inner bay. It has also been demonstrated the high variability of sediment import and export, which involves not only the tide, but also wind speed and direction. Part of the variability is also related to fluctuations in river discharges into the bay. Since 2009, engineering works have been carried out in the bay. These are aimed at re-establishing the maritime character of the bay around the granite outcrop (Mont-Saint-Michel) on which was built the monastery, and which was increasingly subject to accretion. The main channel of the inner bay shifted recently to a more southward position than observed during the past decades. Yet, from the topographic LiDAR data up to May 2017, it is presently not possible to identify the influence of the engineering works on sedimentation processes beyond a limited zone around the Mont. However, the pursuit of LiDAR surveys is necessary in order to determine whether, in the course of the next decade, the North-South migrations of the Sée-Sélune channel induced by the 18.6 y nodal cycle are affected or not by these works. [ABSTRACT FROM AUTHOR]

The article focuses on surfing resource, Manu Bay located in New Zealand and outlines its wave quality, consistency and uniqueness.

The article offers information on Waikeri at Manu Bay in Waikato, New Zealand.

Based on outcrops, rock cores, seismic, well logging, and other data, the study traces the evolutions of sequence stratigraphy, the types of sedimentary facies and sequence development control factors of Es3 in the Kenxi slope zone of Bohai Bay basin. The findings show that the stratum in this area can be divided into three third-order sequences, eleven fourth-order sequences and seven system tracts; the types of sedimentary facies include fan delta, sublacustrine fan, semi-deep lake, and deep lakes, etc.; sedimentary facies belt, lithologic trap patterns, hydrocarbon migration and preservation conditions are the core factors controlling lithologic reservoirs in this area. The exploration prospect in this area have been predicted. It is believed that there is a large exploration potential in the upper Es3 sub-member, the south of well K25-1 of the west Kenxi prominence. [ABSTRACT FROM AUTHOR]

With the development of marine resources and human activities along the coast, seawater pollution has become a crucial topic. Monitoring and evaluation of seawater quality is an important reference for human to understand the marine ecological environment. This paper uses the T-S fuzzy neural network to evaluate the quality of seawater in Hangzhou Bay. The result shows that the water quality in Hangzhou Bay is at a poor level. This conclusion is consistent with the result of the Official Report of China Offshore Quality. [ABSTRACT FROM AUTHOR]

Chen, B.; Dong, D.; Qin, X.; Xu, M.; Chen, X., and Shi, M., 2019. Relationship between the occurrence of red tides and the dynamic response mechanisms in the northern Beibu Gulf. In: Guido-Aldana, P.A. and Mulahasan, S. (eds.), Advances in Water Resources and Exploration. Journal of Coastal Research, Special Issue No. 93, pp. 185–193. Coconut Creek (Florida), ISSN 0749-0208. Unlike the common outbreak mechanism of red tides, the northern Beibu Gulf in the Guangxi Zhuang Autonomous Region of China experiences frequent red tides with distinct characteristics, such as large distances from the mainland and the presence of industrial pollution. By tracing the sources and transport of the high concentrations of nitrogen and phosphorus, the relationship between pollutant transport and the dynamic response mechanisms was explored. The results showed that the concentrations of nitrogen and phosphorus nutrients in the areas of red tide outbreaks near Weizhou Island and in the Qinzhou Gulf in the northern Beibu Gulf were higher than those in the surrounding areas. However, the high concentrations of nitrogen and phosphorus nutrients in the northern Beibu Gulf did not originate from terrestrial pollution from Guangxi Province; rather, these pollutants originated on the east coast of China and were transported through the Qiongzhou Strait. The primary sources were the Pearl River Estuary and the coastal waters of eastern Guangdong. In addition, the differences in the concentration distributions of nitrogen and phosphorus nutrients between the east and west coasts of the Qinzhou Gulf in the northern Beibu Gulf were clearly related to dynamic response mechanisms. [ABSTRACT FROM AUTHOR]

Unlike the common outbreak mechanism of red tides, the northern Beibu Gulf in the Guangxi Zhuang Autonomous Region of China experiences frequent red tides with distinct characteristics, such as large distances from the mainland and the presence of industrial pollution. By tracing the sources and transport of the high concentrations of nitrogen and phosphorus, the relationship between pollutant transport and the dynamic response mechanisms was explored. The results showed that the concentrations of nitrogen and phosphorus nutrients in the areas of red tide outbreaks near Weizhou Island and in the Qinzhou Gulf in the northern Beibu Gulf were higher than those in the surrounding areas. However, the high concentrations of nitrogen and phosphorus nutrients in the northern Beibu Gulf did not originate from terrestrial pollution from Guangxi Province; rather, these pollutants originated on the east coast of China and were transported through the Qiongzhou Strait. The primary sources were the Pearl River Estuary and the coastal waters of eastern Guangdong. In addition, the differences in the concentration distributions of nitrogen and phosphorus nutrients between the east and west coasts of the Qinzhou Gulf in the northern Beibu Gulf were clearly related to dynamic response mechanisms. [ABSTRACT FROM AUTHOR]

Huang, H.; Cai, L.; Luo, Y.; Wang, J.; Liu, Y.; Sun, X.; Lin, H., and Wang, W., 2018. Distribution and potential ecological risk assessment of heavy metals in surface sediments of Xiamen Bay. In: Wang, D. and Guido-Aldana, P.A. (eds.), Select Proceedings from the 3rd International Conference on Water Resource and Environment (WRE2017). Journal of Coastal Research, Special Issue No. 84, pp. 125–133. Coconut Creek (Florida), ISSN 0749-0208. The present work envisages the potential ecological risk assessment of heavy metals in surface sediments of Xiamen Bay. Based on the survey of the surface sediments in May 2012, the concentrations of heavy metals Cu, Pb, Zn, Cd, Cr, Hg and As in sediments were 1.2~57.2, 6.7~76.6, 13.3~150.0, 0.035~0.531, 1.48~92.7, 0.018~0.164, 1.9~10.9 mg.kg−1, respectively. Significant positive correlations were observed amongst the concentrations of Cu, Zn, Hg and As and Total Organic Carbon (TOC). PCA analysis data showed the first three main factors shared 72.70% of the total variance. All stations in the studied area recorded Eir < 40 for Cu, Pb, Zn, Cr and As, which were low risk, while Cd reported the highest ecological risk. The results of refractive index (RI) showed that 40.9% of stations in the Xiamen Bay were at a low risk, 45.5% of them were at a moderate risk, while 13.6% were at high ecological risk. [ABSTRACT FROM AUTHOR]

Feng, J.-B.; Ren, C.-H.; Luo, P.; Yan, Y.; Jiang, X., and Hu, C.-Q., 2018. The response of bacterial community structure to ecological environment changes in Daya Bay between winter and spring. In: Wang, D. and Guido-Aldana, P.A. (eds.), Select Proceedings from the 3rd International Conference on Water Resource and Environment (WRE2017). Journal of Coastal Research, Special Issue No. 84, pp. 19–29. Coconut Creek (Florida), ISSN 0749-0208. The distribution patterns of the bacterial biomass and its diversity were investigated in Daya Bay in winter and spring 2008. Based on the acridine orange direct count, the mean bacterial biomass (0.31±0.20 μg L−1) in spring was 1.5 times more than that (0.21±0.07 μg L−1) in winter. Spatially it showed the trend that the mean bacterial biomass at station surface and bottom layers in the south of the bay was higher than in the north of the bay. The results based on PCR-DGGE and DNA sequence analysis showed that the Proteobacteria group dominated in bacterial communities of Daya Bay and other groups included the Cyanobacteria , Actinobacteria and Verrucomicrobia. The mean bacterial apparent species richness (No. of DGGE bands) was distinctly higher in winter (18) than in spring (12). It was concluded that phytoplankton controlled bacterioplankton biomass by utilizing dissolved inorganic nitrogen (DIN) in winter and spring. The observed seasonal variations of bacterioplankton community composition in Daya Bay was mainly associated with the high-in-winter-and-low-in-spring availability of nutrients like DIN and SiO32−-Si. [ABSTRACT FROM AUTHOR]

ABSTRACT Ying, C.; Li, R.; Li, X., and Liu, Y., 2018. Anthropogenic Influences on the Tidal Prism and Water Exchange in Yueqing Bay, Zhejiang, China. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 961–965. Coconut Creek (Florida), ISSN 0749-0208. Yueqing Bay (YQB) is a semi-enclosed, calabash-shaped bay with shallow water depths and a large tidal range in the East China Sea that is relatively narrow in the middle and wide at its top and mouth. YQB has been subjected to considerable human activity, including reclamation and dam construction projects, over the past 50 years. To understand the changes in the hydrodynamics and water exchange abilities in YQB with respect to these anthropogenic influences, the tidal prism (TP) and water residence time (WRT) of YQB during the years 1964, 1984, 2002, and 2012 were investigated using a calibrated, two-dimensional hydrodynamic model based on the finite volume method. The simulation results show that the TP of YQB decreased by 21.3% and that the WRT increased by over 80%. The water exchange ability of YQB decreased continuously, especially during 1964–1984. The TP and WRT both show nonsynchronous historical changes with anthropogenic influences due to engineering intervention methods. The inner and outer parts of YQB exhibited considerably different sensitivities to anthropogenic influences due to the calabash shape of the bay. Large-scale engineering construction projects in coastal zones imposed significant impacts on the hydrodynamic characteristics in YQB that may have led to potential environmental and ecological issues. [ABSTRACT FROM AUTHOR]

ABSTRACT Abadie, S.; Beauvivre, M.; Egurrola, E.; Bouisset, C.; Degremont, I., and Arnoux, F., 2018. A database of recent historical storm impact on the French Basque coast. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 721–725. Coconut Creek (Florida), ISSN 0749-0208. A coastal storm damage database covering 64 years was built based on press and archives investgations. Flooding of Biarritz La Grande Plage sea front and related damages were characterized with a three level index along with binary reliability indicator. Damages to breakwaters protecting Saint Jean de Luz bay were also documented. Building such a database appeared to be extremely time consuming and also implies some limitations mainly due to the heterogeneity and incompleteness of the data sources. 30 flooding events were reported for Biarritz among which the five most destructive ones were December 28–29, 1951, November 9–10, 2010 and January 4–7, February 1–2, March 3–5, 2014. This clearly shows the extreme character of winter 2014. [ABSTRACT FROM AUTHOR]

ABSTRACT Ab Razak, M.S.; Suryadi, F.X.; Jamaluddin, N., and Mohd Noor, N.A.Z., 2018. Shoreline Planform Stability of Embayed Beaches Along the Malaysian Peninsular Coast. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 631–635. Coconut Creek (Florida), ISSN 0749-0208. The existence of embayed beaches is pronounced along the coast of Peninsular Malaysia. The stability of such beaches is yet to be confirmed. The present study aims at investigating the shoreline planform stability on the east and west coasts of Peninsular Malaysia. 190 embayed beaches were found along the Malaysian Peninsular coast, including natural beaches and man-made beaches. Of these, 139 beaches were on the west coast while 51 beaches were on the east coast. Results of the MEPBAY model show along the east coast, 45%, 51% and 4% were classified as the static, dynamic, and natural beach reshaping, respectively. Beaches on the west Peninsular coast that is mainly characterised by the muddy coast were more pronounced to be in the static state which comprised of 85% compared to the beaches on the east coast, that are mostly sandy. While, another 15 % were fall under dynamic equilibrium state. Sediment supply from the river, improper placement of coastal structures, sediment bypassing at headland are some possible factors that may cause the dynamic and instability of the embayed beaches studied. [ABSTRACT FROM AUTHOR]

ABSTRACT Bitoun, R.E.; Collin, A.; James, D., and Pioch, S., 2018. Modelling Saltmarsh Spatial Evolution at High Resolution from 1948 to 2100. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 676–680. Coconut Creek (Florida), ISSN 0749-0208. Saltmarshes are boundary sea-land-air ecosystems which are globally threatened despite the plethora of ecosystem services they provide. Their evolution is spatially complex and multifactorial, influenced mostly by ecological and physical drivers such as tidal range, wave energy, hydrologic components and climatic conditions. Saltmarshes can respond positively to climate change due to their adaptiveness especially in areas provided with high tidal energy. While the conditions and determinants of marsh evolution are known locally, the spatial mapping of such processes across time is strongly expected. It is hereby proposed to study the interactions of the spatial evolution of Beaussais' Bay saltmarsh (France) from 1948 to 2013 by means of ocean-climate data. Time series of the saltmarsh spatial response, based on five high resolution aerial photographs, were explained by a multiple linear regression on continuous temperature, precipitation and mean sea level data. The model significantly explained the average horizontal accretion of the marsh platform by local warming and rising sea-level (Pearson's correlation coefficient r=0.63, RMSE=5.22). The increase in temperature explains best the model (R2=0.88), while sea-level and precipitation are secondary predictors (R2=0.16 and R2=0.11, respectively). The model enabled fine-resolution mapping to be predicted based on both IPCC ocean-climate scenarios and historical trends of the marsh surface up to 2100. The findings confirm the trends observed so far, enhancing the importance of saltmarsh conservation as a coastal protection. Spatial modelling of the marsh platform evolution constitutes therefore an intuitive framework and accessible communication tool for coastal planners. [ABSTRACT FROM AUTHOR]

ABSTRACT Gómez, M.; Villagrán, M.; Martínez, C., and Belmonte, A., 2018. Characterizing the Longshore Sediment Transport Pattern on Beaches in the Gulf of Arauco, Chile, to Assess Morphological Shoreline Evolution. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 656–660. Coconut Creek (Florida), ISSN 0749-0208. Coastal evolution is an important research topic worldwide and has become increasingly relevant due to growing anthropogenic pressure on the coast and a climate change scenario (Masselink et al., 2016). The Gulf of Arauco covers an area of roughly 40,000 km2 and has a sandy-rocky coastline located in a very seismic environment. The area has suffered several major earthquakes during the last century (Valdivia 1960, Maule 2010) and seismic displacement has widely affected the coastline (Béjar-Pizarro et al., 2010). Despite these findings, the morphological evolution of sandy coastlines is mainly caused by wave-driven littoral processes. In this paper, using numerical modeling (Delft3D), we aim to characterize the longshore sediment transport (LST) direction at several spots (7 beaches) spread along the coastline of the Gulf of Arauco. Wave patterns were identified at each study site, revealing the importance of Santa Maria Island, located at the entrance to the gulf, despite the approach direction of deep water waves. The island acts as a moderator of wave patterns, softening the highly energetic swell that comes from the Antarctic Ocean and sorting the wave propagation inside the gulf. Moreover, LST patterns were characterized at each site for dominant wave conditions (SW swell and NW winter storms) and it was possible to explain how each condition has a different response at each spot, even under similar co-seismic displacements. Adaptation capabilities differ from site to site, suggesting a dynamic equilibrium of beaches in the area. [ABSTRACT FROM AUTHOR]

ABSTRACT Kim, M.J.; Kim, H.C.; Lee, W.C.; Park, J.M.; Kwak, S.N.; Oh, Y.; Kang, M.G., and Lee, S.H., 2018. Ecological characteristics of the new recorded seahorse in Geoje-Hansan Bay, Korea. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 351–355. Coconut Creek (Florida), ISSN 0749-0208. A basic ecological research of the seahorse populations has not been done to date even though the population is declining due to overfishing, by-catching and heavy human activities. Recently reported seahorse (Hippocampus haema) samples were monthly collected in Geoje–Hansan bay for a year from August 2015 to August 2016. Standard length (SL), weight (Wt), coronet height (CH), trunk length (TrL), and tail length (TaL) of each individual were measured for identifying characteristics of H. haema. The ranges of temperature and salinity were 8.2–26.0 °C and 29.3–34.1 ‰, respectively. Mean SL and Wt for all the groups were 55.26 ± 16.11 mm and 0.32 ± 0.25 g, respectively. There were significant differences in the relative ratios of each length factor (TrL, TaL and CH) and condition factors (CFs) according to gender or breeding period (ANOVA, p < 0.01). Since pregnant males constituted nearly 40 % (18 individuals) in May and juvenile seahorses were first observed in June, 2016, the recruitment of this species appears to begin in June. Based on our one-year field observation, the duration of the breeding season of the H. haema in Geoje-Hansan bay can be estimated for approximately 7 months long which is similar to other seahorse species (generally 4 to 10 months) inhabiting similar latitudes. The results from this study provide important information for a sustainable management and conservation of the new recorded seahorse species. [ABSTRACT FROM AUTHOR]

ABSTRACT Ha, H.J.; Choi, S.M.; Seo, J.Y., and Ha, H.K., 2018. Erodibility of sand-mud mixed sediment on the Yeochari tidal flat, Gyeonggi Bay, Korea. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 416–420. Coconut Creek (Florida), ISSN 0749-0208. Yeochari tidal flat is located along the southwestern part of Ganghwa Island in Gyeonggi Bay. The aim of this study is to quantitatively evaluate the erodibility of sediment on the tidal flat. Sediment samples were obtained from two typical sites (mud and mixed flats) in April and June, 2017, and then their erodibilities were estimated by a Gust erosion microcosm system. Erodibility at the two sites was different in April and June. In April (late spring), the total eroded mass of mud flat was 0.023 kg m−2 with clay content of higher than 10%, whereas total eroded masses of mixed flat were 0.027 to 0.029 kg m−2 with clay content of lower than 5%. Thus, the sediment erodibility in mud flat was lower than that in mixed flat during April due to clay content. As the clay content increases, non-cohesive sediments were likely surrounded by cohesive sediments. This induced to enhance the inter-particle bonding and decrease the erodibility. In June (early summer), although the clay content was less than 5%, the mixed flat had the low erodibility (total eroded mass of 0.004 kg m−2), which was about 7 times lower than that in April. The low erodibility in June might be caused by the enhanced armoring effect with increased grain size. [ABSTRACT FROM AUTHOR]

Lim, J.-H.; Lee, S.H.; Park, J.; Lee, J.; Yoon, J.-E., and Kim, I.-N, 2018. Coastal Hypoxia in the Jinhae Bay, South Korea: Mechanism, Spatiotemporal Variation, and Implications (based on 2011 survey). In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 1481–1485. Coconut Creek (Florida), ISSN 0749-0208. Hypoxia (dissolved oxygen ≤2 mg L−1), which occurs frequently in coastal regions due to eutrophication, is a serious environmental problem in marine ecosystems. The areal extent of hypoxic regions has increased globally in recent decades. Jinhae Bay (JB) on the southeastern coast of South Korea has suffered from seasonal hypoxia due to increased anthropogenic activities since the 1970s. However, no intensive study has examined hypoxia in JB, although it is a scientific, social, and economic concern. We conducted monthly hydrographic surveys of JB in 2011 and present the mechanism of the hypoxia and its spatiotemporal variation there. The advent of hypoxic waters in the JB was initiated locally by the combination of developing stratification and increased benthic (bottom waters + sediments zone) remineralization in early June. From mid-July to early September, the hypoxia extended to the entire region, despite constant organic matter content in the benthic layer, due mainly to strong stratification, resulting in stagnant water circulation. During September, the hypoxia was maintained by a combination of physical and biogeochemical effects, although the areal extent of the hypoxic regions was substantially reduced. Overall, the hypoxia was present from early June until late September, with monthly spatiotemporal variation. The hypoxic waters tended to have low pH values, indicating an association with coastal acidification. JB, a small coastal region, suffers from serious environmental problems that urgently need our attention. [ABSTRACT FROM AUTHOR]

Lee, J.H.; Kim, H.C.; Lee, T.; Lee, W.C.; Kang, J.J.; Jo, N.; Lee, D.; Kim, K.W.; Min, J.-O.; Kang, S., and Lee, S.H., 2018. Intracellular nutrient pools in the Jaran Bay, South Korea. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 331–335. Coconut Creek (Florida), ISSN 0749-0208. It is important to understand intracellular nutrient pools of phytoplankton as a major nutrient remover in coastal areas. The water samples for intracellular nutrient concentrations (ammonium, nitrite + nitrate, phosphate, and silicate) of different sizes phytoplankton and nutrient conditions in ambient water column were monthly obtained in a southern coastal area of Korea, Jaran Bay from February to December 2016. The intracellular nutrients of phytoplankton were extracted by the method of osmotic shock combined with heating. The intracellular nutrient concentrations during this study were 0.35–1.79, 0.19–12.63, 0.01–0.40, and 0.54–9.21 μM for ammonium, nitrite + nitrate, phosphate, and silicate, respectively. In comparison, the water column nutrient concentrations were 0.26–12.00, 0.05–14.39, 0.002–1.26, and 1.43–48.33 μM for ammonium, nitrite + nitrate, phosphate, and silicate, respectively. The contributions of micro-sized (> 20 μm) phytoplankton and pico-sized (0.7–2 μm) phytoplankton accounted for 48.2% and 22.7% of the total chlorophyll a concentration, respectively in this study. The intracellular nutrient concentration per unit of chlorophyll a concentration had a negative relationship with the chlorophyll contribution of micro-sized phytoplankton. This result suggests that larger phytoplankton are appeared to store less intracellular nutrient pools than smaller phytoplankton. This is related to the characteristics of dominant phytoplankton species in Jaran Bay such as Chaetoceros debilis and Chaetoceros affinis which normally accumulate small amounts of intracellular nutrients compared to small phytoplankton. Based on this result, nutrient dynamics in marine ecosystems especially for coastal areas would be different under ongoing larger contributions of small phytoplankton in warming ocean conditions. [ABSTRACT FROM AUTHOR]

Wilson, T. and DePaul, V., 2017. In situ benthic nutrient flux and sediment oxygen demand in Barnegat Bay, New Jersey. In: Buchanan, G.A.; Belton, T.J., and Paudel, B. (eds.), A Comprehensive Assessment of Barnegat Bay-Little Egg Harbor, New Jersey. The U.S. Geological Survey, in cooperation with the New Jersey Department of Environmental Protection, measured sediment oxygen demand (SOD) and benthic nutrient fluxes throughout Barnegat Bay, New Jersey. SOD was determined in situ using chambers equipped with optical dissolved oxygen sensors. The benthic nutrient fluxes of ammonia (NH3), nitrite + nitrate ( plus ions; here, referred to as NO32), soluble reactive phosphorous (SRP), and dissolved silica (SiO2) were measured with in situ equilibrium dialysis samplers. Measurements were made at nine stations around the periphery and at three mid-Bay locations from August 2012 to October 2013. The SOD ranged from −1.5 to −8.4 g of oxygen (O2) m−2 d−1. The SOD rates varied as a function of water temperature and followed the van't Hoff rate equation for change in reaction rate with temperature, with a temperature coefficient ( Θ) that varied among sites and averaged 1.083. The highest SOD rates in the bay were measured near the mouth of the Toms River embayment. Concentrations in the upper 1 m of sediment pore water were found up to 23 mg N L−1 for NH4+ and 6.7 mg P L−1 for SRP. Maximum measured fluxes into the overlying water were 3.0 × 10−2 g NH3-N m−2 d−1, 7.0 × 10−4 g NO32-N m−2 d−1, 1.9 × 10−3 g P m−2 d−1, and 3.6 × 10−3g SiO2 m−2 d−1. Using the measured benthic N and P fluxes, daily nutrient inputs derived from sediment recycling are shown to be comparable in scale to freshwater tributary inputs to the bay. [ABSTRACT FROM AUTHOR]

Ren, L.; Belton, T.J.; Schuster, R., and Enache, M., 2017. Phytoplankton index of biotic integrity and reference communities for Barnegat Bay-Little Egg Harbor, New Jersey: A pilot study. In: Buchanan, G.A.; Belton, T.J., and Paudel, B. (eds.), A Comprehensive Assessment of Barnegat Bay-Little Egg Harbor, New Jersey. A pilot study was carried out to quantify season-salinity-specific phytoplankton reference communities and to develop a phytoplankton index of biotic integrity (P-IBI) for Barnegat Bay-Little Egg Harbor (BB-LEH) estuary, using approaches similar to those for the Chesapeake Bay. Synchronized phytoplankton and water-quality data collected between August 2011 and August 2013 from the Barnegat Bay Water Quality Monitoring Program were used as calibration data set. The results showed that one-fifth of samples were from the least-impaired habitat condition, with low turbidity and low concentrations of dissolved inorganic nitrogen and orthophosphate (PO4). Nearly 60% of samples were from undesirable conditions with poor water clarity and excess nutrients. Phytoplankton reference communities, in comparison with communities in impaired conditions, were characterized with low concentrations of chlorophyll a (Chl a), total nitrogen (TN), and total phosphorus (TP), low Chl a/C ratio, low summer picoplankton biomass, and high spring and summer dissolved oxygen. Thirty-four metrics were evaluated for their ability to discriminate between the least-impaired and impaired habitat conditions. Nine phytoplankton metrics and three physiological and chemical metrics, which showed strong discriminatory ability, were selected, and different combinations of these metrics were used to create phytoplankton indices for spring and summer mesohaline and polyhaline zones in BB-LEH. The current P-IBI was able to correctly classify 64-100% for spring samples and 68-88% for summer samples in the calibration data set. Our work is the first attempt to develop a P-IBI for this region. The calculated reference communities and P-IBI, though constrained because of limited data availability, were region specific and intended to facilitate water-quality assessment and management efforts in BB-LEH. The differences of TN and TP between the least-impaired and impaired conditions in most of season-salinity zones suggested that dual reduction of N and P are necessary to control eutrophication in BB-LEH. Further work on the refinement of the P-IBI is underway as additional phytoplankton and water-quality data are being collected and assessed. [ABSTRACT FROM AUTHOR]

Vasslides, J.M. and Jensen, O.P., 2017. Quantitative vs. semiquantitative ecosystem models: Comparing alternate representations of an estuarine ecosystem. In: Buchanan, G.A.; Belton, T.J., and Paudel, B. (eds.), A Comprehensive Assessment of Barnegat Bay-Little Egg Harbor, New Jersey. As the management of marine and coastal resources continues to move toward an ecosystem-based approach, there is a need for tools that can match the scope and complexity of the systems in question. This article contrasts the strengths and weaknesses of two types of models that can be used to understand ecosystem-level changes: Ecopath with Ecosim, a whole-ecosystem trophic-based quantitative model, and a semiquantitative fuzzy cognitive mapping conceptual model developed by local stakeholders. It also compares the modeled results of reducing nutrient loads to a temperate estuary to understand how the different approaches can be best utilized to meet the needs of resource managers. Both models responded to the nutrient load reduction in a similar fashion, despite the differences in data sources, approaches, and methodology. This congruence between the two methods most likely reflects a shared conceptual understanding of the ecosystem between scientists and stakeholders. The largest benefit from the strengths of both models is gained by using them in combination; the fuzzy cognitive mapping model can scope out critical components and interactions to be included in the Ecopath with Ecosim model. The latter model can then be parameterized and 'what-if' scenarios run to ascertain the patterns and magnitudes of changes that can be expected. [ABSTRACT FROM AUTHOR]

Guo, J.; Yu, K.; Wang, Y.; Xu, D.; Huang, X.; Zhao, M.; Yang, H., and Zhang, R., 2017. Nutrient distribution in Coral Reef degraded areas within Sanya Bay, South China Sea. An investigation was conducted in August 2014 to explore the spatial distribution of dissolved inorganic nitrogen (DIN) and phosphate ( ) in overlying water, pore water, and surface sediment from Sanya Bay and living coral cover on Luhuitou fringing reef. Generally, nutrient contents gradually decreased from the estuary to the central bay, which confirmed that terrigenous inputs from Sanya River and Sanya Harbor were the primary nutrient sources. The results of K-means cluster analysis suggested the Luhuitou fringing reef is in danger of being affected by the pollution source. The results of nutrient diffusive fluxes at the sediment-seawater interface indicated diffusion from pore water to overlying water. Compared with other coral reef areas around the world, nutrient levels in Luhuitou fringing reef were at the medium level. Significant correlation between temporal variation of nutrients and living coral cover was not found, which suggests that low nutrient enrichment, ranging from 1.89 to 2.89 μmol/L for DIN and from 0.1 to 0.49 μmol/L for , may not be responsible for the coral reef decline on Luhuitou fringing reef from 2002 to 2014. [ABSTRACT FROM AUTHOR]

Lee, J.; Kim, S.-g., and An, S., 2017. Dynamics of the physical and biogeochemical processes during hypoxia in Jinhae Bay, South Korea. Bottom-water hypoxia occurs during the summer in Jinhae Bay, a semienclosed embayment in South Korea, and can have detrimental effects on marine ecosystems around the region. Measurements of the oxygen demand in the bottom water and sediments and time-series measurements of hydrographic characteristics were conducted in Jinhae Bay in 2015. Variations in dissolved oxygen (DO) can be divided into three distinct time periods. During period I (late March to late May), bottom DO decreased linearly with thermocline development. During period II (late May to late August), hypoxia persisted. During period III (after late August), bottom DO increased as the thermal stratification began to break down. The seasonal bottom-water oxygen concentration was significantly correlated with the temperature difference between surface and bottom water, indicating that hypoxia development and maintenance is strongly dependent on thermal stratification. Although high oxygen demand in the water column and sediments must affect summer bottom-water hypoxia, biogeochemical oxygen consumption may not be significantly correlated with the time of formation and dissipation of hypoxia. The sediment oxygen demand was comparable with the water-column oxygen demand (WOD) in period I, whereas WOD dominated the total oxygen demand in the bottom water in period II, indicating that water-column respiration played a major role maintaining the hypoxic conditions. The results suggest that physical processes, especially thermal stratification, are more important to the development of hypoxia than biogeochemical oxygen consumption in Jinhae Bay, where freshwater input is insignificant and water circulation and exchange with the outer bay are restricted. [ABSTRACT FROM AUTHOR]

Eom, J.; Choi, J.-K.; Won, J.-S.; Ryu, J.-H.; Doxaran, D.; Ruddick, K., and Lee, S., 2017. Spatiotemporal variation in suspended sediment concentrations and related factors of coastal waters based on multispatial satellite data in Gyeonggi Bay, Korea. The variations in suspended sediment concentration (SSC) in turbid coastal waters around Gyeonggi Bay, Korea were analyzed using multiresolution ocean-color satellite imagery. Geostationary Ocean Color Imager (GOCI) and Land Satellite 7 (Landsat-7) Enhanced Thematic Mapper Plus (ETM+) images were atmospherically corrected, and an empirical algorithm was employed to generate maps of SSCs in the study area and investigate daily and annual variabilities in coastal water turbidity. SSC values were highest around 6 hours before high tide and around low tide, and the maximum values had strong positive relations with the tidal range near the sand ridge and channel ( R2 values of 0.74 and 0.72, respectively), which implies that the main driver of the diurnal variability in SSC is resuspension of bottom sediment by tides in areas of shallow water. Annually, the maximum SSC value near the sand ridge was about 400 g m−3, showing remarkable variation over tidal cycles, whereas it was about 10 g m−3 in the open sea, with little variation. The SSC around the sand ridge was higher in winter than in summer, mainly because of stronger resuspension resulting from winds during the NW monsoon in winter. The SSC around the Han River estuary was higher in summer than in winter because of the river discharge, which indicates that suspended sediments supplied by the Han River do not significantly affect SSC variation in the open ocean. This study revealed that application of the high temporal resolution of GOCI, combined with the high spatial resolution of Landsat-7 ETM+, can be useful for monitoring short- and long-term variations in SSC in Korean coastal waters. [ABSTRACT FROM AUTHOR]

Pantoja, D.A.; Marinone, S.G., and Filonov, A., 2017. Modeling the effect of a submarine canyon on eddy generation in Banderas Bay, México. Banderas Bay is located at the tip of Cabo Corrientes, a coastal promontory near the entrance of the Gulf of California. In this area, the intensification and recirculation of the Mexican Coastal Current (MCC) interact with Banderas Bay and, more specifically, a submarine canyon within the bay, in a manner that generates eddies. This eddy formation was explored using the Regional Ocean Modeling System (ROMS) numerical model in a series of idealized experiments consisting of a northward coastal current simulating the MCC. Banderas Bay is prone to generate eddies due to a headland and the very steep topography of the canyon. When the intensity of the currents at the entrance of the bay reaches 0.4 m s−1, the circulation exhibits detachments and then eddies. The eddies have azimuthal speeds of 0.1 to 0.3 m s−1 and diameters that are constrained by the bay/canyon geometry of up to 30 km. Dynamically, the Froude number is Fr ∼ 0.4, and the Rossby number (Ro) is >0.65, leading the Burger number (Bu = Ro2/Fr2) to be ∼2, showing that the eddy shedding is due to a separation process. These eddies are generated at the lee of the cape and shed to the center of the bay. As a result of the MCC intensification, the advection of vorticity is more intense, by ∼15%, than the vertical stretching mechanism (which is commonly more significant in canyon dynamics). In addition, as the canyon narrows with depth, the dynamics change from a gradient-flow balance in the upper layers to less of a gradient-flow balance in the deeper layers, where the pressure gradient force dominates the circulation. [ABSTRACT FROM AUTHOR]

de la Lanza-Espino, G.; Silva, R.; Hernández-Pulido, S.; Mariño-Tapia, I., and Enríquez, C., 2017. A retrospective analysis of water quality in an open bay on the Mexican Pacific. In: Martinez, M.L.; Taramelli, A., and Silva, R. (eds.), Coastal Resilience: Exploring the Many Challenges from Different Viewpoints. Journal of Coastal Research, Special Issue, No. 77, pp. 39-50. Coconut Creek (Florida), ISSN 0749-0208. Lack of knowledge about the complex interactions between the dynamics of natural systems (physical, chemical and biological) and the need for the resources found in coastal environments has led to the unplanned and disorganized development of several anthropogenic activities in the study area. It is important to revert this tendency and promote medium term studies that can help to foresee the unwanted effects, sometimes irreversible, of human activities on the environment. This paper includes results from hydrodynamic and water quality studies carried out in Petacalco Bay, Guerrero (Mexican Pacific) in order to present elements for future appropriate management of industrial outflows in the region. Around this bay there are important rivers and small villages, a major port, chemical and thermoelectric plants, all discharging their (generally untreated) effluents directly into the sea. The results of this study show that the overall water quality is similar to natural concentrations found in the ocean. Nevertheless, eutrophization was found, associated with the fertilizer industry, and the hot water discharge from the thermoelectric plant generates hot plumes, which dissipate in the environment, despite the intense and variable hydrodynamic characteristics of the region. [ABSTRACT FROM AUTHOR]

Palinkas, C.M.; Barth, N.; Koch, E.W., and Shafer, D.J., 2016. The influence of breakwaters on nearshore sedimentation patterns in Chesapeake Bay, USA. This study describes nearshore Chesapeake Bay sedimentation at sites adjacent to and landward of 24 segmented breakwaters, varying in age (1-19 years) and physical setting. Grain-size and organic-content profiles are examined at the breakwater-protected sites to assess potential changes induced by breakwater installation as well as at the adjacent-exposed sites to establish historical trends. Sedimentation rates at all sites are calculated with 210Pb (half-life 22.3 years). At the breakwater-protected sites, these rates largely reflect preconstruction sedimentation because of the long half-life of 210Pb relative to breakwater ages. Determining the postconstruction sedimentation rate can be more difficult because the signature of breakwater influence in the sedimentological record can be obscured. For example, if the source of sediment is not affected dramatically by construction, down-core profiles may not have obvious changes. The depth of breakwater influence, however, can be interpreted by considering all the sedimentological evidence at a given location, and the postconstruction rates are calculated from this depth. In general, the sedimentological response to breakwater construction is fairly unique for each location but depends on such factors as breakwater age and geometry, shoreline sediment composition, and construction technique. [ABSTRACT FROM AUTHOR]

Montes, J.M.; Lavín, M.F., and Parés-Sierra, A.F., 2016. Seasonal heat and salt balance in the Upper Gulf of California. The salinity and heat balance, as well as the seasonal variation of the average absolute salinity (〈 SA〉) and conservative temperature (〈 Θ〉), were described by using data from 24 cruises within four domains in the Upper Gulf of California (UGC). Monthly values of SA and Θ, and surface fluxes obtained from ERA-Interim reanalysis data sets were fitted to a seasonal signal, and the horizontal fluxes of salinity and heat content were calculated by using balance equations. The UGC exports salt and heat to the Northern Gulf of California (NGC) almost all year, with an annual mean of 1.6 g/kg per year for the salinity flux and 0.16 terawatts (TW) for the heat flux. The results suggest that the net excess of evaporation (∼0.8 m/y) and heat gain by the surface (∼70 W/m2) are the main factors controlling the exchange of salinity and heat between the UGC and the NGC. To help identify the relevant dynamic factor involved in the heat and salinity balances, a high-resolution numerical model, the regional ocean modeling system (ROMS), was implemented for the region. The main feature of the UGC circulation consists of a cyclonic surface flow that extends downward as a laterally sheared flow pattern, with inflow at the Sonora coast side and outflow at the Baja California coast side. Although the cyclonic circulation pattern remains most of the year, the maximum velocities (∼0.20 m/s) are reached in June. The results indicate that the major exchange between the UGC and the NGC occurs in June and July when the net volume transport (∼0.9 Sverdrups) is dominated by the horizontal overturning transport. [ABSTRACT FROM AUTHOR]

Wang, F.; Zong, Y.Q.; Li, J.F.; Tian, L.Z.; Shang, Z.W.; Chen, Y.S.; Jiang, X.Y.; Yang, J.L.; Yang, B., and Wang, H., 2016. Recent sedimentation dynamics indicated by 210Pbexc and 137Cs records from the subtidal area of Bohai Bay, China. To determine sedimentation rate changes across an open marine area along the west coast of Bohai Bay, more than 50 short sediment cores were collected and analyzed with their sedimentation rates estimated by excess 210Pb (210Pbexc) and 137Cs in the sediment. The surveys enabled us to explore the relationship between sediment supply changes from the rivers and the spatial/temporal deposition patterns in the shallow marine areas. Several core records show that sedimentation rates can be overestimated by the conventional constant initial concentration model based on the 210Pbexc curves alone. The overestimation was caused by a change of 210Pbexc in the top layers of these cores and this is confirmed by comparing 210Pbexc curves with the respective 137Cs curves. This phenomenon is likely caused by sediment erosion or redeposition of the surface sediment at the seabed, implying present-day active sedimentary processes as a result of the drastic decrease in sediment supply from the rivers during the last 50 years. The sedimentary boundary where sedimentation rate changed is largely comparable with the timing of sediment supply change according to the river discharge data, which can be used as a local time marker for sedimentation rate comparison. [ABSTRACT FROM AUTHOR]

Numanoğlu Genç, A., 2015. A model to simulate yacht movements in enclosed bays. In this article, a computer model developed to simulate the movements of yachts (boats) in enclosed bays is discussed. The computer model uses multinomial logit model to find the probabilities for the boaters to select the next bay to visit. The model predicts the number of boats in each bay at the end of a day, the number of boats that visited each bay during the day, and the distribution of boater categories among the bays throughout the simulation time. As a case study, the model is applied to Göcek bays located at the west Mediterrnean coast of Turkey. To obtain the input data, a questionnaire was formed, and a detailed survey was carried out in Göcek bays. In addition to the questionnaires, the number of the boats anchored in the bays were observed in the field studies. The results obtained by the model are compared with the data obtained in the field. Comparisons show that the yacht movements and distributions at various anchor locations can successfully be predicted with the model. This model can be used as an effective tool in the management of coastal areas. Bu makalede, yatların hareketlerini inceleyen bir öykünüm modeli geliştirilmiştir. Yatçıların koy seçimlerindeki olasılıkları belirleyebilmek için matematiksel model olarak çok terimli logit model kullanılmıştır. Geliştirilen öykünüm modeli gün sonunda her koydaki tekne sayısını, gün içerisinde koylara girip çıkan tekne sayısını ve tüm öykünüm süresi için yatçı gruplarının koylara dağılımını hesaplamaktadır. Bu model için gerekli olan girdileri elde edebilmek amacıyla, Göcek Koylarında kapsamlı bir anket çalışması yapılmış ve ayrıca koylardaki tekne sayıları farklı zamanlarda gözlemlenmiştir. Bu öykünüm modelini baz alan bilgisayar programı Göcek Koylarına uygulanmış ve model sonuçları, saha incelemelerinden elde edilen veriler ile karşılaştırılmıştır. Gelecek yıllar için daha çok sayıda yatın bulunacağı durumlarda, bu modelin yardımıyla dağılım tahminleri yapılabilecektir. Bu tahminler yat trafiğinin ve konaklamanın denetlenmesini amaçlayan bir yönetim planı çerçevesinde yararlı bir araç olacaktır. [ABSTRACT FROM AUTHOR]

Kämpf, J. and Ellis, H., 2015. Hydrodynamics and flushing of Coffin Bay, South Australia: A small tidal inverse estuary of interconnected bays. Using a three-dimensional hydrodynamic model and the concept of water age, this study explores the hydrodynamics and flushing characteristics of Coffin Bay, South Australia, which is a small inverse estuary of interconnected bays. Model findings suggest that the estuary is mainly tidally flushed throughout the year. Despite the existence of strong tidal flows >1 m/s in passages between bays of the estuary, the resultant tidal stirring zones are largely disconnected from each other. This disconnection induces a relatively slow flushing of the estuary's inner bays, where maximum water ages are 80-100 days. Given the tidal dominance in the flushing dynamics, a simple diffusion equation based on a total effective transverse diffusivity D (estimated from the model predictions) can be used to describe the flushing behaviour of the estuary. This equation is applied to derive the thermal response of Coffin Bay to either temperature variations in ambient shelf water or changes in surface heat fluxes. Findings indicate that, on timescales of 30 days, the inner bays of Coffin Bay respond predominantly to changes in surface heat fluxes, whereas the outer bay is more responsive to temperature variations in ambient shelf water. We quantify these individual responses in terms of spatially variable 'thermal response factors,' which are fundamental properties inherent in the estuary's flushing dynamics. [ABSTRACT FROM AUTHOR]

The present study aims to identify factors that control the different morphological evolution of two sections of an urban beach. The study area is the Victoria Beach in Cadiz city (SW Spain). The beach comprises two sectors: Cortadura zone (CZ) and Victoria zone (VZ), both subject to the same offshore wave conditions. The area is a typical low energy coast with dissipative beach morphology, where storm conditions are generally recorded in the winter season. Variability of beach profiles was analyzed through the use of empirical orthogonal functions (EOF). For short-scale processes, nearshore wave and current measurements were collected simultaneously at both zones during a tidal cycle. Additionally, medium term beach evolution from the last 50 years was evaluated using aerial photos. Results of medium term beach changes show a clear retreat that in fact led to several artificial nourishments of the beach over the last years. Erosion observed in CZ was greater than in VZ. In the short term, VZ presented greater morphological variability than CZ, which only experienced some changes in beach volume. Wave and current measurements showed a higher wave height and longshore current velocity in CZ under the same offshore wave conditions, which might account for the higher erosive trend in this area and development of a more dissipative profile. The reason for this differential behavior is related to the different characteristics of wave propagation in the outer surf and shoaling zone of both sections. [ABSTRACT FROM AUTHOR]

Ren, H.; Guo, Q.; Liu, H.; Li, J.; Zhang, Q.; Xu, H., and Xu, F., 2014. Patterns of alien plant invasion across coastal bay areas in southern China. An understanding of the ways in which levels of invasions by alien species are correlated with environmental factors is helpful to manage the negative impacts of these invasive species. Two tropical coastal areas in South China, Shenzhen Bay and Leizhou Bay, are national nature reserves, but they are threatened by invasive plants. Here, we investigated the level of invasion by exotic plants at both bays, and its relationship with selected environmental factors. We found a total of 34 invasive plant species, 18 of which were present at both bays; among these, 15 species were in terrestrial areas, three were at the ecotone, and one was in the mangroves. The two bays had a similar degree of invasion but were dominated by different species. Three invasive species ( Ipomoea purpurea, Wedelia trilobata, and Panicum repens) were abundant at both bays, and only one species, Sonneratia apetala, was present in the mangroves. The number of alien species increased from mangrove to ecotone to terrestrial areas in both bays, while, in proportion, ecotone supported the most alien species in Shenzhen Bay. The relationships between plant invasion and habitat features depended on the variables that were used to measure the degree of invasions. In general, the occurrence of alien species was positively correlated with soil organic carbon and total N content but negatively correlated with the leaf area index and soil salinity. The biomass of alien plants was, on the other hand, positively correlated with total N and soil water content in the soil, and the density of alien plants was not correlated with habitat characteristics. Most of the alien plants originated from tropical America, but a few were from Africa and south Asia. We recommend restoration efforts that include removal of alien species, soil improvement, and the planting of native species. [ABSTRACT FROM AUTHOR]

Sustainability of coastal aquatic resources is deeply associated with several hydrophysical processes, where internal tide is one of the key processes. Seasonal variation in the characteristics of the internal tidal currents and their associated change in water temperature was observed to take part in managing the coastal aquatic systems in Genka Bay, Okinawa, Japan. Profiling and mooring measurements were carried out in three sites of the study area during summer and winter. The study results show that the depth-averaged current flows nearly parallel to the coastline during summer and winter. There is also an existence of a cross-shore internal tidal current according to the vertical structure of the horizontal current in both seasons. This current influences the bottom water temperature transmission from offshore to nearshore bottom water and changes the vertical temperature profile even of nearshore regions and thereby establishes a unique cooling system. This influence is stronger in summer than in winter due to the seasonal variations in the intensity of the propagated internal tidal currents. Spectra of the baroclinic and bottom water temperature confirm the existence of the semidiurnal constituent-dominated internal tides as well as their seasonal and shoreward variations in Genka Bay. [ABSTRACT FROM AUTHOR]

The present marine transgression has forced geological and ecological zones vertically higher and landward since the late Pleistocene. A recent investigation in Duxbury Bay, Massachusetts, identified 18 Juniperus virginiana tree stumps emergent on an intertidal flat immediately seaward of a small marsh and pond situated between two eroding drumlins. The position of each stump was mapped with global positioning system (GPS), and its elevation with respect to mean lower low water was surveyed. Samples were selected from four stumps with elevations ranging from 2.03 and 0.75 m above mean lower low water for radiocarbon dating. The samples returned calibrated ages between 2219 ± 94 and 2867 ± 79 cal YBP, with the topographically highest sample returning the youngest date. Stump positions suggest a landscape gradient of 1.4 mm/yr between 2000 and 3000 cal YBP. The results are comparable with high-resolution studies of sea level in eastern Massachusetts for the same time period. Comparison of the youngest paleostumps with modern living trees suggests a dramatic change in the landscape gradient, an increase to 1.8 mm/yr. While this is contrary to sea-level studies nearby, it may represent an increase in the energetics of Duxbury Bay and resultant coastal erosion as the bay floods. The site can be used to put the impacts of changing sea-level rates into a landscape evolution framework. [ABSTRACT FROM AUTHOR]

Changes in land use and cover influence surface water quality and thus are a potential threat to water systems and coastal ecosystem health. The objectives of this study were to evaluate the influence of historical land use-land cover (LULC) changes and point-source sewage discharge on surface water quality of some lower Eastern Shore watersheds of Maryland. LANDSAT data for 1986-2006 was acquired and classified using Anderson level-1 classification system in ENVI 4.5, whereas LULC changes were detected in Arc-GIS 9.2 environment. Historical water monitoring and climatic data were obtained from Maryland Department of Environment-Chesapeake Bay Program, and National Oceanic and Atmospheric Administration, respectively. Nutrient loading data from wastewater treatment plants were obtained from Maryland Department of Environment and data analyzed using regression analysis and principal component analysis (PCA). The result shows that total phosphorous levels in the surface waters decreased significantly (p , 0.05) during the 20-year study period. However, using PCA, we determined that the declining P trend was attributable to the decreasing agricultural land use rather than the sewage discharge from wastewater treatment plants. The increase in urban land use and the resultant runoff to the water bodies may explain the declining trends in dissolved oxygen levels observed during the period, with serious implications for eutrophication. An empirical model developed for P in surface waters (r2 5 0.90) showed that the combination of point and nonpoint sources and land use/cover change factors are good predictors. The incorporation of quantitative LULC data component as well as point-source nutrient loading into existing models is highly recommended for a more holistic assessment of land-use influence on water systems in general. [ABSTRACT FROM AUTHOR]

Bezerra, M.O.M.; Freitas, P.P.;Baltazar, L.R.S.; Rollnic, M., 2013. Estuarine processes in macro-tides of Amazon estuaries: A Study of Hydrodynamics and Hydrometeorology in the Marajo Bay (Pará-Brazilyn: Conley, D.C., Masselink, G., Russell, P.E. and O'Hare, T.J. (eds.) The work carried out a hydrodynamic and hydrologic characterization in the estuary of the Para River (Marajó Bay), near the Colares and Guaras Islands (pará, Brazil). The goal is to verify the behavior of the semi-diurnal macro-tide in large Amazon estuaries with an emphasis on hydrodynamic and hydrological characterization of the pará River estuary. The work proposed as targets; to investigate the hydrodynamics as to stream and water level, and the physicochemical variations of the water body. The studies were conducted in quadrature and consisted of measurements of streams, salinity, temperature and tidal range. The main results showed that the pará River estuary, as to the hydrological characteristics of the system, showed no significant variations in salinity throughout the water column in most profiles during the surveys. However, in Colares, there was an increase in the salinity over time, ranging from 3 to 5. On the Island of Guarás, the salinity was around 4 in the entire water column. The temperature in both, Colares and Guarás, did not vary, it was always 29°C. These results show that, even during the drought period, with low flow, the effect of river water is one of the main forces of circulation, and even more important than mixing processes generated by the tide. As to the hydrodynamic characteristics of the system, it was found that stream direction during sampling varied widely, and was usually followed by low speeds. Overall, the estuary shows circulation of a very mixed kind, being mainly controlled by river discharge and secondarily by the oscillations of the tide. It is important to continue studies in this region, because the estuarine processes in macro-tides of Amazon estuaries are complex and do not have characteristics in common with other macro-tides estuaries due to the great flows of rivers in the Amazon region. [ABSTRACT FROM AUTHOR]