Search

With rising sea level and climate change, coastal protection against natural hazards such as typhoons and storm surges becomes increasingly important in densely populated areas. Yet, how to integrate necessary engineering structures for coastal protection with development of a healthy socio-ecological system represents a realistic question challenging both the science community and practitioners. This study is motivated to examine the role and influence of diverse dimensions in the construction of seawalls for coastal protection and sustainability. Focusing on a case along the Qiantang River in China, we structured an indicator framework based on technical standards and literature for guiding the design and construction of ecological seawalls. We explored and illustrated the application of a multi-criteria decision making (MCDM) method to analyze proposed indicators as design factors and their influence in practice as reflected by expert evaluation. Our empirical analysis revealed a heterogeneous role and influence of different indicators and their asymmetric interaction in seawall construction aimed to deliver structural safety, ecological functions and social development. This study provides important insights into the design and management of seawalls as an integrated, nature-based solution for coastal protection and sustainability, informing practice improvement and contributing to the literature. [ABSTRACT FROM AUTHOR]

Existing seawalls along the eastern coast of China are increasingly becoming the focus of upgrade operations. Concerns arise regarding the settling and stability of seawalls built on soft clayey seabed during upgrade operations. Pore water pressure (PWP) and horizontal displacement accumulations induced by combined tide and wave loadings are observed in in-situ measurements of the clayey seabed underneath the seawall. The measurement results show clear correlations between the oscillations of excess PWP and variations in the tidal height. To reproduce the quasi-static interaction behaviors of the gravity-type seawall and clayey seabed under combined cyclic loadings from waves and currents, a finite element model has been built after incorporating a stiffness degradation law that is evaluated from laboratory triaxial tests on the seabed soil. Demonstrably, with a suitable stiffness degradation law for the seabed soil, the accumulative behaviors can be reasonably reproduced using finite-element modeling. [ABSTRACT FROM AUTHOR]

Sea cucumber Apostichopus japonicas (Selenka) is one of the important aquaculture species distributed in northern China. In recent years, global warming caused frequent high temperature weather in summer in northern China, resulting in dramatic losses of the sea cucumber aquaculture industry. In the present study, we focused on the effect of oxidative stress in Apostichopus japonicus (Selenka) subjected to high temperature stress. Sea cumbers were exposed to the control (16 °C), and high temperature treatments (20 °C, 24 °C, and 28 °C) for 7 days. Then, reactive oxygen species (ROS) level, superoxide dismutase (SOD) activity, catalase (CAT) activity, peroxidase (POD) activity, reduced glutathione (GSH) content, malondialdehyde (MDA) content and 8-hydroxy-2′-deoxyguanosine (8-OHdG) level in the respiratory tree and body wall were detected, respectively. Results showed that 24 °C and 28 °C acute exposure induced the elevation of ROS level, SOD, CAT, POD activities, GSH content, MDA content and 8-OHdG level in the respiratory tree of sea cucumber. In contrast, no significant changes were observed for ROS and 8-OHdG levels in the body wall of sea cucumber, while the antioxidants including SOD, CAT, POD, and GSH decreased to some extent. Moreover, MDA content exhibited a noticeable increase in the body wall, similarly to that in the respiratory tree, indicating that high temperature could induce severe lipid peroxidation in two tissues. Considering the differences in various biomarkers measured in two tissues, respiratory tree might be more susceptible to the high temperature changes compared to the body wall. Our findings may help understand the oxidative stress response to high temperature in the respiratory tree and the body wall in A. japonicus. [ABSTRACT FROM AUTHOR]

Simple Summary: Coastal reclamation is the process of converting sea area to land. It is a land use practice commonly associated with loss and damage to the environment, pollution, and affecting the subsistence of man, animals, and plant life. In China, seawalls are constructed along the coastlines to transform wetlands into additional productive land. However, the construction of these seawalls comes with some negative environmental impacts. This study examined the impact of seawalls on the distribution of trace metal (TM) pollution in reclaimed and unreclaimed wetlands. Plant and soil samples were collected from the affected wetlands and analyzed in the laboratory. Results show that the construction of the seawalls, coupled with factors such as plant organic matter, soil water, and salt content influenced the significant increase in TM pollution in the reclaimed wetlands compared to the unreclaimed wetlands. A comparison of the results with international standard quality guidelines shows that the soils from wetlands on the coastline of the study region were moderate to severely polluted by copper, zinc, and chromium. Overall, soils affected by reclamation posed a greater ecological risk than in unreclaimed wetlands. Stakeholders can use this scientific outcome to mitigate TM pollution caused by seawall construction in coastal ecosystems. Coastal reclamation by seawall embankments and the spread of invasive C4 perennial grass Spartina alterniflora have recently become more prevalent in eastern China's coastal wetlands. While trace metals (TMs), carbon, and nitrogen dynamics concerning reclamation have extensively been explored across China's coastal wetlands, to date, the impact of reclamation by coastal embankment and exotic plant invasion on TMs' pollution dynamics in coastal marshes remains largely unexplored. We compared TMs Cr, Cu, Pb, and Zn cumulation in coastal embankment-reclaimed versus unreclaimed S. alterniflora and Phragmites australis saltmarshes in eastern China coastal wetlands. In both S. alterniflora and P. australis marshes, coastal embankment reclamation spurred an increase in Cr, Cu, Pb, and Zn concentrations by 31.66%, 53.85%, 32.14%, 33.96% and by 59.18%, 87.50%, 55.55%, 36.84%, respectively, in both marsh types. Reclamation also reduced plant biomass, soil moisture, and soil salinity in both plants' marshes. Our findings suggest that the impact of coastal embankment reclamation and replacement of native saltmarshes by invasive S. alterniflora had a synergistic effect on TM accumulation in the P. australis marshes, as corroborated by bioaccumulation and translocation factors. Reclamation by coastal embankments and invasive alien plants could significantly impair the physico-chemical properties of native plant saltmarsh and essentially weaken the accumulation of Cr, Cu, Pb, and Zn potential of the coastal saltmarshes. Our findings provide policymakers with an enhanced knowledge of the relationship between reclamation, plant invasiveness, and TM pollution dynamics in coastal wetlands, providing a baseline for attaining future goals and strategies related to the tradeoffs of various wetland reclamation types. [ABSTRACT FROM AUTHOR]

Species diversity shapes ecosystem services. Despite the advantages that this relationship has for pest management, few studies have investigated the links between infrastructure damage (i.e. the percentage amount of infrastructures infested by termites), species richness and the environment. Moreover, it is not clear that which proportion of species richness (total/functional‐dominant/common/rare) contributes most to infrastructure damage.We correlated termite species richness with termite infestation throughout 83 cities in Zhejiang Province, eastern China. Species were classified according to whether or not they fed on wood, and based upon their distributional range, whether they were common or rare. We analysed the relative importance and the direct/indirect effects of climate, vegetation, anthropogenic activities, and the species richness of four functional categories of termites on the damage levels of eight infrastructure types in populated (i.e. urban and rural building, green space and sea wall) and remote areas (i.e. ancient building, large‐old tree, agroforest and reservoir dam).Common species favoured populated areas, whereas rare species favoured remote areas. Common species, with preferences for deciduous vegetation, caused more damage to the infrastructures of populated areas. Rare species, with preferences for evergreen vegetation, caused more damage in remote areas. Reforestation project which emphasized evergreen trees increased the number of rare species but reduced the number of common species. Elevation and drought risk were positively correlated with rare species richness but neutrally with common species richness.Structural equation models showed that vegetation predominantly influenced infrastructure damage in populated areas via altering common species richness, whereas climate predominantly and directly influenced infrastructure damage in remote areas. Notably, elevation and drought risk were positively correlated with infrastructure damage especially in remote areas.Synthesis and applications. Termites cause global economic losses of 15–40 billion dollars per year. Our study reveals that managing city forests and green space, for example increasing the proportion of evergreen trees, is a sustainable means of suppressing common termites and thereby reducing infrastructure damage in populated areas. Conservation strategies, supported by regular inspections, will become increasingly important as climate change not only threatens the survival of less harmful rare species, but also increases infrastructure damage in remote areas. [ABSTRACT FROM AUTHOR]

The importance of coastal protection increases with the increase in coastal development. Soft and hard protection measures are the most used techniques; however, hard structures are still preferable. Hard structures are characterized by a long lifetime and high stability in rough sea states. Many innovative, environmentally friendly hard coastal protections measured have been proposed and used for specific applications. This research's main objective is to develop and check a new coastal structure, Corrugated Semi-circular Breakwater (CBW). This structure is modified from the Semi-circular Breakwater (SCBW), one of the hard protections used in Japan and China, to increase its efficiency in coastal protection and electricity generation. A comparative study between CBW and SCBW is carried out physically in a two dimensions wide wave flume with dimensions 1.2*1.2*40 m and numerically using the Flow-3D model. The study checked the effect of the structures in merged, semi-merged, and submerged conditions and increased structure permeability. The reflection, transmission, and dissipation coefficients are used as the efficiency indicators. The results show that CBW is more efficient in wave dissipation, current velocity reductions, and bed stability than SCBW. It is recommended to use the CBW as a submerged protected structure within the recreational coastal areas. [ABSTRACT FROM AUTHOR]

Coastal areas have been intensively urbanized in Asia, causing changes to the structure and function of intertidal macrobenthic communities. In this study, the intertidal assemblages on two natural rocky shores, two rocky shores disturbed by construction works, and two shores with mixed artificial seawalls and mudflats in the Dongtou Islands were studied. We examined the influence of coastal engineering by comparing macrobenthic community structures in different transects. The statistical results revealed significant differences between macrobenthic community structures in natural and influenced transects, although all the high tidal zones shared common species. The most common species on mudflats were opportunistic polychaetes; however, historical evidence suggests that the mudflats in Dongtou used to be dominated by Mollusca. We inferred that this change in community structure occurred when the seawalls were constructed five5 years previously. The macrobenthic community does not appear to have subsequently recovered. We also observed an absence of habitat-forming macroalgae in our study area, although similar investigation results revealed that they still prevail on an uninhabited island in Dongtou. The increasing disturbance caused by construction work may explain the decline in brown algae, which are mainly distributed in the low tidal zone. [ABSTRACT FROM AUTHOR]

The concentrations of eight heavy metals (As, Cd, Cr, Cu, Mn, Ni, Pb and Zn) were measured in the sediment, the isolated microplastics from the sediment and the body wall of sea cucumbers from farms in China. Accordingly, the heavy metal concentrations in the sediment were below the class I upper limit of Chinese sediment quality guidelines. Among heavy metals, the median concentrations of Cd and As were higher in the body wall than in the corresponding sediment. Additionally, the median concentrations of Cd, Pb, and Zn were higher on the microplastics than in the corresponding sediment. Furthermore, there was no significant correlation among heavy metals in sediment, sea cucumber and microplastics. This study contributes to the understanding of the heavy metal accumulation in the sediment, the microplastics and the body wall of the sea cucumber. Unlabelled Image • Microplastics may serve as a vector of heavy metals in the sea cucumber farms. • Sea cucumber may have a strategy accumulating some heavy metals in the body wall. • Sea cucumber A. japonicus might be considered as a bio-monitor for Cd. [ABSTRACT FROM AUTHOR]

Abstract The body wall of the sea cucumber is an important tissue with high nutritional value. In this study, the parents of Apostichopus japonicus were derived from Russia (R) and China (C). We examined the transcriptional profiles in the body wall from F1 hybrids (CR and RC) and purebreds (CC and RR) at 9 months. In total, 34.07 G clean data were obtained from the transcriptome, 100,870 unigenes were identified, and 26,483 unigenes were annotated. Based on edgeR, 1097–4,587differentially expressed genes (DEGs) were identified. In total, 50.72 M clean data were obtained from the small RNA libraries, and 202 miRNAs were identified, including 7 known miRNAs and 195 novel miRNAs. In total, 175 miRNAs were identified as significantly differentially expressed miRNAs (diffmRNAs). Additionally, 3538 target genes were predicted, and 2243 genes were annotated in NR, COG, GO and KEGG. Furthermore, the relationships between the small RNAs and transcripts were identified, and the novel miRNA functions were predicted by integrating the small RNAs and transcriptome. According to the saponins content, RR was lower than other lines. DEGs involved in the biosynthesis of saponins were identified, including 23 DEGs involved in glycosyl, 21 DEGs involved in P450s, 5 DEGs involved in transferases and 15 DEGs involved in OSCs, from these, gdp-l-fucose , fucTcpa2 and cyp17A 1 may affect the differences in the saponins development of the body wall in RR purebreds. In addition, miRNA_11347 and miRNA_32095 was associated in saponins. Our study provides fundamental information regarding the molecular mechanism of the heterosis of the sea cucumber and may suggest strategies for the selection of rapidly growing and highly nutritive strains of sea cucumber in aquaculture. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Tong’an Bay (TAB) is a semienclosed embayment in the north of Xiamen Island. The sea area of TAB was mainly used for aquaculture in enclosed areas before 2003. Since 2003, the districts surrounding TAB have been undergoing a rapid urbanization process, and the scale of land used for urban construction in these districts has been continuously increasing. Under the backdrop of rapid urbanization, the coastline of TAB has largely been transformed into an artificial coastline. Due to the large scale of land reclamation and, dredging activities and the opening of the Gaoqi-Jimei (GJ) Seawall, there have been relatively significant changes in the coastal and submarine geomorphology in central northern, western, and southern TAB and Wuyuan Bay as well as a significant increase in the area where artificial submarine geomorphologies are distributed; the number of surface sediment types in the TAB has increased, and sediments in the sea area surrounding engineering projects have been coarsening; the sediment transport pattern has not significantly changed at the mouth of TAB and in central northern TAB, but the suspended sediment transport direction near the GJ Seawall has changed to a certain extent. [ABSTRACT FROM AUTHOR]

Seawalls play an important role in protecting coastal regions by resisting storm surge and waves. However, a seawall can cause seabed erosion at its foot by facilitating hydrodynamic scouring, but the effects of seabed scour on wave loads have not been sufficiently considered. This paper presents a case study of increased wave load on the Gudong seawall in the Huanghe delta, China, which has experienced serious erosion since its construction. Four commonly-used empirical formulas, which were also verified through our physical simulation experiments, were used to calculate the wave loads on the crown wall of the seawall based on observed wave conditions. The maximum allowable wave load on the seawall was also determined based on historical extreme sea conditions that caused severe damage to the seawall. Our calculations showed that, the wave load has increased at least two times since the seawall's construction due to seabed scour, and the present crown wall cannot resist large waves with a 5-year return period, much less than the 50-year return period it was designed to resist. This suggested that the reasonable design of seawalls needs to adequately consider seabed scour as well as the associated increase in of wave loads. • The seabed in front of the Gudong seawall experienced serious erosion since its construction. • The wave force on the seawall increased greatly due to seabed scouring in front of the seawall. • The seawall is now unable to withstand extreme waves with return period of 5-years. • It is necessary to consider increased wave load induced by deepening water depth in seawall design. [ABSTRACT FROM AUTHOR]

The ancient seawall along the bank of Hangzhou Bay, which plays an important role in minimizing hazards to people and property along the coastline, has existed for hundreds of years. A recent field survey reveals that there are many hidden problems in the remaining ancient heritage. This work focuses on two points: the failure mechanism of the seawall structure and the ancient mortar prescription for conservation of the seawall, which are investigated through specially designed experiments. The conclusions obtained in this work are of important value for future maintenance of the seawall. [ABSTRACT FROM AUTHOR]

The article reports on developments concerning Japan's bilateral relations with China. The Japan-China Joint Study of History project's final report was released at the end of January 2010. Both countries expressed satisfaction with the project. There are no signs of progress in the efforts to reach an implementing agreement on joint development in the East China Sea. China protested Japan's decision to appropriate funds to support the construction of sea walls on Okinotorishima and Minamitorishma.

Local government built the monitoring project to know seawall performance and ensure its safety in Shanghai Pudong New Area. Up to now, monitoring data of some important monitoring items including tidewater level, seepage pressure, rainfall, wave, deformation, etc., have been collected. The monitoring system is introduced here. Furthermore, the data analysis methods have been studied particularly because the seawall works in a complex special environment. The rules and relationship within seepage pressure, tidewater, and rainfall are presented, and the time distance between tidewater and seepage pressure curves are confirmed by statistical distance analysis. To do quantificational analysis of seawall performance, two methods based on statistical theory and general regression neural network are used to establish monitoring models considering the main effect factors. Instances show the models can achieve good fitting and forecasting results of seawall seepage pressure. Application experiences are also presented. [ABSTRACT FROM AUTHOR]

Chinese coastal topography has changed significantly over the last two decades due to human actions such as the development of extensive land reclamation projects. Newly-reclaimed lands typically have low elevations (<10 m) and often experience severe ground subsidence. These conditions, combined with the more frequent occurrence of extreme sea-level events amplified by global climate change, lead to an increased risk of flooding of coastal regions. This work focuses on twelve Chinese coastal areas that underwent significant changes from 2000 to 2015 in their environments, correlated to relevant land reclamation projects. First, the ground changes between 2000 and 2015 were roughly computed by comparing the TanDEM-X and the Shuttle Radar Topography Mission (SRTM) digital elevation models of the investigated areas. These results indicate that six of the analyzed coastal zones have reclaimed more than 200 km2 of new lands from 2000 to 2015, with five of them in northern China. Second, we focused specifically on the city of Shanghai, and characterized the risk of flood in this area. To this purpose, two independent sets of synthetic aperture radar (SAR) data collected at the X- and C-band through the COSMO-SkyMed (CSK) and the European Copernicus Sentinel-1 (S-1) sensors were exploited. We assumed that the still extreme seawater depth is chi-square distributed, and estimated the probability of waves overtopping the coast. We also evaluated the impact on the territory of potential extreme flood events by counting the number of very-coherent objects (at most anthropic, such as buildings and public infrastructures) that could be seriously affected by a flood. To forecast possible inundation patterns, we used the LISFLOOD-FP hydrodynamic model. Assuming that an extreme event destroyed a given sector of the coastline, we finally computed the extent of the flooded areas and quantified its impact in terms of coherent structures potentially damaged by the inundation. Experimental results showed that two coastline segments located in the southern districts of Shanghai, where the seawalls height is lower, had the highest probability of wave overtopping and the most significant density of coherent objects potentially subjected to severe flood impacts. [ABSTRACT FROM AUTHOR]

The article describes the alternative design for the construction of the sea defence wall for Peng Chau Town in Hong Kong that allowed the wall to be constructed with the minimum of marine mud dredging. The most promising solution was to remove the need for the temporary sheeting and to ensure stability during dredging by reducing the dredged depth and flattening the dredged slope to provide an adequate factor of safety to support the existing seawall. The design was instigated to avoid the risks of dredging adjacent to the old town seawall due to concerns of damage to or even collapse of adjacent houses.

Flood management is a complex issue in Chinese cities that exhibit high populations and have undergone rapid urbanization. Urban flood management (UFM) approaches can be used to mitigate urban flood risk. To address urban issues of poor water quality and urban surface flooding, the Sponge City Program (SCP) was initiated in 2013 in China. The SCP aims to provide an opportunity for Chinese cities to improve their current UFM practices. This study looks at Guiyang (a pilot sponge city located in SW China) as a case study to identify the challenges and opportunities of UFM in China. Guiyang is a valley city surrounded by a hilly landscape. Using interview records and flood data, we illustrate that the primary type of flood in Guiyang is fluvial rather than surface water flooding. In Guiyang, the current function and targets of the SCP have yet to engage with the catchment level flood management, instead mainly focusing on the site-specific context (i.e., community level). Catchment flood management planning (CFMP) and natural flood management (NFM) both address this problem and may be a more suitable approach to manage flood discharge from the upper and middle catchments in Guiyang. In addition, it is suggested that a mixed option combining "hard" infrastructure (e.g., reservoirs and floodwalls) with "soft" flood management measures (e.g., improving people awareness and participation) may improve urban flood resilience in Chinese cities. [ABSTRACT FROM AUTHOR]

The article presents research on the effects to the Chinese ecosystem of the construction of seawalls along Chinese coastal wetlands and offers evidence suggesting that their construction will threaten biodiversity and ecosystem services. Topics include the importance of coastal wetlands in China, causes for the loss of the wetlands including government policy and economic growth, and policy recommendations for maintaining minimum coastal wetlands areas.

In the past several years, China has successfully constructed and enlarged several lands on the top of some coral reefs in the South China Sea (SCS thereafter) by the way of reclamation. A great number of revetment breakwaters have been built at the margins of these reclaimed coral reef islands, to defend these artificial lands from scouring and intensive wave impact. In order to quantitatively explore the dynamics characteristics, as well as the stability of these revetment breakwaters and their foundation under extreme wave impact, in this study, five large-scale wave flume physical model tests are conducted adopting a geometric similarity ratio of 1:10, to experimentally investigate the wave impact, displacement of the revetment breakwater, wave overtopping and the pore pressure in the dense calcareous sand foundation under the attack of random waves. Finally, the overall stability of the revetment breakwater is evaluated. The experimental results indicate that the maximum impact on the revetment breakwater applied by the fortified extreme waves reaches up to 6 kPa, the responding pore pressure in the dense coral sand foundation is not very significant, and the maximum volume of wave overtopping can be up to 0.39 m3/h per meter when there is no accropode installed to dissipate wave energy. There is no obvious deformation occurring in the dense foundation, and the displacement of the revetment breakwater is also not significant after long-term wave impacting. Combining all these experimental results, it is concluded that the revetment breakwater can stay stable under the condition of the fortified extreme ocean wave. However, the amount of wave overtopping is considerable, which would result in the delay of the process of the groundwater desalination in these reclaimed islands in the SCS. The test results further indicate that the usage of accropodes can considerably reduce the wave impact and the amount of wave overtopping. • The dynamics and stability of a revetment breakwater impacted by random waves is studied experimentally. • The revetment breakwater is built on reclaimed dense coral sand foundation in the South China Sea. • Five physical model tests are performed in a wave flume in which random waves are generated based on JONSWAP spectrum. • Wave impact and overtopping, dynamics of breakwater, pore pressure accumulation in foundation are all measured and analyzed. [ABSTRACT FROM AUTHOR]

Water engineering, also known as hydraulic engineering, mainly includes dams, reservoir embankments, water defense structures, seawalls, water channels and resettlement zones, etc. The huge projects, like the Three Gorges Dam in China, are well managed and under full safety monitoring. However, there are still a large number of small and medium-sized hydraulic structures which lack necessary safety monitoring. For instance, the amount of reservoirs in China is 98,000, most of which have serviced for over 50 years, and about 1/3 of the reservoirs were in risk at the beginning of the 21st century. What's more, more than 14,500 km of seawalls suffers erosion and almost 3,000 km of water channels cross seismic fault and mining goaf. Satellite-based InSAR provides us with an innovative way to monitor the hydraulic structures with a large area and low cost. Sentinel-1 working at C-band with a coverage of 250 km could offer a quick glance over a large area. More details of small deformation are detected by high-resolution TerraSAR-X or COSMO-SkyMed data, as well as L-band ALOS-2 provides more information for the large deformation and fast decorrelation areas. In this manuscript, we will take the Yellow River Delta, Shandong Province, China, which suffers land subsidence due to groundwater and brine extraction, as the study area. The deformation process of several reservoir embankments (i.e., Shuangwangcheng reservoir, Guangnan reservoir, Yeyuan reservoir), as well as the seawalls of Laizhou Bay, will be revealed by multi-band InSAR with different spatial resolutions. We will also evaluate the performance of different DEM products (i.e., TanDEM and SRTM1) in the terrain phase removal of the InSAR data processing. The application will prove the feasibility of InSAR for the general survey of water structures and for decision support and engineering risk mitigation. [ABSTRACT FROM AUTHOR]

Zheng, J.-H., Jeng, D.-S. and Mase, H., 2007. Sandy beach profile response to sloping seawalls: an experimental study. Journal of Coastal Research, SI 50 (Proceedings of the 9th International Coastal Symposium), 334 – 337. Gold Coast, Australia, ISSN 0749.0208. Seawalls are commonly used as a tool for coastal defence worldwide. Most previous studies have considered the case of vertical seawalls and descriptions of existing seawalls, rather than the influence of different designs of sloping seawalls on beach erosion. In this study, laboratory investigations of an undistorted moveable bed model were conducted to determine the resulting beach profile of artificial sandy beaches. In the experiments, three different sloping seawalls were considered under erosive wave conditions with a 50-year return period. The coast of Northern Jiangsu Province, China, is used as a case study. To simulate natural conditions, similarity criteria are developed assuming that the energy dissipation per unit volume along the beach profile is uniform and that the wave properties can be properly scaled by Froude criteria. Field surveys of beach profile changes due to the storm surge induced by Typhoon 9711 were taken to validate the experimental model and good agreements were attained. Spatial profile configurations were studied by examining dominant profile features such as the break point bar and the scour trough on the seawall-backed profiles. Experimental results provided a reference for the maintenance of artificial sandy beaches and the design of seawalls on the coast of Northern Jiangsu Province, China. [ABSTRACT FROM AUTHOR]