Showing papers in "Journal of Coastal Research in 2007"
TL;DR: In this paper, the authors compared the predictive accuracy of various calculated erosion rates, including end point rate (EPR), average of rates (AOR), minimum description length (MDL), jackknifing (JK), OLS, reweighted least squares (RLS), WLS, RWLS, and weighted least absolute deviation (WLAD).
Abstract: Beach erosion has direct consequences for Hawaii's tourist-based economy, which depends on the attraction of beautiful sandy beaches. Within the last century, however, beaches on Oahu and Maui have been narrowed or completely lost, threatening tourism and construction development. In order for the counties and state of Hawaii to implement coastal regulations to prevent infrastructure damage, it is necessary to find a statistically valid methodology that accurately delineates annual erosion hazard rates specific to Hawaii. We compare the following erosion rate methods: end point rate (EPR), average of rates (AOR), minimum description length (MDL), jackknifing (JK), ordinary least squares (OLS), reweighted least squares (RLS), weighted least squares (WLS), reweighted weighted least squares (RWLS), least absolute deviation (LAD), and weighted least absolute deviation (WLAD). To evaluate these statistical methods, this study determines the predictive accuracy of various calculated erosion rates, incl...
209 citations
TL;DR: In this paper, the authors provided the first assessment of the type and quantity of marine litter at Armacao dos Buzios, Brazil, and quantified an overall mean litter density of 13.76 items /100 m2.
Abstract: Anthropogenic debris constitutes a significant threat to the marine environment, representing a hazard not only for marine and terrestrial animals but also for human activities, health, and tourism. This study provided the first assessment of the type and quantity of marine litter at Armacao dos Buzios, Brazil. Buzios is a popular tourist resort, which attracts visitors because of its proximity to Rio de Janeiro City. Sampling was conducted in belt transects of 4-m width, parallel to the coastline. To evaluate the composition and abundance of beach litter, all visible pieces of man-made debris (the number of items) found on each belt transect were identified in situ and recorded. Nearly 16,000 items of litter, belonging to seven categories were counted. An overall mean litter density of 13.76 items /100 m2 was quantified on the Armacao dos Buzios beaches. Paper was the most abundant litter item, in particular, represented by cigarette butts. Much of the litter items are discarded by visitors to t...
143 citations
TL;DR: In this paper, a zonazione vegetazionale viene analizzata mediante transetti eseguiti nei siti meglio conservati della costa del Lazio (Italia centrale), allo scopo di verificare la relazione tra le comunita and le pendenze/esposizioni per esse misurate.
Abstract: RIASSUNTO La ricerca riguarda alcuni ecosistemi sabbiosi delle coste del Mediterraneo per i quali e stata analizzata la zonazione vegetazionale in relazione alla morfologia delle dune, attraverso l'applicazione di un test di randomizzazione. Si postula che la pendenza e l'esposizione rappresentino le variabili essenziali per analizzare la posizione delle comunita vegetali lungo il gradiente ecologico che si sviluppa, in questi ecosistemi, dal mare verso l'entroterra. La zonazione vegetazionale viene analizzata mediante transetti eseguiti nei siti meglio conservati della costa del Lazio (Italia centrale). Su tali dati viene eseguita l'analisi della varianza, mediante test di randomizzazione, allo scopo di verificare la relazione tra le comunita e le pendenze/esposizioni per esse misurate. I risultati dei transetti di vegetazione mostrano che nell'area di studio non e mai rappresentata la sequenza fitocenotica ideale completa. Alcune comunita sono piuttosto comuni e diffuse, mentre altre sono rare e present...
114 citations
TL;DR: In this article, the authors used digital images of the intertidal region to map shorelines and the inter-tidal bathymetry along four geo-morphically and hydrodynamically distinct coastlines in the United States, United Kingdom, The Netherlands and Australia.
Abstract: Digital images of the intertidal region were used to map shorelines and the intertidal bathymetry along four geo-morphically and hydrodynamically distinct coastlines in the United States, United Kingdom, The Netherlands, and Australia. Mapping methods, each of which was originally designed to perform well at only one of the four sites, were applied to all four sites, and the results were compared to direct topographic surveys. It was determined that the rms errors of image-derived versus directly surveyed elevations depended on the prevailing hydrodynamic conditions as well as differences in each of the four different mapping methods. Before these differences were accounted for, rms errors ranged from 0.3 to 0.7 m. An empirical correction model that computed local estimates of setup, swash, and surf beat amplitudes reduced errors by about 50%, with residual rms errors ranging between 0.1 and 0.4 m. The model required tuning only one parameter that determined how each method was affected by swash ...
114 citations
TL;DR: Waves were measured over tidal cycles on a sloping, basaltic shore platform at Scots Bay in the macrotidal Bay of Fundy (large tidal range 13.5 m) and on a horizontal, argillite platform at Mont Louis in Gaspe, Quebec (Large tidal range 3 m), and video cameras were used to record the height and period of the waves against a series of graduated metal poles anchored along surveyed, shore normal profiles as discussed by the authors.
Abstract: Waves were measured over tidal cycles on a sloping, basaltic shore platform at Scots Bay in the macrotidal Bay of Fundy (large tidal range 13.5 m), and on a horizontal, argillite platform at Mont Louis in Gaspe, Quebec (large tidal range 3 m). Video cameras were used to record the height and period of the waves against a series of graduated metal poles anchored along surveyed, shore-normal profiles. Field measurement and theoretical considerations suggest that wave height increases with elevation at Scots Bay, reflecting the occurrence of a gently sloping tidal flat below the midtidal level and higher gradients on the upper than on the lower parts of the platform. Calculated pressures generated within the rock along joints and other discontinuities suggest that wave conditions are suitable for mechanical-wave erosion at Scots Bay. Waves generally break on the low tide cliff at the seaward edge of the platform at Mont Louis, preventing any wave action on the shallow, flooded platform surface behin...
110 citations
TL;DR: In this article, the authors presented the coastal vulnerability index (CVI) for the estimation of vulnerability of the coastal region of Mangalore coast, India, from Talapady to Surathkal.
Abstract: The paper presents the coastal vulnerability index (CVI) for the estimation of vulnerability of the coastal region of Mangalore coast, India, from Talapady to Surathkal. The CVI is an indication of the relative vulnerability of the various segments of the Mangalore coast to coastal erosion hazards. The following variables are used in the estimation of CVI, which is used to rank the vulnerability of the coastal regions: geomorphology, regional coastal slope, shoreline change rates, and population. The rankings for each variable were combined and an index value calculated for 1′ × 1′ grid cells covering the study area.
105 citations
TL;DR: In this article, a segmentation-based image processing method was proposed to automate the extraction of tidal datum referenced shorelines from airborne light detection and ranging (LIDAR) data.
Abstract: This research presents a segmentation-based, image processing method to automate the extraction of tidal datum referenced shorelines from airborne light detection and ranging (LIDAR) data. The method first segments a LIDAR digital elevation model (DEM) into a binary image, consisting of land and water pixels, by intersecting the LIDAR DEM and the tidal datum surface. A chain of image processing algorithms, including region grouping and labeling, two passes of image region scanning, a mathematical morphology operation, line tracing, and vectorization, is sequentially applied to the segmented binary image. Our applications to the upper Texas gulf coast show that the method is efficient, accurate, objective, and replicable. Spatially detailed shorelines can be derived from the LIDAR data with minimal human intervention. The method is a substantial technical improvement over standard cross-shore profile and contouring methods. We also examine and quantify the effects of vertical measurement error of ...
101 citations
TL;DR: In this paper, the authors identify and quantify those stretches in the Buenos Aires province that present different degrees of risk in view of the rise of the mean sea level and to determine its nature.
Abstract: The purpose of this work is to identify and quantify those stretches in the Buenos Aires province that present different degrees of risk in view of the rise of the mean sea level and to determine its nature. The study focused on the Buenos Aires province coast because its variant geomorphology represents the different morphologies along the whole of the Argentinean coastline. The aim of this article is to study the response of two of the coastal vulnerability equations to the environmental diversity and to determine which one is more suitable to be applied to the rest of the country. On verifying the equations, CVI6 was found to be more appropriate for the analysis of coasts with different morphologies. Depending on the physical characteristics of each area, the consequences would include flooding and the loss of low lands in areas such as the Samborombon Bay, Bahia Blanca Estuary, and Anegada Bay, and the eroding of the beaches between Punta Rasa and Bahia Blanca.
101 citations
TL;DR: In this article, the amount and types of beach litter deposition at a selection of beaches in the Firth of Forth, Scotland, was studied between July 2001 and December 2003, with the most common litter type recorded being plastic.
Abstract: Beach litter deposition at a selection of beaches in the Firth of Forth, Scotland, was studied between July 2001 and December 2003. The amount and types of beach litter is relatively consistent among beaches and over time, with an increased abundance of certain litter types at irregular intervals. Plastic is the most common litter type recorded. The amount of litter items per square metre is affected by Local Authority beach cleaning, community beach cleanings, and the presence of sewerage structures and takeaway facilities. Litter from fishing and shipping was relatively low compared with litter from recreation and sewage-related debris. It is likely that climatic conditions and tidal patterns are the greatest influence on the abundance of beach litter. Management actions are required to effect a reduction in beach litter. A combination of education, provision of adequate waste reception facilities, and enforcement of legislation is needed to tackle beach litter.
99 citations
TL;DR: In this article, a vergleichende Einstellung zu managed realignment in England and Deutschland is presented, with a focus on the negativen Auswirkungen des beschleunigten Meeresspiegelanstiegs auf the ohnehin gefahrdeten tidebeeinflusten Lebensraume zuruckzufuhren.
Abstract: ZUSAMMENFASSUNG Die Kustenmanagementmasnahme ‘managed realignment’ (in deutsch oft ‘Deichruckverlegung’, ‘Deichoffnung’ oder ‘Ausdeichung’ genannt) wurde im Laufe des letzten Jahrzehnts zunehmend diskutiert. Dies ist unter anderem auf die potentiell negativen Auswirkungen des beschleunigten Meeresspiegelanstiegs auf die ohnehin gefahrdeten tidebeeinflusten Lebensraume zuruckzufuhren. Eine vergleichende Studie der Einstellung zu managed realignment in England und Deutschland hatte zum Ziel, sowohl Gemeinsamkeiten und Unterschiede festzustellen, als auch die zukunftige Nutzung dieser Kustenmanagementmasnahme einzuschatzen. Wahrend die Erwagung von managed realignment generell als eine positive Entwicklung empfunden wird, wurden bedeutende und manchmal uberraschende Unterschiede in der Anwendung gefunden—abhangig von verschiedenen Faktoren wie z.B. Naturlandschaft, Zustand der Kustenschutzanlagen, und politische- und kulturebedingte Einstellung. Die bestehenden managed realignment Flachen befinden sich haupt...
97 citations
TL;DR: In this article, the authors analyzed seasonal changes in the frontal zone position and suggest an enhaced migration during El Nino Southern Oscillation (ENSO) warm and cold episodes, reaching higher latitudes during the former (e.g., autumn of 1998).
Abstract: Seasonal (autumn and spring) and multiannual (1991, 1995, 1996, 1997, 1998, and 2001) variability in the composition of water masses on the Uruguayan shelf were analyzed. The main difference between seasons was the presence of Tropical Water (TW) and a relative dominance of Subtropical Water (STW) over Subantartic Water (SAW) in autumn, whereas spring was characterized by a dominance of SAW and the absence of TW. Changes in the composition of water masses, surface temperature distributions, and front positions and strengths are discussed in regards to biological implications. Our results reveal seasonal changes in the frontal zone position and suggest an enhaced migration during El Nino Southern Oscillation (ENSO) warm and cold episodes, reaching higher latitudes during the former (e.g., autumn of 1998). During cold episodes, the position of the frontal zone reached lower latitudes, with prevailing cold waters over the shelf. Higher frontal strength was observed during ENSO episodes, mainly becau...
TL;DR: In this paper, the authors used a simple analytical model of reservoir compaction and a numerical model to investigate surface subsidence in the area of the Lapeyrouse Field in southern Louisiana.
Abstract: We use a simple analytical model of reservoir compaction and a numerical model incorporating both reservoir compaction and fault slip to investigate surface subsidence in the area of the Lapeyrouse Field in southern Louisiana. A releveling survey shows approximately 20 m of elevation change over a 30 years time period that includes the period of extensive oil and gas production from a number of reservoirs at depth. The degree and extent of subsidence estimated from a simple analytical model of compaction predicts approximately half of the elevation change measured from the releveling surveys. Incorporating the impact of compaction-induced slip along the Golden Meadow Fault, located at the northern edge of the Lapeyrouse Field, on surface subsidence still does not account for all of the measured subsidence. Coastal wetland loss is a result of complicated process and it is difficult to isolate the impact of specific mechanisms. This study suggests that land subsidence induced by hydrocarbon product...
TL;DR: In this paper, the authors focused mainly on the coastline movements at the northeast coasts of the Aegean Sea in Turkey and used satellite data from Landsat MSS, TM, and ETM collected between 1975 and 2001.
Abstract: This paper focuses mainly on the coastline movements at the northeast coasts of the Aegean Sea in Turkey. The Aegean Sea is a semiclosed sea that has unique geographical features and covers an area of 191,000 km2. The study area includes the coastal zone located between the southeastern part of the Meric River mouth and the Dalyan Lake coasts. The Meric Delta has accreted toward the Aegean Sea as a result of sediment discharge and transport. In contrast to this, the width of the natural land barrier between the Aegean Sea and the Dalyan Lake has decreased over the years because of coastal erosion. These processes have caused the morphological changes of coastline along some parts of the northeast coasts of the Aegean Sea. In this study, these changes were examined by using satellite data from Landsat MSS, TM, and ETM collected between 1975 and 2001. In the image processing step, registration, ISODATA classification, and temporal image ratioing techniques were used to carry out coastline change as...
TL;DR: It is confirmed that human disturbance is more frequent than natural disturbances, and that humans decrease nest attendance substantially and more than any other source of disturbance.
Abstract: Hooded Plovers (Thinornis rubricollis) and recreationists co-occur on the ocean beaches of southern Australia, and it has been suggested that disturbance of the breeding birds by humans constitutes a conservation problem. This study examines whether humans disturb incubating Hooded Plovers and places that disturbance in context with naturally occurring disturbances. Incubating Hooded Plovers encountered and responded to a variety of human and natural stimuli. The most common response involved leaving the nest for a period of time (an “absence”), and humans were responsible for 33.1% of time spent off nests. The response rates of incubating birds varied with the type of stimulus, with higher than expected response rates to two species of potentially predatory birds. About 17% of encounters with potential causes of disturbance occurred while birds were already responding to other disturbance, and this prolonged the return to the nest. Absences from the nest that were not apparently caused by distur...
TL;DR: In this article, the authors summarize several studies that find a high correlation between shoreline change and subaerial volume change and conclude that the average correlation coefficient is 0.88.
Abstract: It is difficult and expensive to calculate changes in sediment volume for large sections of sandy beaches. Shoreline change could be a useful proxy for volume change because it can be collected quickly and relatively easily over long distances. In this paper, we summarize several studies that find a high correlation between shoreline change and subaerial volume change. We also examine three new data sets. On Cape Cod, Massachusetts, the correlation coefficients between the time series of shoreline change and subaerial volume change at two locations are 0.73 and 0.96. On Assateague Island, the correlation coefficient between along-coast variations in shoreline change and subaerial volume change is 0.71. On the Outer Banks of North Carolina, the average correlation coefficient between temporal variations in shoreline change and subaerial volume change is 0.84. For spatial variations, the average correlation coefficient is 0.88. It is therefore concluded that shoreline change is a useful proxy for s...
TL;DR: In this paper, documented examples are chosen to address how human-induced changes have made profound impacts on the coastal erosion in Taiwan, and solutions to the erosion problem for the benefit of others in different parts of the world.
Abstract: Coastal erosion is an islandwide problem in Taiwan. On the basis of the result of the most recent survey, more than 80% of the island's sandy coasts have undergone erosion over the past 3 decades. Naturally and historically with the specific tectonic environment and uplifting rate in Taiwan, sufficient sediments had been yielded and transported to the coastal area, resulting in an advancing shoreline along the trailing edge coast during the last several centuries. However, human interventions have contributed significantly to the erosion in more recent times. In this paper, documented examples are chosen to address how human-induced changes have made profound impacts on the coastal erosion in Taiwan. The information presented will provide a better understanding of the coastal processes, and solutions to the erosion problem for the benefit of others in different parts of the world.
TL;DR: In this article, the authors examine a series of challenges to spatial modeling that have emerged from the development of a national to global impact tool, DIVA (Dynamic Interactive Vulnerability Assessment), addressing how best to utilize the limited data to develop a reference framework for modeling vulnerability within the global coastal environment.
Abstract: A coherent approach to structuring reference units for coastal vulnerability analysis is often required for large-scale analyses of the coastal system. However, a review of existing spatial reference frameworks within vulnerability analyses demonstrates that our use of coastal space within large-scale models remains relatively poor. This paper examines a series of challenges to spatial modeling that have emerged from the development of a national to global impact tool, DIVA (Dynamic Interactive Vulnerability Assessment). The paper addresses how best to utilize the limited data to develop a reference framework for modeling vulnerability within the global coastal environment. It outlines the approach to spatial modeling that has been developed for use within the DIVA tool: segmenting the coastal zone into a series of relatively homogenous reference units at the scale of DIVA, based on the behavior of the physical, social, and economic systems within the zone. The importance of effective spatially defined models is emphasized within the paper. Encouraging greater spatial recognition and definition of the behavioral environment of the coast is critical to modeling space within the coastal system. By decreasing spatial uncertainties in the creation of reference units for vulnerability analysis, the accuracy of modeling within large-scale coastal environments can be further improved.
TL;DR: Habitat choice and interactions of foraging shorebirds and gulls were studied at a migratory stopover in Delaware Bay, New Jersey, to suggest that there may be some competition for foraging space among foraging species, especially between the shorebird and the larger gulls, that human disturbance affects shore-birds more strongly than gulls
Abstract: Habitat choice and interactions of foraging shorebirds and gulls were studied at a migratory stopover in Delaware Bay, New Jersey. Foraging, vigilance, aggressive behavior, and habitat choice of shorebirds were affected by the presence of gulls. There were significant differences in the time each species devoted to actively feeding; knots spent significantly less time foraging than did the other species. Birds congregated in the habitats where their foraging rates were the highest. When turnstones and laughing gulls fed in larger conspecific flocks, they had higher foraging times. Red knots were most aggressive toward laughing gulls, turnstones were most aggressive toward herring gulls, sanderlings were most aggressive toward turnstones, and semipalmated sandpipers were most aggressive toward knots. There were significant differences in habitat use: 1) Gulls and turnstones were more abundant along the tide line, 2) turnstones were more abundant on the upper beach, 3) semipalmated sandpipers and t...
TL;DR: In this paper, a methodology for monitoring long-term beach face volume change with a combination of intermittent profiling and video imagery is developed, which can be mapped from video with the use of movement of the waterline over a tidal cycle.
Abstract: A methodology for monitoring long-term beach face volume change with a combination of intermittent profiling and video imagery is developed. Intertidal beach morphology can be mapped from video with the use of movement of the waterline over a tidal cycle. Such maps provide detailed information on spatial and temporal evolution of the intertidal area, but no direct information on beach face volume changes as a whole. However, beach face volume might well be correlated with cross-shore changes to a contour located in the intertidal zone. This is significant because such a parameter can be calculated from maps of the intertidal morphology generated with video images. This idea was tested with a series of video images and surveys that were collected over a year and a half on an intermediate beach on the Coromandel Peninsula, New Zealand, over a wide range of conditions. The surveyed profiles show a strong (r2 = 0.95) relationship between the surveyed cross-shore location of the 2-m contour and the su...
TL;DR: In this article, the authors applied optically stimulated luminescence (OSL) to the dating of recent aeolian sand ridges on Romo, an island off the southwest coast of Denmark.
Abstract: The application of optically stimulated luminescence (OSL) to the dating of recent aeolian sand ridges on Romo, an island off the southwest coast of Denmark, is tested. These sand ridges began to form approximately 300 years ago, and estimates of the ages are available from historical records. Samples for OSL dating were taken ∼0.5 m below the crests of four different dune ridges; at least five samples were recovered from each ridge to test the internal consistency of the ages. Additional samples were recovered from the low lying areas in the swales and from the scattered dune formations in a broad hummocky area landward of the well-defined ridges. Despite low luminescence signals, we were able to obtain a mean age for the youngest ridge of 17 ± 2 years, consistent with the known age of >28 years. Optical ages of individual samples in our study ranged between 10 ± 3 years and 690 ± 50 years, and all ages were broadly consistent with those expected from historical information. The oldest aeolian s...
TL;DR: In this paper, the effects of vegetation, in particular beach grass, on blown sand in terms of elevation changes of a mobile sand bed and distributions of mean wind velocity for various vegetation canopies were investigated.
Abstract: Wind-tunnel experiments were conducted to investigate the effects of vegetation, in particular beach grass, on blown sand in terms of elevation changes of a mobile sand bed and distributions of mean wind velocity for various vegetation canopies. For flexible vegetation layer displacement amplitude of vegetation leaf sway was also measured. The results indicate that a vegetation canopy with low height, high density, and vegetation flexibility is effective in reducing the sand-transport rate. Within and above a canopy of flexible vegetation, the vibrations of leaves increases the air turbulence, which creates a complex interaction between the mean wind velocity and the air turbulence, and thereby reduces the wind velocity in the vegetation area; consequently, the sand-transport rate decreases.
TL;DR: In this paper, a collection of deep water (>100 m) wave records was assessed to create a long-term, statistically reliable data set, and the probability distributions were used to quantify the potential for useful energy extraction from the coastal waves of California.
Abstract: In this article, a collection of deep water (>100 m) wave records was assessed to create a long-term, statistically reliable data set. These wave data were derived from buoy data of the Coastal Information Data Program (CDIP) at the University of California, San Diego (UCSD), Scripps Institute of Oceanography; the National Data Buoy Center (NDBC) at the National Oceanic and Atmospheric Administration (NOAA); and other sources. From this data set, long-term annual averages and monthly wave probability distributions were analyzed for 10 one-degree-latitude bins, bounded by the 100-m and 1000-m depth contours seaward of the California coast. The probability distributions were used to quantify the potential for useful energy extraction from the coastal waves of California. Optimal locations for developing wave energy installations are specified. South of Point Conception, California, the wave energy arriving from North Pacific storms is efficiently blocked by the significant change in the California ...
TL;DR: In this article, the morphodynamics of a swash bar was monitored over two tidal cycles during a storm event at Skallingen, Denmark, and the onshore migration of the swash bars occurred despite little change in the offshore wave height from one tidal cycle to the next and in conditions that are typically associated with offshore transport and bar migration.
Abstract: The morphodynamics of a swash bar was monitored over two tidal cycles during a storm event at Skallingen, Denmark. Higher water levels during the first tidal cycle forced waves to break either landward of, or at, the bar crest. The bar was unable to significantly alter the pattern of wave breaking over the foreshore slope, creating a potential for bar erosion through an offshore transport of sediment. In response, the bar became more symmetric in cross-section, and its height decreased. Lower water levels during the second tidal cycle forced waves to break on the seaward slope, causing the bar to rebuild and its crest to migrate onshore. The onshore migration of the swash bar occurred despite little change in the offshore wave height from one tidal cycle to the next and in conditions that are typically associated with offshore transport and bar migration. The results further illustrate a strong tidal dependency in which water depth relative to bar height is an important control on the morphodynam...
TL;DR: In this paper, the authors used erosional and depositional features to infer the main processes that acted during inundation from the tsunami, including ripples from inflow and outflow, graded bedding, parallel lamination, and double-layered deposits.
Abstract: The devastating December 26, 2004, tsunami produced abundant geologic effects along the Andaman coast of Thailand. The tsunami inundated the numerous sandy beaches and flowed over the adjacent aeolian dunes. On some of the dunes, the tsunami scoured circular holes 10–30 cm in diameter, and in its waning phases, it coated the holes with mud. The tsunami locally deposited a sand sheet that ranged from 0–30 cm in thickness, with an average thickness of approximately 10 cm. Sedimentary structures within the sand sheet include ripples from inflow and outflow, graded bedding, parallel lamination, and double-layered deposits. Erosion, locally severe, affected sand beaches and tidal inlets. We use these erosional and depositional features to infer the main processes that acted during inundation from the tsunami.
TL;DR: In this paper, surface sediments from Cadiz and Algeciras Bays (southern Spain) were analyzed by a sequential procedure for Cu, Zn, Cd, Pb, Fe, Ni, Cr, and Mn.
Abstract: Surface sediments from Cadiz and Algeciras Bays (southern Spain) were analysed by a sequential procedure for Cu, Zn, Cd, Pb, Fe, Ni, Cr, and Mn to determine their distribution among four geochemical phases (acid-soluble, reducible, oxidisable, and residual). The total metal content was also determined. The results showed that large amounts of metal accumulate in the interior of Cadiz Bay, whereas in Algeciras Bay, the highest levels of metal are found near the city of Algeciras and an area of major industrial activity. A comparison of metal levels with the sediment quality guidelines suggested by Long et al. (1995) showed areas in both bays in which pollution is sufficient to have noxious effects on marine organisms. Chemical partitioning of the metals revealed that Zn and Pb present the highest percentages in the reducible fraction and that Ni, Cr, and Cd are highest in the residual and reducible fractions. Cu shows the greatest proportion in the oxidisable fraction and Mn in the acid-soluble fr...
TL;DR: In this paper, a methodology for integrating state-of-the-art storm surge and wave prediction models as an effective tool for engineering design of coastal infrastructure and facilitation of hurricane emergency management is presented.
Abstract: A recent study reveals that more than 60,000 miles (>96,500 km) of coastal roadways are in the 100-year floodplain in the United States and vulnerable to the attacks of water surges and storm waves generated by hurricanes. Mitigating the effects of coastal flooding requires accurate predictions of the destructive hydrodynamic forces. This study demonstrates a methodology for integrating state-of-the-art storm surge and wave prediction models as an effective tool for engineering design of coastal infrastructure and facilitation of hurricane emergency management. The methodology has the capability of resolving complex geometry and topography typical of coastal road flooding. The surge model incorporates moving shoreline conditions associated with flooding and allows for nonlinear interactions among astronomical tide, storm surge, and wave setup. The wave model takes into account the unsteadiness of wind forcing, currents, and water levels. A historical hurricane event is simulated for the landfall ...
TL;DR: In this paper, 15 loblolly pines (Pinus taeda) were cored for dendroecological analysis to address the impact of rising sea level in a rapidly submerging Maryland estuarine forest.
Abstract: To address the impact of rising sea level in a rapidly submerging Maryland estuarine forest, 15 loblolly pines (Pinus taeda) were cored for dendroecological analysis. The study area is a pure stand of loblolly pine that extends down an elevation gradient into surrounding marsh where dead stumps and snags indicate a retreating forest margin. Although relative sea level has risen considerably and there are dead trees at the forest-marsh interface, there is no associated decline in ring width, making sea level–induced mortality unlikely. Instead, ring width is correlated positively with annual precipitation and winter temperature and negatively with summer temperatures. Although recruitment of new pines was continuous between 1910 and 1930, there has been no more active recruitment except for a small age class established immediately after regional drought. Because recruitment is failing in the present forest despite abundant seedlings and an open canopy, recruitment ability appears to be limited by...
TL;DR: In this article, the authors review and analyze the cyclic morphodynamics and sand-bypassing processes at the Ameland Inlet, The Netherlands, and develop an aggregate model to describe the inlet morphology at this intermediate timescale, which allows erosion and accretion of the shoal and bars to occur about their longterm equilibrium.
Abstract: In this paper, we review and analyze the cyclic morphodynamics and sand-bypassing processes at the Ameland Inlet, The Netherlands. The inlet is located between the islands of Terschelling and Ameland in the Dutch Wadden Sea. The bypassing rate and sand storage have a periodicity of 50 to 60 years in connection with the migration of the channels in the inlet and the transformation of the gorge between a one-channel and a two-channel system. These developments modulate the volumes of the shoal and bypassing bars and produce an attenuating sand wave toward the downdrift coast. An aggregate model is developed to describe the inlet morphology at this intermediate timescale. The model is based on a modified equilibrium-volume approach, which allows erosion and accretion of the shoal and bars to occur about their long-term equilibrium. The model results depict observed morphologic behaviors of the inlet and corroborate the measured modulation of the downdrift coastline. The simulation of the effect of t...
TL;DR: In this paper, the applicability of six existing formulas for computing the breaker depth index was examined with the use of a large amount of published laboratory data (524 cases collected from 22 sources).
Abstract: This study was undertaken to establish the most reliable breaker depth index formula that will yield satisfactory predictions for a wide range of hydraulic and beach conditions. The applicability of six existing formulas for computing the breaker depth index was examined with the use of a large amount of published laboratory data (524 cases collected from 22 sources). The behavior of these formulas was studied with respect to the main governing parameters, which are the beach slope and the deep-water wave steepness. It was found that most formulas show quite good predictions for cases including gentle slopes (0.01 0.1), and the formulas do not always present a physically correct behavior with respect to the two main parameters. A new formula is proposed to predict the breaker depth index with the best possible accuracy. Also, a discussion is included on the application of the formula to ra...