Despite acknowledgement by scientists and modelers of the shortcomings of mathematical models of beach behaviour, they continue in widespread use for engineering design and environmental impact studies. In part, this is because of the assumed absence of a viable alternative approach to prediction. The objective of this paper is to suggest that a conceptual approach can succeed as an alternative to mathematical models for predictions with accuracy ranges useful for engineering and coastal management purposes. The most valuable information for prediction is past engineering experience on the beach in question or the experience on neighboring beaches. The next most useful may be the global experience on oceanographically similar beaches. Another approach is the use of geoindicators and field studies on the beach. The widely applied “predict nothing” approach to beach engineering may well work if fortified by common sense. Finally, a composite approach in which the assembled body of information on a stretch of coast is considered and used to provide an expert judgement on the likely course of future coastal behavior is considered the best option. In all cases a gradualism or go-slow approach is strongly recommended because no method can accurately predict the response to engineering of the complex natural coastal system. Answers from such approaches will be approximations with significant error bars expressed in qualitative terms but will be based on a reality that applied models with all their simplified assumptions and omissions are incapable of achieving.

Studies on suspended matter in inverse estuaries are relatively scarce compared with similar studies in classic estuaries. The longitudinal circulation pattern in such estuaries is opposite to that observed in classic estuaries and may significantly affect the transport of suspended sediments. The Upper Gulf of California is a macrotidal inverse estuary having negligible river input but sustaining a high concentration of suspended matter, mainly derived from erosion of bed sediments. The amount of suspended particulate matter in the water column is controlled by tidal resuspension. On the western side of the Upper Gulf, horizontal fluxes of suspended particulate matter integrated between 1 m and 5 m above the bed were influenced by near-bed density-driven flow during neap tides. Maximum neap tide fluxes during ebb tide were − 21.5 g·m⁻¹·s⁻¹ to −24.9 g·m⁻¹·s⁻¹ while peak fluxes during flood tide were one order of magnitude smaller. The loss of suspended sediment to deeper water was controlled by gravity currents, which are typical of the near-bed circulation of inverse estuaries. Similar outflow from the Upper Gulf was not observed on the eastern side.

A salty wedge intrusion into the fresh river water is a relevant feature at the external zone of the Río de la Plata estuary. Accordingly, a particular sound velocity profile with a strong positive gradient very different from typical profiles at open sea areas, takes place. Upon these special conditions, using a Normal Mode Model the acoustic field is studied. The optimum frequency of propagation (f_op), i.e. the frequency in which there is a minimum in sound transmission losses (TL), is determined. The influence on f_op value of the seasonal changes in the sound velocity profile, the source and receiver positions and the change in the wind forces, is analysed. It is concluded that f_op values depend significantly on the source and receiver geometry. They have a distinct dependence on seasonal changes of the sound velocity profile and they remain invariant with increasing wind forces.

A numerical model is used to investigate coastal upwelling in the South Brazil Bight. The wind in the area is predominantly from the northeast, especially in summer, which is upwelling favorable. Reversals of the wind direction are frequent and intense during the winter, due to the passage of frontal systems. The offshore circulation is dominated by the Brazil Current, which flows southward meandering around the 200 m isobath. Significant shelf-break upwelling has being associated with Brazil Current cyclonic meanders. To assess the relative importance of the two processes in the pumping of South Atlantic Central Water (SACW) onto the continental shelf, three cases are analyzed: (1) wind-driven upwelling; (2) upwelling induced by Brazil Current meanders and (3) both effects acting together. The results show that in the coastal area upwelling/downwelling is mainly caused by the wind, whereas the cyclonic meanders of the Brazil Current are the dominant mechanism in the generation of vertical velocities over the shelf break and slope. This meander-induced upward motion brings the SACW to shallower depths, where it is influenced by the wind. In this situation, when both effects act together, the SACW penetrates all the way to the coast.

Cyclic morphology is related to water levels on a shallow spit-platform in the Danish Wadden Sea. Water levels were used as a dynamic parameter because low water levels, water levels at moderate wind set ups and high water levels occur at different wind situations and they result in different morphology. Low water levels result in a flat sand bar with one deep and narrow ebb channel. Water levels at moderate wind set ups result in several wide and shallow ebb channels. After a storm the spit-platform is flat and low with no dissecting ebb channels. Sand bars on the spit-platform migrate up to 35 m/month. A model proposing the different morphology at the three different water level stages is presented.

Several new concepts have challenged the traditional view of northern Gulf coast sea-level history in recent years. Claims for higher than present mid and late Holocene sea-levels implied substantial sea-level oscillations. Such high-stands, known globally in low latitudes, have never been credibly documented on the Gulf or on unglaciated Atlantic coasts. Lacking direct indications, numerous lines of indirect proof have been suggested. Proxy evidence was based on items as the reinterpreted geological record of NW Florida lakes, estuaries, and depositional conditions of Texas coast landforms. Pleistocene barrier sectors, barrier islands, relict foredune ridges, washover fans/flood-tidal deltas, and other sedimentary units and their morphology were claimed as highstand indicators. Unrealistically old or young radiocarbon and luminescence dates, the result of diagenetic changes and other contamination have resulted in questionable conclusions. A large body of sediment, stratigraphic and geomorphic data collected during two decades, including more recently obtained Holocene sea-level dates indicated the absence of mid and late Holocene marine high-stand stages on the Gulf. Late Holocene variations in coastal sediment supply, on the other had, are apparent from shore progradation-recession episodes on the SW Alabama and adjacent NW Florida coast.

One, recently revived school of thought proposes a step-like pattern of sea-level rise. Such prolonged stillstands that alternated with abrupt, large-amplitude sea-level rise episodes more recently were based on the genetic interpretation of broadly dated backstepping parasequences, emplaced in incised Pleistocene shelf valleys. Three loosely constrained multimillennial stillstands of 1.2–3.4 ka duration were inferred, each associated with a given Gulf paleoshoreline. These and postulated intervals of abrupt high-amplitude (1.5–6.0 m) sea-level rise conflict with the actual mid to late Holocene coastal development and sea-level history. The absence of backstepping parasequences in the incised Mobile Valley suggests that changes in sedimentation and erosion rates in such settings had greater impact on sequence development than sea-level changes had. Newly acquired information helped the formulation of a new regional sealevel curve that replaces two critical intervals in the old Nelson-Bray record. It conforms with more recently established sea-level histories in tectonically stable west Atlantic-Gulf areas, primarily Bermuda, the Bahamas, and Florida.

Along the north-Ecuadorian coast, characterized by high cliffs alternating with small plains in correspondence with river mouths, the Ensenada de Atacames, limited backwards by the Cordillera Costanera, consists mainly in a gently sloping surface falling between 3 and 10 m a.s.l., which was the site of an human settlement belonging to the “Atacames culture” (500 B.C.–1500 A.D.). This surface is interrupted seawards by a vertical cliff, subject to a rapid retreat. The pedo-stratigraphic study reveals it was built in a coastal brackish lagoon. The continental shelf facing Atacames is pointed out the presence of a carbonatic bank, remnant of an arrecife of late Pleistocene or early Holocene. As regard to the formation of the lagoon, one has to think to the genesis of a sandy barrier which isolated the waters of the Ensenada from the open sea. Since the Middle Holocene transgression is well known and sands are widely diffused on the carbonatic bank, one can infer that the genesis of the sandy barrier occurs because of their deposition and due to processes of littoral drift. The lagoon was probably formed just after the Holocene Climatic Optimum, by the development of a more and more stable sandy bar, which could have emerged around 3500 BP, during a recognized decrease of the sea level. After the colonization, the Atacames surface could become affected by erosional processes. Taking into consideration the present-day events, the most probable explication of the break of the external sandy barrier, which primed an erosional process, could have been the recurrence of strong ENSO (El Niñ o Southern Oscillation) events.

The current study was undertaken to identify major sources of contaminants and to explain the hydrochemistry of groundwater in relation to past landuse and borehole types in the reclaimed lands of Sydney's 2000 Olympic Games site, at Homebush Bay in Port Jackson. The shores of Homebush Bay, including some of the Olympic Games site, were reclaimed using an estimated nine million tonnes of domestic, commercial and industrial waste over several decades. The impact of this waste on groundwater was also investigated.

Groundwater (n = 101) and leachates (n = 4) samples collected in the reclaimed lands of the Olympic Games site were analysed for cations (Na, K, Ca, Mg) and anions (Cl, HCO₃, SO₄, and NO₃), and pH and electrical conductivity were also determined. The mean concentrations of Na, Ca, Mg, Cl and SO₄ in groundwater were more concentrated in reclaimed areas (infilled estuarine areas), followed by landfill areas (areas above sea level) and where least abundant in non-infilled areas because of saline intrusion and geographical approximation to creeks and the estuary to the Olympic site. The mean concentrations of K, HCO₃, NO₃ and values of electrical conductivity in groundwater were highest in landfill areas, followed by reclaimed areas and were lowest in non-infilled areas because these elements are related to anthropogenic influence. Groundwater in deep shale and in shallower saline (>10 ppt) reclaimed/infilled areas is dominated by sodium chloride, whereas non-infilled areas (<10 ppt) exhibit high sodium bicarbonate to bicarbonate and chloride compositions. Cation and anion contents of groundwater in the three types of boreholes investigated showed different hydrochemical characteristics. The order of mean abundance of major ions in ground-water in deep boreholes is Na≫Mg>Ca>K, while for anions it is Cl>SO₄>HCO₃>NO₃. The order of mean abundance of major ions in groundwater in shallow boreholes and standpipes is Na>K>Ca>Mg, while for anions it is Cl>HCO₃>SO₄>NO₃ and Cl>HCO₃>NO₃>SO₄, respectively. The relationship between total dissolved solid (TDS) and the sum of major element concentrations in deep boreholes, shallow boreholes and standpipes, indicates that these two types of groundwater underwent different geochemical evolutionary paths during circulation.

The Olympic Co-ordination Authority (OCA) implemented strategies, i.e. capping, excavation, and mounding and capping to remediate the Homebush Bay site before the Sydney 2000 Olympic Games.

Nitrogen limitation typically has considerable influence on plant community composition and structure on coastal barrier island dune ecosystems. The purpose of this study was to quantify plant community responses of different age dunes on a coastal barrier island in Virginia, USA to nitrogen addition. We hypothesized that nitrogen addition would increase density and cover, but with differential effects among species as a result of increased interspecific competition, and decrease species diversity. Density, cover and species diversity were monitored along a dune chronosequence on Hog Island (Virginia Coast Reserve Long-Term Ecological Research Site) over a seven year period. There were few significant changes in species dominance in control plots between 1992 and 1998; however, in fertilized plots, Ammophila breviligulata cover increased (except on the oldest dune) and Spartina patens cover decreased (except on the youngest dune). After seven growing seasons, results suggested more intense negative effects of competition in nitrogen-fertilized plots. Greater cover of Ammophila in fertilized plots suggests Ammophila is in a better position to compete for light with enhanced aboveground dominance. Diversity was lower in fertilized plots on all but the dune formed in 1967 and diversity decreased most dramatically in fertilized plots on the oldest dune. The increase in total density with fertilization as diversity decreased, coupled with the shifting composition of Ammophila and other dominants, appears to support the interspecific competitive exclusion hypothesis. Changes in the positions of free surfaces (groundwater level in particular) appear to influence plant community composition. The decline in Spartina density may be at least partially attributed to development of drier conditions on the older dunes.

The effective roughness of ripple beds under a wave regime is investigated. An existing numerical model, KU-2DVW-00, with a mixing length hypothesis is used to simulate the wave boundary layer flow over ripples. The ripple-length-average bed shear stress or form drag friction is obtained from integration of the computed pressure field. The wave friction factor is generally expressed in terms of the ripple profile shape, the ratio between the amplitude of wave orbital velocity, and the representative amplitude of bed shear stress. The effects of three factors, the bed form shape, orbital velocity amplitude over ripple length, ripple steepness on the wave friction factor or form drag are examined. Three bed profiles were tested. Results show that the drag force at the bed for the sharp-crested arc is much larger than for other shapes. The computed bed friction for the sharp-crested shape is about two times larger than that for the sinusoidal shape. Then, the effective roughness for the sharp-crested ripple becomes about 3 times larger than that for the sinusoidal shape. The model results also show that the effective roughness over ripple height is proportional to the ripple steepness up to a limit, and remains almost constant above the limit.

A video-based ARGUS coastal imaging system is being used at the northern Gold Coast, Australia to monitor and quantify the regional-scale coastal response to sand nourishment and construction of the world-first Gold Coast artificial (surfing) reef. This automated monitoring system is used to obtain hourly daylight images from four cameras that combined provide continuous coverage of 4.5 km of the coast. Digital image processing techniques are then applied on a routine (weekly to monthly) basis to extract a range of CZM information from the growing image database. Analyses include: the mapping of changing shoreline position (and hence beach width); the measurement of three-dimensional inter-tidal morphology and resulting changes in subaerial sand volume; and the comparison of wave breaking frequency at the reef and adjacent nearshore bars, to quantify enhanced recreational surfing opportunities at the reef site. Based upon the results of image analysis, to date (January 2003) an additional 20–30 m of net beach width was achieved along the approximately 2 km of nourished coastline, relative to the adjacent unnourished beaches to the north and south. Due to a regional net accretionary trend during this same period, in January 2003 the nourished beach at Surfers Paradise was some 50–80 m wider than at the commencement of the video monitoring program in mid 1999.

The dynamics of groundwater within beaches has implications for sediment transport in the swash zone and mass transport across the land-ocean boundary. Groundwater forcing by nearshore processes (e.g., wave runup, setup and ocean tides), and regional and local aquifer flows, result in the complex exchange of fresh and saline waters across the beachface boundary.

The new application of a cross-borehole resistivity imaging technique was used to observe the salinity structure along a 20 m shore-normal transect within the upper 3 m of an open-coast beachface. Several intriguing (and unanticipated) observations were made. These include the horizontal layering of saline and fresh pore-waters, the presence of salty water overlying fresh water, and evidence of significant advective/dispersive mixing, within a groundwater environment where the prevailing hydraulic gradients did not suggest this to be the case.

An advantage of the resistivity imaging technique over direct point sampling with spear points to extract pore-water, is that a dense and fully 2-D profile of the subsurface salinity structure can be mapped. The cross-borehole technique is intrusive in the sense that some disturbance is caused during installation, but this occurs only in the immediate vicinity of the vertical electrode strings, and post-processing is effective to remove the influence of these data. A high correlation achieved between measured bulk resistivity and fluid conductivity confirmed that the results of resistivity imaging can be used to calculate the pore-water EC (salinity), and hence the relative contributions from the adjacent freshwater aquifer and ocean sources. Though not attempted at the deployment described here, the burial of all electrodes also makes the technique suitable for examining the variation through time of saline-fresh pore-waters within the beachface.

There is a scarcity of data on the seedling establishment success of plants inhabiting the sand coasts of the Mediterranean, despite on increasing interest in the conservation and restoration of dune habitats. A field experiment, in conjunction with a series of laboratory germination tests, was conducted to (1) determine the recruitment capacity of Pancratium maritimum, a perennial dune plant which is declining along the north-western Italian coasts, by natural seed dispersal and (2) test the ability of seeds to tolerate different environmental stress. We planted seeds at different burial depths and found that seeds from greater depths (6, 10 and 15 cm) showed higher emergence (35.0–46.6%) than seeds from a shallower depth (2 cm; 11.6%). On average, less than 18% of seeds remained dormant at the end of the germination period. None of the seedlings that emerged in autumn survived over winter, and 88% of those that emerged in spring died by the start of the second reproductive season as a result of desiccation. Therefore, less than 3% of the seeds resulted in established seedlings. Under laboratory conditions seeds germinated well (87.5–100%) in darkness as well as at 12 h alternating light/dark and showed little dormancy (27–35 days). Germinability of seeds remained up to 70% for at last one year of storage. Temperatures below 10°C or over 30°C inhibited germination; frost and heat were lethal for most seeds. Germination was totally inhibited by salinity and water stress. Recovery of germination occurred in seeds from solutions below 25% seawater or −0.6 MPa. These data provide useful information for conservation and reintroduction of this species.

The sediment granulometry is a complex feature that requires studies and definition of parameters that go beyond a simple categorisation or classification. The grain size distribution frequencies may be analysed under a statistical approach, to establish parameters concerning the residual sediment transport. In estuaries, the sediment transport paths investigation is important to maintain navigation channels by dredging. Different methods based on grain-size parameters were developed to investigate these transport paths. These methods consider the spatial changes from three grain-size parameters: mean, standard deviation (selection) and skewness. In this work, we propose two alternatives to the one-dimensional (1-D) Sediment Trend Analysis (STA®), introduced by McLaren (1981). The first one is based on a non-parametric statistical test called Structural Exact Test (SET), which consider that each line memory has size not greater than one according to Lucio et al. (1999), where an asymptotic test was adapted for determining the order of a Markov Chain. Thus, observing the validity of all suppositions for the binomial distribution modelling checking the memory by means of the autocorrelation of the sequence or their difference, it is possible to implement the (SET). The second method is based on techniques of multivariate statistics like Principal Components Analysis (PCA) that allow us to associate the three-grain-size statistical parameters to create a characteristic index and concatenate their results to the difference sequences given the Autocorrelation Function (ACF). The ACF computes the autocorrelations of a sequential stochastic process. Autocorrelation is the correlation between observations of a sequence separated by k units. The Partial Autocorrelation Function (PACF) computes the partial autocorrelations of a sequential stochastic process. PACF, like ACF, are correlations between sets of ordered data pairs of a sequence. As with partial correlations in the regression case, partial autocorrelations measure the strength of relationship with other terms being accounted for. Based on the scope of Time Series the partial autocorrelation at a lag of k is the correlation between residuals at time t from an autoregressive model and observations at lag k with terms for all intervening lags present in the autoregressive model. The study area is based on the Westerschelde between Baarland in Holland and Rupelmonde in Belgium, where 867 sediment samples were collected by GeoSea Ltd, in 1993, for sediment trend analysis. These samples were used to check our methods: the SET and the PCA, comparing the results with the STA methodology. Our approach seems to be robust and offer a high efficiency results for a low computational cost in comparison with the classical and traditional one-dimensional sediment trend analysis.

During the winter of 1997–98, the El Niño weather pattern was a major influence on the beaches of the Gulf Coast of the Florida peninsula. Cyclonic storm patterns influenced by El Niño moved across the Gulf of Mexico from the southwest, approaching the coast of Florida from the southwest, a direction that differs from that of the usual winter frontal passage direction. The El Nino effects along the Florida Gulf Coast are in the form of subtropical, low-pressure systems including mild temperatures, frequent storms with sustained winds, high wave energy, and record amounts of rainfall. The winds and waves generated by these systems initially came from the south or west. As the storm passed over the coast, barometric pressure increased and winds shifted to the west or northwest. Ten occurrences of this weather pattern took place from late December 1997 through March 1998.

An atypical south to north littoral drift was recognized in localized areas along the Florida Gulf Coast during the winter of 1997–98, instead of the typical winter pattern of north to south sediment transport. Evidence for this reversal of sediment transport is the accumulation of sediment and shoreline progradation along the southern face of coastal structures and in a concave area that is oriented northwest to south-southeast. Waves due to the El Niño winter storms approached ebb-tidal deltas at the mouth of inlets from the west or southwest. Beach shorelines on islands located adjacent to the inlets responded differently than their normal winter response as recorded in surveyed beach changes. Beaches with a north-northwest shoreline orientation (between 330 and 345 degrees) had an increased rate of shoreline erosion and volume loss. Other effects of El Niño-influenced weather included erosion at typically prograding areas, and progradation or reduced rates of erosion in typically eroding locations. Such deviations from normal patterns are important factors to include in long-term beach management plans, especially if the El Niño phenomenon continues to be a frequent occurrence.

To examine the observations of fishermen regarding the impact of a hurricane on a mangrove forest of the Mexican Pacific, twenty-two structured interviews using an Analytical Hierarchy Process (AHP) approach were conducted in four villages of the Teacapán-Agua Brava lagoon-estuarine system. The local fishermen were asked to assess the likelihood that a mangrove tree would not survive a hurricane based on three attributes: main stem condition, diameter of main stem and species. The results suggest a high degree of consistency amongst the villages and with the observations of a previous investigation using the traditional scientific data collection methods. With few exceptions, the fishermen indicated that large diameter trees were the most susceptible to hurricanes. Conversely, that black mangrove (Avicennia germinans) and an intact main stem condition would indicate a better likelihood of surviving such an event. From the results of this investigation, it is suggested that the use of the AHP method can facilitate in the collection and interpretation of local ecological knowledge by scientists. Moreover, the output of this procedure, the vector of weights, can be used for comparison with scientific data collected by traditional means and for comparison with the observations of local peoples from other geographical locations.

Cambridge Gulf is a turbid embayment about 50 km long, with a mean water depth of about 12 m. The spring tidal range is 8 m. At its apex, the gulf divides into two estuaries, namely the West Arm that drains the mostly undisturbed Durack and Pentecost rivers, and the East Arm that drains the Ord River. As a result of a dam constructed in 1970 on the Ord River, the river flood regime has been greatly affected within the East Arm, having silted by an average of 3 m. By contrast the West Arm bathymetry has remained practically unchanged for the last 100 years. Oceanographic studies suggest that the West Arm exports fine sediment at a rate of about 40,000 ton d⁻¹, and that most of that sediment is now imported into the East Arm and does not reach Cambridge Gulf. Negligible net sediment flow was measured at the mouth of the gulf. This suggests that the pre-dam Cambridge Gulf received a total sediment inflow of about 100,000 ton d⁻¹, and about zero at present. Sediment is currently being redistributed within the gulf, the west coast may be accreting and the east coast receding.

Environmental magnetic data are now routinely used to investigate compositional variability of rocks, sediments and soils. Data from samples taken in the Gwendraeth Estuary, South Wales, U.K., demonstrate levels of intra-site and intra-sample variability in magnetic properties could be significant in field settings that show relatively limited inter-site variability. Care must be taken in both sampling at individual field sites and also in sub-sampling field samples within the laboratory prior to analysis. In contrast, duplicate measurements on individual samples show relatively low levels of instrument variability with the equipment used in this study.

Current measurements collected along the inner shelf off the central East Coast of India at seven stations during August–September 1988 are discussed. Data indicate a southerly flowing alongshore current, which occupies the whole of the water column over the inner continental shelf. The southerly flow was found to be continuous over the period of measurement except at the northern most station, where southerly flow was interrupted by short period reversals. The velocity of the southerly flowing alongshore current increases from north to south and reaching maximum off Madras (37 cm s⁻¹). Residual water circulation patterns show that there is an outflow of water to the south/south west from the entire water column except at the surface of the Stations 1 and 6. The mean kinetic energy and the eddy kinetic energy show direct relationship with the turning of the flow direction with depth. The energy associated is high if the turning of the flow with depth is more to the right and vice versa. The flow is normally opposed to the mean northeastward directed wind stress and it is thought to be associated with an alongshore pressure gradient. The source of this pressure gradient may be the large scale general circulation of the Bay of Bengal due to the influence of freshwater run off or it may be the result of some upstream or downstream forcing mechanism of a Munk layer driven Sverdrup flow due to wind stress curl.

The study region located north of Chennai city on the East coast of India is facing shoreline erosion/accretion related problems after the introduction of Ennore Port during 2001. For the present study 25 km of coastal stretch has been taken up, which comprises Ennore port region, natural sandy beaches of Kattupalli Island, which is a turtle breeding ground and Ennore Creek and Pulicat Lake inlets, with a total coastal settlement population of 25,000 people. After the introduction of breakwaters for the port, beach erosion and accretion are considered as critical problems, resulting in damages to the natural set up of the coastal region in the study area. Analyses of coastal dynamics and vulnerable zones of erosion and accretion along the coast were performed during the present study which are highly useful for the development of strategies for beach erosion/accretion management. Four major categories of shoreline changes were observed in the study region, viz., 1) Beach accretion south of Ennore Port, 2) Beach fill erosion north of north breakwater of Ennore Port, 3) Almost stable coastline at the central part of the study region and 4) Shifting inlet of Pulicat Lake. Quantitative analyses are made from shoreline survey using Real Time Kinematic GPS, beach profile survey in four identified transects, characteristics of environmental parameters such as tides, waves, currents and sediment nature in the near shore region. Long shore sediment transport was computed for four cells using numerical modeling package to quantify the changing littoral drift in study region. Results show reduction in sediment transport from −0.66 × 10⁶ m³/year on the southern side of Ennore port to −0.57 × 10⁶ m³/year on the northern side of Ennore Port.

This study evaluated the relationship between the traditional indicators of faecal pollution, Total Coliforms (TC), Faecal Coliforms (FC) and Faecal Streptococci (FS), and the presence of Salmonellae in coastal seawater in addition, the sensitivity of coliforms and streptococci tests was calculated. Finally, the detection of Staphylococcus aureus was evaluated as a possible additional parameter of coastal seawater quality. The 308 samples tested were drawn from the coastal seawaters along the Lecce-Brindisi shoreline (Apulia-Italy). In accordance with the Italian regulations (DPR 470/82), routine detection of Salmonella spp in seawater is only performed when poor hygienic conditions are expected, whereas S. aureus is not a routine parameter. Of the samples tested, 20, 56 and 20 were found unsuitable for TC, FC and FS, respectively. Salmonella spp were isolated in 22 samples. These 14, 7 and 13 had low or absent TC, FC and FS densities. S. aureus was isolated in 41 samples; 16 of these 41 cases were observed in July. Sensitivity was 36.4%, 68.2% and 41% for total and faecal coliforms tests and streptococci test, respectively. Faecal coliforms seem therefore to better predict the presence of Salmonellae in seawater compared with TC and FS. Our data show that the presence of Salmonella spp is not necessarily correlated with great concentrations of faecal pollution indicators; therefore, it would be advisable to always perform the detection of Salmonella spp beside the traditional indicators. We also suggest, in accordance with others authors, including the detection of S. aureus as a supplementary indicator for the prediction of coastal seawater quality and associated health risks.

Waves, currents, and longshore sand transport are calculated locally as a function of position in the nearshore region using process based numerical models. The resultant longshore sand transport is then integrated across the nearshore to provide predictions of the total longshore transport of sand due to waves and longshore currents. Model results are in close agreement with the I_l–P_l correlation described by Komar and Inman (1970) and the CERC (1984) formula. Model results also indicate that the proportionality constant in the I_l–P_l formula depends weakly upon the sediment size, the shape of the beach profile, and the particular local sediment flux formula that is employed. Model results indicate that the various effects and influences of sediment size tend to cancel out, resulting in little overall dependence on sediment size.

A shallow-water fish assemblage, over a soft, sandy bottom, at Canto Grande, Santa Catarina, Brazil, was sampled with a beach seine. Sampling was undertaken at 3 h intervals over 24 h on a bimonthly basis between April 1996 and February 1997. There was a seasonal variation in the number of species, density of fishes and biomass with the highest values in February (38 species, 257.6 fish 1000 m⁻², 2286.4 g 1000 m⁻²). A total of 67 species, belonging to 56 genera and 33 families were collected and the assemblage was dominated by seven species belonging to three families: Atherinella brasiliensis (Atherinidae); Brevoortia pectinata, Harengula clupeola and Sardinella brasiliensis (Clupeidae); Anchoviella lepidontostole, Cetengraulis edentulus and Lycengraulis grossidens (Engraulidae). Species diversity (H′) and equitability (J′) were medium to high throughout the year due to the low dominance. The largest change in the assemblage structure occurred between winter months (July and August) and the other seasons. None of the dominant species can be classified as a resident. Main predators were Pomatomus saltator (winter) and Trichiurus lepturus (summer). Most of the species observed were either juvenile fish or small pelagic and strongly gregarious species.

Terrestrial methods that may be used to quantify cliff erosion rates, and to qualify the real status of coastal areas currently zoned for building are described. The methods are fast, inexpensive and effective for relatively small terrains. Due to the use of modern methods and instruments, a very high (sub-centimetre) accuracy for measuring cliff recession can be reached. A computer model is derived to analyse data obtained through the measurement techniques. The model will, over time, supply data sufficient to project short to medium term volumetric changes in rock mass and will provide significant input in the development of a coastal hazards zoning protocol. A pilot study has been carried out in North Shore City (Auckland, New Zealand).

A theoretical treatment paving the way for computing the discharge through aquifers using the rigorous equations of fluid mechanics instead of the semi-empirical Darcy's law.

This paper examines the feasibility of using LIDAR surveys to update existing historical shoreline data sets by comparing contour shorelines and the high water line (HWL) at eight study locations in North and South Carolina. The analysis was based on airborne LIDAR topography and orthoimagery collected simultaneously during June 2000. The popular method of digitizing the wet-dry line from orthoimagery was used to measure the HWL. Contour shorelines were derived by using the previous high tide (HW), the mean high water datum (MHW), and the mean higher high water datum (MHHW) of nearby tide gauges. A method was developed to quantitatively compare the positions of the HWL and the contour shorelines in a GIS. The mean high water and mean higher high water contour shoreline positions were the best match to the high water line at 7 of 8 locations, and differed by less than 5.4 meters from the digitized high water line positions. This difference is well within the errors associated with past methods for measuring shoreline position. Therefore, it is deemed practical to use LIDAR data to estimate the HWL.

As a contribution to the UNDP/GEF project ‘Environmental Protection of the Río de la Plata and its Maritime Front’, the three-dimensional primitive equation Hamburg Shelf Ocean Model is being implemented for forecasting purposes. As a first step a study of the tidal propagation was done. Data for the estuary were gained through a set of three one-way nested models. Simulations were started with a large-scale model covering the Argentinean and Uruguayan and part of the Brazilian continental shelves. This model provides boundary conditions to a smaller scale model of the Río de la Plata and adjacent continental shelf, which in turn is used to force a small-scale high-resolution model of the Río de la Plata estuary. Model sensitivity to different boundary conditions and to model parameters was investigated. Solutions are not sensitive to the two different boundary conditions tested, derived from global data assimilating models. It results also not sensitive to lateral diffusion but to bottom friction. M₂ tidal wave propagates northwards as a Kelvin wave, with amplitudes reaching almost 4 m in Southern Patagonia and a few centimeters at the Río de la Plata estuary. Simulation results for the M₂ component propagation were validated using all tidal gauge data available and several currents observations, resulting in a very good agreement. These simulations have permitted, therefore, the construction of more reliable model derived cotidal, corange and tidal currents charts. The nonlinear transfer of energy from semidiurnal to higher order harmonics was mapped. It can reach very high values at some locations of the Patagonian coast. Tidal energy dissipation derived from the simulations shows that it constitutes an important amount of the globally estimated one.

The need for a cautious interpretation of results from an analytic method for an analysis of the stability of tidal inlets is illustrated by comparing theory with data from St. Andrew Bay in Florida's panhandle. Historically this bay was connected to the Gulf of Mexico by East Pass at the eastern end of the bay. However, following the opening of St. Andrew Bay Entrance in 1934 at the western end to serve Panama City, the flow cross-section of this channel increased while East Pass contracted gradually and eventually closed in 1998. In December 2001 East Pass was reopened by dredging a small flow-relief channel. These events provided the opportunity to apply the stability analysis to the newly-formed two-inlet one-bay system. Interpretation of the results in terms of observed inlet stability versus prediction is shown to be contingent upon knowledge of the history of channel maintenance and the morphodynamics of the bay. The illustration underscores the need to apply the method in pre-project engineering investigations of the long-term impact of opening a second inlet in a bay.

The Canopic branch, the largest relict Nile distributary, once flowed across the NW Nile delta of Egypt to the Mediterranean. This study focuses on the Canopic's evolution at the delta margin and in Abu Qir Bay seaward of the coast. Information from historic documents, integrated with data from geographical, geological, and archaeological exploration in the bay, indicates that the Canopic distributary was active from ∼4000 B.C. to the end of the 1st millennium A.D. Fluvial discharge persisted through pre-Dynastic, Dynastic, Greek, Roman, Byzantine and early Arabic time. The channel flowed to two sites, Herakleion and Eastern Canopus, established by the Greeks as navigational gateways for trade in the delta and surrounding region. Eastern Canopus functioned until the mid-8th century A.D. At that time, flow in the Canopic had decreased markedly, and Nile water was diverted to the east, through the Bolbitic-Rosetta branch. By the end of the first millennium A.D., Nile water was channeled in the Rosetta and Damietta distributaries, and the Canopic branch eventually converted to a canal and drain system.

The Canopic promontory across which the branch flowed, and the 2 ancient sites located at the promontory coast near Canopic channel mouths, subsided beneath the waters of the bay after the 8th century. Submergence was a response to interaction of eustatic sea-level rise, annual floods, growth-faulting, soft-sediment deformation and other natural processes. As the Canopic promontory subsided, Abu Qir Bay attainted a marked concave-seaward shape and its shoreline shifted southward. This geoarchaeological investigation helps distinguish the long-term impact of natural events from that of increased human activity. This distinction is of practical importance for the highly populated and vulnerable delta margin that continues to experience submergence and erosion.

Restorations of barrier islands can be beneficial to coastal marshes, but may also have detrimental effects on intertidal macrobenthic communities. Two barrier islands of the Isles Dernieres chain of Louisiana were recently renourished with dredged sediments taken from the adjacent estuary. This study addresses the impact of beach restoration on intertidal populations of the burrowing ghost shrimp, Callichirus islagrande. We compared sediment characteristics of the restored sites and neighboring sites (both with and without shrimp) and examined the effect of sediment alteration on recolonization rates. Beach height was increased by an average of 2.4 m. Differentiation among sites with respect to silt/clay, sand, and gravel fractions was significant (P<0.001). East Island, the primary site of restoration, had the largest proportion of silt/clay sediments (40 % of total) whereas Trinity Island had the largest proportion of gravel (12 %). Minimal population recovery (total = 3 individuals) was evident 2 years post-restoration. High levels of silt/clay loading at East Island appear to have slowed population recovery.