Optically stimulated luminescence (OSL) dating of quartz grains extracted from beachrock on the southeast coast of India was attempted. Preliminary OSL ages of beachrock indicate that during the Late Holocene (3.6–2.1 ka) sea level along this coast was higher than at present. This observation is broadly consistent with the existing data based on radiocarbon dating of bioclasts in the beachrock, which suggests a higher sea stand during 4.3–2.3 ka. This study demonstrates the potential of optical luminescence dating of beachrock for refining sea-level chronology and shoreline evolution on the southeastern coast of India.

Aspects of northern Gulf of Mexico (NGOM) (Louisiana, Mississippi, Alabama, and Florida panhandle) processes and barrier islands that are pertinent to their geomorphologic response are contrasted with the broader knowledge base summarized by Schwartz (1973) and Leatherman (1979, 1985). Salient findings from studies documenting the short-term (storm-induced; timescales of hours, days, and weeks) and long-term (timescales of years, decades, and centuries) response of barrier island systems in the NGOM are synthesized into a conceptual model. The conceptual model illustrates the hypothetical evolution of three barrier island morphologies as they evolve through a typical Category 1–2 hurricane, including poststorm recovery (days to weeks) and long-term evolution (years to decades). Primary factors in barrier island geomorphologic response to storms, regardless of location, are the elevation of the island relative to storm (surge plus setup) elevation, and duration of the storm. Unique aspects of the NGOM barrier islands, compared with knowledge summarized for other barrier types, include (1) storm paths, wind speed, and large bays that create the potential for both Gulf and bayshore erosion and (2) in Louisiana and Mississippi, the potential for loading of the underlying substrate by the barrier island, which, through time, increases consolidation, relative sea level rise, overwash, morphologic change, and migration. We recommend that design of large-scale beach restoration projects incorporate the potential for (1) time-dependent consolidation of the underlying sediment due to project loading and future migration, (2) Gulf and bayshore erosion and overwash, and (3) eolian transport toward the Gulf from north winds.

Croton punctatus N. von Jacquin is a New World tropical and subtropical dioecious, rhizomatous, subshrub or herb with apetalous flowers that is common on coastal beaches. Herein, we present a review of the biology of this important pioneer species. Large colonies of C. punctatus promote embryonic dune formation in belts parallel to the shoreline. Colonies act to intercept wind-transported sand. Colony success is related, in part, to a large seed bank and a relatively high germination potential. Other factors contributing to successful colonization include tolerance of sand scouring, salt spray deposition, burial, high substrate temperatures, and low levels of soil nutrients. Its northern distribution limits appear to be determined by the frequency, duration, and severity of freezing temperatures. Transplanted seedlings have relatively high survival rates. Therefore, C. punctatus has been useful in stabilizing sandy dredged material.

The Loxahatchee River, a 500 km² watershed on the southeast Florida coast, is a barrier-impounded drowned river valley experiencing rapid urbanization during the past 50 years. The estuary is currently composed of a sandy central basin with bifurcating forks accumulating organic-rich muddy sands. The Northwest Fork drains natural forest, residential, and agricultural catchments and has a much larger bayhead delta than the channelized Southwest Fork, which is only 50 years old and diverts much of the flow from the Northwest Fork. Sediment accumulation rates within muddy sand deposits are about 2–3 mm a⁻¹, commensurate within error of the current rate of local sea-level rise. Previously established Holocene accumulation rates are close to relative sea-level rise, implying that sediment accumulation is in equilibrium with the creation of accommodation space. The main anthropogenic influences have been changes in surface sediment texture corresponding to dredging-induced modification of tidal currents and a localized >threefold increase in sediment accumulation rate supplied by sources local to the estuary. Late Holocene sedimentation has been episodic, and lithofacies vary from bioturbated transgressive sands at depth to peat and laminated fine-grained sediments then back to mottled muddy sands in the uppermost strata. This facies transition is attributed to a change of water column stratification conditions caused by decreased tidal flushing in the estuary possibly brought about by variation in sea level or episodic inlet closure by littoral sand transport. The magnitude of the anthropogenic changes in sedimentation is roughly equal with natural changes in lithofacies formation.

Mangrove stands and seagrass beds grow along the coasts of the United Arab Emirates (UAE). These marine plant species are concentrated in specific tidal zones along sheltered intertidal coastlines in association with estuaries and lagoons; mangroves fringe the coastline encroaching into the lower intertidal region, whereas seagrasses populate the adjacent deeper water. In most cases, the distribution of mangroves and seagrasses does not overlap. It is important to monitor the geographic extent and health of mangrove forests and seagrass beds, which serve as an important habitat for juvenile marine species. Remote-sensing data for the Khor Al Bazam area in the vicinity of Abu Dhabi, UAE, covering the years of 1994, 2000, and 2003, were used to determine the change in mangrove and seagrass cover. Since 1994, there has been an increase in mangrove cover, likely because of plantation activity, the closure of nearby shipyards, and an increase in public awareness regarding mangrove preservation. Although more difficult to determine, a combination of remote sensing and ground-truthing indicates that the seagrass beds within the study area have likely increased in real extent over the same time period.

This paper is the result of the analysis of several studies made by the Autonomous National University of Mexico (UNAM) (during 1989–1991) and by the Federal Commission of Electricity (CFE) (during 2000–2001 and 2003) since hurricane Gilbert hit the Yucatan Peninsula (1988). The analysis was finished at the end of 2004 with the development of a hydrodynamic and morphodynamic model of the littoral system. These studies were looking for a solution to the erosion suffered by the Cancun littoral barrier (“island”) and to obtain a good understanding of the littoral dynamic processes in the barrier of Cancun-Nizuc. Although the erosion of this barrier only became obvious after Gilbert occurred, there is evidence to conclude that the hurricane effects are not the origin of the erosion. The hurricane only worsened a process that existed for a long time, probably due to the inadequate and excessive occupation of the beach front that reduced the capacity of recovery (“resilience”) of the beach profile. Different measures were taken to protect the zone, but they soon failed; the erosion continued and hurricanes Ivan and Wilma worsened the conditions of the whole barrier. Finally, the recovery of the barrier was tackled by means of sand nourishment. This nourishment has been completed in June 2006 in parallel with the drafting of this paper.

Portugal is one of many countries in the world that suffers from coastal erosion. Conventional ways of protecting a coastline appear to entail some disadvantages. An innovative and interesting way of protecting a local coastal zone by means of multifunctional artificial reefs avoids some of them. A multifunctional artificial reef is a submerged breakwater which, besides helping to protect the local coastline, can have other purposes; in particular it may enhance the surfing possibilities and the environmental value of the local area. The structure has several positive side effects: first, it provides an unimpaired visual amenity; second, it offers tourist and economic benefits by improving the surfing conditions. A preliminary design, achieved step-by-step, is proposed for a multifunctional artificial reef making use of the theory and state of the art multifunctional artificial reef design, a preliminary design, achieved step-by-step, a priliminary design is proposed. The proposed reef geometry, together with numerical and physical tests, allows the analysis of a multifunctional reef breakwater designed to protect a stretch of the northwestern coast of Portugal. Taking into account the condition that the proposed geometry will only function properly on a sea slope bottom of less than 1 : 50, the main choices are as follows: the upper part of the structure is delta shaped with an angle of 66° and a side slope of 1 : 10, and the lower part consists of a platform whose slopes are as steep as possible. The position of the reef should be such that the distance from the apex of the structure to the undisturbed shoreline is greater than 1.5 times the natural surf zone width.

The experience acquired in the Prestige crisis management has demonstrated the importance of forecasting oil slick trajectories to plan an effective oil spill response. To have a reliable prediction system, we need to perform a detailed calibration and validation of the oil spill transport model. In this work, the Lagrangian transport model, PICHI, developed by the University of Cantabria during the Prestige accident, is calibrated by means of an automatic calibration methodology. The shuffled complex evolution method, developed by the University of Arizona (SCE-UA), is applied to estimate the optimal coefficients of the model. The calibration of the model has been carried out using 13 buoys deployed in the Bay of Biscay during the Prestige accident as well as coetaneous meteorological and oceanographic data. Moreover, reanalysis data collected in the Spanish ESEOO project framework has also been used. Results suggest that buoys outside the continental slope were mainly driven by wind, whereas ocean currents played an important role in the motion of the buoys located over the continental slope and shelf. According to these findings, the final calibration of the coefficients is performed considering different buoy data. The methodology applied to this broad buoy database, has allowed us to calibrate the model, taking into account the relative importance of the forcings in buoy movement as well as the dynamics associated with each area.

Two probable zones of submarine groundwater discharge (SGD) from the SW coastal zone of India are reported. They lie between the prominent coastal promontories, namely Kovalam in the Thiruvananthapuram district of Kerala state and Muttam in the Kanyakumari district of Tamil Nadu state. The purpose of characterizing such groundwater leakage zones, in general, is (i) to assess the optimum exploitation levels of coastal fresh groundwater; (ii) to locate feasible waste disposal sites in the coastal zone, and (iii) to estimate seaward pollution transport levels. Indirect indications on the basis of satellite digital data analysis, systematic fieldwork, physicochemical water quality checks, and also resistivity surveys have been utilized to understand the nature of groundwater movement in the coastal aquifers. Geomorphological settings, temporal water quality variations, and subsequent determination of hydrochemical facies have provided evidence for explaining the phenomenon of SGD. In particular, the indications of streaming potential, inferred interface geometry patterns, and truncated lithological layering point to the presence of ground-water discharge across the recognized sections.

The coastal zone in the Red River Delta of Vietnam is under large threat due to fluvial flooding, coastal flooding, and coastal erosion. As an important input for ongoing studies that focus on finding an optimal coastal protection strategy for reducing the vulnerability of the coastal region, this paper aims to describe the current situation of the coastal region and assess its present protective measures. In the region, sea dikes have been used as the predominant countermeasure with two intended functions: (i) protecting low-lying areas from coastal flooding and (ii) reducing the risk to the hinterland caused by erosion. However, the sea dikes seem not to function well and are insufficient to withstand dike breaches at the low frequency they are designed for. To have better insight into the actual situation of the whole system, this paper first investigates the historical development of the coastlines in the delta based on available information. Second, hydrodynamic and morphological processes of the coastal and estuarine systems are reviewed and further analysed. An effectiveness assessment of the present protection strategies is subsequently presented. Finally, further research needed to improve the rehabilitation of coastlines and the safety of the region is discussed based on analysis results.

Marine stingers hospitalize approximately 100 people annually in tropical Australian waters, and are known to have caused at least 73 fatalities. Elsewhere in the tropical and temperate seas of the world, marine stingers pose a similar threat to human safety, and reported sting numbers are on the rise. Lycra body suits (“stinger suits”) have been used for stinger protection since the early 1980s, but have not been formally tested as a barrier against Irukandji (Carukia barnesi) tentacles. Other products are being used and developed; however, no safety standards currently exist for this widely used form of protective equipment. Eight products were tested with live C. barnesi: a Lycra stinger suit used by Surf Life Saving, a product developed by ROBIS Pty. Ltd. and marketed as “The Stinger Suit”, three different styles of nylon pantyhose, two sport products designed to “wick away” moisture and keep the wearer cooler, and a 0.5-mm neoprene wetsuit. Products were evaluated for seven common concerns relating to safety and practical wearability. Primary concerns, i.e., those relating to performance of the fabric in preventing stings, include: ease of penetration by jellyfish tentacles, adherence of tentacles or body to fabric, and potential for crushing through the fabric. Secondary concerns, i.e., those relating to overall usage as stinger-preventative clothing, include: durability or integrity of the barrier, whether the product is available as a one-piece garment, heat-retention properties, and product cost. In general, the tighter the fabric weave, the better tentacle exclusion, and the smoother the fabric, the more resistant to adherence. Lycra is vulnerable to crushing of tentacles through the fabric, but appears to be the best choice for routine-use stinger-protective clothing. Recommendations are made for safe use of protective clothing, as a basis for development of an Australian Standard in protective clothing for marine stinger safety.

This paper documents a novel procedure for assessing the vulnerability of an open-coast dune system to tsunami hazard. Geographic Information System (GIS)–based analyses of Light Detection and Ranging (LIDAR) data are employed to classify a range of dune topographies in terms of four tsunami inundation scenarios, run-up to 3, 6, 8, and 10 m above mean sea level, along the coast of Christchurch, New Zealand.

Analysis reveals two key characteristics which together define the tsunami vulnerability of a narrow vegetated dune system: (i) the elevation or average height of the dune ridge and (ii) the continuity or standard deviation of height of its longshore profile. We find that the Christchurch dune coast currently offers a high degree of protection against inundation from small to medium tsunami (run-up ≤6 m above mean sea level), with the degree of vulnerability under more extreme scenarios varying longshore in relation to the height and continuity of the dune system and its vegetation.

A tsunami inundation vulnerability index is developed to assist coastal managers in quickly assessing the relative vulnerability of sections of dune, while simultaneously identifying the nature and location of weaknesses. At the local level this index may be used to effectively allocate management resources, while at a regional level it can be used in coastal development and hazard planning. Relative to current field survey–based methods of determining tsunami inundation risk, the GIS-based procedures and vulnerability index developed here offer significant improvements in accuracy and efficiency at local to regional scales.

For calculating subsidence rates along the Nile Delta coastal margin, archaeological site data provide more accurate temporal and elevation control relative to Holocene sea levels than chronostratigraphic analyses of radiocarbon-dated sediment cores. Recently acquired data on the depth and age of 11 buried and/or submerged levels of human activity at seven ancient sites serve to calculate average annual rates of subsidence along the northern Nile Delta margin during the middle to late Holocene. Subsidence rates range from 0.9 to 4.3 mm/yr, varying irregularly from west to east along the northern delta coast, and averaging ∼2.5 mm/yr for 11 data points on the margin as a whole.

Subsidence rate is directly related to thickness of sediment section, with highest values in the eastern part of Manzala lagoon and at coastal promontories of the Damietta and Rosetta branches. This, in large part, is a function of underlying sediment compaction plus sediment loading and readjustment of strata at depth. Short-term natural events such as earthquakes, tsunamis, Nile floods, and winter storm surges also serve as triggers of subsidence. An additional important factor is human activity, such as construction of large structures on water-saturated substrates. Most modern towns along this increasingly populous delta margin are located in low-lying vulnerable settings presently subject to subsidence, a phenomenon that warrants close monitoring and increased implementation of protective measures.

Measurements of longshore sand transport, wave breaker height, longshore current velocity, and water temperature and salinity were carred out on a subarctic beach under varying water temperature conditions during summer and fall. Water temperature during summer varied from 9°C to 17°C, while temperature ranged from −1.75°C to 1.25°C during the fall experiments. During periods with low water temperatures, considerably higher rates in both bedload and suspended sediment transport were observed compared with the results obtained during summer with similar wave heights and current velocities. The increase in suspended sediment transport associated with low water temperatures is likely due to lower sediment fall velocities resulting from significant increases in fluid kinematic viscosity, which ranged from 1.1 to 1.37 × 10⁻⁶ m² s⁻¹ in summer and from 1.74 to 1.92 × 10⁻⁶ m² s⁻¹ in the fall. Less but still significant increase in bedload sediment transport in cold water is interpreted to be the result of temperature-induced variations in fluid viscosity that affect turbulence and boundary layer dynamics as well as bed configuration. Frazil ice occurred on some occasions during the fall experiments, but with the small number of samples collected when frazil ice crystals were present in the water column, it was not possible to establish a relationship between sediment transport rates and the presence or absence of ice. Our results nevertheless indicate that in cold climate regions extremely low water temperatures may cause a substantial increase of coastal sediment transport.

Climate change exerts pressure on the coastal zone by altering sediment supply from the hinterland and rising sea levels. Human activity affects the dynamics of the coastal zone as well. Both natural and human-induced changes in variables that govern coastal dynamics have a profound effect on the long-term and large-scale evolution of the coastal zone. In this paper, we introduce a concept that addresses the components relevant in sustainable integrated coastal zone management. We illustrate that quantifying sediment budgets in the coastal zone might improve our understanding of long-term (>100 y) coastal evolution. The increasing attention within sustainable coastal management on sensitivity analyses of climate change impacts and socioeconomic activities in the coastal zone implies an increasing demand of probabilistic scenarios of coastal evolution spanning a time interval of ∼100 years. Within probabilistic scenarios of coastal evolution, the quantification of the coastal sediment budget cannot be discarded.

Coral reefs, the foundation and primary structure of many highly productive and diverse tropical marine ecosystems, have been degraded by human activity in much of the earth's tropical oceans. To contribute to improved understanding of this problem, the potential relation between river sediment and nutrient discharges and degradation of coral reefs surrounding Puerto Rico was studied using streamflow, suspended-sediment, and water-quality data. Mean annual runoff for the 8711 km² island is 911 mm, about 57% of mean annual precipitation (1600 mm). Mean annual suspended-sediment discharge from Puerto Rico to coastal waters is estimated at 2.7–9.0 million metric tonnes. Storm runoff transports a substantial part of sediment: the highest recorded daily sediment discharge is 1–3.6 times the mean annual sediment discharge. Hurricane Georges (1998) distributed an average of 300 mm of rain across the island, equivalent to a volume of about 2.6 billion m³. Runoff of more than 1.0 billion m³ of water and as much as 5 to 10 million metric tonnes of sediment were discharged to the coast and shelf.

Nitrogen and phosphorous concentrations in river waters are as much as 10 times the estimated presettlement levels. Fecal coliform and fecal streptococcus concentrations in many Puerto Rico rivers are near or above regulatory limits. Unlike sediment discharges, which are predominantly episodic and intense, river-borne nutrient and fecal discharge is a less-intense but chronic stressor to coral reefs found near the mouths of rivers. Negative effects of river-derived sediment and nutrient discharge on coral reefs are especially pronounced on the north, southwest, and west coasts.

Coastal dune systems are very sensitive geoindicators that reflect rapid geological change and its environmental consequences. Detailed analysis of the long-term trends in the dynamics of the shifting Holocene dunes using satellite images and ground survey data revealed that during the 20th century, erosion, flattening, and sylvanization of the dunes along the entire 33-km length of the still-active Great Curonian dune ridge was taking place at a very rapid rate and scale. Flattening of the shifting dune ridge because of exhaustion of sand supplies, plant succession, and human activity is the main dune management problem, important both for the maintenance of landscape diversity and for the conservation of the traditional heritage features of the Curonian Spit as a World Heritage site. A radical shift in dune-handling paradigm—from forestation to the removal of pine plantations—and the enhancement of dune dynamism is critically needed for the protection of the Great Curonian shifting dune ridge.

An investigation of the effects of bottom topography on the run-up height of vertical structures in protecting from destructive oceanic long waves, such as tsunamis, was conducted by using an analytical solution derived from the continuity and momentum equations. Because the solution of the governing equation is expressed as a Bessel function in cases where the water depth varies linearly, the present solution was obtained by assuming the water depth as a series of constant slopes. The present solution was verified by comparing with an analytical solution derived previously. The reflection of waves and the effects of bottom topography on the run-up height of vertical structures that partially reflect waves were investigated.

Based on sedimentology, geochronology, palynology, and diatom analyses from core silt sediments in Cassino Beach (32°11′06″ S and 52°09′45″ W), southern Brazil, the Holocene marine transgressive stage was established. The absolute age of one sample is about 4940 ± 80 years BP. The palynomorphs (pollen and spores of vascular plants, zygospores and colonies of Chlorophyceae, cysts of dinoflagellates and acritarchs, fungal spores, and microforaminifera), silicoflagellates, and diatoms indicate the presence of an inlet bay in the southern part of the coastal plain during the marine transgression. The changes in the taxonomic composition, abundance, and frequency of palynomorphs and diatoms from the samples corresponding to transgression show an oscillatory character of the sea level. The posterior marine regression resulted in sand deposition and dune formation. The results demonstrate the importance of palynomorph and diatom application for the palaeoenvironmental reconstructions in coastal plains.

In 1992 the entrance channel through the tidal inlet to Tauranga Harbour, which is located along the Bay of Plenty littoral drift system, was deepened from 10 m to 14 m. The deepened channel has become a sediment trap for littoral drift bypassing and tidal current driven sediment transport through the inlet. Since 1992, there has been an increase in maintenance dredging requirements at the inlet, because of sand accumulation along the southeastern border of the entrance channel. Previous studies have identified an ebb tide–induced eddy operating on the eastern side of the ebb-jet as it exits the tidal gorge. In this article, the eddy system has been simulated with a validated two-dimensional hydrodynamic model, detailing time-varying current patterns over the ebb-tidal delta. Particular emphasis is placed on defining the trajectory of the eddy and evaluating its influence on the observed sedimentation patterns. The model results indicate the formation of opposing eddies on either side of the entrance channel, both of which are transient in nature. The centre of the eastern eddy propagates seaward along the downdrift margin of the entrance channel as the ebb-jet lengthens. Bathymetric survey residuals between 2004 and 2006 confirm significant accumulations of sediment along this downdrift margin. The evidence is consistent that the eddy system exerts a directional control over transport of sediments entrained by waves over the ebb-tidal delta.

This article describes the testing and calibration of a digital video camera system used to measure surface moisture over a section of beach extending tens of metres alongshore using the brightness of the sand surface. The system consisted of two networked video cameras mounted on a mast on the foredune crest about 14 m above the beach surface and oriented obliquely alongshore in either direction. Photographs and video clips were stored on a notebook computer. Over a period of 4 weeks in May and June 2006, a series of field tests was carried out; these tests were designed to calibrate the surface brightness recorded at locations visible in the digital images against gravimetric surface moisture measured by scraping the surface at the same location. While there was a significant correlation between surface brightness and gravimetric moisture content, the strength of this relationship was improved by normalising against a white board present in the field of view of the camera. An even stronger relationship was obtained by normalising against an area of dry sand present within a portion of the photograph. Rectification of the images and application of the calibration equation permitted mapping of surface moisture variations on a timescale of hours to days. The approach appears to provide a useful means of estimating surface moisture on the beach on a scale of tens of metres and over timescales of seconds to months.

Subtidal marine sediments from the Belgian continental shelf were measured using laser diffractometry and dry-sieving techniques. The laser diffractometry approach provided a coarser and less-sorted particle size distribution, compared with the dry-sieving technique. The 5th, 10th, 16th, 50th, 84th, 90th, and 95th percentiles, 180–710 μm cumulative mass/volume percentages, mean grain size, and sorting measured using both techniques were correlated, with r² > 0.76 (p < 0.001). Skewness and kurtosis were poorly correlated between both techniques. For the purpose of conversion of data from one type of measurement to the other, for sandy sediments a global approximation can be obtained with the proposed relationships.