Without sea-level acceleration, the 20th-century sea-level trend of 1.7 mm/y would produce a rise of only approximately 0.15 m from 2010 to 2100; therefore, sea-level acceleration is a critical component of projected sea-level rise. To determine this acceleration, we analyze monthly-averaged records for 57 U.S. tide gauges in the Permanent Service for Mean Sea Level (PSMSL) data base that have lengths of 60–156 years. Least-squares quadratic analysis of each of the 57 records are performed to quantify accelerations, and 25 gauge records having data spanning from 1930 to 2010 are analyzed. In both cases we obtain small average sea-level decelerations. To compare these results with worldwide data, we extend the analysis of Douglas (1992) by an additional 25 years and analyze revised data of Church and White (2006) from 1930 to 2007 and also obtain small sea-level decelerations similar to those we obtain from U.S. gauge records.

To plan for wetland protection and sensible coastal development, scientists and managers need to monitor the changes in coastal wetlands as the sea level continues to rise and the coastal population keeps expanding. Advances in sensor design and data analysis techniques are making remote sensing systems practical and attractive for monitoring natural and man-induced wetland changes. The objective of this paper is to review and compare wetland remote sensing techniques that are cost-effective and practical and to illustrate their use through two case studies. The results of the case studies show that analysis of satellite and aircraft imagery, combined with on-the-ground observations, allows researchers to effectively determine long-term trends and short-term changes of wetland vegetation and hydrology.

The accurate characterization of coral reef habitats not only supplies invaluable data to marine researchers but also provides conservation managers the necessary information to protect these fragile ecosystems. Without accurate in situ documentation of benthic coral reef communities, the general health, as well as the effects of stressors on these habitats, cannot be correctly quantified for scientific evaluation. In this study, the benthic ecological assessment for marginal reefs (BEAMR), a comprehensive monitoring protocol for reef characterization, was applied to a nearshore coral reef system in the southeast region of the Gulf of Mexico to determine if the condition of the habitat had negatively altered over the study's duration. BEAMR data sets were collected in three separate sampling events over 5 years, with sampling scheduled around an experimental application of beach compatible sand adjacent to the study area. The results from PRIMER-E v.6 statistical analyses showed that the marine reef community as a whole (i.e., integration of all benthic functional groups) was not negatively affected throughout the study's duration. Additionally, parametric statistical analyses showed that the coral reef habitat in this Gulf region did not sustain significant influxes of sediment or adverse effects to the biota, but rather showed a significant increase in stony coral colony size and cover over time. Overall, it was determined that the condition of this reef resource has maintained a positive level of sustainability during this study, and by using the BEAMR method, marine biologists were able to statistically quantify the health of a coral reef system. Even so, the vulnerability of reef resources remain, which is why specific habitat assessment protocols, such as the BEAMR method, help support the worldwide conservation of coral reef communities. By aiding in the quantification of reef health, BEAMR can help identify and characterize potential reef effects from both natural and human pressures.

Batis maritima C. Linnaeus (maritime saltwort) is a New World subtropical and tropical trailing subshrub that forms dense colonies in salt marshes, brackish marshes, and mangrove swamps and frequently is found on the margins of salt pans and wind-tidal flats. It typically occurs at elevations less than 1.0 m above mean sea level and at sites where salinity ranges from 18 to 50 ppt. Leaf succulence increases significantly in the dry season and leaves are shed, thereby reducing salt-induced stress. Batis maritima occurs in sites normally subject to minimal sand coverage. However, wrack deposits stimulate growth. Maritime saltwort provides cover and nesting sites for some species of birds, but glucosinolate compounds in shoots make the plants unpalatable to most large vertebrates, with the exception of marine iguanas in the Galapagos Islands. Recently, B. maritima is proposed to have a major role in reducing ozone levels in the stratosphere.

Florida (United States) beaches serve as globally important nesting habitat for protected species of sea turtles. Following coastal development, portions of this habitat have become inaccessible to nesting sea turtles due to coastal armoring and other barriers. To assess nesting habitat quality, we randomly selected beaches totaling 80.45 km in each of four regions of Florida (northeast, southeast, northwest, and southwest) and surveyed them for potential barriers to nesting during the period of April 2001 to May 2002 (total surveyed coastline  =  321.8 km). Potential barriers to nesting were found in 78 forms on sampled beaches, including seawalls, revetments, sand bags or tubes, sand fences, access structures, recreational equipment, and buildings. We determined the position and extent of structures using a differential global positioning system. Surveyed beaches made up 24.5% of Florida's sandy coastline and were sampled to be regionally representative. In an assessment summed for all regions, potential barriers to nesting occupied 18.0% of the total surveyed beach length. The region with the greatest extent of potential barriers was southeast (23.8%), followed by southwest (21.7%), northwest (14.1%), and northeast (12.3%). Seawalls were the most common potential barriers in all but the northwest region, where sand fences were most common. Our measurements did not include structures that were hidden from view by sand or other structures. Following coastal effects from four major hurricanes that made landfall in 2004, we resurveyed 16 km of beach in each region (total  =  64 km). We recorded a net reduction of sand fencing in northeast and northwest Florida and a net reduction of revetment rocks in the southwest region due to covering by sand. However, the linear extent of barriers increased in northeast and southwest due to seawall construction and additional sand fencing.

Tidal variations in dissolved nutrients and particulate matter at the mouth of semiclosed Keunso Bay were investigated over four seasons. The role of the bay, whether it acted as a sink or a source, was element-specific and seasonally dependent. Dissolved inorganic nitrogen was imported in spring, summer, and winter due to active denitrification throughout the year and was exported offshore in autumn. For dissolved inorganic phosphorus, the bay served as a sink in spring and winter and as a source in summer and autumn, possibly in association with the redox potential of surface sediments. Similarly, dissolved silicate was imported in spring when a spring bloom occurred, but the bay was a silicate source in summer and autumn. Suspended particulate matter flux also varied seasonally, with tendencies of summer export and winter import, possibly controlled by meteorological conditions and tidal cycle. Particulate organic carbon was exported offshore in summer but imported in winter.

Simulating waves nearshore (SWAN) and steady state wave (STWAVE) nearshore wave transformation models were applied to Long Island, New York, coastal waters to investigate regions of wave focusing and their relationship to offshore shelf and shoal zone morphology. Model simulations extended from 1 February 1999 through 28 February 1999, and encompassed five wave events in which measured significant wave heights exceeded 1.5 m. For many of the storm events, wave energy along the coast was concentrated at Montauk, Westhampton, central Fire Island, Jones Island, and Long Beach. The focusing and structure of wave energy at Westhampton appears to be related to infragravity wave influenced morphology between Shinnecock and Moriches inlets. Wave energy concentration along central Fire Island was the result of shoaling and refraction around a submerged terrace offshore of Watch Hill. In addition the investigation illustrates the benefit of using multiple models to compute wave transformation processes.

Recent studies have employed a new device to measure beach “surface” moisture content, the Delta-T Theta probe. A key weakness of the device for this application is that the sensor length (6.0 cm) exceeds the desirable depth for “surface” measurements in the context of coastal-aeolian processes. This study investigated the reliability of the Delta-T Theta probe when modified to restrict measurement depths to 0.5–1.5 cm. Field investigations were conducted at two beaches in Texas and North Carolina to allow assessment of the influence of different sediment sizes. Results demonstrated that sensor output becomes less sensitive as the sensor length is decreased. However, R² values reveal very strong relationships between probe output and laboratory-measured moisture content, with virtually all sampling runs exceeding 0.90. Further, although the standard error approximately doubled (from ±1% to ±2%) for the modified versions of the probe, the error remained within the accuracy ranges reported in the literature and did not appear to consistently increase as the sensor length was shortened. Grain size was found to have no consistent influence on sensor performance. Comparisons of multiple runs and multiple probes indicated that it is possible to achieve high levels of repeatability both between runs and between probes, but several instances of significant departures were identified that suggest caution with this application and that other environmental parameters may influence results.

The Casuarina spp. are invasive plants in Florida that threaten biological diversity and beach integrity of coastal habitats. The trees include three species and their hybrids that aggressively invade riverine and coastal areas. Of the three species, C. equisetifolia and C. glauca are highly salt tolerant and widespread in coastal areas. The third species, C. cunninghamiana, invades riverine habitats. These species pose dangers to both the environment and public safety. The environmental damage includes interfering with nesting by endangered sea turtles, American crocodiles, and the rare swallow-tailed kite. Additionally, allelochemical leachates reduce germination and establishment of native vegetation. Casuarina-infested beaches are more prone to sand loss and erosion. Moreover, with shallow roots and tall canopies, they are among the first trees to fall in high winds and as such restrict evacuation efforts during hurricanes. Control of these species is mostly with herbicides, requiring repeated applications and monitoring. One of the most cost-effective means of controlling these invasive species would be with classical biological control. Australian surveys for potential biological control agents began in 2004, resulting in the discovery of several promising candidates. These include seed-feeding torymid wasps, defoliating caterpillars and weevils, leaf tip gall-formers from cecidomyiid midges, and sap-feeding psyllids. Continued work is needed to determine the suitability of these species for biological control. Despite conflicts of interest expressed by some homeowners and the agricultural industry who value the trees for shade and windbreaks, there are good prospects for safe and effective biological control of these invasive species.

High biogenic productivity, strong tidal currents, shoal topography, and short transport distances combine to favor shell-bed formation along the lower flanks of a cape-associated shoal off Herod Point on Long Island, New York. This shell bed has a densely packed, clast-supported fabric composed largely of undegraded surf clam (Spisula solidissima) valves. It is widest along the central part of the western flank of the shoal where topographic gradients are steep and a stronger flood tide results in residual flow. The bed is narrower and thinner toward the landward margins where currents are too weak to transport larger valves and topographic gradients are gentle, limiting bed-load transport mechanisms by which the shells are concentrated.

Reconnaissance mapping off Roanoke Point suggests that shell beds are also present at the other cape-associated shoals off northeastern Long Island, where relatively similar geomorphic and oceanographic conditions exist. These shell beds are important to the Long Island Sound ecosystem because they provide complex benthic habitats of rough and hard substrates at the boundary between the muddy basin floor and mobile sand of the shoals.

Some areas of the Texas coast along the Gulf of Mexico are stabilized by beach nourishment or artificial protections, but the northeast Texas coast has been damaged and changed by short- and long-period erosion. The berm or dune that can act as protection from wave activities rarely exists, and mild, sloping beaches increase the potential of erosion in the study area. The upper Texas coast was monitored by Texas A&M University between 1999 and 2005. The measured beach profiles showed the morphological short- and long-period changes by overwash, and critical erosion was observed, especially by the landfall of hurricane Rita in 2005. The suspected causes of severe erosion were analyzed by comparing dune heights and beach widths, and it was found that overwash was one of the major factors causing erosion of the shoreline in the area. When storms made landfall in neighboring regions, such as southern Texas, Louisiana, Mississippi, and Alabama, overwash by long-period waves of remote storms was observed during the beach surveys. Overwash by remote storms could not be ignored, and it was an important contributor to continued beach erosion in the study area. Erosion caused by direct landfall of storms had significant effects on long-period erosion as well.

Sandy coastal sediments in similar wave-exposure conditions in southeastern New Zealand supported different macrofaunal communities in an area with steeply sloped bathymetry compared with an adjacent area with a shallower slope and, therefore, a more wave-dissipating profile. Assemblages were sampled in autumn and spring along three shore-normal transects (6–30 m water depths) in two areas separated by a small headland. There was no sediment texture stratification in surficial sediments and no seasonal variability in sediment texture. Macrofaunal abundance and taxon richness were higher in both areas in spring. Taxon richness generally increased with depth in both communities. Abundance increased with depth at the more reflective site but decreased with depth at the more dissipative site until a possible autecological point was reached, whereafter both abundance and richness continued to increase with depth and community composition merged into a typical shelf community. This merge point supports the notion of a Wave Exclusion Hypothesis (WEH), a shallow subtidal analogue to the Swash Exclusion Hypothesis (SEH) developed for sandy beach processes, where turbulence and sediment instability selectively exclude macroinvertebrates. Macrofaunal communities in the more reflective area were probably constrained by abiotic factors as suggested by morphological traits of dominant taxa. Communities have largely persisted since the 1960s and 1980s. Variability within such a small spatial scale suggests that coastal management decisions should consider the special nature of nearshore environments as a distinct marine habitat where sediment instability may shape communities through different processes than those present in sheltered inlets or deeper shelf environments.

This paper describes the development, behaviour, and application of a mesoscale numerical geomorphological model of eroding soft rock and beach shores. The model, SCAPE (Soft-Cliff and Platform Erosion), describes coastal processes and engineering interventions and is a suitable tool for testing management strategies. The mesoscale capability of SCAPE arises because it includes a broad system: its principal modules describe wave transformation, platform erosion, and a (one-line) beach. Feedback within and between the modules regulates their behaviour, brings long-term (dynamic) stability, and allows quantified representation of qualitatively different shore behaviours. SCAPE is demonstrated through the construction of a model of more than 30 km of the North Norfolk coast. A precalibration initialisation phase is required to allow dynamic equilibrium to emerge. Once initialised, calibrated, and validated against an 87-year record, the model is used to explore the development of the North Norfolk coast from 2003 to 2053 under six management scenarios. The model is also used to demonstrate the losses and benefits of erosion under these scenarios and to reveal two qualitatively different modes of behaviour, termed rock strength limited erosion and sediment transport limited erosion. Some generic implications of these different modes are discussed.

Recently, plant growth–promoting endophytic fungi with gibberellins-producing ability were isolated from the roots of coastal sand dune plants. Carex kobomugi Ohwi in coastal sand dunes was treated with the supernatant solution of Penicillium citrinum KACC43900 isolated from Ixeris repens (L.) A. Gray. After treatment, the length of leaf blades, photosynthesis, chlorophyll fluorescence, and soil respiration were measured in the field. The contents of chlorophyll and carotenoid were determined with leaf blades selected for measurement of chlorophyll fluorescence. Fungal culture filtrate (FCF) increased leaf blade length, the contents of chlorophyll a (Chl a) and chlorophyll b (Chl b), total chlorophyll (total Chl [a b]), and carotenoid in leaf blades of C. kobomugi. FCF also increased net photosynthetic rate (A), transpiration rate (E), carboxylation efficiency (A/Ci), and water-use efficiency (A/E). However, the ratio of variable fluorescence to maximal fluorescence (Fv/Fm) did not show significant difference between control and FCF-treated plants. Soil respiration rates were higher in the site treated with FCF than the control. Although growth response and physiological characteristics of C. kobomugi were different according to the treatment methods of FCF, injection or spray treatment, plant growth of C. kobomugi was increased with FCF treatment.

The evidence from sedimentary structures and the stratigraphic and biostratinomic context of shell layers are used here to describe how shell beds are formed within a sedimentary sand wave. Shell beds in the Pliocene San Nicolás Formation, within the Baja California Central Domain, were accumulated through the physical processes of gravity induced flow currents. The hydraulic regime and sedimentary differences between the up-current slope and the leeward slope part of the sand wave can be explained by flow stratification. The taphonomic differences between the fossil concentrations of the bottom and the upper layers in the leeward slope are a result of a change in the current dynamics for the basin. The leeward slope side of the sand wave represents episodic, short-term, dynamic bypassing in gravity-induced, low-flow current beds creating shell beds.

More informed coastal restoration decisions have become increasingly important given limited resources available for restoration projects and the increasing magnitude of marsh degradation and loss across the Gulf Coast. This research investigated the feasibility and benefits of integrating geospatial technology with the traditional ecological knowledge (TEK) of an indigenous Louisiana coastal population to assess the impacts of current and historical ecosystem change on community viability. The primary goal was to provide coastal resource managers with a decision-support tool that allows for a more comprehensive method of assessing localized ecological change in the Gulf Coast region, which can also benefit human community sustainability. Using remote sensing (RS) and geographic information systems (GIS) mapping products, integrated with a coastal community's TEK to achieve this goal, the research team determined a method for producing vulnerability/sustainability mapping products for an ecosystem-dependent livelihood base of a coastal population based on information derived from RS imagery prioritized with TEK. This study also demonstrates how such an approach can engage affected community residents who are interested in determining and addressing the causes and mitigating the decline of marsh habitat.

Historical image data sets of the study area were acquired to understand evolution of land change to current conditions and project future vulnerability. Image-processing procedures were developed and applied to produce maps that detail land change in the study area at time intervals from 1968 to 2009. This information was combined in a GIS with acquired TEK and scientific data sets relating to marsh vegetation health and vulnerability characteristics to produce mapping products that provide new information for use in the coastal restoration decision-making process. This information includes: (1) marsh areas that are most vulnerable; and (2) the areas that are most significant to community sustainability.

A three-dimensional hydrodynamic model was successfully calibrated and validated for Saltsjö Bay, located in the inner Stockholm archipelago. The work aims to obtain a scientific understanding of specific hydrodynamic characteristics of the bay. The focus is on the influence of the freshwater inflow on the hydrodynamic characteristics of the bay, which shares common features with other relatively small bays and estuaries. The model was used for investigating the flow structure, stratification, exchange process, flushing time, and oxygen content. The predicted water levels, temperature, salinity, and dissolved oxygen (DO) profiles were in good agreement with the measurements. The flow structure in the bay is characterised by the existence of large secondary flow regions and multilayer flows. The principal cause of the large secondary flow regions is the interaction of prevailing two-layer flows that have opposite directions. The stratification can be characterised by two long winter and summer stratification periods and two short overturn periods. In the absence of the freshwater, the two-layer flow changed to a three-layer flow but the flow stratification remained unaltered. The flushing time in Saltsjö Bay (2–29 days) is similar to that found in smaller water bodies. The flushing time increased to 40 days when the freshwater inflows were removed from the model boundaries. The period from 1 September to 1 November is characterised by bottom oxygen deficiency when the DO concentrations fall below 5 mg/L. At the open boundary, 3% to 25% of the total volume of the bay is exchanged daily. The work should be of interest and relevant to other bays of comparable size that have similar hydrodynamic characteristics and are subject to freshwater inflows.

Distributions of phytoplankton density and their relationships to physicochemical variables were investigated using multivariate analyses, based on data collected every two months from a tropical, inland, freshwater estuary in southern Thailand between June 2005 and December 2007. Results indicated 74 genera of phytoplankton in the samples. More than 75% of the genera were diatoms (30 genera; 40.5%) and chlorophytes (29 genera; 39.2%), and 20% were cyanobacteria (6 genera; 8.1%) and dinoflagellates (6 genera; 8.1%). Variations in phytoplankton density largely resulted from salinity and turbidity, which varied seasonally and geographically. Chlorophytes, cyanobacteria, and euglenophytes were the most common groups in the turbid freshwater habitat, whereas diatoms and dinoflagellates dominated along the salinity gradient of the clear estuarine environment. Our results suggest that the Na Thap River has been regulated mainly by the natural phenomena of marine and riverine influences, even though the river is situated on agricultural, aquacultural, and industrial land. Continued observations of phytoplankton density and composition are needed, emphasizing any unusual increases in density and/or the unexpected presence of harmful species. The long-term trends of phytoplankton provide an indication of the change in the trophic status of the basin, as well as a foundation for further studies of the distributions of upper-level aquatic species in freshwater estuarine ecosystems.

Invasion by alien plants has negative effects on coastal dunes. Monitoring local spread of invasive species depends on long-term data with sufficient spatial resolution. Bayesian state-space models are a new method for monitoring invasive plants based on unbalanced permanent-plot data. The method allows separation of process and sampling variance, thus enabling ecological predictions with a known degree of uncertainty. The method is applied for the invasive shrub Rosa rugosa (Japanese rose) in Danish fixed dunes. The probability of observing R. rugosa increased significantly from 0.18 to 0.28 during the period 2004–2007. The species was found in all Danish coastal regions, albeit slightly less common in northern Denmark. We discuss the advantages and limitations of using Bayesian state-space models for monitoring and predicting plant invasions using presence–absence data.

A low-cost hydrographic kayak surveying system was developed and is described here. The kayak survey system is an extremely flexible surveying system; it can be easily deployed in the nearshore, small lakes, and in other small bodies of water where engine-equipped vessels are prohibited. The cost and complexity of the system are minimized by using a low-cost L1 handheld global positioning system (GPS) system, a smart 200 kHz echosounder that outputs a serial depth string, and a simple off-the-shelf serial data acquisition system. The vertical and horizontal errors of the handheld GPS system are evaluated with an inexpensive external L1 patch antenna and a more expensive, nonpatch L1 antenna, resulting in vertical root-mean-square errors of 11 and 2.5 cm, respectively. In addition, bathymetric measurements at Bethany Beach, Delaware, were obtained using the kayak surveying system and compared to a wading and boat survey yielding a root-mean-square error of 17 cm. The kayak surveying system provides an easily constructed, environmentally friendly, low-cost surveying alternative to conventional and personal water craft surveying systems.