Beach Exposure Research Articles

Habitat type and beach exposure shape fish assemblages in the surf zones of ocean beaches

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 570:203-211 (2017) - DOI: https://doi.org/10.3354/meps12115 Habitat type and beach exposure shape fish assemblages in the surf zones of ocean beaches Hayden P. Borland1, Thomas A. Schlacher1, Ben L. Gilby1, Rod M. Connolly2, Nicholas A. Yabsley1, Andrew D. Olds1,* 1School of Science and Engineering, University of the Sunshine Coast, Maroochydore, QLD 4558, Australia 2Australian Rivers Institute-Coasts & Estuaries, and School of Environment, Griffith University, Gold Coast, QLD 4222, Australia *Corresponding author: aolds@usc.edu.au ABSTRACT: The surf zones of ocean beaches are prime fishing sites and provide habitat for a diversity of fish species. The spatial composition of seascapes shapes fish abundance and diversity in most coastal ecosystems, but it remains untested whether seascape effects operate on ocean beaches. This study used the surf zones of sandy beaches in eastern Australia as a model system to contrast fish assemblages between the 2 main surf habitats (nearshore troughs and offshore bars), and test how habitat partitioning changes with beach exposure, wave conditions, seascape connectivity (i.e. proximity to estuaries and rocky headlands) and tide. Fish were sampled with baited remote underwater video stations from the surf zones of 18 sandy beaches in southern Queensland and northern New South Wales. Habitat type and beach exposure combined to shape fish abundance and diversity in the surf. Fish assemblages always differed between nearshore trough and offshore bar habitats; beach exposure was also important to surf fishes but did not alter the priority effects of habitat partitioning. Beach exposure is an important predictor of faunal assemblages on ocean beaches and is often used as a surrogate in conservation planning. Our results show, however, that surf zones are not single uniform spatial units but are composed of topographically and hydrodynamically distinct habitats that support correspondingly distinct fish assemblages. Because fishing effort also differs between surf habitats, fisheries management and spatial conservation planning need to reflect these spatial nuances in the surf zones of ocean beaches. KEY WORDS: Surf zone · Fish · Habitat · Exposure · Ocean beach · Coastal conservation planning Full text in pdf format PreviousNextCite this article as: Borland HP, Schlacher TA, Gilby BL, Connolly RM, Yabsley NA, Olds AD (2017) Habitat type and beach exposure shape fish assemblages in the surf zones of ocean beaches. Mar Ecol Prog Ser 570:203-211. https://doi.org/10.3354/meps12115 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 570. Online publication date: April 27, 2017 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2017 Inter-Research.

Structure and Corrosion Performance of a Non-Chromium Process (NCP) Zr/Zn Pretreatment Conversion Coating on Aluminum Alloys

We report on the physicochemical properties and anti-corrosion performance of a non-chromated Zr/Zn conversion coating (NCP) on AA2024-T3. The immersion coating was formed on polished, degreased and deoxidized specimens. Electrochemical methods were used to assess the corrosion inhibition provided by the coating in laboratory tests. The results were compared with environmental exposure tests to assess the stand-alone corrosion protection. Coated AA6061-T6 and 7075-T6 specimens were also used in the environmental tests. Electrochemical testing in naturally-aerated 0.5 M Na2SO4 + 0.1% NaCl revealed that the NCP coating shifted Ecorr positive by about 250 mV, suppressed anodic more than cathodic current around Ecorr by at least a factor of 10x and shifted Epit more noble. The coating functions more as an anodic inhibitor through barrier layer protection. The coating provided excellent corrosion protection to all three alloys during a 14-day full immersion test in 0.5 M Na2SO4 + 0.1% NaCl. However during 14-day neutral salt spray and thin-layer mist tests, NCP failed to provide much stand-alone corrosion protection to the aluminum alloys and the anti-corrosion properties were found to be inferior to TCP conversion coatings of comparable thickness. A 7-day beach exposure revealed the NCP coating also provides little resistance to galvanic corrosion on the aluminum alloys as compared to TCP coatings. The results demonstrate that laboratory evaluation of the anti-corrosion properties of non-chromated conversion coatings does not always reflect coating performance during accelerated degradation or environmental exposure. The inferior anti-corrosion behavior of NCP, as compared to TCP, is due to (i) inherent defect density of the former (i.e., reduced throwing power) and (ii) the absence of Cr(III) species.

Sandy beach ridges from Xingkai Lake (NE Asia): Timing and response to palaeoclimate

Abstract Lake beach ridges and their sediments have been investigated as palaeoenvironmental records. Robust chronology is crucial to utilize this archive for palaeoenvironmental reconstruction and interpretation. This study investigates the optically stimulated luminescence (OSL) dating of quartz in two beach ridges of aeolian origin from Xingkai Lake (NE Asia). The applicability of the selected measurement procedure is validated by a set of internal tests on luminescence characteristics such as preheat plateau test and dose recovery test, and the reliability of the resulting 24 OSL ages are also confirmed by agreement with four 14C ages as well as two K-feldspar luminescence dates. The constructed chronologies are thought to be robust in the stratigraphic and geomorphologic context. The two aeolian beach ridges (B1 and B2) are dated to ∼32–15 ka and ∼1.2–0.5 ka, respectively, which are interpreted as two distinct periods of lake lowstand that could have caused beach exposure and provided a more extended sand source for foredune formation around Xingkai Lake. These two lowstands could be correlated to the dry/cold regional climate including the time span from late MIS3 to late glacial and the most recent one at the late Holocene.

Sedimentological evidence for the Late Holocene sea level change at the Enjefa Beach exposures of Kuwait, NW Arabian Gulf

The mid-late Holocene drop in relative sea level has resulted in the deposition and progradation of coastal facies along the Enjefa Beach in Kuwait, NW Arabian Gulf. These coastal facies display various depositional subenvironments, including landward foreshore beach, tidal channel, shallow tidal channel, and coastal sand flat. The foreshore beach facies consist of dominantly planar laminated beds. Main tidal channel subenvironments are interpreted for the trough cross-bedded facies. The shallow tidal channel deposits are composed of variable oriented planar wedge-shaped and ripple cross-bedded facies. The coastal sand flat deposits consist of extensively burrowed beds with a large network of Ophiomorpha burrows. These exposures are overlain by the recent continental deposits of rubbles and artificial infill. The mere exposed occurrence of these rocks as well as the above facies stacking pattern reflects progradation as a result of relative drop in sea level. Based on the carbon dating of these sediments, the last phase of the relative sea level drop likely occurred around 1,800 years ago. Neotectonics of local structuring, due to the regional northeastward movement of the Arabian Plate under the Zagros Fold Belt, might have a role in this sea receding

Population biology of the gastropod Olivella minuta (Gastropoda, Olividae) on two sheltered beaches in southeastern Brazil

The structure, dynamics and production of two populations of the olivid gastropod Olivella minuta were analyzed through monthly sampling from November 2009 through October 2011 on two sandy beaches, Pernambuco (very sheltered) and Barequeçaba (sheltered) in São Paulo state (23°48'S), southeastern Brazil. On both beaches, samples were taken along five transects established perpendicular to the waterline. Parameters of the von Bertalanffy growth function were estimated for both populations from monthly length-frequency distributions. The production and turnover ratios were determined using the mass-specific growth rate method. The population on the less-sheltered Barequeçaba Beach was less abundant (120.02 ± 22.60 ind m−1) than on Pernambuco Beach (3295.30 ± 504.86 ind m−1 (±SE)), which we attribute to the greater environmental stability of the latter. Conversely, the mean length, size of the largest individual, and body mass were higher at Barequeçaba than at Pernambuco. The significant differences in the growth of individuals and the mortality rate (Z) between the beaches suggest that density-dependent processes were operating at Pernambuco Beach. The production and P/B ratio at Pernambuco (12.12 g AFDM m−1 year−1 and 1.91 year−1) were higher than at Barequeçaba (0.82 g AFDM m−1 year−1 and 1.06 year−1). The difference in production can be attributed to the higher abundance on Pernambuco, while the higher P/B ratio resulted from the scarcity of smaller individuals in the intertidal zone of Barequeçaba. The P/B ratio estimated for the Pernambuco population is the highest found so far for sandy-beach gastropods. This study reinforces the theory that biological interactions are important regulators of sheltered sandy-beach populations. Future studies with multi-beach sampling are needed to better understand the life-history variations of O. minuta along gradients of degree of exposure of sandy beaches.

Galvanic Test Panels for Accelerated Corrosion Testing of Coated Al Alloys: Part 1—Concept

A test sample incorporating a coated and scribed Al alloy panel and uncoated through-hole fasteners was designed to provide accelerated response during atmospheric corrosion testing in the field or in laboratory chambers. Protective coatings that would take many months to show signs of degradation on normal scribed samples with no galvanic connection exhibited corrosion in much shorter times when uncoated Ti alloy or stainless steel fasteners were used, particularly in conjunction with scribes through the coating. The results after three weeks of exposure to ASTM B117 correlated well with long-term beach exposure, allowing rapid ranking of different coating systems. Of the fastener materials studied, visual observation indicated that the worst attack occurred near Type 316 (UNS S31600) stainless steel (SS316) fasteners even though Ti-6Al-4V fasteners are more noble. The volume of AA2024-T3 (UNS A92024) lost during the exposure, as determined by an optical profilometer, was also largest for samples with SS316 fasteners. Scanning Kelvin probe measurements across the scribes on one of the coating systems showed that, after exposure in an ASTM B117 salt fog chamber, the potential was lowest for scribes next to SS316 fasteners. The difference between SS316 and Ti-6Al-4V was explained by the available cathodic current, which was measured in chloride solution.

Brazilian sandy beach macrofauna production: a review

The state of the art of the studies on the production of Brazilian sandy beach macrofauna was analyzed on the basis of the data available in the literature. For this purpose, the representativeness of the production dataset was examined by latitudinal distribution, degree of exposure and morphodynamic state of beaches, taxonomic groups, and methods employed. A descriptive analysis was, further, made to investigate the trends in production of the more representative taxonomic groups and species of sandy beach macrofauna. A total of 69 macrofauna annual production estimates were obtained for 38 populations from 25 studies carried out between 22º56'S and 32º20'S. Production estimates were restricted to populations on beaches located on the southern and southeastern Brazilian coast. Most of the populations in the dataset inhabit exposed dissipative sandy beaches and are mainly represented by mollusks and crustaceans, with a smaller number of polychaetes. The trends in production among taxonomic groups follow a similar pattern to that observed on beaches throughout the world, with high values for bivalves and decapods. The high turnover rate (P/B ratio) of the latter was due to the presence of several populations of the mole crab Emerita brasiliensis, which can attain high values of productivity, in the dataset. Most of the studies focus on the comparison of production and, especially, of P/B ratio according to life history traits in populations of the same species/taxonomic group. Despite the importance of life history-production studies, other approaches, such as the effect of man-induce disturbances on the macrofauna, should be undertaken in these threatened environments.

Morphology and composition of beach-cast Posidonia oceanica litter on beaches with different exposures

Posidonia oceanica seagrass litter is commonly found along sandy shores in the Mediterranean region, forming structures called banquettes, which are often removed in order to allow the beach to be used for tourism. This paper evaluates the relationship between the morphology and composition of banquettes and beach exposure to dominant waves. A Real Time Kinematic Differential Global Positioning System was used to evaluate the variability of banquettes and beach morphology over a period of 1year. Banquette samples, collected at two different levels of the beach profile (i.e. foreshore and backshore), were used to evaluate the contribution of leaves, rhizomes and sediments to the total weight. Banquettes showed a higher volume, thickness and cross-shore length on exposed beaches, whereas narrower litter deposits were found on the sheltered beach. On exposed beaches, banquettes were deposited in beach zones characterized by changes in elevation. These changes in elevation were mainly due to the deposition and erosion of sediments and secondly to the deposition and or erosion of leaf litter. On sheltered beaches, the variability in beach morphology was low and was restricted to areas where the banquettes were located. The leaf/sediment ratio changed along the cross-shore profile. On the backshore, banquettes were a mixture of sediments and leaves, whereas leaves were the main component on the foreshore, independently of the beach exposure. The processes which control the morphodynamics in the swash zone could explain the variability of banquette composition along the cross-shore profile. Finally, this study highlighted that Posidonia oceanica seagrass litter plays an important role in the geomorphology of the beachface and its removal can have a harmful impact on the beaches.

Daily measures of microbes and human health at a non-point source marine beach.

Studies evaluating the relationship between microbes and human health at non-point source beaches are necessary for establishing criteria which would protect public health while minimizing economic burdens. The objective of this study was to evaluate water quality and daily cumulative health effects (gastrointestinal, skin, and respiratory illnesses) for bathers at a non-point source subtropical marine recreational beach in order to better understand the inter-relationships between these factors and hence improve monitoring and pollution prevention techniques. Daily composite samples were collected, during the Oceans and Human Health Beach Exposure Assessment and Characterization Health Epidemiologic Study conducted in Miami (Florida, USA) at a non-point source beach, and analyzed for several pathogens, microbial source tracking markers, indicator microbes, and environmental parameters. Analysis demonstrated that rainfall and tide were more influential, when compared to other environmental factors and source tracking markers, in determining the presence of both indicator microbes and pathogens. Antecedent rainfall and F+ coliphage detection in water should be further assessed to confirm their possible association with skin and gastrointestinal (GI) illness outcomes, respectively. The results of this research illustrate the potential complexity of beach systems characterized by non-point sources, and how more novel and comprehensive approaches are needed to assess beach water quality for the purpose of protecting bather health.

Aerosolized red tide toxins (brevetoxins) and asthma: Continued health effects after 1 h beach exposure

Blooms of the toxic dinoflagellate, Karenia brevis, produce potent neurotoxins in marine aerosols. Recent studies have demonstrated acute changes in both symptoms and pulmonary function in asthmatics after only 1 h of beach exposure to these aerosols. This study investigated if there were latent and/or sustained effects in asthmatics in the days following the initial beach exposure during periods with and without an active Florida red tide. Symptom data and spirometry data were collected before and after 1 h of beach exposure. Subjects kept daily symptom diaries and measured their peak flow each morning for 5 days following beach exposure. During non-exposure periods, there were no significant changes in symptoms or pulmonary function either acutely or over 5 days of follow-up. After the beach exposure during an active Florida red tide, subjects had elevated mean symptoms which did not return to the pre-exposure baseline for at least 4 days. The peak flow measurements decreased after the initial beach exposure, decreased further within 24 h, and continued to be suppressed even after 5 days. Asthmatics may continue to have increased symptoms and delayed respiratory function suppression for several days after 1 h of exposure to the Florida red tide toxin aerosols.

Ecology of megabenthic bivalve communities from sandy beaches on the south coast of Portugal

Ecological aspects of 75 megabenthic bivalve species found on the south coast of Portugal (from Vila Real to Sagres) were studied based on the information provided by seasonal bivalve surveys from 2000 to 2007 (8600 hauls, simultaneously using a razor shell dredge and a clam dredge). Of the 75 species identified, 36 occurred less than 30 times, and thus were considered rare in the area. The remaining 39 bivalves were analysed according to their occurrence, bathymetric distribution, geographic preferences, seasonal preferences, burying-depth, beach exposure and river mouth proximity. All species belonging to the Pharidae and Solenidae families (razor shells) and most Tellinidae were significantly more frequent in the razor shell dredge (indicating deeper burying in the sediment), whilst the families Cardiidae and Donacidae were significantly more frequent in the clam dredge (indicating that these species are probably closer to the sediment surface). As for the season, most bivalve species occurred similarly in both seasons (19 sp; 49%), but a large proportion were more abundant during the autumn surveys (17 sp., 44%), whereas only three species were commoner during the spring surveys. Most species belonging to the families Cardiidae and Mactridae were commoner in the autumn surveys. The spatial distribution differed between species and cluster analysis identified four communities with greater geographic affinity. Species belonging to the family Cardiidae were preferably found in the western part (WB) and the eastern part (S) of the study area, whereas the families Donacidae, Mactridae and Tellinidae occurred mainly in the central area (EB) and the eastern (S) coastal sectors. Overall, shallower species (modal depth at 3-6 m) showed greater occurrences and abundances than the deeper ones, and the depth pattern observed did not change between seasons. Donacidae and Mactridae (except Mactra glauca ) were represented essentially by shallow species, whereas Cardiidae (except Acanthocardia tuberculata and Cerastoderma edule ) included mostly species occurring in deeper waters. Bathymetric sequence of species distribution within some families was observed.

Inland transport of aerosolized Florida red tide toxins

Florida red tides, an annual event off the west coast of Florida, are caused by the toxic dinoflagellate, Karenia brevis. K. brevis produces a suite of potent neurotoxins, brevetoxins, which kill fish, sea birds, and marine mammals, as well as sickening humans who consume contaminated shellfish. These toxins become part of the marine aerosol, and can also be inhaled by humans and other animals. Recent studies have demonstrated a significant increase in symptoms and decrease in lung function in asthmatics after only one hour of beach exposure during an onshore Florida red tide bloom. This study constructed a transect line placing high volume air samplers to measure brevetoxins at sites beginning at the beach, moving approximately 6.4 km inland. One non-exposure and 2 exposure studies, each of 5 days duration, were conducted. No toxins were measured in the air during the non-exposure period. During the 2 exposure periods, the amount of brevetoxins varied considerably by site and by date. Nevertheless, brevetoxins were measured at least 4.2 km from the beach and/or 1.6 km from the coastal shoreline. Therefore, populations sensitive to brevetoxins (such as asthmatics) need to know that leaving the beach may not discontinue their environmental exposure to brevetoxin aerosols.

Distribution and abundance of meiofauna in intertidal sand substrata around Iceland

Iceland is situated in an important subarctic transition area where complex oceanographic dynamics occur. The intertidal, subtidal, and deep-sea faunal communities of Iceland are being intensively studied, as a critical resource for continued sustainability of fisheries and the preservation of northern littoral ecosystems. However, the meiofaunal communities and the environmental factors affecting them are still relatively poorly known. The meiobenthic metazoan community was studied with core sampling in 23 sandy beaches along the intertidal zone of the Iceland coast in a campaign developed in September 2003. Small-scale variation in meiofauna composition (major taxa) was explored and related to biotic and abiotic factors at different scales, such as beach exposure, granulometry, and organic matter content. Differences in meiofaunal community structure at a low taxonomic resolution appeared among beaches located within wide biogeographical zones of hydrobiological significance (NE and SW Shelf regions) and exposure degrees. Seventeen major taxa were recorded. In contrast with more local and taxon-focused studies, oligochaetes were the dominant group all around Iceland, followed by nematodes, turbellarians, gastrotrichs, and copepods (mainly harpacticoids). Acari, ascidians, bivalves, cnidarians, collembolans, gastropods, isopods, kinorhynchs, insects, nemerteans, ostracods, and polychaetes were relatively scarce groups, together being less than 1.6% of the meiofauna. There was a large variation in meiofaunal abundance between sites. Maximum abundances (>500 ind. cm−2) were found in Sauđarkrokur, Hraunhafnartangi, and Skalaness, whereas minimum abundances (<40 ind. cm−2) were recorded in Magnavik, Jokulsarlon (glacier beach site), Vikurnupur, Breidalsvik, and Stokknes. We did not find a clear pattern in overall meiofaunal abundance regarding the degree of exposure of beaches. Oligochaetes, nematodes, and copepods were relatively more abundant in sheltered beaches, whereas turbellarians and gastrotrichs tended to be more abundant in exposed beaches. The best correlates of meiofaunal composition and abundance within beaches were the proportion of gravels and the content of utilizable organic matter in the sediment. We should consider factors operating at wider scales (importantly beach exposure and overall situation in the complex oceanographical context of Iceland) to find a pattern in the local structure of intertidal meiofaunal assemblages.

Marine and Coastal Science: Red Tide Chokehold

The waters of the Gulf of Mexico regularly erupt with algal blooms known as Florida red tides, caused by overgrowth of the dinoflagellate Karenia brevis. These particular red tides release potent neurotoxins called brevetoxins. Several recently published papers help to clarify the health effects of shoreline brevetoxin aerosols, particularly for asthmatics and pregnant women. The papers were published by a team of researchers from seven institutions and funded by the NIEHS, the CDC, and the Florida Department of Health. People who eat brevetoxin-contaminated bivalves (such as clams and oysters) develop acute gastrointestinal and neurological symptoms. When brevetoxin aerosols blow ashore, people may experience irritated eyes, coughing, and wheezing. Symptoms generally subside in healthy people once they leave the beach or enter air-conditioned buildings. Asthmatics, however, are more vulnerable to red tide aerosols, reports Lora Fleming, an epidemiologist at the University of Miami School of Medicine and Rosenstiel School of Marine and Atmospheric Sciences, with her colleagues in the January 2007 issue of Chest. The team measured aerosol brevetoxin exposures and monitored symptoms in 97 asthmatics who visited Sarasota’s Siesta Beach during two active K. brevis blooms and three lull periods. Lung function was measured by spirometry before and after one-hour beach outings. During blooms, all participants reported an increase in symptoms (especially chest tightness) after beach exposure, and spirometry values uniformly decreased. No differences in symptoms or spirometry values were detected during lulls in K. brevis blooms. People with more severe asthma showed greater changes in pre- and post-beach spirometry values during red tide blooms, compared to those with mild/moderate asthma. Fleming advises sensitive people to avoid beaches when K. brevis is blooming and winds are blowing toward shore. Pregnant women, too, should consider avoiding beaches during K. brevis blooms. Janet Benson, an inhalation toxicologist at the Lovelace Respiratory Research Institute, coordinated the first study ever of placental transfer of brevetoxins, published in the December 2006 issue of Toxicon. Pregnant mice received a radioactive form of brevetox-in-3, a major component of brevetoxin aerosols detected along beaches. The toxin and its by-products were identified in fetuses and uterine and placental tissues 48 hours later, as well as in the stomachs of nursing pups born to brevetoxin-exposed mothers. “The doses given pregnant mice were high and not representative of what humans are exposed to,” says Benson. Still, the results suggest that pregnant or nursing women exposed to brevetoxins may pass them to their fetuses or babies. Animal experiments have shown that brevetoxins localize in the cerebellum, though little was known about how inhaled brevetoxins affect the brain. In the December 2006 issue of Inhalation Toxicology, however, the team reports that when mice inhaled brevetoxin-3 for two days, neuronal damage was observed largely in the posterior cingulated/retrosplenial cortex, but no behavioral changes occurred. The findings add to accumulating evidence that inhaled brevetoxins disperse to several body sites, though coauthor Daniel Baden, director of the Center for Marine Science at the University of North Carolina, Wilmington, says it’s too early to extrapolate to humans. Baden, who has studied brevetoxins since 1973, says Florida red tides are occurring more frequently and often last for months. Although largely confined to the coastline along the Gulf of Mexico, K. brevis can travel as far north as North Carolina. Onshore concentrations of brevetoxin aerosols associated with reported respiratory symptoms range from 0.5 to 108 ng/m3. However, Baden says, “As far as we’re concerned, there is no dose that is low enough to not be of concern.” People have reported experiencing symptoms associated with brevetoxin exposure even when levels of the toxins were so low as to be undetectable by sophisticated monitors. Are changes in global climate adding to the problem of Florida red tides? Scientists are studying whether changing ocean temperatures, currents, and weather patterns associated with climate change may be affecting Florida red tides. “Climate change is a concern, especially with recent blooms lasting longer, but we don’t have hard data yet,” says Barbara Kirkpatrick, manager of the Environmental Health Program at the Mote Marine Laboratory in Sarasota and a coauthor of the Chest paper. Her colleagues at the Mote Marine Laboratory have placed different types of sensors in several locations to monitor Florida red tide blooms and climate conditions. “It’s going to take long-term data sets to make conclusions,” Kirkpatrick says.

Failure of navy coating systems 1: chemical depth profiling of artificially and naturally weathered high-solids aliphatic poly(ester-urethane) military coating systems

A variety of weathering protocols are in use in industry and research laboratories to both replicate and accelerate the effects of weathering on coating systems. This work focuses on the use of two artificial and one natural weathering protocol (QUV, GM9540P, Florida beach exposure) in combination with spatially resolved transmission-mode Fourier transform infrared (FT-IR) spectroscopy for the purpose of chemically depth-profiling highly opaque high solids multi-layer poly(ester-urethane) coatings employed by the U.S. Department of Defense. Samples were prepared via subjection to 6/12-week GM9540P exposure, 7/13/25-week Florida beach exposure, or 6-/18-week QUV protocol. Thin (3 μm) cross-section samples were prepared via microtomy and depth-dependant trends in chemical evolutions were analyzed using transmission-mode micro-FT-IR. Scanning electron/energy-dispersive microscopy (SEM/EDS) was conducted on 10 μm cross-sections and spatial distribution/chemical makeup of inorganic constituents were analyzed. An apparent synergistic relationship between weathering protocols was found. It was theorized that a combination of chemistry and morphology of the inorganic fillers was primarily responsible for greater-than-expected photooxidative modification of the polymeric binder.

Potential Use of Uniola paniculata Rhizome Fragments for Dune Restoration

Abstract Uniola paniculata (sea oats) rhizomes uprooted by hurricanes and deposited as wrack could be salvaged and replanted in dune restoration. To test this unexplored technique, percent tiller emergence was observed for 4 years from U. paniculata rhizomes replanted after submersion in seawater; air exposure of 0, 1, 3, 5, 7, and 11 days; freshwater rinse; and reburial in pots (watered) or on the beach (with or without supplemental water). In addition, U. paniculata rhizomes uprooted by Hurricane Georges were experimentally planted, and effects of soil salinity and moisture on emergence were tested in the greenhouse. Tiller emergence declined with increasing length of air exposure and decreasing size of rhizome. Tiller survival was enhanced by rainfall, rinsing with salt or fresh water during exposure and immediately after planting or supplemental beach watering. Although emergence was not reduced by soil salinity of 1,800 μS/cm, emergence was reduced by soil salinity of 5,800 μS/cm. Across the 4 years of the study tiller emergence from treated rhizomes varied considerably. U. paniculata rhizomes lost bud viability after 3–5 days of beach exposure, unless fresh water from rainfall, wet burlap storage, or watering was applied within 3 days. Bud viability was extended through 11 days when supplied with water. Thus, reburial within 3–11 days after a storm is a viable restoration technique.

Coating evaluation and validation of accelerated test conditions using an in-situ corrosion sensor

An in-situ corrosion sensor was used to obtain electrochemical impedance spectroscopy (EIS) measurements on coated panels under a variety of accelerated laboratory test conditions as well as ambient exposure at a Florida beach. Three studies are reported. The first compared the sensor (EIS) measurements taken in a salt fog chamber to those obtained using a clamp-on cell and the conventional remote electrode/immersion approach. For coatings with minimal edge defects, the two methods gave equivalent results. For coatings with edge defects, the sensor was able to detect the defects provided the surface was wet, as in the salt fog chamber. In contrast, the conventional approach was unable to detect defects unless they were within the confines of the clamp-on cell. In the second case, sensor measurements were used to compare coating degradation during salt fog, a cyclic corrosion test, humidity, and immersion to that occurring at a Florida beach. The cyclic corrosion test showed an excellent correlation with beach exposure while the salt fog and other test showed very little correlation, suggesting that the cyclic test is more valid for discriminating coating performance for seacoast exposure. The sensor also indicated that the test could be short-ened by up to 40% without significantly reducing the validity of the test. In the final example, a series of primers and appliques were evaluated using the cyclic corrosion test. The sensor EIS results allowed a discrimination between the materials sets even though there was little or no visual difference between the specimens.

TEXSONDE '94—RADAR MEASUREMENT OF SURFACE CURRENTS FOR OIL SPILL MODELING

ABSTRACT The SeaSonde 12.5 MHz radar was used to measure surface currents offshore Galveston for a one month period (March 1994). The radar generally performed well when sited with open beach exposure; however, data return was found to vary with wind direction, which led to occasional reductions in the total coverage area. Although useful for input directly to oil spill models, the utility of the radar current data could be improved through assimilation into hydrodynamic flow models.

Environmental Dose Assessment For Low-level Radioactive Effluents Discharged From Tokai Reprocessing Plant

In the normal operation of the Tokai reprocessing plant, low-level radioactive effluents are discharged to the atmosphere and the ocean under rigid control. Radiation exposures to the population around the plant have been estimated for potential pathways with site-specific parameters such as food consumption, concentration factors of marine organisms, and meteorological conditions. External exposures to a radioactive cloud and internal exposures from inhalation and oral intake of radionuclides are evaluated for airborne effluents. External exposures to a contaminated fishing net and fishing boat are considered pathways for fishermen. External exposure to a contaminated beach and internal exposure via oral intake of marine products are evaluated for liquid effluents. Since the plant began operation in 1977, estimated effective dose equivalents for the public have been less than the annual effective dose equivalent limit of 0.1% recommended by the International Commission on Radiological Protection (1977).

Beach rocks of the Central West Coast of India

Along the central west coast of India several beach rock exposures have been observed in the intertidal zone, as well as 2–4 m above the present day high water line. Beach rock has almost the same general composition as the loose beach sand over which it lies. It takes the broad morphology of the intertidal zone of the beach in which it developed and it shows similar internal structures. Most of it is medium to coarse grained but some is fine to medium grained. The constituents are calcite, aragonite, quartz, feldspar, traces of black (heavy) minerals, rock fragments and shells. Carbonate reaches up to 97% (% wt).