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Sample records for beach isopod excirolana

  1. Biogeographic patterns in life history traits of the Pan-American sandy beach isopod Excirolana braziliensis

    NASA Astrophysics Data System (ADS)

    Cardoso, Ricardo S.; Defeo, Omar

    2004-11-01

    Biogeographic patterns in life history traits of the Pan-American sandy beach isopod Excirolana braziliensis were analyzed to determine latitudinal variations along its distribution, from tropical (9°N) to temperate (39°S) sandy beaches in Atlantic and Pacific oceans. Population features exhibited systematic geographical patterns of variation: (1) an increase in individual sizes and growth rates towards temperate beaches, following an inverse relationship with mean water temperature of the surf zone; (2) a shift from almost continuous to seasonal growth from subtropical to temperate Atlantic beaches and a positive relationship between amplitude of intra-annual growth oscillations and temperature range; (3) a linear decrease in life span and an increase in natural mortality from temperate to subtropical beaches; and (4) an increase in the individual mass-at-size (length-mass relationship) from subtropical to temperate beaches. Analyses discriminated by sex were consistent with the patterns illustrated above. Local effects of temperature and beach morphodynamics are discussed. Our results demonstrate that the population dynamics of E. braziliensis is highly plastic over latitudinal gradients, with large-scale variations in temperature and concurrent environmental variables leading to an adjustment of the phenotype-environment relationship.

  2. Reproductive biology of the isopod Excirolana braziliensis at the southern edge of its geographical range

    NASA Astrophysics Data System (ADS)

    Martínez, Gastón; Defeo, Omar

    2006-12-01

    A full analysis of the reproductive biology of the isopod Excirolana braziliensis Richardson 1912 was conducted in a sandy beach of Uruguay, located at the southernmost edge of its distributional range in the Atlantic Ocean. Reproductive and recruitment periods of E. braziliensis were concentrated in austral summer. Females with oostegites appeared in November, whereas total biomass, individual sizes and fecundity of ovigerous females peaked between December and January. These concurrent traits were responsible for the significant peak of juveniles in January. The size at maturity was 9.88 mm. Four embryonic developmental stages were described and identified: mean length linearly increased from stages I to III, whereas dry weight exponentially decreased from stages I to IV. The high reproductive output (0.41-0.58), reported for the first time in this isopod, exceeds the rates documented for other isopods. Reproduction of E. braziliensis at the southern edge of its range is semelparous: females produce one brood during the reproductive season, exhaust their energy reserves during incubation, and probably die at the end of the reproductive season. A macroscale comparison suggests that E. braziliensis at the southern edge of its range counteracts its narrow reproductive period by a short incubation period with larger individual mature female and embryo sizes, higher fecundity and a higher percentage of ovigerous females than in subtropical and tropical populations. These extreme reproductive indicators could be attributed to the internal retention of embryos that assures offspring survival, coupled with a high adaptation capability to environmental variations across its range.

  3. Production of Excirolana armata (Dana, 1853) (Isopoda, Cirolanidae) on an exposed sandy beach in southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Petracco, Marcelo; Cardoso, Ricardo Silva; Turra, Alexander; Corbisier, Thais Navajas

    2012-09-01

    The somatic and gonad productions of the cirolanid isopod Excirolana armata were analyzed by taking monthly samples from December 2003 to November 2005 on Una beach, São Paulo state (24°S), southeastern Brazil. Sampling was performed along three fixed transects established from the base of the foredunes to the waterline. Weight-specific growth rate was used to estimate the E. armata somatic production for 2004 and 2005, separately. The gonad production was estimated based on the monthly reproductive potential (mean number of eggs/embryos per female × monthly abundance of ovigerous females with near-release broods) for 2004. The annual somatic production of E. armata population varied from 15.57 to 17.25 g AFDW m-1 year-1 and the somatic production/biomass ratio ( P s/ B) from 3.55 to 3.14 year-1 for 2004 and 2005, respectively. The P s/ B ratios were higher for males (4.02 and 3.19 year-1 for 2004 and 2005) than for females (3.10 year-1 for both years). The annual gonad production ( P g = 1.07 g AFDW m-1 year-1) contributed about 15 and 6% to the total production ( P s + P g) of females and the population, respectively. The proportion of gonad to somatic production of females ( P g/ P s) increased with individual size (ca 90% in the 7.5 mm size class), and the annual weight-specific gonad production ( P g/ B ratio) was estimated to 0.24 year-1. The high P s/ B ratios estimated for E. armata derive from the fast growth of individuals and show the importance of this population to the energy flow on Una beach ecosystem. However, the low percentage of juveniles verified in this population and in other studies of populations of the genus Excirolana is discussed as an important source of underestimation of P s/ B ratio.

  4. Is Sandy Beach Macrofauna Only Physically Controlled? Role of Substrate and Competition in Isopods

    NASA Astrophysics Data System (ADS)

    Defeo, O.; Brazeiro, A.; de Alava, A.; Riestra, G.

    1997-10-01

    Exposed sandy beaches have been defined as physically stressful environments, so that benthic populations living there are thought to be regulated mainly by physical factors, biological interactions being minimal. However, recent long-term studies indicate that potential intra- and interspecific interactions should also play a role in structuring populations and communities. This paper evaluates the role of sediment characteristics and potential interactions in determining the abundance and distribution patterns of the cirolanid isopods Excirolana armataand Excirolana braziliensisin sandy beaches of Uruguay. Results from concurrent field sampling and laboratory experiments showed that: (1) at a macroscale (between beaches), E. armataoccurred only in beaches with fine sands, whereas E. braziliensiswas observed in both fine and coarse sand beaches, reaching its highest density in the latter; (2) at a mesoscale (within beaches) and in sympatry (fine sands), both cirolanids showed maximum densities at different tidal heights, with E. braziliensisrestricted to the upper beach levels; (3) both isopods showed a clear preference for fine sands, when tested in isolation or combined; (4) survivorship of E. armatawas higher when tested in the preferred sediment under co-occurrence with E. braziliensis, which in turn presented higher survivorship in coarse sand, either in isolation or combined with E. armata; and (5) individual mean length of both species was consistently higher in allopatry, and similar body lengths were observed in sympatric populations. A geographical analysis of the abundance of E. braziliensisalong Pan-American beaches showed that this isopod is most abundant in fine sands; this overall pattern supports conclusions derived from sediment preference experiments, implicating a greater niche breadth than that observed in Uruguayan beaches. It was concluded that E. armatacould be defined as a high substrate-specific species in which intraspecific interactions would be of utmost importance in population regulation. However, distribution patterns of E. braziliensiscould not be explained by a simple animal-sediment relationship, and correlational evidence suggests that it is displaced by E. armatatowards coarse sands and upper beach levels. Thus, potential biotic interactions cannot be discarded as a structuring force in sandy beach communities.

  5. Role of suction in sandy beach habitats and the distributions of three amphipod and isopod species

    NASA Astrophysics Data System (ADS)

    Sassa, Shinji; Yang, Soonbo; Watabe, Yoichi; Kajihara, Naoto; Takada, Yoshitake

    2014-01-01

    Sandy beach ecology has progressed rapidly with the emergence of several theories developed on the basis of understanding of hydrodynamic and morphodynamic processes on sandy beach habitats. However, the possible role of dynamic geophysical processes in the sediments remains poorly understood. The present study aims to explore the role of such geophysical processes in the sediments in forming the habitat environment and how they influence the species distributions. We conducted sets of integrated observations and surveys on intertidal and supratidal geophysical environments and the distributions of three amphipod and isopod species at four exposed sandy beaches located on the Japan Sea coast of Niigata Prefecture, Japan. The field results combined with a series of laboratory soil tests demonstrate that suction governed the variability of habitat environments observed, involving the degree of saturation, density, and hardness of the cross-shore intertidal and supratidal sediments, depending on the severity of the suction-dynamics-induced sediment compaction. While the observed species abundances were consistent with existing theories relating to intertidal and supratidal species, the observed magnitudes of suction were responsible for the distribution limits of the amphipods Haustorioides japonicus and Talorchestia brito and the isopod Excirolana chiltoni manifested consistently throughout the different beaches. The results of controlled laboratory experiments and field tests further revealed three distinctive suction-induced mechanisms, associated with their burrowing and physiology and the stability of the burrows. The novel role of such suction-induced geophysical processes in forming the habitat environment and influencing the species distributions may advance our understanding of sandy beach ecology in intertidal and supratidal zones.

  6. Geographical variation in natural history of the sandy beach isopod Excirolana hirsuticauda Menzies (Cirolanidae) on the Chilean coast

    NASA Astrophysics Data System (ADS)

    Rosales-Hoz, L.; Cundy, A. B.; Bahena-Manjarrez, J. L.

    2003-10-01

    Large scale industrial development has taken place in the Coatzacoalcos river estuary, SE Mexico, over the last 32 years, and the area is now regarded as the most polluted coastal area of Mexico. A series of sediment cores were taken from the lower Coatzacoalcos river and the estuary, and the concentrations of trace elements (Zn, Co, Cu, Cr, Ni, Pb, V), major elements (Al, Si, Mn, Fe, Ti, Ca, Mg, Na, K, P) and organic matter determined. Heavy metal concentration seems to be largely dependant on proximity to industrial areas, with highest metal concentrations (particularly for Zn, Ni and Cu) found at Teapa, the most heavily industrialized site, and lowest values found at Jicaro, upstream of the main industrial areas. At all of the sites examined, heavy metals either show a relatively uniform distribution with depth, or subsurface maxima, which reflect changes in sediment composition. There is little evidence for significant early-diagenetic remobilization at any of the sites studied. 210Pb and 137Cs data at Teapa indicate that the sediments have accreted rapidly and may be vigorously mixed, and so these sediment cores cannot be used to reliably reconstruct temporal changes in pollutant input.

  7. Biotope and biology of Armadillidium album Dollfuss, a terrestrial isopod of sandy beaches, in the SW Netherlands

    NASA Astrophysics Data System (ADS)

    Vader, Wim; De Wolf, Lein

    The supralittoral isopod Armadillidium album Dollfus is common, although patchily distributed, under driftwood on the foreshore of broad sandy beaches on the outer coast of the Delta area in the SW Netherlands. The isopods are very tolerant of immersion in seawater, but are nevertheless confined to a narrow zone just above normal spring tides. A. album is a sexually reproducing isopod, with a single well-defined reproductive period in summer and a lifespan of two years. In spite of its very specialized biotope, the life cycle and reproductive strategy of A. album do not deviate substantially from those of related ubiquitous terrestrial isopods.

  8. Suprabenthic biodiversity of Catalan beaches (NW Mediterranean)

    NASA Astrophysics Data System (ADS)

    Munilla, T.; San Vicente, C.

    2005-03-01

    An analysis of the suprabenthos has been carried out on 13 diverse type beaches in Catalonian coast (NE of Spain). A total of 29 717 specimens, belonging to 145 species and eight different zoological groups (mysids, amphipods, cumaceans, isopods, tanaidaceans, decapods, pycnogonids, and teleostean fishes) were obtained. The suprabenthos of Catalan beaches were characterized by a mean density of 40 ind. m -2, by the abundance of Mysids (75% of the total density) and by the higher diversity of Amphipods (64 species). Five population species were considered as typical of suprabenthic assemblages: Schistomysis assimilis, Mesopodopsis slabberi, Atylus guttatus, Pontocrates altamarinus, and Cumopsis goodsir. Four main types of beaches with different number of suprabenthic species and densities and three main faunistic groups are described and related to environmental physical factors of the analysed beaches (morphodynamics, exposure, etc.). The macrofaunal trend about to that the species richness decrease from dissipative to reflective beaches is confirmed for the suprabenthic communities.

  9. Wolbachia in Neotropical terrestrial isopods.

    PubMed

    Zimmermann, Bianca L; Bouchon, Didier; Almerão, Maurício P; Araujo, Paula B

    2015-04-01

    Despite Wolbachia being widespread among terrestrial isopods, studies on this symbiotic relationship are still incipient in the Neotropical region. The aims of the present study were to investigate the presence and prevalence of Wolbachia in natural populations of terrestrial isopod species in South America, and to analyze the diversity and phylogenetic relationships of Wolbachia strains. A total of 1172 individuals representing 11 families and 35 species were analyzed. We observed distinct evolutionary scenarios according to the geographical origins of the species: strains harbored by most of the introduced species belong to the Oniclade in supergroup B and are identical to those found in their original ecozone (i.e. Palearctic). On the other hand, the strains found in native Neotropical terrestrial isopods showed low prevalence, high diversity and none of them belonged to the Oniclade, although most belonged to supergroup B. The dynamics of infection in Neotropical species seems to be the result of several events of loss and acquisition of the bacteria, which refutes the hypothesis of an ancestral acquisition of Wolbachia in Oniscidea. The presence of strains from supergroups A and F was also detected for the first time in terrestrial isopods, revealing a Wolbachia diversity previously unknown for this group of host. PMID:25764472

  10. Long or short? Investigating the effect of beach length and other environmental parameters on macrofaunal assemblages of Maltese pocket beaches

    NASA Astrophysics Data System (ADS)

    Deidun, A.; Schembri, P. J.

    2008-08-01

    Despite numerous published studies that have evaluated the influence of different physical parameters, including beach slope, sediment organic content and grain size, on beach macrofaunal assemblages, very few studies have investigated the influence of beach length on biotic attributes of the same assemblages. Four beaches on the Maltese Islands were sampled using pitfall traps at night for eight consecutive seasons during 2001-2003. Macrofaunal collections were dominated by arthropods, mostly isopods (especially Tylos europaeus) and tenebrionid beetles (especially Phaleria spp.). The environmental variables of beach slope, exposure to wave action, sediment organic content, mean particle diameter, log beach length, beach width and the beach deposit index (BDI) were regressed against a number of biotic parameters, including log individual abundance, total species, Shannon-Wiener ( H') diversity index value and the psammophilic fraction of the total species collected, whilst BIO-ENV and NMDS were used to identify the physical parameter which could best explain observed biotic patterns. RELATE was used to assess the long-term persistence of macrofaunal assemblages on beaches of different lengths. Results from this study suggest that, whilst the influence of beach length and beach width on individual abundance and total species number is unimportant, these 'beach-area' parameters may affect the taxonomic composition of a beach assemblage, mainly in terms of the psammophilic fraction of assemblages, as well as the permanence of macrofaunal assemblages on a beach. Shorter and narrower beaches were found to be more prone to sporadic and random events of colonisation by euryoecious species. In the absence of human disturbance and mass mortality events, beaches of limited dimensions can still maintain stable macrofaunal assemblages. Individual abundance and total species number could not be related to a single or small suite of physical parameters. The study further highlights the need to include biological interactions, the degree of human disturbance and other variables such as environmental heterogeneity and the connectivity of the individual beaches when assessing inter-beach differences in macrofaunal assemblages.

  11. A hydrodynamically modified, abyssal isopod fauna

    NASA Astrophysics Data System (ADS)

    Thistle, David; Wilson, George D. F.

    1987-01-01

    At the High Energy Benthic Boundary Layer Experiment (HEBBLE) site (4820 m depth in the western North Atlantic) periods of strong currents and sediment erosion alternate with periods of weak flow and massive deposition. We investigated the impact of this atypical hydrodynamic environment on the isopod fauna by testing for a difference in composition between the HEBBLE site and a tranquil location, the Deep Ocean Mining Environmental Study (DOMES) site A ( ca. 5000 m) in the equatorial Pacific. Epifaunal isopods were significantly less abundant at the HEBBLE site than at the comparison site despite significantly greater total isopod numbers at the HEBBLE site. We suggest that the hydrodynamic regime puts epifaunal isopods at risk, making them rare at the HEBBLE site.

  12. Local extirpations and regional declines of endemic upper beach invertebrates in southern California

    NASA Astrophysics Data System (ADS)

    Hubbard, D. M.; Dugan, J. E.; Schooler, N. K.; Viola, S. M.

    2014-10-01

    Along the world's highly valued and populous coastlines, the upper intertidal zones of sandy beach ecosystems and the biodiversity that these zones support are increasingly threatened by impacts of human activities, coastal development, erosion, and climate change. The upper zones of beaches typically support invertebrates with restricted distributions and dispersal, making them particularly vulnerable to habitat loss and fragmentation. We hypothesized that disproportionate loss or degradation of these zones in the last century has resulted in declines of upper shore macroinvertebrates in southern California. We identified a suite of potentially vulnerable endemic upper beach invertebrates with direct development, low dispersal and late reproduction. Based on the availability of printed sources and museum specimens, we investigated historical changes in distribution and abundance of two intertidal isopod species (Tylos punctatus, Alloniscus perconvexus) in southern California. Populations of these isopods have been extirpated at numerous historically occupied sites: T. punctatus from 16 sites (57% decrease), and A. perconvexus from 14 sites (64% decrease). During the same period, we found evidence of only five colonization events. In addition, the northern range limit of the southern species, T. punctatus, moved south by 31 km (8% of range on California mainland) since 1971. Abundances of T. punctatus have declined on the mainland coast; only three recently sampled populations had abundances >7000 individuals m-1. For A. perconvexus populations, abundances >100 individuals m-1 now appear to be limited to the northern part of the study area. Our results show that numerous local extirpations of isopod populations have resulted in regional declines and in greatly reduced population connectivity in several major littoral cells of southern California. Two of the six major littoral cells (Santa Barbara and Zuma) in the area currently support 74% of the remaining isopod populations. These isopods persist primarily on relatively remote, ungroomed, unarmored beaches with restricted vehicle access and minimal management activity. These predominantly narrow, bluff-backed beaches also support species-rich upper beach assemblages, suggesting these isopods can be useful indicators of biodiversity. The high extirpation rates of isopod populations on the southern California mainland over the last century provide a compelling example of the vulnerability of upper beach invertebrates to coastal urbanization. Climate change and sea level rise will exert further pressures on upper beach zones and biota in southern California and globally. In the absence of rapid implementation of effective conservation strategies, our results suggest many upper intertidal invertebrate species are at risk.

  13. Patterns of taxonomic diversity among terrestrial isopods

    PubMed Central

    Sfenthourakis, Spyros; Taiti, Stefano

    2015-01-01

    Abstract The publication of the world catalog of terrestrial isopods some ten years ago by Schmalfuss has facilitated research on isopod diversity patterns at a global scale. Furthermore, even though we still lack a comprehensive and robust phylogeny of Oniscidea, we do have some useful approaches to phylogenetic relationships among major clades which can offer additional insights into isopod evolutionary dynamics. Taxonomic diversity is one of many approaches to biodiversity and, despite its sensitiveness to biases in taxonomic practice, has proved useful in exploring diversification dynamics of various taxa. In the present work, we attempt an analysis of taxonomic diversity patterns among Oniscidea based on an updated world list of species containing 3,710 species belonging to 527 genera and 37 families (data till April 2014). The analysis explores species diversity at the genus and family level, as well as the relationships between species per genera, species per families, and genera per families. In addition, we consider the structure of isopod taxonomic system under the fractal perspective that has been proposed as a measure of a taxon’s diversification. Finally, we check whether there is any phylogenetic signal behind taxonomic diversity patterns. The results can be useful in a more detailed elaboration of Oniscidea systematics. PMID:26261437

  14. Beach Erosion

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Two miles of beach at Cape Canaveral eroded by construction of a port and jetties was recently restored. Such work in harbors of many cities often disrupts normal flow of sand for many miles along coasts. Brevard County, FL residents now enjoy a 400 ft. wide public beach in an area in imminent danger of destructive erosion just a year previously. Before and after aerial photos show how more than two miles of beach were rebuilt with 2.7 million cubic yards of sand helping abate the erosion problem caused by construction of jetties. NASA volunteered its remote-sensing technology and instrumented aircraft to provide low-altitude color infrared photography about every three months since 1972.

  15. Bacteriophage WO in Wolbachia infecting terrestrial isopods.

    PubMed

    Braquart-Varnier, Christine; Grève, Pierre; Félix, Christine; Martin, Gilbert

    2005-11-18

    Wolbachia are maternally inherited intracellular alpha-proteobacteria that infect a wide range of arthropods. They are associated with a number of different reproductive phenotypes in arthropods and nematodes. In isopod crustacean, Wolbachia are responsible for feminization of genetic males in many species, and for cytoplasmic incompatibility in two species. In this paper, we report the first detection of phage WO from Wolbachia infecting terrestrial isopods. All Wolbachia strains tested in this study were infected with phage WO. Based on the orf7 phage sequence, we identified three different phage sequences in four Wolbachia strains. The phage of Wolbachia infecting Armadillidium vulgare seems to be not active, unlike other phages WO previously described in arthropods. PMID:16198306

  16. Burrowing inhibition by fine textured beach fill: Implications for recovery of beach ecosystems

    NASA Astrophysics Data System (ADS)

    Viola, Sloane M.; Hubbard, David M.; Dugan, Jenifer E.; Schooler, Nicholas K.

    2014-10-01

    Beach nourishment is often considered the most environmentally sound method of maintaining eroding shorelines. However, the ecological consequences are poorly understood. Fill activities cause intense disturbance and high mortality and have the potential to alter the diversity, abundance, and distribution of intertidal macroinvertebrates for months to years. Ecological recovery following fill activities depends on successful recolonization and recruitment of the entire sandy intertidal community. The use of incompatible sediments as fill material can strongly affect ecosystem recovery. We hypothesized that burrowing inhibition of intertidal animals by incompatible fine fill sediments contributes to ecological impacts and limits recovery in beach ecosystems. We experimentally investigated the influence of intertidal zone and burrowing mode on responses of beach invertebrates to altered sediment texture (28-38% fines), and ultimately the potential for colonization and recovery of beaches disturbed by beach filling. Using experimental trials in fill material and natural beach sand, we found that the mismatched fine fill sediments significantly inhibited burrowing of characteristic species from all intertidal zones, including sand crabs, clams, polychaetes, isopods, and talitrid amphipods. Burrowing performance of all five species we tested was consistently reduced in the fill material and burrowing was completely inhibited for several species. The threshold for burrowing inhibition by fine sediment content in middle and lower beach macroinvertebrates varied by species, with highest sensitivity for the polychaete (4% fines, below the USA regulatory limit of 10% fines), followed by sand crabs and clams (20% fines). These results suggest broader investigation of thresholds for burrowing inhibition in fine fill material is needed for beach animals. Burrowing inhibition caused by mismatched fill sediments exposes beach macroinvertebrates to stresses, which could depress recruitment and survival at all intertidal zones. Our results suggest use of incompatible fine fill sediments from dredging projects creates unsuitable intertidal habitat that excludes burrowing macroinvertebrates and could delay beach ecosystem recovery. Through effects on beach invertebrates that are prey for shorebirds and fish, the ecological impacts of filling with mismatched fine sediments could influence higher trophic levels and extend beyond the beach itself.

  17. Towards a characterization of the locomotor activity rhythm of the supralittoral isopod Tylos europaeus.

    PubMed

    Bohli-Abderrazak, Dhouha; Ayari, Amel; Morgan, Elfed; Nasri-Ammar, Karima

    2012-03-01

    Freshly collected samples of Tylos europaeus from Korba beach (northeast of Tunisia) were housed in an environmental cabinet at controlled temperature (18°C?±?.5°C) and photoperiod. Locomotor activity was recorded under two photoperiodic regimens by infrared actography every 20?min by multichannel data loggers. One regimen simulated the natural light-dark cycle on the day of collection, whereas the second imposed a state of continuous darkness on all individuals. Under entraining conditions, the animals displayed rhythmic activity, in phase with the period of darkness, whereas in continuous darkness these isopods exhibited a strong endogenous rhythm with circadian and semidiurnal components at mean periods of ? (h:min)?=?25:09?±?01:02?h and ??=?12:32?±?00:26?h, respectively. Under free-running conditions, this endogenous rhythm showed significant intraspecific variability. PMID:22324555

  18. Pathogenic effect of entomopathogenic nematode-bacterium complexes on terrestrial isopods.

    PubMed

    Sicard, Mathieu; Raimond, Maryline; Prats, Olivier; Lafitte, Alexandra; Braquart-Varnier, Christine

    2008-09-01

    In this study, we evaluated the effect of entomopathogenic nematodes (EPNs) Steinernema carpocapsae, Steinernema feltiae and Heterorhabditis bacteriophora, symbiotically associated with bacteria of the genera Xenorhabdus or Photorhabdus, on the survival of eight terrestrial isopod species. The EPN species S. carpocapsae and H. bacteriophora reduced the survival of six isopod species while S. feltiae reduced survival for two species. Two terrestrial isopod species tested (Armadillidium vulgare and Armadillo officinalis) were found not to be affected by treatment with EPNs while the six other isopod species showed survival reduction with at least one EPN species. By using aposymbiotic S. carpocapsae (i.e. without Xenorhabdus symbionts), we showed that nematodes can be isopod pathogens on their own. Nevertheless, symbiotic nematodes were more pathogenic for isopods than aposymbiotic ones showing that bacteria acted synergistically with their nematodes to kill isopods. By direct injection of entomopathogenic bacteria into isopod hemolymph, we showed that bacteria had a pathogenic effect on terrestrial isopods even if they appeared unable to multiply within isopod hemolymphs. A developmental study of EPNs in isopods showed that two of them (S. carpocapsae and H. bacteriophora) were able to develop while S. feltiae could not. No EPN species were able to produce offspring emerging from isopods. We conclude that EPN and their bacteria can be pathogens for terrestrial isopods but that such hosts represent a reproductive dead-end for them. Thus, terrestrial isopods appear not to be alternative hosts for EPN populations maintained in the absence of insects. PMID:18346756

  19. Reference values for feeding parameters of isopods (Porcellioscaber, Isopoda, Crustacea).

    PubMed

    Drobne, Damjana; Drobne, Samo

    2014-01-01

    The advantage of using terrestrial isopods in toxicity studies is that a battery of parameters can be tested at different levels of biological complexity. Feeding parameters for example link organism level response to potential ecological consequences but a problem with using feeding parameters in toxicity tests with terrestrial isopods is their high variability. The aim of our study was to set benchmark values for feeding parameters for isopod Porcellioscaber (Isopoda, Crustacea) in laboratory-controlled experiments. In the work presented here, the daily feeding rate of the central 50% of the control population of Porcellioscaber and a correlation between feeding rate and isopod weight were set. Values outside these ranges need additional evaluation to increase the relevance of test outcomes. We suggest using benchmark values for feeding parameters as well as the coefficient of variation (a) to identify animals with altered feeding parameters with respect to controls, and (b) to assess the data quality in each experiment. PMID:25561844

  20. A massive infestation of sea snakes by cymothoid isopods.

    PubMed

    Saravanakumar, A; Balasubramanian, T; Raja, K; Trilles, Jean-Paul

    2012-06-01

    In this study, a massive infestation of the sea snake Enhydrina schistosa by the cymothoid isopod Nerocila serra, commonly parasitizing fishes, is reported for the first time from India. This isopod was found attached on the different parts of the body of the snake. According to the month, the parasitic prevalence ranged from 30.8 to 55.3%, increasing during the monsson period. It was higher in female than in male snakes. PMID:22223034

  1. External microflora of a marine wood-boring isopod.

    PubMed

    Boyle, P J; Mitchell, R

    1981-10-01

    Bacteria associated with the marine wood-boring isopod Limnoria lignorum were enumerated by acridine orange epifluorescence microscopy and by plate counts on several media; the plate-viable bacteria were isolated and identified. Similar procedures were followed to enumerate and identify bacteria associated with the wood substrate from which the isopods were collected and with the surrounding water from the isopod habitat. Approximately 1.4 x 10 bacterial cells were associated with each individual L. lignorum. Aeromonas hydrophila, Pseudomonas, and Vibrio were the most common genera in the isopod microflora. Wood from L. lignorum burrows had an associated bacterial flora of 1.6 x 10 cells per mg (damp weight). A. hydrophila also predominated in the wood microflora. The water from which the isopod population was collected contained 2.3 x 10 bacteria per ml. Pseudomonas and Vibrio species were very common in the water microflora, but A. hydrophila was not detected. Interactions between the isopod, its associated microorganisms, and the microorganisms within the wood substrate are discussed in the light of the known absence of a resident digestive tract microflora in these animals. PMID:16345871

  2. Global Diversification at the Harsh Sea-Land Interface: Mitochondrial Phylogeny of the Supralittoral Isopod Genus Tylos (Tylidae, Oniscidea)

    PubMed Central

    Hurtado, Luis A.; Lee, Eun J.; Mateos, Mariana; Taiti, Stefano

    2014-01-01

    The supralittoral environment, at the transition between sea and land, is characterized by harsh conditions for life. Nonetheless, evolution of terrestrial isopods (Oniscidea), the only group of Crustacea fully adapted to live on land, appears to have involved a transitional step within the supralittoral. The two most basal oniscidean lineages (Ligiidae and Tylidae) have representatives that successfully colonized the supralittoral. One of them is the genus Tylos, which is found exclusively in supralittoral sandy beaches from tropical and subtropical coasts around the world. Comprehensive phylogenetic hypotheses for this genus are lacking, which are necessary for understanding the evolution and biogeography of a lineage that successfully diversified in the harsh sea-land interface. Herein, we studied the phylogenetic relationships among 17 of the 21 currently recognized species of the genus Tylos, based on sequences from four mitochondrial genes (Cytochrome Oxidase I, Cytochrome b, 16S rDNA, and 12S rDNA). Maximum Likelihood and Bayesian phylogenetic analyses identified several lineages with deep divergences and discrete geographic distributions. Phylogenetic and distributional patterns of Tylos provide important clues on the biogeography and evolution of this group. Large divergences among the most basal clades are consistent with ancient splits. Due to the biological characteristics of Tylos, which likely prevent dispersal of these isopods across vast oceanic scales, we argue that tectonic events rather than trans-oceanic dispersal explain the distribution of Tylos in different continents. Overwater dispersal, however, likely enabled range expansions within some basins, and explains the colonization of volcanic oceanic islands. Present-day distributions were also likely influenced by sea level and climate changes. High levels of allopatric cryptic genetic differentiation are observed in different regions of the world, implying that the dispersal abilities of Tylos isopods are more limited than previously thought. Our results indicate that a taxonomic revision of this group is necessary. PMID:24736501

  3. Global diversification at the harsh sea-land interface: mitochondrial phylogeny of the supralittoral isopod genus Tylos (Tylidae, Oniscidea).

    PubMed

    Hurtado, Luis A; Lee, Eun J; Mateos, Mariana; Taiti, Stefano

    2014-01-01

    The supralittoral environment, at the transition between sea and land, is characterized by harsh conditions for life. Nonetheless, evolution of terrestrial isopods (Oniscidea), the only group of Crustacea fully adapted to live on land, appears to have involved a transitional step within the supralittoral. The two most basal oniscidean lineages (Ligiidae and Tylidae) have representatives that successfully colonized the supralittoral. One of them is the genus Tylos, which is found exclusively in supralittoral sandy beaches from tropical and subtropical coasts around the world. Comprehensive phylogenetic hypotheses for this genus are lacking, which are necessary for understanding the evolution and biogeography of a lineage that successfully diversified in the harsh sea-land interface. Herein, we studied the phylogenetic relationships among 17 of the 21 currently recognized species of the genus Tylos, based on sequences from four mitochondrial genes (Cytochrome Oxidase I, Cytochrome b, 16S rDNA, and 12S rDNA). Maximum Likelihood and Bayesian phylogenetic analyses identified several lineages with deep divergences and discrete geographic distributions. Phylogenetic and distributional patterns of Tylos provide important clues on the biogeography and evolution of this group. Large divergences among the most basal clades are consistent with ancient splits. Due to the biological characteristics of Tylos, which likely prevent dispersal of these isopods across vast oceanic scales, we argue that tectonic events rather than trans-oceanic dispersal explain the distribution of Tylos in different continents. Overwater dispersal, however, likely enabled range expansions within some basins, and explains the colonization of volcanic oceanic islands. Present-day distributions were also likely influenced by sea level and climate changes. High levels of allopatric cryptic genetic differentiation are observed in different regions of the world, implying that the dispersal abilities of Tylos isopods are more limited than previously thought. Our results indicate that a taxonomic revision of this group is necessary. PMID:24736501

  4. Problems caused by isopod parasites in commercial fishes.

    PubMed

    Rameshkumar, Ganapathy; Ravichandran, Samuthirapandian

    2014-03-01

    Crustaceans are found in every type of aquatic ecosystem, and there are species adapted to extremes of temperature, pressure, salinity, and even anoxia. Parasitic isopods are typically marine and usually inhabit the warmer seas. They are blood-feeding; several species settle in the buccal cavity of fish, others live in the gill chamber or on the body surface including the fins. Isopods can cause morbidity and mortality in captive fish populations. The damage of gill filaments thus was not only due to the feeding but also by the pressure exerted by the dorsal side of the parasite. Erosion of gill lamellae, damage of gill rakers and pale gills were the severe gross lesions observed as a consequence of isopod infestation. Infested fish exhibited histopathological anomalies such as tissue reactions, primarily associated with the formation of granulomas consisted of macrophages and epithelioid cells, which are occasionally surrounded by a thin rim of fibroblasts. A marked increase in the size of the parasite is associated with the development of marsupium full of juvenile parasite. The infestation usually pressure atrophy often accompanies the presence of larger parasites. They may lead to economic losses in commercial species of fish. Thus, treating fishes infected with isopods without treating their environment may only provide temporary relief. It is also important to recognize the potential for secondary infections associated with severe isopod infections. PMID:24505194

  5. Virtual Beach Manager Toolset

    EPA Science Inventory

    The Virtual Beach Manager Toolset (VB) is a set of decision support software tools developed to help local beach managers make decisions as to when beaches should be closed due to predicted high levels of water borne pathogens. The tools are being developed under the umbrella of...

  6. BEACHES HEALTH SURVEY

    EPA Science Inventory

    Baterial samples were taken at swimming beaches (primarily freshwater beaches) in Region 10 while evaluating potential bacterial sources (e.g., people, cattle, pets, septic systems, runoff, birds). For each beach selected, the preferred sampling is: background, low/no use period...

  7. Community structure and intertidal zonation of the macroinfauna in intermediate sandy beaches in temperate latitudes: North coast of Spain

    NASA Astrophysics Data System (ADS)

    Rodil, I. F.; Lastra, M.; Sánchez-Mata, A. G.

    2006-03-01

    Nineteen intermediate exposed sandy beaches, located along the northern coast of Spain, were sampled during the summer 1999. Data from 10 of the beaches, located at the eastern part of this coast, were previously reported to evaluate environmental factors affecting benthic macrofauna. Data from nine of the beaches, located at the western part of this coast, were included to compare community structure and intertidal zonation of the macroinfauna on intermediate sandy beaches in temperate latitudes. Morphodynamic parameters such as Dean's parameter ( ?), Beach State Index (BSI) and relative tide range (RTR) were estimated at each beach. Beach length, width, intertidal slope, medium grain size, sorting, swash amplitude and wave characteristics were also analyzed. The highest macroinfaunal densities and biomass occurred at the mid and lower shore levels of each beach. Crustaceans, mainly cirolanid isopods, were the dominant group found on these beaches, whereas molluscs were the least representative. In general, the relationship between community structure and beach morphodynamics was similar to that found for the macroinfauna worldwide suggesting that macroinfauna in intermediate sandy beaches is affected, in the same way, by the physical processes associated with different beach types. Histograms and kite diagrams representing the intertidal distribution of the macroinfauna and multivariate analysis were used to show the zonation pattern on these exposed beaches. Intertidal slope values and beach profile pattern were found similar in all the beaches sampled. We hypothesized that this particular beach profile could influence the pattern of macroinfauna zonation. All the 19 beaches have two zones in common: the supralittoral zone of air breathers present on all shores at and above the drift line and the littoral zone extending from the drift line down the midshore to just above the water table outcrop. Ordination analyses identified two possible zones within the lower beach levels on seven of the beaches, but this cannot be clearly established. The Monte Carlo permutation test was used to select beach slope, length and wave height as the best predictor variables of macroinfaunal characteristics and it seems that the species most affected by the main variables showed the clearest zonation on the beaches.

  8. Is the HEBBLE isopod fauna hydrodynamically modified? A second test

    NASA Astrophysics Data System (ADS)

    Thistle, David; Wilson, George D. F.

    1996-04-01

    Several times per year, the High Energy Benthic Boundary Layer Experiment (HEBBLE) site (4820 m depth, 40°27'N 62°20'W) experiences benthic storms during which near-bottom flows can erode millimeters of sediment. Thistle and Wilson ( Deep-Sea Research, 34 1987, 73-87) predicted that isopods that inhabited the surface of the sediment would be relatively rare at the HEBBLE site compared to those at quiescent deep-sea sites. They tested this prediction by comparing the composition of the HEBBLE isopod fauna to that of a quiescent site and found a significant difference in the predicted direction. Although this result was encouraging, the strength of their inference was limited because only one site from each type of environment had been compared. We performed a second test of Thistle and Wilson's hypothesis by comparing the composition of the isopod fauna from two additional physically quiescent locations (4500 m depth, 14°40'N 125°26'W, and 4800 m depth, 12°57'N 128°19.5'W) to that of the HEBBLE site. Those isopods that are thought to be exposed to the erosion caused by storms occurred in a significantly greater proportion of the samples at the quiescent sites than at the HEBBLE site, a result consistent with Thistle and Wilson's hypothesis.

  9. Thermal stress studies on selected zooplankton species and an isopod

    SciTech Connect

    Bunting, D.L.; Cheper, N.J.

    1980-06-01

    Laboratory determination of temperature stress levels and assessment of their ecological consequences was carried out for selected zooplankton species to develop data for ecological impact associated with industrial use of natural water for cooling. An included literature search revealed substantial fish and benthos data, but little on stress temperature effects on zooplankton. Information was gathered on two cladocerans, four copepods and an isopod.

  10. Iridovirus infection in terrestrial isopods from Sicily (Italy).

    PubMed

    Lupetti, Pietro; Montesanto, Giuseppe; Ciolfi, Silvia; Marri, Laura; Gentile, Mariangela; Paccagnini, Eugenio; Lombardo, Bianca Maria

    2013-10-01

    During our researches on systematics and ecology of terrestrial isopods, carried out in western Sicily, some specimens showing a blue-purple coloration were collected; they belonged to four species: Armadillidium decorum Brandt, 1833, Trichoniscus panormidensis Montesanto et al., 2011, Philoscia affinis Verhoeff, 1908, Porcellio siculoccidentalis Viglianisi et al., 1992. We hypothesized that such coloration could be due, as reported in literature, to characteristic paracrystalline arrays of virions inside the tissues of blue colored specimens. Ultrastructural observations by transmission electron microscopy, on tissues of A. decorum, showed the presence of electron-dense viral particles, with a diameter of nearly 0.12μm. Dual-axis tomography, performed on specimens of A. decorum, evidenced an icosahedral structure of viral particles matching with that of Isopod Iridescent Virus (IIV). Molecular analysis, on 254bp portion of the major capsid protein (MCP) gene, allowed to place the virus into IIV-31 group, already known for other oniscidean species. The symptoms of infected individuals and the course of the disease were followed in laboratory, indicating similarities with other studies on Isopod Iridoviruses. Moreover, some notes on reproduction of infected ovigerous females are reported. Our data support unequivocal and direct evidences for the first case of IIV infection in terrestrial isopods reported in Italy. PMID:23756498

  11. Detached macroalgae: Its importance to inshore sandy beach fauna

    NASA Astrophysics Data System (ADS)

    Orr, Kyla K.; Wilding, Thomas A.; Horstmeyer, Lena; Weigl, Simon; Heymans, Johanna J.

    2014-10-01

    Kelp forests shed a large proportion of their biomass through storm-mediated defoliation, senescence of kelp blades, and constant erosion of particulate organic matter from the kelp fronds. Much of this detached macroalgae drifts in the water column and is deposited on intertidal zones of beaches. Detached macroalgae may provide inshore sandy beach fauna with refuge and food subsidies in an exposed and bare environment, with limited in situ primary production. We evaluated the relationship between detached macroalgae and the density of inshore fauna, where 'inshore' was the body of water extending from low water seawards for approximately 50 m. Inshore fauna were sampled using a push-net (1 mm mesh) on 11 beaches, and using a beam-trawl (4 mm mesh) on a subset of 8 beaches. On each beach, the density of detached macroalgae in the water column was quantified, together with a suite of physico-chemical beach characteristics. Push-net samples principally comprised omnivorous and detritivorous crustaceans such as gammarid amphipods, mysids and valviferan isopods, which have limited swimming abilities and reside inshore year-round. Beam-trawl fauna were mainly carnivorous decapods and fish, which undergo seasonal inshore-offshore migrations to utilize sandy beaches as nursery habitats. Linear models predicted increases of 11% (95% CI: 3.5-19%) and 2.4% (95% CI: 0.7-4.2%) in the density of push-net and beam-trawl fauna, respectively, with a 1 ℓ.100 m-3 increase in detached macroalgae. This suggests that detached macroalgae is more important in the provision of food and shelter to small, weak-swimming detritivores/omnivores than to larger and more mobile predators. The densities of large predators were mostly explained by physical beach characteristics, which overshadowed the role of macroalgae. Maximum abundances of decapods and fish were found on wide, flat beaches with low wave heights. Large accumulations of macroalgae may inhibit the foraging efficiencies of predatory fauna such as decapods and fish, and restrict their abundance.

  12. The trophic significance of the invasive seaweed Sargassum muticum in sandy beaches

    NASA Astrophysics Data System (ADS)

    Rossi, Francesca; Olabarria, Celia; Incera, Mónica; Garrido, Josefina

    2010-01-01

    Native and exotic seaweeds frequently lie on the beach and sustain part of the benthic food web. However, the role of exotic seaweeds as food sources for beach consumers has been poorly studied. We studied the temporal and spatial variability in the trophic significance of the invasive brown seaweed Sargassum muticum on sandy beaches. We measured the stable isotopes ( ?13C and ?15N) in the tissues of S. muticum and of invertebrate consumers and estimated the dietary biomass proportion of S. muticum during four sampling dates at two beaches and heights on the shore. Samples were collected from eight pitfall traps placed at a distance of 2 m from each other. Detrital macroalgae and seagrasses were also collected by hand within an area of 30 cm around each pitfall trap. We measured the spatial and temporal variability in the isotope composition of the beach consumers and of S. muticum using different models of analyses of variance. We then calculated the biomass proportion of S. muticum to the animal diet with a two-isotopic mixing model. The invasive alga S. muticum seemed to be one of the main food sources for the amphipod Talitrus saltator and, to a less extent, for the isopod Tylos europaeus. The importance of S. muticum was however temporally variable and decreased during spring (in March and May), probably due to the availability of native macrophytes. The supply of invasive wrack to beach food webs thus deserves more attention if we want to understand their role in influencing food web dynamics.

  13. Human Health at the Beach

    MedlinePLUS

    ... Other Beach Safety Topics Beach Related Illnesses A water quality warning sign advising swimmers to avoid contact with ... a source of longer-term data about beach water quality. EPA created BEACON to provide the Agency's requirement ...

  14. Pyrethroid pesticide effects on behavioral responses of aquatic isopods to danger cues.

    PubMed

    Huynh, Carolyn K; Poquette, Signe R; Whitlow, W Lindsay

    2014-04-01

    The present study sought to evaluate the behavioral responses of non-target organisms in order to determine whether phototactic responses of isopods to danger cues are altered as a function of exposure to the pyrethroid pesticides ?-cyhalothrin and bifenthrin. Experiments conducted on Gnorimosphaeroma oregonensis identified sublethal behavioral responses to pyrethroids, ?-cyhalothrin and bifenthrin at concentrations 0.15 ng/mL, 0.025 ng/mL, and 0.005 ng/mL. Experimental setup tested isopod phototactic responses across six treatments: control, pyrethroid, hemolymph, predator, hemolymph + pyrethroid, and predator + pyrethroid. Isopods exhibited no preference for phototactic responses in the control and pyrethroid treatments. When exposed to danger cues (hemolymph or predator), isopods exhibited significant negative phototaxis, as expected. When exposure to danger cues was combined with pyrethroids, isopods again exhibited no preference for phototactic response. Experiments indicate that pyrethroids diminish isopod's negatively phototactic response to danger cues. PMID:24390114

  15. Louisiana's statewide beach cleanup

    USGS Publications Warehouse

    Lindstedt, Dianne M.; Holmes, Joseph C., Jr.

    1989-01-01

    Litter along Lousiana's beaches has become a well-recognized problem. In September 1987, Louisiana's first statewide beach cleanup attracted about 3300 volunteers who filled 16,000 bags with trash collected along 15 beaches. An estimated 800,173 items were gathered. Forty percent of the items were made of plastic and 11% were of polystyrene. Of all the litter collected, 37% was beverage-related. Litter from the oil and gas, commercial fishing, and maritime shipping industries was found, as well as that left by recreational users. Although beach cleanups temporarily rid Louisiana beaches of litter, the real value of the effort is in public participation and education. Civic groups, school children, and individuals have benefited by increasing their awareness of the problems of trash disposal.

  16. Mouthparts and their setae of the intertidal isopod Cirolana harfordi.

    PubMed

    Thomson, M

    2013-11-01

    The cirolanid isopod Cirolana harfordi is described as a scavenger and a predator that lives in the intertidal region. In order to understand the microanatomy of the mouthparts and the setae that allow this animal to handle and eat its food, a scanning electron microscopy study was conducted. C. harfordi displays a variety in the types of setae distributed on its mouthparts in a site-specific fashion, including complex setae placed on the medial edge of the maxilliped and maxilla. Terminal pores in some setae were found to contain a cupule, which is a hemispherical structure, housed in the concave recess of the pore, which demonstrates that the pore is more than merely a thinning of the cuticle as has been proposed. Future studies on setal morphology are needed for comparative microanatomy of cirolanid isopods. PMID:24032633

  17. Occurrence of cymothoid isopod from Miri, East Malaysian marine fishes.

    PubMed

    Anand Kumar, A; Rameshkumar, Ganapathy; Ravichandran, Samuthirapandian; Priya, E Rethna; Nagarajan, Ramasamy; Leng, Alex Goh Kwang

    2015-06-01

    To identify the isopod parasite, which has been recorded from Miri, East Malaysian marine fishes. During the present study, four cymothoid isopods are reported three genera, including Cymothoa eremita, Lobothorax typus, Nerocila longispina and Nerocila loveni. Nerocila longispina and N. loveni are also previously reported from Malaysia and two additional cymothoids C. eremita and L. typus are reported for the first record of Miri coast, East Malaysia. New hosts were identified for N. loveni on Chirocentrus dorab for the first time in the world fauna. The Parasitological indexes were calculated. The site of attachment of the parasites on their hosts was also observed. These parasites can cause the damage in gill, eye and internal organ including swim bladder. Marine fish parasitology is a rapidly developing field of aquatic science. PMID:26064001

  18. Size dependent differences in litter consumption of isopods: preliminary results

    PubMed Central

    Vilisics, Ferenc; Szekeres, Sándor; Hornung, Elisabeth

    2012-01-01

    Abstract A series of experiments were applied to test how leaf orientation within microcosms affect consumption rates (Experiment 1), and to discover intra-specific differences in leaf litter consumption (Experiment 2) of the common isopod species Porcellio scaber and Porcellionides pruinosus. A standardised microcosm setup was developed for feeding experiments to maintain standard conditions. A constant amount of freshly fallen black poplar litter was provided to three distinct size class (small, medium, large) of woodlice. We measured litter consumption after a fortnight. We maintained appr. constant isopod biomass for all treatments, and equal densities within each size class. We hypothesized that different size classes differ in their litter consumption, therefore such differences should occur even within populations of the species. We also hypothesized a marked difference in consumption rates for different leaf orientation within microcosms. Our results showed size-specific consumption patterns for Porcellio scaber: small adults showed the highest consumption rates (i.e. litter mass loss / isopod biomass) in high density microcosms, while medium-sized adults of lower densities ate the most litter in containers. Leaf orientation posed no significant effect on litter consumption. PMID:22536112

  19. Ecology of exposed sandy beaches in northern Spain: Environmental factors controlling macrofauna communities

    NASA Astrophysics Data System (ADS)

    Lastra, M.; de La Huz, R.; Sánchez-Mata, A. G.; Rodil, I. F.; Aerts, K.; Beloso, S.; López, J.

    2006-02-01

    Thirty-four exposed sandy beaches on the northern coast of Spain (from 42°11' to 43°44'N, and from 2°04' to 8°52' W; ca. 1000 km) were sampled over a range of beach sizes, beach morphodynamics and exposure rates. Ten equally spaced intertidal shore levels along six replicated transects were sampled at each beach. Sediment and macrofauna samples were collected using corers to a depth of 15 cm. Morphodynamic characteristics such as the beach face slope, wave environment, exposure rates, Dean's parameter and Beach State Index were estimated. Biotic results indicated that in all the beaches the community was dominated by isopods, amphipods and polychaetes, mostly belonging to the detritivorous-opportunistic trophic group. The number of intertidal species ranged from 9 to 31, their density being between 31 and 618 individuals m - 2 , while individuals per linear metre (m - 1 ) ranged from 4962 to 17 2215. The biomass, calculated as total ash-free dry weight (AFDW) varied from 0.027 to 2.412 g m - 2 , and from 3.6 to 266.6 g m - 1 . Multiple regression analysis indicated that number of species significantly increased with proximity to the wind-driven upwelling zone located to the west, i.e., west-coast beaches hosted more species than east-coast beaches. The number of species increased with decreasing mean grain size and increasing beach length. The density of individuals m - 2 increased with decreasing mean grain size, while biomass m - 2 increased with increasing food availability estimated as chlorophyll-a concentration in the water column of the swash zone. Multiple-regression analysis indicated that chlorophyll-a in the water column increased with increasing western longitude. Additional insights provided by single-regression analysis showed a positive relationship between the number of species and chlorophyll-a, while increasing biomass occurred with increasing mean grain size of the beach. The results indicate that community characteristics in the exposed sandy beaches studied are affected by physical characteristics such as sediment size and beach length, but also by other factors dependent on coastal processes, such as food availability in the water column.

  20. 76 FR 52344 - Application for an Incidental Take Permit for the Madison Cave Isopod From Dominion Virginia...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-22

    ... Fish and Wildlife Service Application for an Incidental Take Permit for the Madison Cave Isopod From... the permit application from Dominion Virginia Power for incidental take of the Madison Cave isopod... application from Dominion Virginia Power for incidental take of the federally listed Madison Cave isopod...

  1. NATIONAL HEALTH SURVEY OF BEACHES

    EPA Science Inventory

    Resource Purpose:The annual Beach Survey is designed to gather information about beach water quality, standards, monitoring, and beach health advisories or closures issued during the previous year's bathing season. Each year the survey updates previously submitted beach i...

  2. NHD INDEXED LOCATIONS FOR BEACH

    EPA Science Inventory

    Beach locational data for BEACH Act. Beach locations are coded onto route.drain (Transport and Coastline Reach) feature of NHD to create Point Events and Linear Events. Beach locations are coded onto region.rch (Waterbody Reach) feature of NHD to create NHD Waterbody Shapefiles...

  3. The response of macrofauna communities and shorebirds to macrophyte wrack subsidies on exposed sandy beaches of southern California

    NASA Astrophysics Data System (ADS)

    Dugan, Jenifer E.; Hubbard, David M.; McCrary, Michael D.; Pierson, Mark O.

    2003-10-01

    To investigate the influence of marine macrophyte wrack subsidies on community structure, relationships between community attributes, including species richness, abundance, and biomass of macrofauna and abundance of shorebirds, and a variety of factors, including the standing crop of wrack and beach morphodynamics, were examined on 15 exposed sandy beaches on the southern California coast. The beaches sampled were primarily modally intermediate morphodynamic types, and three were groomed regularly. Species richness, abundance, and biomass of the macrofauna were high compared to values reported for similar beach types in other regions and were not predicted by morphodynamics or other physical factors. Overall species richness and abundance, and the species richness, abundance, and biomass of wrack-associated fauna and selected taxa were significantly correlated with the standing crop of macrophyte wrack. Wrack-associated macrofauna, such as amphipods, isopods, and insects, made up an average of >37% of the species on ungroomed beaches and comprised 25% or more of the total abundance on half of those beaches. The abundance of two shorebird species, plovers that forage using visual cues, was positively correlated with the standing crop of wrack and with the abundance of wrack-associated invertebrates. Significant differences in community structure, including depressed species richness, abundance, and biomass of macrofauna, especially for wrack-associated taxa, were associated with beach grooming and provided strong evidence for the bottom-up effects of wrack subsidies. Grooming also reduced the prey available to vertebrate predators, such as shorebirds. Substantial ecological effects of the large-scale disturbance and removal of organic material, food resources, and habitat are associated with beach grooming. These results suggest that macrophyte wrack subsidies strongly influence macrofaunal community structure, higher trophic levels, and ecological processes on exposed sandy beaches. The supply of macrophyte wrack should be considered as a factor in ecological studies of exposed sandy beaches, particularly where macrophyte production is high.

  4. Detection of Wolbachia (Alphaproteobacteria: rickettsiales) in three species of terrestrial isopods (crustacea: isopoda: oniscidea) in Brazil

    PubMed Central

    Zimmermann, Bianca Laís; Almerão, Maurício Pereira; Bouchon, Didier; Araujo, Paula Beatriz

    2012-01-01

    Terrestrial isopods are widely infected with Wolbachia. However, little is known about the presence of bacteria in the Neotropical species. The objective of this study was to test the hypothesis of presence of Wolbachia infection in the native species of terrestrial isopods, Atlantoscia floridana and Circoniscus bezzii, and in the introduced species Burmoniscus meeusei. PMID:24031883

  5. A comparison of test systems for assessing effects of metals on isopod ecological functions.

    PubMed

    Van Wensem, J; Krijgsman, M; Postma, J F; Van Westrienen, R W; Wezenbeek, J M

    1992-10-01

    The effects of metals on the isopod Porcellio scaber and the implication of metal pollution for the functioning of isopods in soil decomposition processes were determined. The experiments were carried out using two test systems, a simple test container without natural substrate and a micro-ecosystem with leaf litter, the latter being more comparable to the field situation. Metals were offered to the isopods by feeding artificially contaminated litter and litter from contaminated field sites. The Cd concentrations in isopods in test containers with ground litter as food were similar to those in isopods in micro-ecosystems with intact leaves as food. Exposure to artificially contaminated litter with Cd alone or litter from contaminated field sites with Cd, Pb, Zn, and Cu resulted in comparable Cd concentrations in the isopods. Growth of the isopods was not affected by Cd or by the combination of Cd, Pb, Zn, and Cu, but differed between the test systems. Fragmentation activity of isopods decreased in litter containing 155 nmol/g Cd and 33500 nmol/g Zn, sampled at a contaminated field site. CO2 production from micro-ecosystems decreased at a concentration of 1010 nmol/g Cd, but NH4 and NO3 concentrations in the litter did not respond to Cd. Isopod growth was better in micro-ecosystems. These systems are therefore recommended for ecotoxicity tests using isopods. After comparison with literature data it was concluded that the bioavailability of Cd in laboratory tests is often higher than the bioavailability in the field at the same total concentrations. This may be due to environmental heterogeneity; this gives animals food choice and is absent in many laboratory test systems. For the quantification of a laboratory-field extrapolation factor for general use, more detailed information is needed than is available now. PMID:1280586

  6. BACTERIA, BEACHES AND SWIMMABLE WATERS: INTRODUCING VIRTUAL BEACH

    EPA Science Inventory

    Safe beaches meet water quality standards and are valued for their aesthetics and the recreational opportunities that they afford. In the United States recreational water quality assessments and beach closure decisions are presently based on samples of enterococci or Escherichia ...

  7. Virtual Beach: Decision Support Tools for Beach Pathogen Prediction

    EPA Science Inventory

    The Virtual Beach Managers Tool (VB) is decision-making software developed to help local beach managers make decisions as to when beaches should be closed due to predicted high levels of water borne pathogens. The tool is being developed under the umbrella of EPA's Advanced Monit...

  8. Morphodynamics of Prograding Beaches

    NASA Astrophysics Data System (ADS)

    Ruggiero, P.

    2012-12-01

    Long-term coastal evolution often results from the cumulative effects of small residual differences between relatively large signals. In light of dire projections of sea level rise over the next several decades to century, there is a strong societal need for accurate forecasts of net interannual- to decadal-scale coastal change. However, our present understanding of the processes responsible for storm-induced erosion and coastal recession is significantly more advanced than our knowledge of coastal recovery during calm periods. To investigate the processes and morphodynamics associated with progading beaches we synthesize findings from a long-term (15 years) beach morphology monitoring program in the U.S. Pacific Northwest. Most of the beaches along the Columbia River littoral cell (northwest Oregon and southwest Washington) were eroded during the two intense winters of 1997/1998 (a major El Niño event) and 1998/1999 (a moderate La Niña event). Subsequent to these winters the beaches have exhibited net residual progradation of several meters per year resulting in significant shoreline advance. During this same period as many as two to three new foredunes formed with backshore beach profiles accumulating sand at rates of well over 10 m3/m/yr. Interestingly, these large signals of horizontal and vertical coastal advance have occurred on beaches in which nearshore morphological variability is dominated by net offshore sandbar migration. Net offshore sandbar migration follows a three-stage process; bar generation near the shoreline, seaward migration, and bar degeneration in the outer nearshore with a cyclic return period of approximately 4 to 5 years in the region. Gradients in alongshore sediment transport, net onshore directed cross-shore sediment transport within the surf zone, and cross-shore feeding from a shoreface out of equilibrium with forcing conditions may each be partially responsible for the sediment supplied to the beaches and dunes during the study period. In this paper we will exploit regional variability in physical (e.g. sediment supply) and ecological variables (e.g. % cover of exotic beach grass species and density) thought responsible for the varying rates and form of coastal advance in the region. These gradients allow us to test hypotheses regarding the relative role of the various controls on interannual- to decadal-scale coastal evolution.

  9. Virtual Beach 3: User's Guide

    EPA Science Inventory

    Virtual Beach version 3 (VB3) is a decision support tool that constructs site-specific statistical models to predict fecal indicator bacteria (FIB) concentrations at recreational beaches. VB3 is primarily designed for beach managers responsible for making decisions regarding beac...

  10. Tonic immobility in terrestrial isopods: intraspecific and interspecific variability

    PubMed Central

    Quadros, Aline Ferreira; Bugs, Priscila Silva; Araujo, Paula Beatriz

    2012-01-01

    Abstract Many arthropods, including terrestrial isopods, are capable of entering a state of tonic immobility upon a mechanical disturbance. Here we compare the responses to mechanical stimulation in three terrestrial isopods Balloniscus glaber, Balloniscus sellowii and Porcellio dilatatus. We applied three stimuli in a random order and recorded whether each individual was responsive (i.e. showed tonic immobility) or not and the duration of the response. In another trial we related the time needed to elicit tonic immobility and the duration of response of each individual. Balloniscus sellowii was the least responsive species and Porcellio dilatatus was the most, with 23% and 89% of the tested individuals, respectively, being responsive. Smaller Balloniscus sellowii were more responsive than larger individuals. Porcellio dilatatus responded more promptly than the Balloniscus spp. but it showed the shortest response. Neither sex, size nor the type of stimulus explained the variability found in the duration of tonic immobility. These results reveal a large variability in tonic immobility behavior, even between closely related species, which seems to reflect a species-specific response to predators with different foraging modes. PMID:22536106

  11. Molecular evolution of the androgenic hormone in terrestrial isopods.

    PubMed

    Cerveau, Nicolas; Bouchon, Didier; Bergès, Thierry; Grève, Pierre

    2014-04-25

    In crustaceans, the androgenic gland (AG), thanks to the synthesis of the androgenic gland hormone (AGH), controls the differentiation of the primary and secondary male sexual characters. In this study, we amplified 12 new AGH cDNAs in species belonging to five different families of the infra-order Ligiamorpha of terrestrial isopods. Putative essential amino acids for the production of a functional AGH protein exhibit signatures of negative selection and are strictly conserved including typical proteolytic cleavage motifs, a putative N-linked glycosylation motif on the A chains and the eight Cys positions. An insulin-like growth factor motif was also identified in Armadillidium AGH sequences. The phylogenetic relationships of AGH sequences allowed one to distinguish two main clades, corresponding to members of the Armadillidiidae and the Porcellionidae families which are congruent with the narrow specificity of AG heterospecific grafting. An in-depth understanding of the regulation of AGH expression would help deciphering the interaction between Wolbachia, widespread feminizing endosymbiotic bacteria in isopods, and the sex differentiation of their hosts. PMID:24561051

  12. Isolation and Characterization of Microsatellite Loci for the Isopod Crustacean Armadillidium vulgare and Transferability in Terrestrial Isopods

    PubMed Central

    Bech, Nicolas; Grandjean, Frédéric; Cordaux, Richard

    2013-01-01

    Armadillidium vulgare is a terrestrial isopod (Crustacea, Oniscidea) which harbors Wolbachia bacterial endosymbionts. A. vulgare is the major model for the study of Wolbachia-mediated feminization of genetic males in crustaceans. As a consequence of their impact on host sex determination mechanisms, Wolbachia endosymbionts are thought to significantly influence A. vulgare evolution on various grounds, including population genetic structure, diversity and reproduction strategies. To provide molecular tools for examining these questions, we isolated microsatellite loci through 454 pyrosequencing of a repeat-enriched A. vulgare genomic library. We selected 14 markers and developed three polymorphic microsatellite multiplex kits. We tested the kits on two A. vulgare natural populations and found high genetic variation, thereby making it possible to investigate the impact of Wolbachia endosymbionts on A. vulgare nuclear variation at unprecedented resolution. In addition, we tested the transferability of these kits by cross-species amplification in five other terrestrial isopod species harboring Wolbachia endosymbionts. The microsatellite loci showed good transferability in particular in Armadillidium nasatum and Chaetophiloscia elongata, for which these markers represent promising tools for future genetic studies. PMID:24098543

  13. Isolation and characterization of microsatellite loci for the isopod crustacean Armadillidium vulgare and transferability in terrestrial isopods.

    PubMed

    Giraud, Isabelle; Valette, Victorien; Bech, Nicolas; Grandjean, Frédéric; Cordaux, Richard

    2013-01-01

    Armadillidium vulgare is a terrestrial isopod (Crustacea, Oniscidea) which harbors Wolbachia bacterial endosymbionts. A. vulgare is the major model for the study of Wolbachia-mediated feminization of genetic males in crustaceans. As a consequence of their impact on host sex determination mechanisms, Wolbachia endosymbionts are thought to significantly influence A. vulgare evolution on various grounds, including population genetic structure, diversity and reproduction strategies. To provide molecular tools for examining these questions, we isolated microsatellite loci through 454 pyrosequencing of a repeat-enriched A. vulgare genomic library. We selected 14 markers and developed three polymorphic microsatellite multiplex kits. We tested the kits on two A. vulgare natural populations and found high genetic variation, thereby making it possible to investigate the impact of Wolbachia endosymbionts on A. vulgare nuclear variation at unprecedented resolution. In addition, we tested the transferability of these kits by cross-species amplification in five other terrestrial isopod species harboring Wolbachia endosymbionts. The microsatellite loci showed good transferability in particular in Armadillidium nasatum and Chaetophiloscia elongata, for which these markers represent promising tools for future genetic studies. PMID:24098543

  14. Great Lakes Beach Health

    USGS Multimedia Gallery

    As schools close for the year and summer weather beckons, many recreationalists head to the Great Lakes' public beaches. However, these coastal areas can become contaminated with disease-causing bacteria that threaten public health, disrupt water recreation, and pay a toll on the Great Lakes economi...

  15. Reference values for feeding parameters of isopods (Porcellio scaber, Isopoda, Crustacea)

    PubMed Central

    Drobne, Damjana; Drobne, Samo

    2014-01-01

    Abstract The advantage of using terrestrial isopods in toxicity studies is that a battery of parameters can be tested at different levels of biological complexity. Feeding parameters for example link organism level response to potential ecological consequences but a problem with using feeding parameters in toxicity tests with terrestrial isopods is their high variability. The aim of our study was to set benchmark values for feeding parameters for isopod Porcellio scaber (Isopoda, Crustacea) in laboratory-controlled experiments. In the work presented here, the daily feeding rate of the central 50% of the control population of Porcellio scaber and a correlation between feeding rate and isopod weight were set. Values outside these ranges need additional evaluation to increase the relevance of test outcomes. We suggest using benchmark values for feeding parameters as well as the coefficient of variation (a) to identify animals with altered feeding parameters with respect to controls, and (b) to assess the data quality in each experiment. PMID:25561844

  16. Terrestrial isopods -- a good choice for toxicity testing of pollutants in the terrestrial environment

    SciTech Connect

    Drobne, D.

    1997-06-01

    Terrestrial isopods are suitable invertebrates for testing the relative toxicities of chemicals present in the terrestrial environment. Terrestrial isopods respond in numerous ways to elevated concentrations of chemicals in their food, but only a few of these responses can be used as toxicological endpoints. The most suitable are changes in reproduction, food consumption, moult cycle duration, and structure of the digestive glands. These responses are able to provide accurate indications of sublethal toxicity. Toxicity tests with terrestrial isopods could be much more reliable through the use of positive controls. A positive control with a reference toxicant could also be supplemented by a reference endpoint. The most suitable reference endpoint is change of food consumption rate. Toxicity testing with terrestrial isopods is a very promising method for fast, routine, and inexpensive laboratory determination of the relative toxicities of chemicals in the terrestrial environment.

  17. Shoreline relaxation at pocket beaches

    NASA Astrophysics Data System (ADS)

    Turki, Imen; Medina, Raul; Kakeh, Nabil; González, Mauricio

    2015-09-01

    A new physical concept of relaxation time is introduced in this research as the time required for the beach to dissipate its initial perturbation. This concept is investigated using a simple beach-evolution model of shoreline rotation at pocket beaches, based on the assumption that the instantaneous change of the shoreline plan-view shape depends on the long-term equilibrium plan-view shape. The expression of relaxation time is developed function of the energy conditions and the physical characteristics of the beach; it increases at longer beaches having coarse sediments and experiencing low-energy conditions. The relaxation time, calculated by the developed model, is validated by the shoreline observations extracted from video images at two artificially embayed beaches of Barcelona (NW Mediterranean) suffering from perturbations of sand movement and a nourishment project. This finding is promising to estimate the shoreline response and useful to improve our understanding of the dynamic of pocket beaches and their stability.

  18. Global Diversity of Marine Isopods (Except Asellota and Crustacean Symbionts)

    PubMed Central

    Poore, Gary C. B.; Bruce, Niel L.

    2012-01-01

    The crustacean order Isopoda (excluding Asellota, crustacean symbionts and freshwater taxa) comprise 3154 described marine species in 379 genera in 37 families according to the WoRMS catalogue. The history of taxonomic discovery over the last two centuries is reviewed. Although a well defined order with the Peracarida, their relationship to other orders is not yet resolved but systematics of the major subordinal taxa is relatively well understood. Isopods range in size from less than 1 mm to Bathynomus giganteus at 365 mm long. They inhabit all marine habitats down to 7280 m depth but with few doubtful exceptions species have restricted biogeographic and bathymetric ranges. Four feeding categories are recognised as much on the basis of anecdotal evidence as hard data: detritus feeders and browsers, carnivores, parasites, and filter feeders. Notable among these are the Cymothooidea that range from predators and scavengers to external blood-sucking micropredators and parasites. Isopods brood 10–1600 eggs depending on individual species. Strong sexual dimorphism is characteristic of several families, notably in Gnathiidae where sessile males live with a harem of females while juvenile praniza stages are ectoparasites of fish. Protandry is known in Cymothoidae and protogyny in Anthuroidea. Some Paranthuridae are neotenous. About half of all coastal, shelf and upper bathyal species have been recorded in the MEOW temperate realms, 40% in tropical regions and the remainder in polar seas. The greatest concentration of temperate species is in Australasia; more have been recorded from temperate North Pacific than the North Atlantic. Of tropical regions, the Central Indo-Pacific is home to more species any other region. Isopods are decidedly asymmetrical latitudinally with 1.35 times as many species in temperate Southern Hemisphere than the temperate North Atlantic and northern Pacific, and almost four times as many Antarctic as Arctic species. More species are known from the bathyal and abyssal Antarctic than Arctic GOODS provinces, and more from the larger Pacific than Atlantic oceans. Two areas with many species known are the New Zealand-Kermadec and the Northern North Pacific provinces. Deep hard substrates such as found on seamounts and the slopes are underrepresented in samples. This, the documented numbers of undescribed species in recent collections and probable cryptic species suggest a large as yet undocumented fauna, potentially an order of magnitude greater than presently known. PMID:22952700

  19. Global diversity of marine isopods (except Asellota and crustacean symbionts).

    PubMed

    Poore, Gary C B; Bruce, Niel L

    2012-01-01

    The crustacean order Isopoda (excluding Asellota, crustacean symbionts and freshwater taxa) comprise 3154 described marine species in 379 genera in 37 families according to the WoRMS catalogue. The history of taxonomic discovery over the last two centuries is reviewed. Although a well defined order with the Peracarida, their relationship to other orders is not yet resolved but systematics of the major subordinal taxa is relatively well understood. Isopods range in size from less than 1 mm to Bathynomus giganteus at 365 mm long. They inhabit all marine habitats down to 7280 m depth but with few doubtful exceptions species have restricted biogeographic and bathymetric ranges. Four feeding categories are recognised as much on the basis of anecdotal evidence as hard data: detritus feeders and browsers, carnivores, parasites, and filter feeders. Notable among these are the Cymothooidea that range from predators and scavengers to external blood-sucking micropredators and parasites. Isopods brood 10-1600 eggs depending on individual species. Strong sexual dimorphism is characteristic of several families, notably in Gnathiidae where sessile males live with a harem of females while juvenile praniza stages are ectoparasites of fish. Protandry is known in Cymothoidae and protogyny in Anthuroidea. Some Paranthuridae are neotenous. About half of all coastal, shelf and upper bathyal species have been recorded in the MEOW temperate realms, 40% in tropical regions and the remainder in polar seas. The greatest concentration of temperate species is in Australasia; more have been recorded from temperate North Pacific than the North Atlantic. Of tropical regions, the Central Indo-Pacific is home to more species any other region. Isopods are decidedly asymmetrical latitudinally with 1.35 times as many species in temperate Southern Hemisphere than the temperate North Atlantic and northern Pacific, and almost four times as many Antarctic as Arctic species. More species are known from the bathyal and abyssal Antarctic than Arctic GOODS provinces, and more from the larger Pacific than Atlantic oceans. Two areas with many species known are the New Zealand-Kermadec and the Northern North Pacific provinces. Deep hard substrates such as found on seamounts and the slopes are underrepresented in samples. This, the documented numbers of undescribed species in recent collections and probable cryptic species suggest a large as yet undocumented fauna, potentially an order of magnitude greater than presently known. PMID:22952700

  20. Contemporary Parallel Diversification, Antipredator Adaptations and Phenotypic Integration in an Aquatic Isopod

    PubMed Central

    Eroukhmanoff, Fabrice; Svensson, Erik I.

    2009-01-01

    It is increasingly being recognized that predation can be a strong diversifying agent promoting ecological divergence. Adaptations against different predatory regimes can emerge over short periods of time and include many different traits. We studied antipredator adaptations in two ecotypes of an isopod (Asellus aquaticus) that have, diverged in parallel in two Swedish lakes over the last two decades. We quantified differences in escape speed, morphology and behavior for isopods from different ecotypes present in these lakes. Isopods from the source habitat (reed) coexist with mainly invertebrate predators. They are more stream-profiled and have higher escape speeds than isopods in the newly colonized stonewort habitat, which has higher density of fish predators. Stonewort isopods also show more cautious behaviors and had higher levels of phenotypic integration between coloration and morphological traits than the reed isopods. Colonization of a novel habitat with a different predation regime has thus strengthened the correlations between pigmentation and morphology and weakened escape performance. The strong signature of parallelism for these phenotypic traits indicates that divergence is likely to be adaptive and is likely to have been driven by differences in predatory regimes. Furthermore, our results indicate that physical performance, behavior and morphology can change rapidly and in concert as new habitats are colonized. PMID:19587791

  1. Ommochrome genesis in an albino strain of a terrestrial isopod.

    PubMed

    Hasegawa, Y; Negishi, S; Naito, J; Ikeda, R; Hasegawa, H; Nagamura, Y; Ishiguro, I

    1999-01-01

    The contents of tryptophan (Trp) metabolites and the activities of the enzymes involved in ommochrome biosynthesis were measured in an albino strain of a terrestrial isopod Armadillidium vulgare. There was little difference between the Trp content in the albino mutant and that in the wild type, although the contents of 3-hydroxykynurenine (3-OH-Kyn), 3-hydroxyanthranilic acid (3-OH-AA) and xanthommatin in the albino were significantly lower than those in the wild type. Tryptophan 2,3-dioxygenase (TDO) activity in the albino was extremely low, while the activities of Kyn-3-hydroxylase and kynureninase did not differ significantly between the two phenotypes. The extremely low activity of TDO is probably one of main reasons why almost no ommochrome pigment is produced in the albino mutant. PMID:10721113

  2. Traits underpinning desiccation resistance explain distribution patterns of terrestrial isopods.

    PubMed

    Dias, André T C; Krab, Eveline J; Mariën, Janine; Zimmer, Martin; Cornelissen, Johannes H C; Ellers, Jacintha; Wardle, David A; Berg, Matty P

    2013-07-01

    Predicted changes in soil water availability regimes with climate and land-use change will impact the community of functionally important soil organisms, such as macro-detritivores. Identifying and quantifying the functional traits that underlie interspecific differences in desiccation resistance will enhance our ability to predict both macro-detritivore community responses to changing water regimes and the consequences of the associated species shifts for organic matter turnover. Using path analysis, we tested (1) how interspecific differences in desiccation resistance among 22 northwestern European terrestrial isopod species could be explained by three underlying traits measured under standard laboratory conditions, namely, body ventral surface area, water loss rate and fatal water loss; (2) whether these relationships were robust to contrasting experimental conditions and to the phylogenetic relatedness effects being excluded; (3) whether desiccation resistance and hypothesized underlying traits could explain species distribution patterns in relation to site water availability. Water loss rate and (secondarily) fatal water loss together explained 90% of the interspecific variation in desiccation resistance. Our path model indicated that body surface area affects desiccation resistance only indirectly via changes in water loss rate. Our results also show that soil moisture determines isopod species distributions by filtering them according to traits underpinning desiccation resistance. These findings reveal that it is possible to use functional traits measured under standard conditions to predict soil biota responses to water availability in the field over broad spatial scales. Taken together, our results demonstrate an increasing need to generate mechanistic models to predict the effect of global changes on functionally important organisms. PMID:23224790

  3. Beach ridges and prograded beach deposits as palaeoenvironment records

    NASA Astrophysics Data System (ADS)

    Tamura, Toru

    2012-09-01

    Beach ridges are landforms commonly developed on prograded coasts with beach shorelines. A sequence of beach ridges, coupled with their subsurface deposits, can be regarded as a time series of coastal evolution. Methodological advances in field surveying and chronology applicable to beach ridges have led to detailed palaeoenvironmental reconstructions to be derived from such sequences. This paper reconsiders the basic aspects of beach ridges and deposits, which need to be properly understood for their comprehensive interpretation in a palaeo-environmental context. It also reviews case studies in which beach-ridge sequences have been used to unveil past sea-level history, catastrophic events, and climate changes. Proposed formative processes of beach ridges include: 1) progradation of sandy beach and berm formations in relation to fairweather waves, coupled with aeolian foredune accumulation; 2) building of gravel ridges by storm waves; 3) welding of longshore bars. Beach-ridge formation through sea-level oscillation is thought to be questionable and caution is suggested for this process when undertaking palaeoenvironmental reconstruction. Beach deposit stratification is known to dip either landwards or seawards, but landward dips are uncommon. Seaward dipping stratification is formed in relation to beachface progradation, and is usually dissected in places by erosion surfaces resulting from episodic beach retreat. The boundary between the foreshore and the underlying shoreface is well defined only in the case that longshore bars lead to complex bedding structure relative to that of the foreshore. Reliable chronology of beach ridges can be determined by radiocarbon and optically-stimulated luminescence (OSL) dating. Radiocarbon dating of articulated shells, which are considered not to be extensively reworked, provides robust results, but OSL dating is more useful as it enables direct dating of sediment grains. It is noted that there are restrictions in chronological resolution and continuity inherent to beach ridge and beach deposits. The plan-view geomorphic expression of beach ridges typically consists of ridge sets with multi-decadal intervals, whereas their internal sedimentary structures define shorter time scales. Records of beach sedimentation and erosion are likely to be reworked by episodic high-magnitude beach retreat, and the resultant record of the net progradation is likely to be sporadic and discontinuous. The height of sandy beach ridges is often variable due to differing degrees of aeolian sand accumulation, and they are thus not used as sea-level indicators unless purely wave-built. Gravel ridge height is a relatively reliable indicator of sea level, but can vary in response to storminess fluctuations. Subsurface sediment facies boundaries are preferred as sea-level indicators, and those proposed include: boundaries of aeolian/beach, foreshore/shoreface, and upper/lower shorefaces. Catastrophic events are expressed in both erosional and depositional records. Erosion surfaces, or scarp imprints, revealed in a cross section of beach deposits, indicate storm or tsunami events. However, erosional events are likely to rework previous records of sedimentation and even other erosional events, and thus the apparent history decoded from the resultant deposits tends to be biased. Several attempts for estimating the frequency and intensity of prehistoric cyclones rely on assumed relationships between the level of coarse sand beach ridges and cyclone inundation. The formative process of coarse sand ridges remains uncertain and needs to be clarified, as it constitutes the fundamental basis of these attempts. The growth rates of beach-ridge systems are expected to reflect fluctuations in river sediment discharge to the coast and in aeolian sand flux due to onshore winds, both of which are affected by climate change. Assessment of the growth rate is potentially improved by ground-penetrating radar survey of subsurface structure and by detailed chronology. Orientation of beach ridges reflects long-term trends in wave dir

  4. Sand hazards on tourist beaches.

    PubMed

    Heggie, Travis W

    2013-01-01

    Visiting the beach is a popular tourist activity worldwide. Unfortunately, the beach environment is abundant with hazards and potential danger to the unsuspecting tourist. While the traditional focus of beach safety has been water safety oriented, there is growing concern about the risks posed by the sand environment on beaches. This study reports on the death and near death experience of eight tourists in the collapse of sand holes, sand dunes, and sand tunnels. Each incident occurred suddenly and the complete burial in sand directly contributed to the victims injury or death in each case report. PMID:23290717

  5. Widespread atypical mitochondrial DNA structure in isopods (Crustacea, Peracarida) related to a constitutive heteroplasmy in terrestrial species.

    PubMed

    Doublet, Vincent; Raimond, Roland; Grandjean, Frédéric; Lafitte, Alexandra; Souty-Grosset, Catherine; Marcadé, Isabelle

    2012-03-01

    Metazoan mitochondrial DNA (mtDNA) is generally composed of circular monomeric molecules. However, a few exceptions do exist and among them two terrestrial isopods Armadillidium vulgare and Porcellionides pruinosus have an atypical mtDNA composed of linear monomers associated with circular "head-to-head" dimers: a very unusual structure for animal mtDNA genome. To assess the distribution of this atypical mtDNA among isopods, we performed RFLP and Southern blot analyses on mtDNA of 16 terrestrial (Oniscidea family) and two aquatic isopod species: the marine Sphaeroma serratum (suborder Flabellifera, sister group of Oniscidea) and the freshwater Asellus aquaticus (Asellota, early derived taxon of isopod). The atypical mtDNA structure was observed in 15 terrestrial isopod species and A. aquaticus, suggesting a wide distribution of atypical mtDNA among isopods. However, a typical metazoan mtDNA structure was detected in the marine isopod S. serratum and the Oniscidea Ligia oceanica . Our results suggest two possible scenarios: an early origin of the atypical mtDNA in isopods followed by reversion to the typical ancestral mtDNA structure for several species, or a convergent appearance of the atypical mtDNA structure in two isopod suborders. We compare this distribution of the atypical mtDNA structure with the presence of a heteroplasmy also observed in the mtDNA of several terrestrial isopod species. We discuss if this transmitted heteroplasmy is vectored by the atypical mtDNA and its impact on the maintenance of the atypical mtDNA in isopods. PMID:22376074

  6. Benign effect of the fish parasitic isopod Ceratothoa cf. imbricata on Selenotoca multifasciata (Scatophagidae) from Australia.

    PubMed

    Carrassón, M; Cribb, T H

    2014-08-11

    The tongue-biter cymothoid isopod Ceratothoa cf. imbricata is nearly ubiquitous in buccal cavities of the banded scat Selenotoca multifasciata (Scatophagidae) from Waterloo Bay, south-east Queensland. To test whether infestation affects fish growth or condition significantly, we explored parasitism and condition in 122 S. multifasciata specimens. The internal area of the buccal cavity and that occupied by ovigerous female isopods were measured, allowing the relative proportion of free internal area of the buccal cavity (PFIAO) to be calculated. Of 122 fish, 119 (97.5%) were infected; 35.3% had large female isopods, the remaining infections comprised much smaller mancae, juveniles and adult males. Mean intensity of infection was significantly correlated with fish total length (TL). In some fish, the female isopod occupied up to 80% of the buccal cavity area. There was little evidence of attachment damage in the buccal cavity; only 9 of 43 hosts analysed had restricted damage to the tissues at the points of attachment of the female isopod. Condition factor, food intensity index and stomach weight did not differ between fish with and without female C. cf. imbricata. The relative proportion of free internal area of the buccal cavity with respect to the fish total length (PFIAO/TL2 ratio) of fish infected with females correlated with food intensity and condition factor. Although the correlation was significant, the actual effect was not large because more than 70% of these 2 indices was not explained by the PFIAO/TL2 ratio (r2 < 0.3 in both cases). Despite the dramatic appearance of infestations and the high prevalence of C. cf. imbricata in the population, the near-absence of pathological alterations and the limited effect of the isopod on the condition indices and food intensity suggest that this isopod is relatively benign for S. multifasciata. PMID:25114041

  7. Getting Aquainted with Beaches and Coasts.

    ERIC Educational Resources Information Center

    DeWall, Allan E.

    1980-01-01

    Explains how a shoreline is formed and how it changes, and why its changes do not always coincide with human plans. Subjects discussed include beaches, beach processes, inlets and beaches, and a marine glossary. (Author/DS)

  8. Sea-land transitions in isopods: pattern of symbiont distribution in two species of intertidal isopods Ligia pallasii and Ligia occidentalis in the Eastern Pacific.

    PubMed

    Eberl, Renate

    2010-07-01

    Studies of microbial associations of intertidal isopods in the primitive genus Ligia (Oniscidea, Isopoda) can help our understanding of the formation of symbioses during sea-land transitions, as terrestrial Oniscidean isopods have previously been found to house symbionts in their hepatopancreas. Ligia pallasii and Ligia occidentalis co-occur in the high intertidal zone along the Eastern Pacific with a large zone of range overlap and both species showing patchy distributions. In 16S rRNA clone libraries mycoplasma-like bacteria (Firmicutes), related to symbionts described from terrestrial isopods, were the most common bacteria present in both host species. There was greater overall microbial diversity in Ligia pallasii compared with L. occidentalis. Populations of both Ligia species along an extensive area of the eastern Pacific coastline were screened for the presence of mycoplasma-like symbionts with symbiont-specific primers. Symbionts were present in all host populations from both species but not in all individuals. Phylogenetically, symbionts of intertidal isopods cluster together. Host habitat, in addition to host phylogeny appears to influence the phylogenetic relation of symbionts. PMID:20730112

  9. Sea-land transitions in isopods: pattern of symbiont distribution in two species of intertidal isopods Ligia pallasii and Ligia occidentalis in the Eastern Pacific

    PubMed Central

    2010-01-01

    Studies of microbial associations of intertidal isopods in the primitive genus Ligia (Oniscidea, Isopoda) can help our understanding of the formation of symbioses during sea-land transitions, as terrestrial Oniscidean isopods have previously been found to house symbionts in their hepatopancreas. Ligia pallasii and Ligia occidentalis co-occur in the high intertidal zone along the Eastern Pacific with a large zone of range overlap and both species showing patchy distributions. In 16S rRNA clone libraries mycoplasma-like bacteria (Firmicutes), related to symbionts described from terrestrial isopods, were the most common bacteria present in both host species. There was greater overall microbial diversity in Ligia pallasii compared with L. occidentalis. Populations of both Ligia species along an extensive area of the eastern Pacific coastline were screened for the presence of mycoplasma-like symbionts with symbiont-specific primers. Symbionts were present in all host populations from both species but not in all individuals. Phylogenetically, symbionts of intertidal isopods cluster together. Host habitat, in addition to host phylogeny appears to influence the phylogenetic relation of symbionts. PMID:20730112

  10. Active and passive migration in boring isopods Limnoria spp. (Crustacea, Peracarida) from kelp holdfasts

    NASA Astrophysics Data System (ADS)

    Miranda, Leonardo; Thiel, Martin

    2008-10-01

    Many boring isopods inhabit positively buoyant substrata (wood and algae), which float after detachment, permitting passive migration of inhabitants. Based on observations from previous studies, it was hypothesized that juvenile, subadult and male isopods migrate actively, and will rapidly abandon substrata after detachment. In contrast, reproductive females and small offspring were predicted to remain in floating substrata and thus have a high probability to disperse passively via rafting. In order to test this hypothesis, a colonization and an emigration experiment were conducted with giant kelp ( Macrocystis integrifolia), the holdfasts of which are inhabited by boring isopods from the genus Limnoria. A survey of benthic substrata in the kelp forest confirmed that limnoriids inhabited the holdfasts and did not occur in holdfast-free samples. Results of the colonization experiment showed that all life history stages of the boring isopods immigrated into young, largely uncolonized holdfasts, and after 16 weeks all holdfasts were densely colonized. In the emigration experiment, all life history stages of the isopods rapidly abandoned the detached holdfasts — already 5 min after detachment only few individuals remained in the floating holdfasts. After this initial rapid emigration of isopods, little changes in isopod abundance occurred during the following 24 h, and at the end of the experiment some individuals of all life history stages still remained in the holdfasts. These results indicate that all life history stages of Limnoria participate in both active migration and passive dispersal. It is discussed that storm-related dynamics within kelp forests may contribute to intense mixing of local populations of these burrow-dwelling isopods, and that most immigrants to young holdfasts probably are individuals emigrating from old holdfasts detached during storm events. The fact that some individuals of all life history stages and both sexes remain in floating holdfasts suggests that limnoriids could successfully reproduce during rafting journeys in floating kelp, facilitating long-distance dispersal. We propose that the coexistence of different modes of dispersal (short distance local migrations and long-distance regional dispersal) within these kelp-dwelling isopods might be advantageous in an environment where unpredictable El Niño events can cause extinction of local kelp forests.

  11. Variation of the Beach Profile, Ocean Beach, San Francisco, California

    NASA Astrophysics Data System (ADS)

    Hansen, J. E.; Ho, T.; Li, A.; Perez, A.; Wong, Y.; Bissell, M.

    2006-12-01

    Ocean Beach is a 7-km-long stretch of beach that is the western boundary of the city of San Francisco with the Pacific Ocean. This beach is exposed to large winter waves produced in the North Pacific and smaller summer waves from both the North and South Pacific. Recent decades have seen an increased rate of erosion at the south end of the beach that has led to the partial collapse of a parking lot, and continued erosion threatens both public and private infrastructure. To gain an understanding of the variation in beach profiles we established six cross-shore profiles approximately 1 km apart. Each profile represents a part of the beach that experiences different wave conditions, caused by refraction across the San Francisco Bar, and thus has a different morphologic response to offshore sea conditions. The six sub-aerial profiles were measured using a total station one week apart in August 2006. All profiles increased in elevation and five of the six profiles showed the early formation or continued growth of berms. The same profiles will be re-analyzed in the autumn to determine further change, and compared to data collected by a 2004 SF-ROCKS group that also studied Ocean Beach. We will relate beach profile change to wave conditions measured at an offshore buoy to determine what wave conditions cause profile accretion or erosion. The results of this study will shed light on the processes occurring at Ocean Beach and will help us to understand why the south end of the beach is eroding.

  12. Historical influences on deep-sea isopod diversity in the Atlantic Ocean

    NASA Astrophysics Data System (ADS)

    Wilson, George D. F.

    1998-01-01

    Most isopod crustaceans in the North Atlantic deep sea belong to the suborder Asellota. In contrast, South Atlantic isopod faunas have a significant component of flabelliferan isopods, a phylogenetic clade that contains suborders derived evolutionarily later than the Asellota. The flabelliferans decrease diversity from shallow water to deep water and on a south-to-north latitudinal gradient. Although many asellote families are endemic to the deep sea, none of the flabelliferan families appear to have evolved in the abyss. Recent colonisations of the deep sea, which may have been limited to the southern hemisphere by oceanographic conditions, have significant consequences for observed regional diversities of some taxa. Instability in oceanographic conditions owing to glaciation and benthic storms may have further limited benthic species richness of the North Atlantic deep-sea benthos.

  13. Sound production in the aquatic isopod Cymodoce japonica (Crustacea: Peracarida).

    PubMed

    Nakamachi, Takeru; Ishida, Hideki; Hirohashi, Noritaka

    2015-10-01

    A vast variety of acoustic behaviors and mechanisms occur in arthropods. Sound production, in particular, in insects and decapod crustaceans has been well documented. However, except for a brief, anecdotal statement, there has been no report on the acoustic behavior of aquatic isopods. We present the first empirical evidence in aquatic Isopoda that males of Cymodoce japonica produce sound by stridulation, or the rubbing together of body parts. Sound production was associated with tail-lifting behavior, suggesting that stridulation occurs on thoracic and/or abdominal somites. Acoustic analysis revealed that syllable length was similar throughout the stridulation, at a mode of 2500-3000 Hz. With a scanning electron microscope, we identified file-like structures on the inner surface of the dorsal exoskeleton. Each file consisted of 188 ± 11.1 ridges at about 0.5 ?m intervals; the theoretical frequency (number of ridges per syllable length) was estimated to be 2208-3646 Hz. This finding suggests that the stridulation sounds arose from these structures. Laboratory observations show that stridulation may play a role in the threatening of other males in the context of territorial and/or reproductive competitions. PMID:26504157

  14. Impact of micropredatory gnathiid isopods on young coral reef fishes

    NASA Astrophysics Data System (ADS)

    Grutter, A. S.; Pickering, J. L.; McCallum, H.; McCormick, M. I.

    2008-09-01

    The ecological role of parasites in the early life-history stages of coral reef fish, and whether this varies between fish with and without a pelagic phase, was investigated. The susceptibility to, and effect of reef-based micropredatory gnathiid isopods on larval, recently settled, and juvenile fishes was tested using two damselfishes (Pomacentridae): Neopomacentrus azysron, which has pelagic larvae, and Acanthochromis polyacanthus, which does not. When larval and recently settled stages of N. azysron and very young A. polyacanthus juveniles (smaller than larval N. azysron) were exposed to one or three gnathiids, the proportion of infections did not vary significantly among the three host types or between the number of gnathiids to which the fish were exposed. The overall infection was 35%. Mortality, however, differed among the three gnathiid-exposed host types with most deaths occurring in larval N. azysron; no mortalities occurred for recently settled N. azysron exposed to one or three gnathiids, and A. polyacanthus exposed to one gnathiid. Mortality did not differ significantly between larval N. azysron and A. polyacanthus juveniles, failing to provide support for the hypothesis that reef-based A. polyacanthus juveniles are better adapted to gnathiid attack than fish with a pelagic phase. The study suggests that settling on the reef exposes young fish to potentially deadly micropredators. This supports the idea that the pelagic phase may allow young fish to avoid reef-based parasites.

  15. Surface characteristics of isopod digestive gland epithelium studied by SEM.

    PubMed

    Millaku, Agron; Leser, Vladka; Drobne, Damjana; Godec, Matjaz; Torkar, Matjaz; Jenko, Monika; Milani, Marziale; Tatti, Francesco

    2010-05-01

    The structure of the digestive gland epithelium of a terrestrial isopod Porcellio scaber has been investigated by conventional scanning electron microscopy (SEM), focused ion beam-scanning electron microscopy (FIB/SEM), and light microscopy in order to provide evidence on morphology of the gland epithelial surface in animals from a stock culture. We investigated the shape of cells, extrusion of lipid droplets, shape and distribution of microvilli, and the presence of bacteria on the cell surface. A total of 22 animals were investigated and we found some variability in the appearance of the gland epithelial surface. Seventeen of the animals had dome-shaped digestive gland "normal" epithelial cells, which were densely and homogeneously covered by microvilli and varying proportions of which extruded lipid droplets. On the surface of microvilli we routinely observed sparsely distributed bacteria of different shapes. Five of the 22 animals had "abnormal" epithelial cells with a significantly altered shape. In three of these animals, the cells were much smaller, partly or completely flat or sometimes pyramid-like. A thick layer of bacteria was detected on the microvillous border, and in places, the shape and size of microvilli were altered. In two animals, hypertrophic cells containing large vacuoles were observed indicating a characteristic intracellular infection. The potential of SEM in morphological investigations of epithelial surfaces is discussed. PMID:20155290

  16. Photosensitive neurogenic heart of the isopod crustacean Ligia exotica

    PubMed Central

    Miyamoto, Hiroshi; Horiguchi, Hiroko; Hariyama, Takahiko; Takano, Satoshi; Yamagishi, Hiroshi

    2006-01-01

    The heart of animals is regulated through the central nervous system in response to external sensory stimuli. We found, however, that the adult neurogenic heart of the isopod crustacean Ligia exotica has photosensitivity. The beat frequency of the isolated heart decreased in response to a light stimulus. Magnitude of the response was stimulus intensity dependent and the heartbeat frequency decreased to less than 80% of the dark value during illumination of the white light with an intensity of 6.0?mW?cm?2. The spectral sensitivity curve of the heart photoresponse peaked at a wavelength around 520?nm. In response to 530?nm monochromatic light, the relationship between light intensity and response magnitude was linear and the threshold intensity was 7.26×1012?quanta?cm?2?s?1. Bursting activity of the cardiac ganglion, which is located in the heart and acts as the cardiac pacemaker deceased in frequency in response to illumination by white light. This fact suggests that the heart photoresponse of L. exotica results from the photosensitivity of the cardiac ganglion neurons. The photoresponse of the heart therefore contributes to regulation of cardiac output in addition to other regulatory systems. PMID:16959646

  17. Photosensitive neurogenic heart of the isopod crustacean Ligia exotica.

    PubMed

    Miyamoto, Hiroshi; Horiguchi, Hiroko; Hariyama, Takahiko; Takano, Satoshi; Yamagishi, Hiroshi

    2006-10-01

    The heart of animals is regulated through the central nervous system in response to external sensory stimuli. We found, however, that the adult neurogenic heart of the isopod crustacean Ligia exotica has photosensitivity. The beat frequency of the isolated heart decreased in response to a light stimulus. Magnitude of the response was stimulus intensity dependent and the heartbeat frequency decreased to less than 80% of the dark value during illumination of the white light with an intensity of 6.0 mW cm-2. The spectral sensitivity curve of the heart photoresponse peaked at a wavelength around 520 nm. In response to 530 nm monochromatic light, the relationship between light intensity and response magnitude was linear and the threshold intensity was 7.26 x 1012 quanta cm-2 s-1. Bursting activity of the cardiac ganglion, which is located in the heart and acts as the cardiac pacemaker deceased in frequency in response to illumination by white light. This fact suggests that the heart photoresponse of L. exotica results from the photosensitivity of the cardiac ganglion neurons. The photoresponse of the heart therefore contributes to regulation of cardiac output in addition to other regulatory systems. PMID:16959646

  18. Uptake and elimination of benzo[a]pyrene in the terrestrial isopod Porcellio scaber.

    PubMed

    van Brummelen, T C; van Straalen, N M

    1996-08-01

    In isopods from contaminated sites relatively low levels of high molecular weight polycyclic aromatic hydrocarbons (PAHs) have been observed, which may be caused by either a low bioavailability or a high elimination rate. To shed light on this, the uptake and elimination rates of benzo[a]pyrene were estimated for the isopod Porcellio scaber. The isopod was fed contaminated food (100 microg benzo[a]pyrene/g dwt) for seven weeks followed by four weeks of untreated food. The hindguts of the animals were removed prior to analysis to exclude food material from the body. Benzo[a]pyrene concentrations were log-normally distributed among the individuals. The high inter-individual variation in benzo[a]pyrene content could not be explained from differences in sex, the estimated amount of food in the hindgut, or the body weight. A one-compartment model fitted to the isopod concentrations estimated an assimilation rate of 2.9 microg benzo[a]pyrene/g dwt day, an elimination rate constant of 1.1/day and an equilibrium concentration of 2.5 microg benzo[a]pyrene/g dwt. According to the model 68% of the isopod population had an equilibrium concentration between 1.0 and 7.2 microg benzo[a]pyrene/g dwt day with a benzo[a]pyrene half-life ranging between 0.4 and 1.3 days. The assimilation efficiency was estimated at 20 to 40% of the ingested benzo[a]pyrene. The tissue distribution of benzo[a]pyrene was investigated in a separate experiment. Trace levels of benzo[a]pyrene were detected in haemolymph samples, demonstrating absorption and transport of the compound in the isopod. It is concluded that dietary benzo[a]pyrene is available for uptake to the isopod and that low residues of the compound observed in field isopods are the result of a high elimination rate rather than a reduced bioavailability. As PAHs from soil appear to be available to soil invertebrates, the widespread contamination of the soil from atmospheric emissions is of some concern, especially since the observed elimination may be linked to metabolic activation of PAHs. PMID:8781081

  19. Concepts in gravel beach dynamics

    NASA Astrophysics Data System (ADS)

    Buscombe, Daniel; Masselink, Gerhard

    2006-11-01

    The dominant processes in gravel beach dynamics are reviewed, highlighting some common themes which unify the various components of the gravel beach system, the repercussions of which impart on how gravel beach dynamics might be understood conceptually. In particular, gravel beach dynamics are thought to be highly dependent on the temporal and spatial variation in grain size, and the continual adjustments made by an active beach step, both of which act not only as the expression of changing morphodynamic conditions, but also as a controlling influence. Morphodynamics, the notion that the exchanges on beaches between the hydrodynamics, sediment transport, and morphological change takes the form of reciprocal relationships which are mediated through feedback mechanisms (in such a way that they cannot be thought of or studied independently) is not a new one. Yet it appears that for the gravel beach, morphodynamics must be re-defined to describe conditions where variations in sediment size are thought to deserve parity, rather than as merely a sequent entity or boundary condition. 'Morpho-sedimentary-dynamics' is a phrase coined to intuit such cause and effect, detailing the co-evolution of morphology, hydro-hydraulics and sediment properties whilst acknowledging causative pluralism, feedbacks and multiplier effects. This is the recommended conceptual framework within which to crystallise thought and organise further research for the gravel beach. Essentially, it increases the minimum number of parameters needed to describe the state of the gravel beach as a physical system. Therefore, it is advised that simplicity will be most expedient in our future modelling efforts, if complexity is to be adequately encapsulated.

  20. Substrate selection and seasonal variation in abundance and size composition of isopod Lirceus fontinalis in Ontario streams, Canada

    NASA Astrophysics Data System (ADS)

    Zhao, Xiaoxia; Fox, Michael G.; Lasenby, David C.; Armit, Alexis C.; Kothawala, Dolly N.

    2007-04-01

    The abundance and size composition of stream isopods Lirceus fontinalis were investigated from April 2001 to August 2002 in 3 streams in southern Ontario, Canada. Effects of current speed was released from the analysis by choosing slow flowing water. The effects of substrate, season and water depth on the abundance, distribution and size composition of the isopods were analyzed. It was found that substrate and season influence isopods the most. The rocky substrate with attached filamentous macro-algae contains an isopod abundance 7.05 times that of bare rock substrate and 14.6 times that of fine-sand and mud substrate. There was a large variation with respect to seasonality in both abundance and size composition of the isopods, with the highest abundance occurring in summer and the lowest in winter and spring; individual isopods also tend to be larger in the winter and spring. In all substrates, shallow areas tend to support higher densities of isopods than deeper areas.

  1. Ecological Relationships Between the Valviferan Isopod Edotia doellojuradoiGiambiagi, 1925, and its Host Mytilus edulis chilensisin the Falkland Islands

    NASA Astrophysics Data System (ADS)

    Gray, A. P.; Richardson, C. A.; Seed, R.

    1997-02-01

    A hitherto undescribed association between the valviferan isopod, Edotia doellojuradoi, and the mussel, Mytilus edulis chilensis, in the Falkland Islands (South-west Atlantic) is reported. Isopods were recorded within the mantle cavity of mussels from an estuarine location, Camilla Creek, and from two coastal sites, Goose Green and Darwin. All the mussel populations sampled along the estuary harboured isopods, whereas only those from the low and low-mid shore sites at Darwin and Goose Green were infested. Overall infestation increased between October 1994 and December 1995 from 47, 9 and 2 to 51, 21 and 24% at Camilla Creek, Goose Green and Darwin, respectively. Infestation also increased with decreasing tidal elevation but declined with mussel size. There was no apparent correlation between the occurrence of the isopod and salinity along the estuary at Camilla Creek. Isopod abundance increased with mussel size at all sites and tidal levels, and the largest broods were generally present in mussels from the low shore. Length-frequency distributions of the isopod populations were distinctly bimodal and comprised a prominent mode of males and juvenile individuals, up to 9 mm in size, and a smaller mode containing the adult females, ranging from 5 to 14 mm. Never more than one female was found within any given mussel, and this was always the largest isopod present. No significant differences in condition were observed between mussels that were infested and those that were not.

  2. Impact of a microphallid trematode on the behaviour and survival of its isopod intermediate host: phylogenetic inheritance?

    PubMed

    Hansen, Ellen K; Poulin, Robert

    2005-10-01

    The extent to which the ability of parasites to alter host behaviour is phylogenetically inherited as opposed to independently evolved has received little attention. We investigated the impact of an undescribed species of Microphallus on the behaviour and survival of its host, the freshwater isopod Austridotea annectens, to determine if it produced effects comparable to those induced by other trematodes of this genus. There was no difference between the vertical distribution and responses to light of infected isopods and those of uninfected isopods. In contrast, we found that infected isopods were more active swimmers than uninfected isopods, and that they failed to show the evasive responses shown by uninfected isopods when exposed to a simulated predator. There was no detectable effect of Microphallus infection on isopod survival, however. Overall, our results provide no strong evidence that the behavioural manipulation shown by our Microphallus species and that displayed by the well-studied Microphallus papillorobustus are inherited from a common ancestor rather than independently derived. PMID:15997403

  3. Human Health at the Beach

    MedlinePLUS

    ... near the site where polluted discharges enter the water. Pollution can also come from high concentrations of farm ... is available online. Other Beach Safety Topics Beyond water pollution, there are other potential threats to human health ...

  4. Evidence for Permo-Triassic colonization of the deep sea by isopods.

    PubMed

    Lins, Luana S F; Ho, Simon Y W; Wilson, George D F; Lo, Nathan

    2012-12-23

    The deep sea is one of the largest ecosystems on Earth and is home to a highly diverse fauna, with polychaetes, molluscs and peracarid crustaceans as dominant groups. A number of studies have proposed that this fauna did not survive the anoxic events that occurred during the Mesozoic Era. Accordingly, the modern fauna is thought to be relatively young, perhaps having colonized the deep sea after the Eocene/Oligocene boundary. To test this hypothesis, we performed phylogenetic analyses of nuclear ribosomal 18S and 28S and mitochondrial cytochrome oxidase I and 16S sequences from isopod crustaceans. Using a molecular clock calibrated with multiple isopod fossils, we estimated the timing of deep-sea colonization events by isopods. Our results show that some groups have an ancient origin in the deep sea, with the earliest estimated dates spanning 232-314 Myr ago. Therefore, anoxic events at the Permian-Triassic boundary and during the Mesozoic did not cause the extinction of all the deep-sea fauna; some species may have gone extinct while others survived and proliferated. The monophyly of the 'munnopsid radiation' within the isopods suggests that the ancestors of this group evolved in the deep sea and did not move to shallow-water refugia during anoxic events. PMID:23054914

  5. TEST OF CRITERIA FOR INTRODUCED SPECIES: THE GLOBAL INVASION BY THE ISOPOD SYNIDOTEA LAEVIDORDALIS (MEIRS 1881)

    EPA Science Inventory

    Criteria for distinguishing introduced from endemic peracaridan crustaceans were used to deduce that a human-borne global invasion by the Oriental isopod Synidotea laevidorsalis (Meirs 1881) has occurred in the past 100 years. hese criteria concern the ecological, evolutionary, a...

  6. Isopods Failed to Acclimate Their Thermal Sensitivity of Locomotor Performance during Predictable or Stochastic Cooling

    PubMed Central

    Schuler, Matthew S.; Cooper, Brandon S.; Storm, Jonathan J.; Sears, Michael W.; Angilletta, Michael J.

    2011-01-01

    Most organisms experience environments that vary continuously over time, yet researchers generally study phenotypic responses to abrupt and sustained changes in environmental conditions. Gradual environmental changes, whether predictable or stochastic, might affect organisms differently than do abrupt changes. To explore this possibility, we exposed terrestrial isopods (Porcellio scaber) collected from a highly seasonal environment to four thermal treatments: (1) a constant 20°C; (2) a constant 10°C; (3) a steady decline from 20° to 10°C; and (4) a stochastic decline from 20° to 10°C that mimicked natural conditions during autumn. After 45 days, we measured thermal sensitivities of running speed and thermal tolerances (critical thermal maximum and chill-coma recovery time). Contrary to our expectation, thermal treatments did not affect the thermal sensitivity of locomotion; isopods from all treatments ran fastest at 33° to 34°C and achieved more than 80% of their maximal speed over a range of 10° to 11°C. Isopods exposed to a stochastic decline in temperature tolerated cold the best, and isopods exposed to a constant temperature of 20°C tolerated cold the worst. No significant variation in heat tolerance was observed among groups. Therefore, thermal sensitivity and heat tolerance failed to acclimate to any type of thermal change, whereas cold tolerance acclimated more during stochastic change than it did during abrupt change. PMID:21698113

  7. Are foraminifers (Protozoa) important food for small isopods (Crustacea) in the deep sea?

    NASA Astrophysics Data System (ADS)

    Gudmundsson, Gudmundur; von Schmalensee, Menja; Svavarsson, Jörundur

    2000-11-01

    Gut contents of three small (<6 mm) species of munnopsid asellote isopod crustaceans ( Echinozone arctica, Ilyarachna bergendali and I. torleivi) from bathyal depths in the Nordic Seas were examined. The species feed mainly on benthic foraminifers, and their gut contents reflect the functional capability of the mouthparts in partitioning the food. Fragments of small and fragile calcareous foraminifer protozoans and small hard agglutinating foraminifers were most important in the guts of Echinozone arctica, which has rounded mandibular molar process, suited for crunching the foraminifers. Dark- and light-gray stercomata (foraminifer fecal pellets) from soft agglutinating foraminifers were most important in the guts of Ilyarachna bergendali, whose molar process has a wide crunching cusp and a sharp cutting edge. The gut contents of Ilyarachna torleivi were similar to the contents of I. bergendali, but differed somewhat from those of E. arctica. The results indicate that foraminiferivory may be common among small munnopsid asellote isopods and that the isopods may specialize in certain foraminifer species or genera. The strength of the foraminifer test may be an important aid against predation. This study indicates that small, yet poorly known, soft-shelled and agglutinating foraminifers with a low nutritional value may be important as food for deep-water isopods and that foraminifers may be an important link between phytodetritus and the macrofauna.

  8. Assemblages of terrestrial isopods (Isopoda, Oniscidea) in a fragmented forest landscape in Central Europe

    PubMed Central

    Tajovský, Karel; Hošek, Jan; Hofmeister, Jeňýk; Wytwer, Jolanta

    2012-01-01

    Abstract Terrestrial isopods were collected in 13 forest fragments differing in area (within the range of 0.1 and 254.5 ha), shape and composition of forest vegetation (thermophilous oak, mesophilous oak-hornbeam, thermophilous oak-hornbeam, acidophilous oak, basiphilous oak, beech oak-hornbeam, moist mixed deciduous forest, plantations of deciduous and coniferous trees), all situated in the Český kras Protected Landscape Area, Czech Republic, Central Europe. Number of sites sampled in each fragment of forest depended on its size and ranged from 1 to 7. Altogether 30 sites were sampled. Soil samples (5 per site collected twice a year) and pitfall trapping (5 traps per site in continuous operation throughout a year) during 2008–2009 yielded a total of 14 species of terrestrial isopods. The highest densities and highest epigeic activities of terrestrial isopods were recorded in the smallest fragments of woodland. Although a wider range of habitats were sampled in the larger fragments of woodland there was not a greater diversity of species there and the population densities and epigeic activities recorded there were lower. Porcellium collicola was most abundant in small fragments of woodland regardless the vegetation there. Armadillidium vulgare and Protracheoniscus politus were statistically more abundant in the larger fragments of woodland. The results indicate that forest fragmentation does not necessarily result in a decrease in the species richness of the isopod assemblages in such habitats. PMID:22536108

  9. Assemblages of terrestrial isopods (Isopoda, Oniscidea) in a fragmented forest landscape in Central Europe.

    PubMed

    Tajovský, Karel; Hošek, Jan; Hofmeister, Jeňýk; Wytwer, Jolanta

    2012-01-01

    Terrestrial isopods were collected in 13 forest fragments differing in area (within the range of 0.1 and 254.5 ha), shape and composition of forest vegetation (thermophilous oak, mesophilous oak-hornbeam, thermophilous oak-hornbeam, acidophilous oak, basiphilous oak, beech oak-hornbeam, moist mixed deciduous forest, plantations of deciduous and coniferous trees), all situated in the Český kras Protected Landscape Area, Czech Republic, Central Europe. Number of sites sampled in each fragment of forest depended on its size and ranged from 1 to 7. Altogether 30 sites were sampled. Soil samples (5 per site collected twice a year) and pitfall trapping (5 traps per site in continuous operation throughout a year) during 2008-2009 yielded a total of 14 species of terrestrial isopods. The highest densities and highest epigeic activities of terrestrial isopods were recorded in the smallest fragments of woodland. Although a wider range of habitats were sampled in the larger fragments of woodland there was not a greater diversity of species there and the population densities and epigeic activities recorded there were lower. Porcellium collicola was most abundant in small fragments of woodland regardless the vegetation there. Armadillidium vulgare and Protracheoniscus politus were statistically more abundant in the larger fragments of woodland. The results indicate that forest fragmentation does not necessarily result in a decrease in the species richness of the isopod assemblages in such habitats. PMID:22536108

  10. POPULATION STRUCTURE AND ENERGETICS OF THE BOPRYID ISOPOD PARASITE ORTHIONE GRIFFENIS IN MUD SHRIMP UPOGEBIA PUGETTENSIS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The population structure and energetic burden of bopyrid isopod parasite Orthione griffenis on the eastern Pacific mud shrimp Upogebia pugettensis are estimated from size and weight relationships between parasite and host. U. pugettensis weight loss increases with O. griffenis weight but the high v...

  11. Toxicity of abamectin to the terrestrial isopod Porcellio scaber (Isopoda, Crustacea).

    PubMed

    Kolar, Lucija; Jemec, Anita; van Gestel, Cornelis A M; Valant, Janez; Hrzenjak, Rok; Erzen, Nevenka Kozuh; Zidar, Primoz

    2010-06-01

    To determine effects of the antiparasitic veterinary drug abamectin on the isopod Porcellio scaber, animals were exposed for 21 days to Lufa 2.2 soil spiked at concentrations of 3-300 mg/kg dry soil. After exposure, abamectin residues in the isopods were analysed using a novel analytical method. Toxicity was evaluated on different levels of biological organisation: biochemical, cellular and the individual organism. Measurements included glutathione S-transferase (GST) activity and stability of cell membranes in the digestive gland, animal mass gain or loss, food consumption, behaviour and mortality. LC50 for the effect of abamectin on survival of P. scaber was 71 mg/kg dry soil. The most obvious sublethal effects were reduced food consumption and decreased body mass (NOEC 3 mg/kg dry soil). Additionally, loss of digging activity and reduced GST activity (NOEC 30 mg/kg dry soil) and cell membrane destabilization (NOEC 10 mg/kg dry soil) were recorded. Abamectin only slightly accumulated in the isopods, with bioaccumulation factors always being <0.1. Based on these results and current information on environmental levels of abamectin, it is not likely that isopods will be affected by abamectin, but further studies with exposure through faeces are recommended. PMID:20217223

  12. Habitat-specific pigmentation in a freshwater isopod: adaptive evolution over a small spatiotemporal scale.

    PubMed

    Hargeby, Anders; Johansson, Jonas; Ahnesjö, Jonas

    2004-01-01

    Pigmentation in the freshwater isopod Asellus aquaticus (Crustacea) differed between habitats in two Swedish lakes. In both lakes, isopods had lighter pigmentation in stands of submerged vegetation, consisting of stoneworts (Chara spp.), than in nearby stands of reed (Phragmites australis). Experimental crossings of light and dark isopods in a common environment showed that pigmentation had a genetic basis and that genetic variance was additive. Environmental effects of diet or chromatophore adjustment to the background had minor influence on pigmentation, as shown by laboratory rearing of isopods on stonewort or reed substrates, as well as analyses of stable isotope ratios for isopods collected in the field. In both study lakes, the average phenotype became lighter with time (across generations) in recently established stonewort stands. Taken together, these results indicate that altered phenotype pigmentation result from evolutionary responses to local differences in natural selection. Based on the assumption of two generations per year, the evolutionary rate of change in pigmentation was 0.08 standard deviations per generation (haldanes) over 20 generations in one lake and 0.22 haldanes over two generations in the other lake. This genetic change occurred during an episode of population growth in a novel habitat, a situation known to promote adaptive evolution. In addition, stonewort stands constitute large and persistent patches, characteristics that tend to preserve local adaptations produced by natural selection. Results from studies on selective forces behind the adaptive divergence suggest that selective predation from visually oriented predators is a possible selective agent. We found no indications of phenotype-specific movements between habitats. Mating within stonewort stands was random with respect to pigmentation, but on a whole-lake scale it is likely that mating is assortative, as a result of local differences in phenotype distribution. PMID:15058721

  13. Occurrence and assemblage composition of millipedes (Myriapoda, Diplopoda) and terrestrial isopods (Crustacea, Isopoda, Oniscidea) in urban areas of Switzerland

    PubMed Central

    Vilisics, Ferenc; Bogyó, Dávid; Sattler, Thomas; Moretti, Marco

    2012-01-01

    Abstract Terrestrial isopods and millipedes, members of the invertebrate macro-decomposer guild, were collected through pitfall traps in three Swiss cities (Zurich, Lucerne, Lugano). A total of 7,198 individuals of 17 isopod species (7093 ind.), and 10 millipede species (105 ind.) were captured. Besides the Alpine endemic isopod (Trichoniscus alemannicus) and millipede (Cylindroiulus verhoeffi), urban assemblages were mainly composed of widespread, native European and even cosmopolitan species, which are frequent in anthropogenic areas. Overall species richness (isopods and millipedes combined) was similar in Zurich (17 species) and Lucerne (16), while only 13 species were sampled in Lugano. According to the Sørensen index of similarity, species composition of Zurich and Lucerne were more alike, while the one of Lugano was more distinct from the other two cities. This result can be explained by the spatial proximity of Zurich and Lucerne in the north of the Alps compared to Lugano, which is located more distantly and in the south of the Alps. Dominant isopods and millipedes in Zurich and Lucerne were found to be widespread synanthropic species in temperate Europe(Porcellio scaber, Trachelipus rathkii and Ophyiulus pilosus) while the dominant isopod in Lugano (Trachelipus razzautii) is a species with a north-eastern Mediterranean distribution. Our study reveals that the urban millipede and isopod fauna in Swiss cities mainly consists of widespread species, but species of narrower distribution (e.g. Trichoniscus alemannicus, Cylindroiulus verhoeffi) may also find suitable habitats in cities. Despite some signs of biotic homogenization, our study also found compositional differences of millipede and isopod assemblages between northern and southern cities that suggest geographical effects of the regional species pool. PMID:22536109

  14. The role of macrophytes as a refuge and food source for the estuarine isopod Exosphaeroma hylocoetes (Barnard, 1940)

    NASA Astrophysics Data System (ADS)

    Henninger, Tony O.; Froneman, P. William; Richoux, Nicole B.; Hodgson, Alan N.

    2009-04-01

    The role of submerged macrophytes as refugia from fish predation and as possible food sources for the estuarine isopod Exosphaeroma hylocoetes ( Barnard, K.H., 1940) was investigated. Laboratory experiments tested the effectiveness of artificial vegetation, replicating submerged vegetation, in enabling isopods to elude selected fish predators Rhabdosargus holubi, Glossogobius callidus, Monodactylus falciformis and Clinus cottoides. Isopods preferentially hid in the vegetation (>90%), even in absence of fish. The predatory fish had varying success in finding isopods within the vegetation. Isopod mortality ranged from 2% ( R. holubi) to a maximum of 87% ( C. cottoides) within vegetation, depending on the fish predator present. Stable isotope and fatty acid analyses ruled out the submerged macrophyte Ruppia maritima and inundated fringing grasses as direct food sources, but highlighted the epiphytic biota (mainly diatoms) found on the submerged vegetation and sediments as more likely food sources. These findings are consistent with gut content analyses. The results suggest that the close association of E. hylocoetes with R. maritima is the result of the vegetation providing the isopod with a refuge against fish predation as well as areas of increased food availability.

  15. Brain anatomy of the marine isopod Saduria entomon Linnaeus, 1758 (Valvifera, Isopoda) with special emphasis on the olfactory pathway

    PubMed Central

    Kenning, Matthes; Harzsch, Steffen

    2013-01-01

    Representatives of at least six crustacean taxa managed to establish a terrestrial life style during their evolutionary history and the Oniscidea (Isopoda) are currently held as the most successfully terrestrialized malacostracan crustaceans. The brain architecture of terrestrial isopods is fairly well understood and studies on this field suggest that the evolutionary transition from sea to land in isopods coincided with a considerable size reduction and functional loss of their first pair of antennae and associated brain areas. This finding suggests that terrestrial isopods may have no or poor abilities to detect volatile substances but that their chemosensory ecology is most likely restricted to contact chemoreception. In this study, we explored how the brain of a marine isopod and particularly its olfactory system compares to that of terrestrial relatives. Using histochemical and immunohistochemical labeling, brightfield and confocal laser-scan microscopy, we show that in the marine isopod Saduria entomon aesthetascs on the first pair of antennae provide input to a well defined deutocerebrum (DC). The deutocerebral chemosensory lobes (DCL) are divided into spherical neuropil compartments, the olfactory glomeruli (og). Secondary processing areas in the lateral protocerebrum (lPC) are supplied by a thin but distinct projection neuron tract (PNT) with a contralateral connection. Hence, contrary to terrestrial Isopoda, S. entomon has at least the neuronal substrate to perceive and process olfactory stimuli suggesting the originally marine isopod lineage had olfactory abilities comparable to that of other malacostracan crustaceans. PMID:24109435

  16. 33 CFR 100.736 - Annual Fort Myers Beach air show; Fort Myers Beach, FL.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Annual Fort Myers Beach air show; Fort Myers Beach, FL. 100.736 Section 100.736 Navigation and Navigable Waters COAST GUARD, DEPARTMENT... Fort Myers Beach air show; Fort Myers Beach, FL. (a)(1) Regulated Area. The regulated area is formed...

  17. 33 CFR 100.736 - Annual Fort Myers Beach air show; Fort Myers Beach, FL.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Annual Fort Myers Beach air show; Fort Myers Beach, FL. 100.736 Section 100.736 Navigation and Navigable Waters COAST GUARD, DEPARTMENT... Fort Myers Beach air show; Fort Myers Beach, FL. (a)(1) Regulated Area. The regulated area is formed...

  18. Differentiating Experts' Anticipatory Skills in Beach Volleyball

    ERIC Educational Resources Information Center

    Canal-Bruland, Rouwen; Mooren, Merel; Savelsbergh, Geert J. P.

    2011-01-01

    In this study, we examined how perceptual-motor expertise and watching experience contribute to anticipating the outcome of opponents' attacking actions in beach volleyball. To this end, we invited 8 expert beach volleyball players, 8 expert coaches, 8 expert referees, and 8 control participants with no beach volleyball experience to watch videos…

  19. A Study of Sandy Beach Zonation.

    ERIC Educational Resources Information Center

    Alexander, Steve K.

    1991-01-01

    Describes the study of sandy beach zonations as a seashore activity for either high school or lower-level college courses in biology, ecology, or marine biology. Students first draw a profile of a beach scene and then collect specimens from the zones of the shore. In a laboratory, students identify their specimens and relate them to the beach…

  20. Differentiating Experts' Anticipatory Skills in Beach Volleyball

    ERIC Educational Resources Information Center

    Canal-Bruland, Rouwen; Mooren, Merel; Savelsbergh, Geert J. P.

    2011-01-01

    In this study, we examined how perceptual-motor expertise and watching experience contribute to anticipating the outcome of opponents' attacking actions in beach volleyball. To this end, we invited 8 expert beach volleyball players, 8 expert coaches, 8 expert referees, and 8 control participants with no beach volleyball experience to watch videos…

  1. Changes in behavioural trait integration following rapid ecotype divergence in an aquatic isopod.

    PubMed

    Harris, S; Eroukhmanoff, F; Green, K K; Svensson, E I; Pettersson, L B

    2011-09-01

    Colonization of new habitats can relax selection pressures, and traits or trait combinations no longer selected for might become reduced or lost. We investigated behavioural differentiation and behavioural trait integration in the freshwater isopod Asellus aquaticus. This isopod has recently colonized a novel habitat and diverged into two ecotypes which encounter different predator faunas. We investigated sex-specific behavioural differences and phenotypic integration in three behavioural assays: (i) time to emerge (TE) from a shelter, (ii) activity and (iii) escape behaviour. General activity and escape behaviour differed between ecotypes. Furthermore, general activity and TE differed between sexes. Behavioural traits were more frequently correlated in the ancestral habitat, and phenotypic integration tended to be higher in this habitat as well. Our study suggests that different predator types, but also other ecological factors such as habitat matrices and population densities, might explain the differences in behavioural integration in these ecotypes. PMID:21658187

  2. Burrow plasticity in the deep-sea isopod Bathynomus doederleini (Crustacea: Isopoda: Cirolanidae).

    PubMed

    Matsui, Toshinori; Moriyama, Tohru; Kato, Ryuichi

    2011-12-01

    We investigated whether the deep-sea isopod Bathynomus doederleini has the capacity to change burrow length in response to changes in environmental conditions. We observed burrowing behavior in individuals that were placed on substrates with either simple (ST) or complex (CT) surface topographies. Individuals in the ST group (N = 10) constructed seven burrows. The mean ratio of the burrow length to body length was 1.8. The individuals in the CT group (N = 10) constructed eight burrows with a mean ratio of burrow length to body length of 2.5. Thus the burrows were significantly longer in the CT group. In addition, the isopods in the CT group often incorporated a chamber in the mid-section of the burrow. Our results may be used to infer the determinants of burrow morphology and speculate about the lifestyle of this species in the deep sea. PMID:22132782

  3. Acute toxicity of cadmium to eight species of marine amphipod and isopod crustaceans from southern California

    SciTech Connect

    Hong, J.S.; Reish, D.J.

    1987-11-01

    Amphipods and isopods are important components of the marine intertidal and subtidal fauna where they are found on or in the substrate or among spaces between larger, attached organisms. However, in spite of their abundance and importance, the use of these two endemic marine groups has been limited in comparison to decapods in marine toxicological research. The purpose of this study was to investigate the effect of a single metallic salt, CdCl/sub 2/, on six species of amphipods and two species of isopods under similar experimental conditions. Cadmium was selected as the toxicant in this comparative study since this metal is an important constituent in municipal wastes discharged into southern California marine waters.

  4. Beach lamination: Nature and origin

    USGS Publications Warehouse

    Clifton, H.E.

    1969-01-01

    A distinctive two-fold sedimentation unit characterizes lamination in the upper swash zone of beaches. Within the unit a fine and/or a heavy mineral rich layer at the base grades upward into a coarser and/or a heavy mineral poor layer at the top. This distinctive type of lamination results from grain segregation within bed flow during wave backwash. ?? 1969.

  5. The shapes of beach pebbles

    USGS Publications Warehouse

    Wentworth, Chester K.

    1923-01-01

    There is much confusion in geologic literature as to the shapes of fluvial and beach pebbles and the differences between them, if differences exist. Though the contrary has been asserted, most geologists who have written on the subject appear to hold the view that beach pebbles are generally flatter than river pebbles, having discoid, lozenge-shaped, ellipsoid, or oval forms. It is asserted by some that these forms are produced by pushing of the rock fragments to and fro by the waves. Others have considered that the shapes of the original fragments and the inherent structure of the rock are dominant in determining the shapes of beach pebbles, and with this view the writer is in accord. That beach pebbles, even those composed of massive igneous rocks are commonly of a flattened oval form seems certain, as has been stated elsewhere, but this fact is probably to be attributed to the development of such forms from original flat fragments or from rocks of schistose structure or to the segregation of such forms under the peculiar action of the waves, rather than to their production by a specialized wave abrasion.

  6. Inside the "Long Beach Way"

    ERIC Educational Resources Information Center

    Olson, Lynn

    2007-01-01

    This article features Long Beach Unified School District, the 2003 winner of a prestigious prize in urban education. The district of more than 90,000 students is the first winner of the award to return to the competition as a finalist. Its reappearance on the list after earning the prize in 2003 raises interesting questions about how districts…

  7. Inside the "Long Beach Way"

    ERIC Educational Resources Information Center

    Olson, Lynn

    2007-01-01

    This article features Long Beach Unified School District, the 2003 winner of a prestigious prize in urban education. The district of more than 90,000 students is the first winner of the award to return to the competition as a finalist. Its reappearance on the list after earning the prize in 2003 raises interesting questions about how districts…

  8. Adaptive variation in offspring size in the terrestrial isopod, Armadillidium vulgare

    USGS Publications Warehouse

    Brody, M.S.; Lawlor, L.R.

    1984-01-01

    Variation in the birth size of offspring of the terrestrial isopod, Armadillidium vulgare, was observed in laboratory experiments and in field populations. In the laboratory, larger offspring were produced when the mother's food supply was reduced. In field populations, larger offspring were produced during the summer, a period of reduced food availability. Smaller offspring are produced in the spring, when food is readily available. Females may be making larger young to increase survival during the more severe conditions of the summer breeding period.

  9. Virtual Beach 3: user's guide

    USGS Publications Warehouse

    Cyterski, Mike; Brooks, Wesley; Galvin, Mike; Wolfe, Kurt; Carvin, Rebecca; Roddick, Tonia; Fienen, Mike; Corsi, Steve

    2014-01-01

    Virtual Beach version 3 (VB3) is a decision support tool that constructs site-specific statistical models to predict fecal indicator bacteria (FIB) concentrations at recreational beaches. VB3 is primarily designed for beach managers responsible for making decisions regarding beach closures or the issuance of swimming advisories due to pathogen contamination. However, researchers, scientists, engineers, and students interested in studying relationships between water quality indicators and ambient environmental conditions will find VB3 useful. VB3 reads input data from a text file or Excel document, assists the user in preparing the data for analysis, enables automated model selection using a wide array of possible model evaluation criteria, and provides predictions using a chosen model parameterized with new data. With an integrated mapping component to determine the geographic orientation of the beach, the software can automatically decompose wind/current/wave speed and magnitude information into along-shore and onshore/offshore components for use in subsequent analyses. Data can be examined using simple scatter plots to evaluate relationships between the response and independent variables (IVs). VB3 can produce interaction terms between the primary IVs, and it can also test an array of transformations to maximize the linearity of the relationship The software includes search routines for finding the "best" models from an array of possible choices. Automated censoring of statistical models with highly correlated IVs occurs during the selection process. Models can be constructed either using previously collected data or forecasted environmental information. VB3 has residual diagnostics for regression models, including automated outlier identification and removal using DFFITs or Cook's Distances.

  10. Terrestrial isopod community as indicator of succession in a peat bog.

    PubMed

    Antonović, Ivan; Brigić, Andreja; Sedlar, Zorana; Bedek, Jana; Soštarić, Renata

    2012-01-01

    Terrestrial isopods were studied in the Dubravica peat bog and surrounding forest in the northwestern Croatia. Sampling was conducted using pitfall traps over a two year period. Studied peat bog has a history of drastically decrease in area during the last five decades mainly due to the process of natural succession and changes in the water level. A total of 389 isopod individuals belonging to 8 species were captured. Species richness did not significantly differ between bog, edge and surrounding forest. High species richness at the bog is most likely the result of progressive vegetation succession, small size of the bog and interspecific relationships, such as predation. With spreading of Molinia grass on the peat bog, upper layers of Sphagnum mosses become less humid and probably more suitable for forest species that slowly colonise bog area. The highest diversity was found at the edge mainly due to the edge effect and seasonal immigration, but also possibly due to high abundance and predator pressure of the Myrmica ants and lycosid spiders at the bog site. The most abundant species were Trachelipus rathkii and Protracheoniscus politus, in the bog area and in the forest, respectively. Bog specific species were not recorded and the majority of the species collected belong to the group of tyrphoneutral species. However, Hyloniscus adonis could be considered as a tyrphoxenous species regarding its habitat preferences. Most of collected isopod species are widespread eurytopic species that usually inhabit various habitats and therefore indicate negative successive changes or degradation processes in the peat bog. PMID:22536107

  11. Study of the functional morphology of mouthparts of parasitic isopods of marine fishes

    PubMed Central

    Rameshkumar, Ganapathy; Ravichandran, Samuthirapandian; Allayie, Sartaj Ahmad

    2013-01-01

    Objective To carry out a comparative study of the mouthparts and the diet of eight isopod fish parasites. Methods A description of the mouthparts, together with their diet nature, was derived both by direct observation and an interpretation of their structure. The three-dimensional study of the mouthparts of the isopod parasites was done to reveal their morphology. Results Observations revealed that these species are wholly carnivorous. Result shows how they are adapted for tearing and bolting fish food material. The mouthparts consist of a labrum, paragnaths, paired mandibles, maxillules, maxillae and maxillipeds. The labrum and the paragnaths are the least developed but peculiarly the mandibles are asymmetrical, large, stout and highly modified. The analysis of gut contents indicated that Cymothoa indica and Joryma brachysoma diet consisted of 90% to 95% of animal blood. The diet of Mothocya renardi, Ryukyua circularis and Joryma hilsae were mainly composed of mucus (80%-90%). The stomach contents of Nerocila phaeopleura and Nerocila sundaica, were dominated by body muscles (75%-83%). Conclusions The possible functions of the mouthparts, especially in feeding are discussed in light of their structure. The morphology of the mouthparts of the isopod parasites are heavily modified with their feeding behavior.

  12. Toxicity interaction between chlorpyrifos, mancozeb and soil moisture to the terrestrial isopod Porcellionides pruinosus.

    PubMed

    Morgado, Rui G; Gomes, Pedro A D; Ferreira, Nuno G C; Cardoso, Diogo N; Santos, Miguel J G; Soares, Amadeu M V M; Loureiro, Susana

    2016-02-01

    A main source of uncertainty currently associated with environmental risk assessment of chemicals is the poor understanding of the influence of environmental factors on the toxicity of xenobiotics. Aiming to reduce this uncertainty, here we evaluate the joint-effects of two pesticides (chlorpyrifos and mancozeb) on the terrestrial isopod Porcellionides pruinosus under different soil moisture regimes. A full factorial design, including three treatments of each pesticide and an untreated control, were performed under different soil moisture regimes: 25%, 50%, and 75% WHC. Our results showed that soil moisture had no effects on isopods survival, at the levels assessed in this experiment, neither regarding single pesticides nor mixture treatments. Additivity was always the most parsimonious result when both pesticides were present. Oppositely, both feeding activity and biomass change showed a higher sensitivity to soil moisture, with isopods generally showing worse performance when exposed to pesticides and dry or moist conditions. Most of the significant differences between soil moisture regimes were found in single pesticide treatments, yet different responses to mixtures could still be distinguished depending on the soil moisture assessed. This study shows that while soil moisture has the potential to influence the effects of the pesticide mixture itself, such effects might become less important in a context of complex combinations of stressors, as the major contribution comes from its individual interaction with each pesticide. Finally, the implications of our results are discussed in light of the current state of environmental risk assessment procedures and some future perspectives are advanced. PMID:26539709

  13. Temperature, physiological time, and zinc toxicity in the isopod, Porcellio scaber

    SciTech Connect

    Donker, M.H.; Van Straalen, N.M.; Abdel-Lateif, H.M.; Khalil, M.A.; Bayoumi, B.M.

    1998-08-01

    Temperature is an important controlling factor in the metabolism of ectotherms, and it may interact with the toxicity of heavy metals in a variety of ways. In this work, a study on the effect of different zinc concentrations on growth of the isopod, Porcellio scaber was conducted using four temperature levels. The results demonstrated a significant effect for both zinc and temperature on the growth rate; the interaction between zinc and temperature was also significant. The Arrhenius function was used to describe the temperature-growth rate relationship, from which estimates for the activation energy were derived. A tendency for activation energy to decrease with increasing zinc concentration was observed. Isopods exposed to 13 {micro}mol Zn/g had the highest activation energy and the highest growth rate. To analyze the effect of temperature on the internal body concentration of zinc, the exposure time was transformed into physiological time, calibrated at 15 C, for all experimental groups using the activation energies estimated earlier. The rate of zinc accumulation was derived from the relationship between internal body concentration and physiological exposure time. Differences between isopods cultured at different temperatures could be explained well by the effect of physiological exposure time. The interaction between temperature and zinc toxicity seems to be due not to increased accumulation of zinc at higher temperatures as such but to a physiological interaction with the energy metabolism.

  14. Recharge into a shingle beach

    NASA Astrophysics Data System (ADS)

    Keating, T.

    1984-04-01

    Traditionally, groundwater recharge in the U.K. has been calculated by the Penman method on a monthly basis, using values of potential evaporation derived from averaged meteorological data and monthly totals of rainfall. Recent work by K.W.F. Howard and J.W. Lloyd has shown that these monthly totals considerably underestimate recharge calculated over shorter time periods and they suggested that 1-day, or at worst, 10-day intervals should be used. In this paper field experiments to measure recharge into a shingle beach are reported. These experiments were made with a lysimeter over a 6-yr. period and have shown that recharge into the shingle occurs whenever significant precipitation occurs, even during the summer months. The Penman model is shown to be unrealistic for estimating recharge into such a beach and an alternative model for calculating recharge is proposed. This model is shown to yield good results.

  15. Contact with beach sand among beach-goers and risk of illness

    EPA Science Inventory

    Background: Recently, numerous studies of fecal contamination of beach sand have triggered interest among scientists, the news media, and the general public. Evidence shows that beach sand harbors higher concentrations of fecal indicator organisms (microbes considered to indicate...

  16. Beach monitoring criteria: reading the fine print

    USGS Publications Warehouse

    Nevers, Meredith B.; Whitman, Richard L.

    2011-01-01

    Beach monitoring programs aim to decrease swimming-related illnesses resulting from exposure to harmful microbes in recreational waters, while providing maximum beach access. Managers are advised by the U.S. EPA to estimate microbiological water quality based on a 5-day geometric mean of fecal indicator bacteria (FIB) concentrations or on a jurisdiction-specific single-sample maximum; however, most opt instead to apply a default single-sample maximum to ease application. We examined whether re-evaluation of the U.S. EPA ambient water quality criteria (AWQC) and the epidemiological studies on which they are based could increase public beach access without affecting presumed health risk. Single-sample maxima were calculated using historic monitoring data for 50 beaches along coastal Lake Michigan on various temporal and spatial groupings to assess flexibility in the application of the AWQC. No calculation on either scale was as low as the default maximum (235 CFU/100 mL) that managers typically use, indicating that current applications may be more conservative than the outlined AWQC. It was notable that beaches subject to point source FIB contamination had lower variation, highlighting the bias in the standards for these beaches. Until new water quality standards are promulgated, more site-specific application of the AWQC may benefit beach managers by allowing swimmers greater access to beaches. This issue will be an important consideration in addressing the forthcoming beach monitoring standards.

  17. NOWCASTING AND FORECASTING BEACH BACTERIA CONCENTRATIONS USING EPA VIRTUAL BEACH SOFTWARE

    EPA Science Inventory

    Evidence shows that traditional persistence-based beach closure decision making is inadequate, beaches are closed when they could be open and kept open when they should be closed. Intense interest is now focused on efforts to nowcast beach conditions using surrogate variables, su...

  18. 76 FR 54703 - Safety Zone; Myrtle Beach Triathlon, Atlantic Intracoastal Waterway, Myrtle Beach, SC

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-02

    ... Triathlon, Atlantic Intracoastal Waterway, Myrtle Beach, SC in the Federal Register (76 FR 124). We received... Intracoastal Waterway, Myrtle Beach, SC AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The... Intracoastal Waterway, Myrtle Beach, SC. (a) Regulated Area. The following regulated area is a safety zone....

  19. 76 FR 37700 - Safety Zone; Myrtle Beach Triathlon, Atlantic Intracoastal Waterway, Myrtle Beach, SC

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-28

    ... notice regarding our public dockets in the January 17, 2008, issue of the Federal Register (73 FR 3316... Intracoastal Waterway, Myrtle Beach, SC AGENCY: Coast Guard, DHS. ACTION: Notice of proposed rulemaking... Beach Triathlon, Atlantic Intracoastal Waterway, Myrtle Beach, SC. (a) Regulated Area. The...

  20. VISUAL BEACH: SOFTWARE FOR ACHIEVING BEACH AESTHETIC AND PUBLIC HEALTH PROTECTION

    EPA Science Inventory

    The Beaches Environmental Assessment and Coastal Health Act of 2000 directs the EPA to assure that 100% of significant public beaches are managed by 2008. Under the Act EPA is developing a program to monitor beach water quality and strategies for timely notification of the public...

  1. USING HYDROGRAPHIC DATA AND THE EPA VIRTUAL BEACH MODEL TO TEST PREDICTIONS OF BEACH BACTERIA CONCENTRATIONS

    EPA Science Inventory

    A modeling study of 2006 Huntington Beach (Lake Erie) beach bacteria concentrations indicates multi-variable linear regression (MLR) can effectively estimate bacteria concentrations compared to the persistence model. Our use of the Virtual Beach (VB) model affirms that fact. VB i...

  2. 122. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: LAYOUT OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    122. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: LAYOUT OF EXTENSION TO PIER Sheet 4 of 11 (#3276) - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  3. 125. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: MODIFIED RAMP ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    125. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: MODIFIED RAMP DETAILS Sheet 6A of 11 (#3279) - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  4. 10. GROUND VIEW OF PIER, LOOKING SOUTH FROM BEACH; SHOWING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. GROUND VIEW OF PIER, LOOKING SOUTH FROM BEACH; SHOWING (LEFT-RIGHT) CAPTAIN'S GALLEY'S GALLEY TO END OF PIER - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  5. 7. GROUND VIEW OF PIER, LOOKING EAST FROM BEACH; SHOWING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. GROUND VIEW OF PIER, LOOKING EAST FROM BEACH; SHOWING 27TH BENT LANDWARD TO MAXWELL'S RESTAURANT, NEPTUNE'S GALLEY (RIGHT OF CENTER) - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  6. 121. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: LAYOUT OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    121. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: LAYOUT OF EXISTING PIER Sheet 3 of 11 (#3275) - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  7. 127. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: FRAMING DETAILS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    127. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: FRAMING DETAILS Sheet 8 of 11 (#3281) - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  8. 128. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: BOAT LANDING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    128. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: BOAT LANDING DETAILS Sheet 9 of 11 (#3282) - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  9. 111. PLAN AND ELEVATION OF HUNTINGTON BEACH MUNICIPAL PIER: PIER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    111. PLAN AND ELEVATION OF HUNTINGTON BEACH MUNICIPAL PIER: PIER MID-SECTION TO END Sheet 2 of 9 (#3253) - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  10. 110. PLAN AND ELEVATION OF HUNTINGTON BEACH MUNICIPAL PIER: PIER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    110. PLAN AND ELEVATION OF HUNTINGTON BEACH MUNICIPAL PIER: PIER APPROACH TO MID-SECTION Sheet 1 of 9 (#3252) - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  11. 124. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: RAMP DETAILS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    124. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: RAMP DETAILS Sheet 6 of 11 (#3278) - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  12. 120. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: LAYOUT OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    120. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: LAYOUT OF EXISTING PIER Sheet 2 of 11 (#3274) - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  13. 123. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: REPAIR DETAILS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    123. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: REPAIR DETAILS Sheet 5 of 11 (#3277) - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  14. 8. GROUND VIEW OF PIER, LOOKING SOUTH FROM BEACH; SHOWING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. GROUND VIEW OF PIER, LOOKING SOUTH FROM BEACH; SHOWING 17TH BENT TO END; NEPTUNE'S GALLEY TO END OF PIER - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  15. 126. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: EXTENSION DETAILS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    126. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: EXTENSION DETAILS Sheet 7 of 11 (#3280) - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  16. 129. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: LIGHTING DIAGRAM. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    129. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: LIGHTING DIAGRAM. Sheet lO of 11 (#3283) - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  17. 130. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: LIGHTING DETAILS. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    130. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: LIGHTING DETAILS. Sheet 11 of 11 (#3284) - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  18. 45. VIEW OF STAIRWAY UP FROM BEACH TO PIER APPROACH, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    45. VIEW OF STAIRWAY UP FROM BEACH TO PIER APPROACH, NORTHWEST SIDE OF PIER, LOOKING NORTHEAST - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  19. 104. VIEW OF NORTHWEST SIDE OF PIER TAKEN FROM BEACH, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    104. VIEW OF NORTHWEST SIDE OF PIER TAKEN FROM BEACH, LOOKING SOUTH. BANDSHELL IS AT RIGHT Photograph #1574-HB. Photographer unknown, c. 1914 - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  20. Terrestrial isopod community as indicator of succession in a peat bog

    PubMed Central

    Antonovi?, Ivan; Brigi?, Andreja; Sedlar, Zorana; Bedek, Jana; Šoštari?, Renata

    2012-01-01

    Abstract Terrestrial isopods were studied in the Dubravica peat bog and surrounding forest in the northwestern Croatia. Sampling was conducted using pitfall traps over a two year period. Studied peat bog has a history of drastically decrease in area during the last five decades mainly due to the process of natural succession and changes in the water level. A total of 389 isopod individuals belonging to 8 species were captured. Species richness did not significantly differ between bog, edge and surrounding forest. High species richness at the bog is most likely the result of progressive vegetation succession, small size of the bog and interspecific relationships, such as predation. With spreading of Molinia grass on the peat bog, upper layers of Sphagnum mosses become less humid and probably more suitable for forest species that slowly colonise bog area. The highest diversity was found at the edge mainly due to the edge effect and seasonal immigration, but also possibly due to high abundance and predator pressure of the Myrmica ants and lycosid spiders at the bog site. The most abundant species were Trachelipus rathkii and Protracheoniscus politus, in the bog area and in the forest, respectively. Bog specific species were not recorded and the majority of the species collected belong to the group of tyrphoneutral species. However, Hyloniscus adonis could be considered as a tyrphoxenous species regarding its habitat preferences. Most of collected isopod species are widespread eurytopic species that usually inhabit various habitats and therefore indicate negative successive changes or degradation processes in the peat bog. PMID:22536107

  1. The Global Diversity of Parasitic Isopods Associated with Crustacean Hosts (Isopoda: Bopyroidea and Cryptoniscoidea)

    PubMed Central

    Williams, Jason D.; Boyko, Christopher B.

    2012-01-01

    Parasitic isopods of Bopyroidea and Cryptoniscoidea (commonly referred to as epicarideans) are unique in using crustaceans as both intermediate and definitive hosts. In total, 795 epicarideans are known, representing ?7.7% of described isopods. The rate of description of parasitic species has not matched that of free-living isopods and this disparity will likely continue due to the more cryptic nature of these parasites. Distribution patterns of epicarideans are influenced by a combination of their definitive (both benthic and pelagic species) and intermediate (pelagic copepod) host distributions, although host specificity is poorly known for most species. Among epicarideans, nearly all species in Bopyroidea are ectoparasitic on decapod hosts. Bopyrids are the most diverse taxon (605 species), with their highest diversity in the North West Pacific (139 species), East Asian Sea (120 species), and Central Indian Ocean (44 species). The diversity patterns of Cryptoniscoidea (99 species, endoparasites of a diverse assemblage of crustacean hosts) are distinct from bopyrids, with the greatest diversity of cryptoniscoids in the North East Atlantic (18 species) followed by the Antarctic, Mediterranean, and Arctic regions (13, 12, and 8 species, respectively). Dajidae (54 species, ectoparasites of shrimp, mysids, and euphausids) exhibits highest diversity in the Antarctic (7 species) with 14 species in the Arctic and North East Atlantic regions combined. Entoniscidae (37 species, endoparasites within anomuran, brachyuran and shrimp hosts) show highest diversity in the North West Pacific (10 species) and North East Atlantic (8 species). Most epicarideans are known from relatively shallow waters, although some bopyrids are known from depths below 4000 m. Lack of parasitic groups in certain geographic areas is likely a sampling artifact and we predict that the Central Indian Ocean and East Asian Sea (in particular, the Indo-Malay-Philippines Archipelago) hold a wealth of undescribed species, reflecting our knowledge of host diversity patterns. PMID:22558143

  2. Distribution and diversity patterns of asellote isopods (Crustacea) in the deep Norwegian and Greenland Seas

    NASA Astrophysics Data System (ADS)

    Svavarsson, Jörundur; Brattegard, Torleiv; Strömberg, Jarl-Ove

    Distribution and diversity patterns of asellote isopods (Crustacea) of the deep Norwegian and Greenland Seas are described. The asellotes show the same pattern of rapid faunal change across the upper continental slope as commonly described elsewhere. Here the rate of species replacement is maximum at depths of 800-1000m, but decreases towards greater depths. The distribution of the asellotes shows some correlations to the distribution of sediment types. Species diversity is maximum at 800m and decreases with depth. The species diversity pattern is related here to heterogeneity of the sediments and different species immigration rates into shallow and deep Arctic waters.

  3. "Beach-Ball" Robotic Rovers

    NASA Technical Reports Server (NTRS)

    Smyth, David E.

    1995-01-01

    Robotic vehicles resembling large beach balls proposed for carrying scientific instruments. Conceived for use in exploring planet Mars, also useful on Earth to carry meteorological or pollution-monitoring equipment to remote locations across rough terrain and even across water. Each vehicle features approximately spherical balloonlike outer shell inflated to suitable pressure. Three diametral tethers approximately perpendicular to each other attached to shell. Control box moves itself along tethers to shift center of gravity, causing vehicle to roll. Alternatively, instead of shell, structure of approximately spherical outline made of twisted rods; of course, not suitable for traversing water or thick vegetation.

  4. PREDICTING BACTERIAL CONCENTRATION ON THE NATION'S BEACHES

    EPA Science Inventory

    A classical example of the failure of institutions and environmental technology to protect the nation's aesthetic, recreational, and public health values is represented by the July-August, 1999 Huntington Beach, California beach closure. This multi-million dollar regional public ...

  5. A Study of Sandy Beach Zonation.

    ERIC Educational Resources Information Center

    Alexander, Steve K.

    1991-01-01

    Describes the study of sandy beach zonations as a seashore activity for either high school or lower-level college courses in biology, ecology, or marine biology. Students first draw a profile of a beach scene and then collect specimens from the zones of the shore. In a laboratory, students identify their specimens and relate them to the beach…

  6. Effects of beach cast cleaning on beach quality, microbial food web, and littoral macrofaunal biodiversity

    NASA Astrophysics Data System (ADS)

    Malm, Torleif; RÃ¥berg, Sonja; Fell, Sabine; Carlsson, Per

    2004-06-01

    At the end of the summer, drifting filamentous red algae cover shallow bottoms and accumulate in huge cast walls on the open shores of the non-tidal central Baltic Sea. The hypotheses that beach cleaning increases water clarity, decreases the organic content of the sand, and increases the species diversity in the shallow zone closest to the shore, were tested through field investigations and experiments. Cleaned shorelines were compared with un-cleaned shorelines at two sites with different intensity of beach cleaning in a rural area of SE Sweden. The results show that water clarity was significantly increased off the intensively cleaned beach but not off the moderately cleaned one. Similarly, the total leakage of nitrogenous compounds decreased off the intensively cleaned beach, but not off the moderately cleaned. The organic content of the sand was lower on both cleaned beaches compared with nearby un-cleaned beaches. The total animal biomass was significantly lower on the intensively cleaned beach compared with the un-cleaned beach, but the moderately cleaned beach gave no such effect. The difference in biodiversity and community structure between cleaned and un-cleaned beaches was insignificant. The most obvious difference in species composition was a much higher number of planktivore opossum shrimps of the genus Mysis and Praunus on the un-cleaned beaches. The bacterial production and the amount of ciliates larger than 20 mm were also higher on un-cleaned beaches, indicating that the microbial food web off the un-cleaned beaches is stimulated by the discharge of decomposing algal material. The conclusion of the study is that mechanical cleaning reduces the organic content of the beach sand and may change the water quality and microbial production, but the effect on the macrofaunal biodiversity is insignificant.

  7. Dynamics of Shengjini beach (Albania)

    NASA Astrophysics Data System (ADS)

    Gashi, Ferim; Nikolli, Pal

    2015-04-01

    Dynamics of Shengjini beach (Albania) Pal Nikolli , Ferim GASHI Through archaeological and historical data, presentations of ancient topographic, cartographic materials (topographic maps obtained at different periods from 1870 to 1990), aerial photographs (2007), satellite images (2014) and direct measurements, paper defines and analyzes the position of the coastline of Shengjini beach (Lezha) from century XVI until today. The coastline of the Shengjini city (port) to Drin River estuary is oriented north-south direction and is approximately 10.5 km long. This part of the coast is sandy and sediment comes mainly from the River Drin and distributed by currents along the coast. In this paper are make provision for the position of the coastline in the future and analyzed the possibilities of human intervention in the coastal environment , etc. This work forms the basis for the issuance of necessary data required for various projections at the coastal environment Shëngjini. Results of this study will have a significant impact on state policies for integrated management of the coastal zone in the study and development of tourism. Key words: GIS, Remonte Sennsing, cartography, management of coastal zone, tourism, environment.

  8. Uptake and toxicity of Cd, Cu and Pb mixtures in the isopod Asellus aquaticus from waterborne exposure.

    PubMed

    Van Ginneken, M; De Jonge, M; Bervoets, L; Blust, R

    2015-12-15

    The present study evaluated interactions of waterborne Cd, Cu and Pb mixtures on metal uptake rates in the isopod Asellus aquaticus and related this to mixture effects on toxicity. Secondly, it was assessed whether observed mixture effects were better related to isopod body concentrations compared to exposure concentrations. Isopods were exposed for 10 days to single, binary and tertiary mixtures including five different concentrations of Cd (0.107 to 277 ?g L(-1)), Cu (3.35 to 2117 ?g L(-1)) and Pb (0.782 to 443 ?g L(-1)). Mortality was assessed every day while isopod body concentrations, growth (biomass) and energy reserves (glycogen, lipid and protein reserves) were assessed at the end of the experiment. Synergistic interactions of combined Cd and Pb exposure on Cd and Pb uptake as well as on growth rates and mortality rates were observed. Mixture effects of combined Cd and Pb exposure on toxicity endpoints were directly related to increased Cd uptake in the Cd+Pb treatment. No mixture interactions of Cu on Cd or Pb uptake (and vice versa), nor on toxicity endpoints were observed. All toxicity endpoints were related to body concentrations. However, mixture effects disappeared when growth and mortality rates were expressed on body concentrations instead of exposure concentrations. By combining information of mixture effects on metal uptake with mixture toxicity data, the present study provides more insight in the way metal mixtures interfere with aquatic organisms and how they can induce toxic effects. PMID:26282750

  9. Isolation, characterization and PCR multiplexing of microsatellite loci for two sub-species of terrestrial isopod Porcellio dilatatus (Crustacea, Oniscidea).

    PubMed

    Michaud, Caroline; Chupeau, Cassandre; Bech, Nicolas; Thierry, Magali; Sicard, Mathieu; Greve, Pierre; Beltran-Bech, Sophie

    2016-04-01

    Several microsatellite markers have already been developed for different terrestrial isopod species such as Armadillidium vulgare, A. nasatum and Porcellionides pruinosus. In all these species, the endosymbiont Wolbachia has a feminizing effect that generates a female bias in sex ratio and reduces the number of reproductive males. Thus this can potentially decrease the genetic diversity of host populations. However, in some other isopod species, Wolbachia induces cytoplasmic incompatibility (CI); the most commonly described effect of Wolbachia in arthropods. The CI by rendering some crossings incompatible can reduce the gene flow and strengthen genetic differentiation between isopod populations. To date, the influence of Wolbachia inducing CI on population structure of terrestrial isopods has never been investigated. In this study, we developed 10 polymorphic microsatellite markers shared by two sub-species of Porcellio dilatatus. Crossings between the two sub-species are partially incompatible due to two CI-inducing Wolbachia strains. These new microsatellite markers will allow us to investigate the effect of CI on host genetic differentiation in this species complex. PMID:26943350

  10. Draft Genome Sequence of "Candidatus Hepatoplasma crinochetorum" Ps, a Bacterial Symbiont in the Hepatopancreas of the Terrestrial Isopod Porcellio scaber.

    PubMed

    Collingro, Astrid; Kostanjšek, Rok; Toenshoff, Elena R; Schulz, Frederik; Schuster, Lisa; Domann, Daryl; Horn, Matthias

    2015-01-01

    "Candidatus Hepatoplasma crinochetorum" Ps is an extracellular symbiont residing in the hepatopancreas of the terrestrial isopod Porcellio scaber. Its genome is highly similar to that of the close relative "Ca. Hepatoplasma crinochetorum" Av from Armadillidium vulgare. However, instead of a clustered regularly interspaced short palindromic repeat (CRISPR)-Cas system, it encodes a type I restriction modification system. PMID:26272556

  11. First recorded cave-dwelling terrestrial isopods (Isopoda: Oniscidea) in Iran with a description of a new species .

    PubMed

    Kashani, Ghasem M; Malekhosseini, Mohammad-Javad; Sadeghi, Saber

    2013-01-01

    Cave-dwelling terrestrial isopods from the province of Kohgiluyeh and Boyerahmad, southwestern Iran, are reported here. These include three accidental and one troglobitic species namely Protracheoniscus gakalicus n. sp., which is also the first recorded troglobitic species from the genus Protracheoniscus. The new species is readily distinguished by the lack of eyes and pigmentation. PMID:25277941

  12. Microsatellite Development and First Population Size Estimates for the Groundwater Isopod Proasellus walteri

    PubMed Central

    Capderrey, Cécile; Kaufmann, Bernard; Jean, Pauline; Malard, Florian; Konecny-Dupré, Lara; Lefébure, Tristan; Douady, Christophe J.

    2013-01-01

    Effective population size (Ne) is one of the most important parameters in, ecology, evolutionary and conservation biology; however, few studies of Ne in surface freshwater organisms have been published to date. Even fewer studies have been carried out in groundwater organisms, although their evolution has long been considered to be particularly constrained by small Ne. In this study, we estimated the contemporary effective population size of the obligate groundwater isopod: Proaselluswalteri (Chappuis, 1948). To this end, a genomic library was enriched for microsatellite motifs and sequenced using 454 GS-FLX technology. A total of 54,593 reads were assembled in 10,346 contigs or singlets, of which 245 contained candidate microsatellite sequences with suitable priming sites. Ninety-six loci were tested for amplification, polymorphism and multiplexing properties, of which seven were finally selected for Ne estimation. Linkage disequilibrium and approximate Bayesian computation methods revealed that Ne in this small interstitial groundwater isopod could reach large sizes (> 585 individuals). Our results suggest that environmental conditions in groundwater, while often referred to as extreme, are not necessarily associated with small Ne. PMID:24086709

  13. Hierarchical organization of the cuticle of the subsocial desert isopod, Hemilepistus reaumurii.

    PubMed

    Ayari, Anas; Raimond, Maryline; Souty-Grosset, Catherine; Nasri-Ammar, Karima

    2016-02-01

    The crustacean cuticle is a hierarchically organised material which provides protection and sites for muscle attachment. The physical properties of this exoskeleton envelope are adapted to the function and the eco-physiological requirements of the species. This paper aimed to study, using the TEM, the structure of the tubercle and the tergite cuticle of the arid species Hemilepistus reaumurii in a comparison with a subhumid isopod in order to relate some peculiar features to an adaptive process to environmental constraints. Results showed that wild H. reaumurii cuticles were twice as thick in comparison with Porcellio variabilis which is a subhumid zone isopod. It is suggested therefore that the thick cuticle of wild H. reaumurii can be an adaptation to terrestrial life and a protection against osmotic stress and water loss in an arid environment. In addition the inside of the tubercle showed a high number of lipid droplets stacked into an adipose tissue which suggest that tubercles were used for storage for nutritive material in wild H. reaumurii. PMID:26687417

  14. Environmental- and growth stage-related differences in the susceptibility of terrestrial isopods to UV radiation.

    PubMed

    Morgado, Rui; Ferreira, Nuno G C; Tourinho, Paula; Ribeiro, Fabianne; Soares, Amadeu M V M; Loureiro, Susana

    2013-09-01

    Global environmental changes are nowadays one of the most important issues affecting terrestrial ecosystems. One of its most significant expressions is the increasing ultraviolet radiation (UVR) arising from the human-induced depletion in ozone layer. Therefore, to investigate the effects of UVR on the terrestrial isopod Porcellionides pruinosus a multiple biomarker approach was carried out. Two experiments were performed in order to analyze the importance of the exposure environment and the growth stage on the UV-induced damages. First, adult individuals were exposed to UVR in three exposure environments (soil, soil with leaves, and plaster). Thereafter, three growth stages using soil as the exposure condition were tested. Integrated biomarker responses (IBR) suggested that UV effects were higher in plaster, and mostly identified by changes in acetylcholinesterase and glutathione-S-transferases activities, lipid peroxidation rates, and total energy available. The effects in soil and soil with leaves were not so clear. In the growth stages' experiment, juveniles and pre-adults were found to be more affected than adults, with the greatest differences between irradiated and non-irradiated isopods occurring in energy-related parameters. Our findings suggest that soil surface-living macrofauna may be prone to deleterious effects caused by UVR, highlighting the importance of taking the media of exposure and growth stage in account. PMID:23899792

  15. Morphological description of bacterial infection of digestive glands in the terrestrial isopod porcellio scaber (Isopoda, crustacea)

    PubMed

    Drobne; Strus; Znidarsic; Zidar

    1999-01-01

    Morphological studies of the hepatopancreas of the terrestrial isopod Porcellio scaber revealed bacterial infection. The percentage of infected animals collected from the same site varied from 0 to 10% during the 4 years of study. Transmission electron microscopy, scanning electron microscopy, and light microscopy revealed that infected glands differed from those in healthy isopods. The most prominent sign was white spots between 100 and 200 &mgr;m in diameter along the entire gland. These spots were aggregations of vacuoles in the cells that were densely filled with bacteria in different phases of the developmental cycle that included the formation of small, dense, rod-shaped infective bacteria and much larger spherical multiplying cells filled with aggregates of polysomes and a chromatin network. Occasionally, large sphericles were filled with homogeneous electron-dense material. Bacteria were not observed in the cell nucleus. Small vacuoles of less than 5 &mgr;m were filled predominately with spherical bacteria but rod-shaped forms were also present in large numbers. Larger vacuoles of 10 to 20 &mgr;m in the main were densely filled with rod-shaped bacteria. According to the literature on the morphological characteristics of bacteria infecting invertebrates, those described in our study would be classified in the genus Rickettsiella. However, most recent investigations show that besides morphological investigations, genetic ones are also needed to define the taxonomic position of bacteria that infect invertebrates. Copyright 1999 Academic Press. PMID:9878297

  16. Body shape in terrestrial isopods: A morphological mechanism to resist desiccation?

    PubMed

    Broly, Pierre; Devigne, Cédric; Deneubourg, Jean-Louis

    2015-11-01

    Woodlice are fully terrestrial crustaceans and are known to be sensitive to water loss. Their half-ellipsoidal shapes represent simple models in which to investigate theoretical assumptions about organism morphology and rates of exchange with the environment. We examine the influence of surface area and mass on the desiccation rates in three eco-morphologically different species of woodlice: Oniscus asellus, Porcellio scaber, and Armadillidium vulgare. Our analysis indicates that the rate of water loss of an individual depends on both the initial weight and the body surface area. Interspecific and intraspecific analyses show that the mass-specific water loss rate of a species decreases along with the ratio of surface area to volume. In particular, we show that body shape explains the difference in mass-specific water loss rates between A. vulgare and P. scaber. This observation also explains several known ecological patterns, for example, the distribution and survivorship of individuals. However, in addition to body size and shape, water loss in terrestrial isopods depends also on the coefficient of permeability (i.e., a measure of water loss rate per surface unit), which is high in O. asellus and lower (and at similar levels) in P. scaber and A. vulgare. We discuss morphological, physiological, and behavioral aspects of water loss avoidance in terrestrial isopods. PMID:26289755

  17. Mitochondrial genome haplotype hypervariation within the isopod parasitic nematode Thaumamermis cosgrovei.

    PubMed

    Tang, Sha; Hyman, Bradley C

    2007-06-01

    Characterization of mitochondrial genomes from individual Thaumamermis cosgrovei nematodes, obligate parasites of the isopod Armadillidium vulgare, revealed that numerous mtDNA haplotypes, ranging in size from 19 to 34 kb, are maintained in several spatially separated isopod populations. The magnitude and frequency of conspecific mtDNA size variation is unprecedented among all studied size-polymorphic metazoan mitochondrial genomes. To understand the molecular basis of this hypervariation, complete nucleotide sequences of two T. cosgrovei mtDNA haplotypes were determined. A hypervariable segment, residing between the atp6 and rrnL genes, contributes exclusively to T. cosgrovei mtDNA size variation. Within this region, mtDNA coding genes and putative nonfunctional sequences have accumulated substitutions and are duplicated and rearranged to varying extents. Hypervariation at this level has enabled a first insight into the life history of T. cosgrovei. In five A. vulgare hosts infected with multiple nematodes, four carried nematodes with identical mtDNA haplotypes, suggesting that hosts may become infected by ingesting a recently hatched egg clutch or become parasitized by individuals from the same brood prior to dispersal of siblings within the soil. PMID:17435228

  18. The observed relationship between wave conditions and beach response, Ocean Beach, San Francisco, CA

    USGS Publications Warehouse

    Hansen, J.E.; Barnard, P.L.

    2009-01-01

    Understanding how sandy beaches respond to storms is critical for effective sediment management and developing successful erosion mitigation efforts. However, only limited progress has been made in relating observed beach changes to wave conditions, with one of the major limiting factors being the lack of temporally dense beach topography and nearshore wave data in most studies. This study uses temporally dense beach topographic and offshore wave data to directly link beach response and wave forcing with generally good results. Ocean Beach is an open coast high-energy sandy beach located in San Francisco, CA, USA. From April 2004 through the end of 2008, 60 three-dimensional topographic beach surveys were conducted on approximately a monthly basis, with more frequent “short-term surveys during the winters of 2005-06 and 2006-07. Shoreline position data from the short-term surveys show good correlation with offshore wave height, period, and direction averaged over several days prior to the survey (mean R*=0.54 for entire beach). There is, however, considerable alongshore variation in model performance, with R- values ranging from 0.81 to 0.19 for individual sections of the beach. After wave height, the direction of wave approach was the most important factor in determining the response of the shoreline, followed by wave period. Our results indicate that an empirical predictive model of beach response to wave conditions at Ocean Beach is possible with frequent beach mapping and wave data, and that such a model could be useful to coastal managers. 

  19. A hybrid beach morphology model applied to a high energy sandy beach

    NASA Astrophysics Data System (ADS)

    Karunarathna, Harshinie; Ranasinghe, Roshanka; Reeve, Dominic E.

    2015-11-01

    In this paper, the application of a hybrid coastal morphodynamic model to forecast inter-annual beach change is discussed through the prediction of beach change in a high energy sandy beach over a period of 5 years. The modelling approach combines a `reduced-physics' formulation with a data-driven approach through an inverse technique to form the hybrid coastal morphodynamic model. The beach considered for the demonstration of the model is the Narrabeen Beach, which is a dynamic sand beach located in New South Wales, Australia. Despite its simplicity, we find that the model is able to capture beach change at Narrabeen Beach at inter-annual timescales with root mean square error between measured and computed beach profiles less than 0.4 m on average. Even though the model is used to forecast inter-annual beach change in this study, its ability to predict beach change is not limited to that timescale but depends on the frequency of historic beach profile measurements available to determine key unknown parameters of the model. Also, the length of profile forecasts largely depends on the length of available historic measurements where longer data sets allow longer predictions within a range of beach behaviour contained in the observations. The ability of the model to reliably forecast coastal change at inter-annual and potentially at other timescales, and its high efficiency make it possible to be used in providing multiple simulations required for probabilistic coastal change forecasts which will be very useful for coastal management purposes.

  20. Horseshoe crab (Limulus polyphemus) reproductive activity on Delaware Bay beaches: Interactions with beach characteristics

    USGS Publications Warehouse

    Smith, D.R.; Pooler, P.S.; Loveland, R.E.; Botton, M.L.; Michels, S.F.; Weber, R.G.; Carter, Daniel B.

    2002-01-01

    We used results from a survey of horseshoe crab reproductive activity that was conducted in 1999 throughout Delaware Bay to examine the relationship between estimates of spawning females and egg deposition and analyze how that relationship varies with geography, time within a spawning season, beach morphology, and wave energy. We found that beach morphology and wave energy interacted with density of spawning females to explain variation in the density and distribution of eggs and larvae. For example, the quantity of eggs in surface sediment (i.e., eggs that are potentially available to foraging shorebirds) was associated with the density of spawning females, beach morphology, and wave energy. The association between beach morphology and live eggs in surface sediment was strong especially in late May (Percent Reduction in Error = 86% from regression tree model) where egg density was an order of magnitude higher on beaches <15 m wide (3.38*105 m-2; 90% CI: 2.29*105, 4.47*105) compared to wider beaches (1.49*104 m-2; 90% CI: 4.47*103, 2.53*104). Results also indicate that, among bay-front beaches, horseshoe crabs prefer to spawn on narrow beaches, possibly because of reduced wave energy. At peak periods of spawning activity, density of spawning females was inversely related to foreshore width on mid-latitude beaches within Delaware Bay (t = -2.68, 7 df, p = 0.03). Because the distribution of eggs across the foreshore varied with beach morphology and widened as the spawning season progressed, methods used to sample eggs need to be robust to variation in beach morphology and applicable regardless of when the samples are taken. Because beach morphology and wave energy were associated with the quantity of eggs in surface sediment, certain beach types may be critical to the conservation of shorebird foraging habitat.

  1. Morphodynamics of a mesotidal rocky beach: Palmeras beach, Gorgona Island National Natural Park, Colombia

    NASA Astrophysics Data System (ADS)

    Gómez-García, A. M.; Bernal, G. R.; Osorio, A. F.; Botero, V.

    2014-10-01

    The response of a rocky beach to different possible combinations of hydrodynamic conditions (tides, waves, oceanic currents) has been little studied. In this work, the morphodynamic response to different hydrodynamic forcing is evaluated from sedimentological and geomorphological analysis in seasonal and medium term (19 years) scale in Palmeras beach, located in the southwest of Gorgona Island National Natural Park (NNP), a mesotidal rocky island on the Colombian Pacific continental shelf. Palmeras is an important nesting area of two types of marine turtles, with no anthropogenic stress. In the last years, coastal erosion has reduced the beach width, restricting the safe areas for nesting and conservation of these species. Until now, the sinks, sources, reservoirs, rates, and paths of sediments were unknown, as well as their hydrodynamic forcing. The beach seasonal variability, from October 2010 to August 2012, was analyzed based on biweekly or monthly measurements of five beach profiles distributed every 200 m along the 1.2 km of beach length. The main paths for sediment transport were defined from the modeling of wave currents with the SMC model (Coastal Modeling System), as well as the oceanic currents, simulated for the dry and wet seasons of 2011 using the ELCOM model (Estuary and Lake COmputer Model). Extreme morphologic variations over a time span of 19 years were analyzed with the Hsu and Evans beach static equilibrium parabolic model, from one wave diffraction point which dominates the general beach plan shape. The beach lost 672 m3/m during the measuring period, and erosional processes were intensified during the wet season. The beach trends responded directly to a wave mean energy flux change, resulting in an increase of up to 14 m in the width northward and loss of sediments in the beach southward. This study showed that to obtain the integral morphodynamic behavior of a rocky beach it is necessary to combine information of hydrodynamic, sedimentology and geomorphology in different time scales.

  2. The Different Faces of San Francisco's Ocean Beach: Analyzing Sand Size and Beach Shape

    NASA Astrophysics Data System (ADS)

    Grove, K.; Labit, R.; Lui, S.; Rodriquez, I.; Yi, C.; Yu, M.

    2004-12-01

    Ocean Beach is located along the western edge of San Francisco adjacent to the Pacific Ocean. Erosion along the southern part of the beach is threatening a nearby highway and water treatment plant. To better understand this beach and the processes that form it, our SF-ROCKS research group collected data from seven locations along its length. We used an auto-level surveying instrument to measure beach profiles and we collected sand samples that were measured using sieves and a sieve shaker. We plotted profiles and grain-size data using Excel and Surfer software. The sediment is mostly fine sand, and the means of all samples range between 0.19-0.26 mm. There may be little variation along the beach because only small sand grains have survived the long journey from their Sierra Nevada source. Profile shape does vary along the beach. The profile at the northern end is about three times wider than the profile at the southern end. The northern profile is flatter overall, but all profiles had a steep beach face in August, when the data were collected. The differences in beach profiles may be related to position relative to the offshore bar, which appears to provide sand to the northern part of the beach. Our group will collect more data in November to see what changes have occurred after the large-wave season has begun. We will use Surfer software to compare summer and fall profiles, to see where sediment has been added and where sediment has been removed. We will also compare our results to the data collected by Dr. Patrick Barnard and his research group at the U.S. Geological Survey, who are using an All-Terrain Vehicle to measure beach profiles and a camera to measure sediment size. We will use our analysis of beach variations to make recommendations for reducing beach erosion.

  3. What Is the Impact of Beach Debris?

    ERIC Educational Resources Information Center

    Fortner, Rosanne W.; Jax, Dan

    2003-01-01

    Presents a marine education activity. Students construct a web of changes that shows potential problems caused by solid waste on beaches. They then determine whether each change is an increase or a decrease from previous conditions. (Author/SOE)

  4. Sea level anomalies exacerbate beach erosion

    NASA Astrophysics Data System (ADS)

    Theuerkauf, Ethan J.; Rodriguez, Antonio B.; Fegley, Stephen R.; Luettich, Richard A.

    2014-07-01

    Sea level anomalies are intra-seasonal increases in water level forced by meteorological and oceanographic processes unrelated to storms. The effects of sea level anomalies on beach morphology are unknown but important to constrain because these events have been recognized over large stretches of continental margins. Here, we present beach erosion measurements along Onslow Beach, a barrier island on the U.S. East Coast, in response to a year with frequent sea level anomalies and no major storms. The anomalies enabled extensive erosion, which was similar and in most places greater than the erosion that occurred during a year with a hurricane. These results highlight the importance of sea level anomalies in facilitating coastal erosion and advocate for their inclusion in beach-erosion models and management plans. Sea level anomalies amplify the erosive effects of accelerated sea level rise and changes in storminess associated with global climate change.

  5. Plastics and beaches: a degrading relationship.

    PubMed

    Corcoran, Patricia L; Biesinger, Mark C; Grifi, Meriem

    2009-01-01

    Plastic debris in Earth's oceans presents a serious environmental issue because breakdown by chemical weathering and mechanical erosion is minimal at sea. Following deposition on beaches, plastic materials are exposed to UV radiation and physical processes controlled by wind, current, wave and tide action. Plastic particles from Kauai's beaches were sampled to determine relationships between composition, surface textures, and plastics degradation. SEM images indicated that beach plastics feature both mechanically eroded and chemically weathered surface textures. Granular oxidation textures were concentrated along mechanically weakened fractures and along the margins of the more rounded plastic particles. Particles with oxidation textures also produced the most intense peaks in the lower wavenumber region of FTIR spectra. The textural results suggest that plastic debris is particularly conducive to both chemical and mechanical breakdown in beach environments, which cannot be said for plastics in other natural settings on Earth. PMID:18834997

  6. Macrodebris and microplastics from beaches in Slovenia.

    PubMed

    Laglbauer, Betty J L; Franco-Santos, Rita Melo; Andreu-Cazenave, Miguel; Brunelli, Lisa; Papadatou, Maria; Palatinus, Andreja; Grego, Mateja; Deprez, Tim

    2014-12-15

    The amount of marine debris in the environment is increasing worldwide, which results in an array of negative effects to biota. This study provides the first account of macrodebris on the beach and microplastics in the sediment (shoreline and infralittoral) in relation to tourism activities in Slovenia. The study assessed the quality and quantity of macrodebris and the quality, size and quantity of microplastics at six beaches, contrasting those under the influences of tourism and those that were not. Beach cleanliness was estimated using the Clean Coast Index. Tourism did not seem to have an effect on macrodebris or microplastic quantity at beaches. Over 64% of macrodebris was plastic, and microplastics were ubiquitous, which calls for classification of plastics as hazardous materials. Standard measures for marine debris assessment are needed, especially in the form of an all-encompassing debris index. Recommendations for future assessments are provided for the Adriatic region. PMID:25440193

  7. Salinity and groundwater flow below beaches

    NASA Astrophysics Data System (ADS)

    Evans, T. B.; Wilson, A. M.; Moore, W. S.

    2013-12-01

    High rates of exchange between seawater and fresh groundwater in beach sediments drive significant chemical reactions, but the groundwater flow that controls this is poorly understood. Current conceptual models for groundwater flow in beaches highlight an upper saline plume, which is separated from the traditional freshwater-saltwater interface by a zone of brackish to fresh groundwater discharge. The lack of an upper saline plume at our study site led us to ask whether the plume exists in all beaches and what hydrogeological features control its formation. We used variable-density, saturated-unsaturated, transient groundwater flow models to investigate the geometry of the freshwater-saltwater interface in beaches with slopes varying from 0.1 to 0.01. We also varied hydraulic conductivity, dispersivity, tidal amplitude, inflow of fresh groundwater and precipitation. All models showed that a salinity gradient developed between the fresh groundwater and seawater in the intertidal zone, but the magnitude of the gradient was variable. The hydraulic conductivity was an important control on the development of an upper saline plume. A hydraulic conductivity of 100 m/d allowed the formation of an upper saline plume in every beach slope. No upper saline plumes formed in any beach with hydraulic conductivities less than 10 m/d. The slope of the beach was also a significant control. In models using a representative hydraulic conductivity of 10 m/d, the upper saline plume only formed in beaches with a slope of 0.5 or greater. The salinity of brackish groundwater that discharges seaward of the upper saline plume was inversely proportional to the input of fresh groundwater. Prior studies of groundwater flow and salinity in beaches have used very small dispersivities, but we found that the upper saline plume becomes much less distinct when larger dispersivities are used. Real beaches are highly mixed environments and the appropriate magnitude of dispersivity remains unclear. Our results suggest that upper saline plumes may not form in beaches of the U.S. Southeast, which are characterized by fine-grained sediment and moderate slopes. The concentration gradient between the upper saline plume and adjacent groundwater discharge zone increased with decreasing longitudinal dispersivity.

  8. Nowcasting Beach Advisories at Ohio Lake Erie Beaches

    USGS Publications Warehouse

    Francy, Donna S.; Darner, Robert A.

    2007-01-01

    Data were collected during the recreational season of 2007 to test and refine predictive models at three Lake Erie beaches. In addition to E. coli concentrations, field personnel collected or compiled data for environmental and water-quality variables expected to affect E. coli concentrations including turbidity, wave height, water temperature, lake level, rainfall, and antecedent dry days and wet days. At Huntington (Bay Village) and Edgewater (Cleveland) during 2007, the models provided correct responses 82.7 and 82.1 percent of the time; these percentages were greater than percentages obtained using the previous day?s E. coli concentrations (current method). In contrast, at Villa Angela during 2007, the model provided correct responses only 61.3 percent of the days monitored. The data from 2007 were added to existing datasets and the larger datasets were split into two (Huntington) or three (Edgewater) segments by date based on the occurrence of false negatives and positives (named ?season 1, season 2, season 3?). Models were developed for dated segments and for combined datasets. At Huntington, the summed responses for separate best models for seasons 1 and 2 provided a greater percentage of correct responses (85.6 percent) than the one combined best model (83.1 percent). Similar results were found for Edgewater. Water resource managers will determine how to apply these models to the Internet-based ?nowcast? system for issuing water-quality advisories during 2008.

  9. Monitoring beach changes using GPS surveying techniques

    USGS Publications Warehouse

    Morton, Robert; Leach, Mark P.; Paine, Jeffrey G.; Cardoza, Michael A.

    1993-01-01

    The adaptation of Global Positioning System (GPS) surveying techniques to beach monitoring activities is a promising response to this challenge. An experiment that employed both GPS and conventional beach surveying was conducted, and a new beach monitoring method employing kinematic GPS surveys was devised. This new method involves the collection of precise shore-parallel and shore-normal GPS positions from a moving vehicle so that an accurate two-dimensional beach surface can be generated. Results show that the GPS measurements agree with conventional shore-normal surveys at the 1 cm level, and repeated GPS measurements employing the moving vehicle demonstrate a precision of better than 1 cm. In addition, the nearly continuous sampling and increased resolution provided by the GPS surveying technique reveals alongshore changes in beach morphology that are undetected by conventional shore-normal profiles. The application of GPS surveying techniques combined with the refinement of appropriate methods for data collection and analysis provides a better understanding of beach changes, sediment transport, and storm impacts.

  10. Spectroscopic parameters of the cuticle and ethanol extracts of the fluorescent cave isopod Mesoniscusgraniger (Isopoda, Oniscidea).

    PubMed

    Giurginca, Andrei; Šustr, Vladimír; Tajovský, Karel; Giurginca, Maria; Matei, Iulia

    2015-01-01

    The body surface of the terrestrial isopod Mesoniscusgraniger (Frivaldsky, 1863) showed blue autofluorescence under UV light (330-385 nm), using epifluorescence microscopy and also in living individuals under a UV lamp with excitation light of 365 nm. Some morphological cuticular structures expressed a more intense autofluorescence than other body parts. For this reason, only the cuticle was analyzed. The parameters of autofluorescence were investigated using spectroscopic methods (molecular spectroscopy in infrared, ultraviolet-visible, fluorescence, and X-ray fluorescence spectroscopy) in samples of two subspecies of Mesoniscusgraniger preserved in ethanol. Samples excited by UV light (from 350 to 380 nm) emitted blue light of wavelengths 419, 420, 441, 470 and 505 nm (solid phase) and 420, 435 and 463 (ethanol extract). The results showed that the autofluorescence observed from living individuals may be due to some ?-carboline or coumarin derivatives, some crosslinking structures, dityrosine, or due to other compounds showing similar excitation-emission characteristics. PMID:26261444

  11. Diel infestation dynamics of gnathiid isopod larvae parasitic on Caribbean reef fish

    NASA Astrophysics Data System (ADS)

    Sikkel, Paul C.; Schaumburg, Collin S.; Mathenia, Jeremy K.

    2006-11-01

    Infestation dynamics of parasitic gnathiid isopods on Caribbean reefs were studied throughout the 24-h diel cycle. Gnathiid infestation on caged longfin damselfish ( Stegastes diencaeus) peaked strongly at dawn, remained low during the remainder of the day, and increased again at night until about midnight. Gnathiids were less abundant during the pre-dawn period. Peak loads on fish retrieved at dawn were the highest reported in any study thus far. The dawn peak consisted almost exclusively of individuals from the smallest size class, whereas nocturnal activity consisted almost exclusively of individuals of the largest size class. Because of the high rates of infestation at night and dawn, and the high variation in parasite loads on fish collected during that time, reduction of parasite infestation may play an important role in the selection of nocturnal and crepuscular shelter holes and settlement sites by reef fishes.

  12. Peripheral targets of centrally located putative accessory neurons of MRO in the isopod Ligia exotica.

    PubMed

    Hama, Noriyuki; Okada, Yoshinori; Pollák, Edit; Molnár, László; Niida, Akiyoshi

    2003-08-01

    The three centrally located putative accessory neurons of the muscle receptor organ (MRO) of the isopod Ligia exotica were identified to the third segmental nerve (N3) of the thoracic ganglion by backfilling with Lucifer Yellow. These neurons were then studied intracellularly and extracellularly to determine whether they suppressed the stretch-activated responses of thoracic stretch receptors. Intracellular injection of depolarizing currents into these three putative accessory neurons revealed that only neuron #3 had an inhibitory effect, suggesting that it is an inhibitory accessory neuron related to thoracic stretch receptors. We searched for the peripheral targets of neurons #1 and #2 by intracellular filling with Lucifer Yellow or by recording of junctional potentials in extensor muscles, and show that they are motor neurons that innervate the deep extensor and superficial extensor muscles, respectively. PMID:12819268

  13. Simulating population recovery of an aquatic isopod: Effects of timing of stress and landscape structure.

    PubMed

    Galic, Nika; Baveco, Hans; Hengeveld, Geerten M; Thorbek, Pernille; Bruns, Eric; van den Brink, Paul J

    2012-04-01

    In agroecosystems, organisms may regularly be exposed to anthropogenic stressors, e.g. pesticides. Species' sensitivity to stress depends on toxicity, life-history, and landscape structure. We developed an individual-based model of an isopod, Asellus aquaticus, to explore how timing of stress events affects population dynamics in a seasonal environment. Furthermore, we tested the relevance of habitat connectivity and spatial distribution of stress for the recovery of a local and total population. The simulation results indicated that population recovery is mainly driven by reproductive periods. Furthermore, high habitat connectivity led to faster recovery both for local and total populations. However, effects of landscape structure disappeared for homogeneously stressed populations, where local survivors increased recovery rate. Finally, local populations recovered faster, implying that assessing recovery in the field needs careful consideration of spatial scale for sampling. We emphasize the need for a coherent definition of recovery for more relevant ecosystem risk assessment and management. PMID:22325436

  14. The Mutualistic Side of Wolbachia–Isopod Interactions: Wolbachia Mediated Protection Against Pathogenic Intracellular Bacteria

    PubMed Central

    Braquart-Varnier, Christine; Altinli, Mine; Pigeault, Romain; Chevalier, Frédéric D.; Grève, Pierre; Bouchon, Didier; Sicard, Mathieu

    2015-01-01

    Wolbachia is a vertically transmitted endosymbiont whose radiative success is mainly related to various host reproductive manipulations that led to consider this symbiont as a conflictual reproductive parasite. However, lately, some Wolbachia have been shown to act as beneficial symbionts by protecting hosts against a broad range of parasites. Still, this protection has been mostly demonstrated in artificial Wolbachia-host associations between partners that did not co-evolved together. Here, we tested in two terrestrial isopod species Armadillidium vulgare and Porcellio dilatatus whether resident Wolbachia (native or non-native) could confer protection during infections with Listeria ivanovii and Salmonella typhimurium and also during a transinfection with a Wolbachia strain that kills the recipient host (i.e., wVulC in P. dilatatus). Survival analyses showed that (i) A. vulgare lines hosting their native Wolbachia (wVulC) always exhibited higher survival than asymbiotic ones when infected with pathogenic bacteria (ii) P. dilatatus lines hosting their native wDil Wolbachia strain survived the S. typhimurium infection better, while lines hosting non-native wCon Wolbachia strain survived the L. ivanovii and also the transinfection with wVulC from A. vulgare better. By studying L. ivanovii and S. typhimurium loads in the hemolymph of the different host-Wolbachia systems, we showed that (i) the difference in survival between lines after L. ivanovii infections were not linked to the difference between their pathogenic bacterial loads, and (ii) the difference in survival after S. typhimurium infections corresponds to lower loads of pathogenic bacteria. Overall, our results demonstrate a beneficial effect of Wolbachia on survival of terrestrial isopods when infected with pathogenic intracellular bacteria. This protective effect may rely on different mechanisms depending on the resident symbiont and the invasive bacteria interacting together within the hosts. PMID:26733946

  15. Fish mucus versus parasitic gnathiid isopods as sources of energy and sunscreens for a cleaner fish

    NASA Astrophysics Data System (ADS)

    Eckes, Maxi; Dove, Sophie; Siebeck, Ulrike E.; Grutter, Alexandra S.

    2015-09-01

    The cleaning behaviour of the bluestreak cleaner wrasse Labroides dimidiatus is extensively used as a model system for understanding cooperation. It feeds mainly on blood-sucking gnathiid isopods and also on the epidermal mucus of client fish; the nutritional quality of these foods, however, is unknown. The epidermal mucus of reef fish contains ultraviolet (UV)-absorbing compounds (mycosporine-like amino acids, MAAs), which are only obtained via the diet; nevertheless, while La. dimidiatus has high amounts of MAAs in its mucus, their source is unknown. Therefore, the energetic value (calories and protein estimated using carbon and nitrogen) and MAA level in gnathiids and mucus from several clients [parrotfishes, wrasses (Labridae), and a snapper (Lutjanidae)] were determined. The energetic value of mucus and gnathiids varied among fishes. Overall, carbon, nitrogen, calories, and protein per dry weight were higher in the mucus of most client species compared to gnathiids. Thus, depending on the client species, mucus may be energetically more advantageous for cleaner wrasse to feed on than gnathiids. UV absorbance, a confirmed proxy for MAA levels, indicated high MAA levels in mucus, whereas gnathiids had no detectable MAAs. This suggests that La. dimidiatus obtain MAAs from mucus but not from gnathiids. Hence, in addition to energy, the mucus of some clients also provides La. dimidiatus with the added bonus of UV-absorbing compounds. This may explain why cleaner fish prefer to feed on mucus over gnathiid isopods. The likely costs and benefits to clients of the removal of UV protecting mucus and parasitic gnathiids, respectively, and the variation in benefits gained by cleaner fish from feeding on these foods may explain some variation in cooperation levels in cleaning interactions.

  16. Calcium translocations during the moulting cycle of the semiterrestrial isopod Ligia hawaiiensis (Oniscidea, Crustacea).

    PubMed

    Ziegler, Andreas; Hagedorn, Monica; Ahearn, Gregory A; Carefoot, Thomas H

    2007-01-01

    Terrestrial isopods moult first the posterior and then the anterior half of the body. During the moulting cycle they retain a significant fraction of cuticular calcium partly by storing it in sternal CaCO(3) deposits. We analysed the calcium content in whole Ligia hawaiiensis and the calcium distribution between the posterior, the anterior ventral, and the anterior dorsal cuticle during four stages of the moulting cycle. The results indicate that: (1) overall, about 80% of the calcium is retained and 20% is lost with the exuviae, (2) in premoult 68% of the calcium in the posterior cuticle is resorbed (23% moved to the anterior ventral cuticle, 17% to the anterior dorsal cuticle, and the remaining 28% to internal tissues), (3) after the posterior moult 83% of the calcium in the anterior cuticle is shifted to the posterior cuticle and possibly to internal storage sites, (4) following the anterior moult up to 54% of the calcium in the posterior cuticle is resorbed and used to mineralise the new anterior cuticle. (45)Ca-uptake experiments suggest that up to 80% of calcium lost with the anterior exuviae may be regained after its ingestion. Whole body calcium of Ligia hawaiiensis is only 0.7 times that of the fully terrestrial isopods. These terrestrial species can retain only 48% of whole body calcium, suggesting that the amount of calcium that can be retained by shifting it between the anterior and posterior integument is limited. We propose that fully terrestrial Oniscidea rely to a larger degree on other calcium sources like internal stores and uptake from the ingested exuviae. PMID:16927108

  17. The Mutualistic Side of Wolbachia-Isopod Interactions: Wolbachia Mediated Protection Against Pathogenic Intracellular Bacteria.

    PubMed

    Braquart-Varnier, Christine; Altinli, Mine; Pigeault, Romain; Chevalier, Frédéric D; Grève, Pierre; Bouchon, Didier; Sicard, Mathieu

    2015-01-01

    Wolbachia is a vertically transmitted endosymbiont whose radiative success is mainly related to various host reproductive manipulations that led to consider this symbiont as a conflictual reproductive parasite. However, lately, some Wolbachia have been shown to act as beneficial symbionts by protecting hosts against a broad range of parasites. Still, this protection has been mostly demonstrated in artificial Wolbachia-host associations between partners that did not co-evolved together. Here, we tested in two terrestrial isopod species Armadillidium vulgare and Porcellio dilatatus whether resident Wolbachia (native or non-native) could confer protection during infections with Listeria ivanovii and Salmonella typhimurium and also during a transinfection with a Wolbachia strain that kills the recipient host (i.e., wVulC in P. dilatatus). Survival analyses showed that (i) A. vulgare lines hosting their native Wolbachia (wVulC) always exhibited higher survival than asymbiotic ones when infected with pathogenic bacteria (ii) P. dilatatus lines hosting their native wDil Wolbachia strain survived the S. typhimurium infection better, while lines hosting non-native wCon Wolbachia strain survived the L. ivanovii and also the transinfection with wVulC from A. vulgare better. By studying L. ivanovii and S. typhimurium loads in the hemolymph of the different host-Wolbachia systems, we showed that (i) the difference in survival between lines after L. ivanovii infections were not linked to the difference between their pathogenic bacterial loads, and (ii) the difference in survival after S. typhimurium infections corresponds to lower loads of pathogenic bacteria. Overall, our results demonstrate a beneficial effect of Wolbachia on survival of terrestrial isopods when infected with pathogenic intracellular bacteria. This protective effect may rely on different mechanisms depending on the resident symbiont and the invasive bacteria interacting together within the hosts. PMID:26733946

  18. An holistic approach to beach erosion vulnerability assessment

    NASA Astrophysics Data System (ADS)

    Alexandrakis, George; Poulos, Serafim Ε.

    2014-08-01

    Erosion is a major threat for coasts worldwide, beaches in particular, which constitute one of the most valuable coastal landforms. Vulnerability assessments related to beach erosion may contribute to planning measures to counteract erosion by identifying, quantifying and ranking vulnerability. Herein, we present a new index, the Beach Vulnerability Index (BVI), which combines simplicity in calculations, easily obtainable data and low processing capacity. This approach provides results not only for different beaches, but also for different sectors of the same beach and enables the identification of the relative significance of the processes involved. It functions through the numerical approximation of indicators that correspond to the mechanisms related to the processes that control beach evolution, such as sediment availability, wave climate, beach morhodynamics and sea level change. The BVI is also intended to be used as a managerial tool for beach sustainability, including resilience to climate change impact on beach erosion.

  19. An holistic approach to beach erosion vulnerability assessment.

    PubMed

    Alexandrakis, George; Poulos, Serafim Ε

    2014-01-01

    Erosion is a major threat for coasts worldwide, beaches in particular, which constitute one of the most valuable coastal landforms. Vulnerability assessments related to beach erosion may contribute to planning measures to counteract erosion by identifying, quantifying and ranking vulnerability. Herein, we present a new index, the Beach Vulnerability Index (BVI), which combines simplicity in calculations, easily obtainable data and low processing capacity. This approach provides results not only for different beaches, but also for different sectors of the same beach and enables the identification of the relative significance of the processes involved. It functions through the numerical approximation of indicators that correspond to the mechanisms related to the processes that control beach evolution, such as sediment availability, wave climate, beach morhodynamics and sea level change. The BVI is also intended to be used as a managerial tool for beach sustainability, including resilience to climate change impact on beach erosion. PMID:25123815

  20. Setting conservation targets for sandy beach ecosystems

    NASA Astrophysics Data System (ADS)

    Harris, Linda; Nel, Ronel; Holness, Stephen; Sink, Kerry; Schoeman, David

    2014-10-01

    Representative and adequate reserve networks are key to conserving biodiversity. This begs the question, how much of which features need to be placed in protected areas? Setting specifically-derived conservation targets for most ecosystems is common practice; however, this has never been done for sandy beaches. The aims of this paper, therefore, are to propose a methodology for setting conservation targets for sandy beach ecosystems; and to pilot the proposed method using data describing biodiversity patterns and processes from microtidal beaches in South Africa. First, a classification scheme of valued features of beaches is constructed, including: biodiversity features; unique features; and important processes. Second, methodologies for setting targets for each feature under different data-availability scenarios are described. From this framework, targets are set for features characteristic of microtidal beaches in South Africa, as follows. 1) Targets for dune vegetation types were adopted from a previous assessment, and ranged 19-100%. 2) Targets for beach morphodynamic types (habitats) were set using species-area relationships (SARs). These SARs were derived from species richness data from 142 sampling events around the South African coast (extrapolated to total theoretical species richness estimates using previously-established species-accumulation curve relationships), plotted against the area of the beach (calculated from Google Earth imagery). The species-accumulation factor (z) was 0.22, suggesting a baseline habitat target of 27% is required to protect 75% of the species. This baseline target was modified by heuristic principles, based on habitat rarity and threat status, with final values ranging 27-40%. 3) Species targets were fixed at 20%, modified using heuristic principles based on endemism, threat status, and whether or not beaches play an important role in the species' life history, with targets ranging 20-100%. 4) Targets for processes and 5) important assemblages were set at 50%, following other studies. 6) Finally, a target for an outstanding feature (the Alexandria dunefield) was set at 80% because of its national, international and ecological importance. The greatest shortfall in the current target-setting process is in the lack of empirical models describing the key beach processes, from which robust ecological thresholds can be derived. As for many other studies, our results illustrate that the conservation target of 10% for coastal and marine systems proposed by the Convention on Biological Diversity is too low to conserve sandy beaches and their biota.

  1. Virginia Beach Public Library System, Virginia Beach/Oceanfront Branch: A Community Analysis.

    ERIC Educational Resources Information Center

    Powell, Carolyn L., Comp.; And Others

    This study provides an overview of the community and the status of the library through an examination of the city of Virginia Beach, including its demography and needs, as well as the history, organization, administration, and financial support of both the Virginia Beach Public Library System and the Oceanfront Branch Library. The information is…

  2. 77 FR 50019 - Safety Zone; Cocoa Beach Air Show, Atlantic Ocean, Cocoa Beach, FL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-20

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Cocoa Beach Air Show, Atlantic Ocean, Cocoa... establishing a temporary safety zone on the waters of the Atlantic Ocean located east of Cocoa Beach, Florida...) 366-9826. SUPPLEMENTARY INFORMATION: Table of Acronyms DHS Department of Homeland Security FR...

  3. Transformation of Palm Beach Community College to Palm Beach State College: A Case Study

    ERIC Educational Resources Information Center

    Basiratmand, Mehran

    2013-01-01

    The purpose of this single-site case study was to examine the organization and leadership change process of Palm Beach State College, a publicly funded institution in Florida, as it embarked on offering bachelor's degree programs. The study examined the organizational change process and the extent to which Palm Beach State College's organization…

  4. Advanced Decision-Support for Coastal Beach Health: Virtual Beach 3.0

    EPA Science Inventory

    Virtual Beach is a free decision-support system designed to help beach managers and researchers construct, evaluate, and operate site-specific statistical models that can predict levels of fecal indicator bacteria (FIB) based on environmental conditions that are more readily mea...

  5. Undertow over a barred beach

    NASA Astrophysics Data System (ADS)

    Faria, A. F. Garcez; Thornton, E. B.; Lippmann, T. C.; Stanton, T. P.

    2000-07-01

    The spatial distribution of the mean cross-shore flow (undertow) over a barred beach is examined with field data obtained on three energetic wave days during the Duck94 experiment. The vertical structure of the undertow is modeled using a turbulent eddy viscosity closure and includes the important effects of wave breaking (described using the roller concept) and convective acceleration of the current. Other than a more realistic description of observed turbulence variations, a depth-dependent eddy viscosity (compared with a constant) does not improve the agreement between predicted and observed undertow profiles. The effect of using different boundary conditions is investigated by extending the formulations of Stive and Wind [1986] and Svendsen et al. [1987] to include random waves by ensemble averaging over the wave height distribution. The contribution of breaking wave rollers to the surface mass flux can be of the same order or greater than the contribution associated with the organized wave motion. The largest discrepancies between model predictions and observations occur over the sandbar, where the mass transport of the breaking waves appears to be underestimated.

  6. Shoreface storm morphodynamics and mega-rip evolution at an embayed beach: Bondi Beach, NSW, Australia

    NASA Astrophysics Data System (ADS)

    McCarroll, R. Jak; Brander, Robert W.; Turner, Ian L.; Leeuwen, Ben Van

    2016-03-01

    Embayed beach dynamics differ from open beaches due to the nature of headland control. Their resultant morphologies and morphodynamic behaviour are poorly understood due in part to a critical lack of surfzone and nearshore bathymetry observations. This study describes the morphodynamic storm response of a high-energy intermediate, 850 m long embayed beach over a three week period spanning a cluster of storms. A headland and subaqueous ridge protects the northern end of the beach, resulting in an alongshore wave height gradient. Contrary to existing beach state conceptual models, under energetic forcing the beach did not 'reset' or enter a 'cellular mega-rip' beach state. The protected northern end persisted in a low energy state, while the wave exposed southern section transitioned from transverse-bar-and-rip to a complex double-bar system, a process previously undescribed in the literature. Bar-rip morphology at the exposed end of the beach migrated offshore to greater depths, leaving an inner-reflective beach and longshore trough, while a mega-rip channel with 3 m relief developed at the exposed headland. The number of rip channels remained near constant over multiple storm events. Offshore sediment flux was 350 m3/m at the exposed headland and 20 m3/m at the protected end. Alongshore bathymetric non-uniformity decreased over the sub-aerial beach and inner surfzone, but increased in the outer surfzone and beyond. Suggested mechanisms for the persistence of 3D morphology during the cluster of storms include: (i) wave refraction to shore normal within the embayment; (ii) alongshore energy gradients; and (iii) pre-existing bar-rip morphology. Formation of the complex multi-bar state may be related to antecedent morphology, headland geometry, substrate gradient and localised hydrodynamic interactions near the headland. A new conceptual embayed beach state model is proposed for asymmetric, transitional embayed beaches. The model describes a pre-storm embayment where beach state changes gradually alongshore, while the post-storm embayment exhibits an extreme alongshore morphological gradient, from low-energy intermediate to a "complex multi-bar and mega-rip" state at the exposed end of the beach. Further observations are required to determine the prevalence of this high-energy state and to provide inputs to future numerical models designed to examine the dominant forcing controls involved in its formation.

  7. Effects of microclimate on behavioural and life history traits of terrestrial isopods: implications for responses to climate change.

    PubMed

    Dixie, Bernice; White, Hollie; Hassall, Mark

    2015-01-01

    The sensitivity of terrestrial isopods to changes in both temperature and moisture make them suitable models for examining possible responses of arthropod macro-decomposers to predicted climate change. Effects of changes in both temperature and relative humidity on aggregation, growth and survivorship of species of isopods contrasting in their morphological and physiological adaptations to moisture stress have been investigated in laboratory microcosms. All three traits were more sensitive to a reduction in relative humidity of 20-25% than they were to an increase in temperature of 5-6 °C. These results suggest that predicted changes in climate in south east England may reduce the extent to which soil animals stimulate microbial activity and hence carbon dioxide (CO2) emissions from soils in the future. This may help to mitigate the potential for a positive feedback between increased CO2 emissions from soils, and increased greenhouse effects causing an increase in soil temperatures. PMID:26261446

  8. Effects of microclimate on behavioural and life history traits of terrestrial isopods: implications for responses to climate change

    PubMed Central

    Dixie, Bernice; White, Hollie; Hassall, Mark

    2015-01-01

    Abstract The sensitivity of terrestrial isopods to changes in both temperature and moisture make them suitable models for examining possible responses of arthropod macro-decomposers to predicted climate change. Effects of changes in both temperature and relative humidity on aggregation, growth and survivorship of species of isopods contrasting in their morphological and physiological adaptations to moisture stress have been investigated in laboratory microcosms. All three traits were more sensitive to a reduction in relative humidity of 20–25% than they were to an increase in temperature of 5–6 °C. These results suggest that predicted changes in climate in south east England may reduce the extent to which soil animals stimulate microbial activity and hence carbon dioxide (CO2) emissions from soils in the future. This may help to mitigate the potential for a positive feedback between increased CO2 emissions from soils, and increased greenhouse effects causing an increase in soil temperatures. PMID:26261446

  9. Do predator cues influence turn alternation behavior in terrestrial isopods Porcellio laevis Latreille and Armadillidium vulgare Latreille?

    PubMed

    Hegarty, Kevin G; Kight, Scott L

    2014-07-01

    Terrestrial isopods (Crustacea: Oniscidea) make more alternating maze turns in response to negative stimuli, a navigational behavior that corrects divergence from a straight line. The present study investigates this behavioral pattern in two species, Porcellio laevis Latreille and Armadillidium vulgare Latreille, in response to short-term vs. long-term exposure to indirect cues from predatory ants. Neither isopod species increased the number of alternating turns in response to short-term indirect exposure to ants, but both species made significantly more alternating turns following continuous indirect exposure to ants for a period of one-week. These results are surprising given differences in behavioral and morphological predator defenses between these species (the Armadillidiidae curl into defensive postures when attacked, whereas the Porcellionidae flee). The marked similarity in alternating turn behavior of the two families suggests evolutionary conservation of antipredator navigation mechanisms. PMID:24954552

  10. Isolation and amino acid sequence of a peptide with vitellogenesis inhibiting activity from the terrestrial isopod Armadillidium vulgare (Crustacea).

    PubMed

    Grève, P; Sorokine, O; Berges, T; Lacombe, C; Van Dorsselaer, A; Martin, G

    1999-09-01

    The complete amino acid sequence of a neuropeptide was established using gas-phase microsequencing, mass spectrometry, and reverse transcription-polymerase chain reaction. This peptide, stored in the sinus gland of the terrestrial isopod Armadillidium vulgare, inhibited vitellogenin synthesis by the fat tissue and inhibited the onset of secondary vitellogenesis when tested in homologous bioassays. This peptide, named Arv-VIH, has 83 amino acid residues and a molecular mass of 9485 Da. Relationships with other related peptides are presented. PMID:10480992

  11. The agnarid terrestrial isopods (Isopoda, Oniscidea, Agnaridae) of the province of Qazvin, Iran, with a description of a new species.

    PubMed

    Eshaghi, Behjat; Kiabi, Bahram H; Kashani, Ghasem M

    2015-01-01

    Six species of terrestrial isopods from the province of Qazvin, central Iran, are recorded. Three species, Hemilepistusklugii (Brandt, 1833), Protracheoniscusehsani Kashani, 2014 and Mongoloniscuspersicus Kashani, 2014, were previously reported from the province. Hemilepistuselongatus Budde-Lund, 1885 and Protracheoniscusmajor (Dollfus, 1903) are recorded for the first time, and one species, Protracheoniscussarii sp. n., is described as new. The diagnostic characters of the new species are figured. PMID:26261440

  12. Parasitism of the isopod Artystone trysibia in the fish Chaetostoma dermorhynchum from the Tena River (Amazonian region, Ecuador).

    PubMed

    Junoy, Juan

    2016-01-01

    The isopod Artystone trysibia Schioedte, 1866 is described by using a collection of specimens that were found parasitizing loricariid fish Chaetostoma dermorhynchum Boulenger, 1887 in the Tena River (Napo province, Ecuador, Amazonian region). Additionally to freshly collected specimens, complementary data of the parasite was obtained from preserved fishes at Ecuadorian museums. This is the first record of A. trysibia in Ecuador, and the most upstream location for the species. The new host fish, Chaetostoma dermorhynchum, is used locally as food. PMID:26466983

  13. Description of two new species and redescription of one species of agnarid terrestrial isopods (Oniscidea, Agnaridae) from western Iran.

    PubMed

    Kashani, Ghasem M

    2014-01-01

    The present study reports on three species of terrestrial isopods from western Iran. The genus Mongoloniscus Verhoeff, 1930 is recorded for the first time from Iran, with description of a new species: M. persicus sp. n. Protracheoniscus ehsani sp. n. is described and P. darevskii Borutzky, 1975 is redescribed based on Iranian specimens. The diagnostic characters of these species are figured and their geographical distribution is presented on a map. PMID:25317061

  14. Isopod Inquiry.

    ERIC Educational Resources Information Center

    Mikulka, Thomas

    2000-01-01

    Describes an inquiry-based science activity in which students investigate the preferred food sources of sowbugs. Students design their own experiment, perform a first trial, and refine their procedure before conducting a second trial with more accurate results. (SAH)

  15. Demography of some non-native isopods (Crustacea, Isopoda, Oniscidea) in a Mid-Atlantic forest, USA

    PubMed Central

    Hornung, Elisabeth; Szlavecz, Katalin; Dombos, Miklós

    2015-01-01

    Abstract Introduced species dominate the terrestrial isopod fauna in most inland habitats of North America, including urban landscapes. These non-native species are often very abundant and thus potentially play a significant role in detritus processing. We monitored isopod assemblages in an urban forest for a year to examine the relationship between surface activity and abiotic environmental factors, and to analyze reproductive characteristics that might contribute to their successful establishment. Using pitfall trap samples we recorded five species, two of which, Trachelipus rathkii and Cylisticus convexus, were highly abundant. We determined size, sex and reproductive state of each individual. Surface activity of both species reflected variability in abiotic stress factors for isopods, such as soil moisture and soil temperature. Early spring the main trigger was soil temperature while later in the season increasing temperature and decreasing soil moisture jointly affected population dynamics. Activity significantly correlated with soil moisture. The temporal pattern of sex ratios supported the secondary sex ratio hypothesis. Males dominated the samples on the onset of the mating season in search of females. The pattern was reversed as females searched for suitable microsites for their offspring. Size independent fecundity decreased as conditions became more stressful late in the season. PMID:26261445

  16. Multiple Conserved Heteroplasmic Sites in tRNA Genes in the Mitochondrial Genomes of Terrestrial Isopods (Oniscidea).

    PubMed

    Chandler, Christopher H; Badawi, Myriam; Moumen, Bouziane; Grève, Pierre; Cordaux, Richard

    2015-07-01

    Mitochondrial genome structure and organization are relatively conserved among metazoans. However, in many isopods, especially the terrestrial isopods (Oniscidea), the mitochondrial genome consists of both ?14-kb linear monomers and ?28-kb circular dimers. This unusual organization is associated with an ancient and conserved constitutive heteroplasmic site. This heteroplasmy affects the anticodon of a tRNA gene, allowing this single locus to function as a "dual" tRNA gene for two different amino acids. Here, we further explore the evolution of these unusual mitochondrial genomes by assembling complete mitochondrial sequences for two additional Oniscidean species, Trachelipus rathkei and Cylisticus convexus. Strikingly, we find evidence of two additional heteroplasmic sites that also alter tRNA anticodons, creating additional dual tRNA genes, and that are conserved across both species. These results suggest that the unique linear/circular organization of isopods' mitochondrial genomes may facilitate the evolution of stable mitochondrial heteroplasmies, and, conversely, once such heteroplasmies have evolved, they constrain the multimeric structure of the mitochondrial genome in these species. Finally, we outline some possible future research directions to identify the factors influencing mitochondrial genome evolution in this group. PMID:25911226

  17. Demography of some non-native isopods (Crustacea, Isopoda, Oniscidea) in a Mid-Atlantic forest, USA.

    PubMed

    Hornung, Elisabeth; Szlavecz, Katalin; Dombos, Miklós

    2015-01-01

    Introduced species dominate the terrestrial isopod fauna in most inland habitats of North America, including urban landscapes. These non-native species are often very abundant and thus potentially play a significant role in detritus processing. We monitored isopod assemblages in an urban forest for a year to examine the relationship between surface activity and abiotic environmental factors, and to analyze reproductive characteristics that might contribute to their successful establishment. Using pitfall trap samples we recorded five species, two of which, Trachelipusrathkii and Cylisticusconvexus, were highly abundant. We determined size, sex and reproductive state of each individual. Surface activity of both species reflected variability in abiotic stress factors for isopods, such as soil moisture and soil temperature. Early spring the main trigger was soil temperature while later in the season increasing temperature and decreasing soil moisture jointly affected population dynamics. Activity significantly correlated with soil moisture. The temporal pattern of sex ratios supported the secondary sex ratio hypothesis. Males dominated the samples on the onset of the mating season in search of females. The pattern was reversed as females searched for suitable microsites for their offspring. Size independent fecundity decreased as conditions became more stressful late in the season. PMID:26261445

  18. Morphological and physiological development of anterior thoracic stretch receptors in two isopods, Armadillidium vulgare and Ligia exotica.

    PubMed

    Iwasaki, Masazumi; Ohata, Ayako; Niida, Akiyoshi

    2007-07-01

    Abdominal muscle receptor organs (MROs) monitor the position and movement of abdomen in crustaceans. Thoracic segments of decapods are fused and immovable. It is speculated that MROs had retrograded simple shape, N-cells that lost receptor muscles, a receptor cell and accessory nerves. We focused on the effect of segmental movement in respect to thoracic N-cells and MROs in isopods that have movable thoracic segments. Armadillidium vulgare rolled up its body segments. Ligia exotica swam by quick movement of the posterior thoracic segments. Both isopods possessed N-cells and MROs in the thorax. N-cells were a simple structure, but N-cells from the second and third thoracic segments of A. vulgare had a muscle strand. MROs(T3-T4) (from the third and fourth thoracic segments) of A. vulgare had two receptor muscles. MROs(T3-T4) of L. exotica had one long receptor muscle. N-cells of both species and MROs of A. vulgare showed slowly adapting stretch-activated discharges. MROs of L. exotica showed both slowly and rapidly adapting discharges. The stretch-activated responses of N-cells and MROs inhibited each other. N-cells or MROs in the thorax of isopods are not related to the segmental structure. The morphology and physiology of N-cells and MROs are specialized to species-specific behaviors. PMID:17473927

  19. Subacute effects of transgenic crylab bacillus thuringiensis corn litter on the isopods Trachelipus rathkii and armadillidium nasatum.

    PubMed

    Clark, Bryan W; Prihoda, Kelsey R; Coats, Joel R

    2006-10-01

    Laboratory studies were conducted to investigate the subacute effects of transgenic Cry1Ab corn leaf material containing Bacillus thuringiensis (Bt) protein on the terrestrial isopods Trachelipus rathkii and Armadillidium nasatum. Survival and growth were measured for eight weeks in isopods fed leaf material of two Bt11 corn varieties, two Monsanto 810 (Mon810) corn varieties, and the isolines of each. Total lipid and protein content of the organisms was measured to examine effects on energetic reserves. Armadillidium nasatum individuals in all treatments responded similarly. For T. rathkii, no statistically significant effect of Bt was observed, but statistical differences were observed in growth between hybrids. Protein and sugar content of the food were found to be correlated with the differences in growth for T. rathkii. Total protein content was higher in T. rathkii and A. nasatum fed material with higher protein and sugar content. A trend toward less growth in T. rathkii on Bt corn varieties versus their isolines triggered a concentration-response assay with purified Cry1Ab protein. No adverse effects of purified Bt protein were observed. These results indicate that little hazard to T. rathkii and A. nasatum from Bt corn leaf material from these hybrids exists. However, nutritional differences in corn hybrids contributed to differences in isopod growth. PMID:17022406

  20. Locomotory activity and feeding strategy of the hadal munnopsid isopod Rectisura cf. herculea (Crustacea: Asellota) in the Japan Trench.

    PubMed

    Jamieson, Alan J; Fujii, Toyonobu; Priede, Imants G

    2012-09-01

    Benthic fauna in the hadal zone (6500-11,000 m) rely on maintaining sufficient locomotory activity to exploit a low, patchy and uniquely distributed food supply while exposed to high pressure, low temperatures and responding to predator-prey interactions. Very little is currently known about the locomotory capabilities of hadal fauna. In situ video footage of the isopod Rectisura cf. herculea (Birstein 1957) (Asellota, Munnopsidae) was obtained from 6945 and 7703 m deep in the Japan Trench (NW Pacific Ocean). Measurements of locomotion revealed routine walking speeds of 0.19 ± 0.04 BL s(-1) (mean ± s.d.), increasing to 0.33 ± 0.04 BL s(-1) if naturally perturbed by larger organisms. When immediately threatened by the presence of predators (decapod crustaceans), the isopods are capable of eliciting backward escape jumps and burst swimming escape responses of 2.6 ± 1.5 BL s(-1) and 4.63 ± 0.9 BL s(-1), respectively. These data suggest no significant reduction in locomotory capability despite the extreme depths in which they inhabit. These observations also revealed the isopod to be a bait-attending and aggregative species and suggest that it may not be obligatorily selecting infaunal food sources as previously thought. PMID:22875769

  1. Predator faunas past and present: quantifying the influence of waterborne cues in divergent ecotypes of the isopod Asellus aquaticus.

    PubMed

    Harris, Sanna; Karlsson Green, Kristina; Pettersson, Lars B

    2013-11-01

    Waterborne chemical cues are an important source of information for many aquatic organisms, in particular when assessing the current risk of predation. The ability to use chemical cues to detect and respond to potential predators before an actual encounter can improve prey chances of survival. We investigated predator recognition and the impact of chemical cues on predator avoidance in the freshwater isopod Asellus aquaticus. This isopod has recently colonised a novel habitat and diverged into two distinct ecotypes, which encounter different predator communities. Using laboratory-based choice experiments, we have quantified behavioural responses to chemical cues from predators typical of the two predator communities (larval dragonflies in the ancestral habitat, perch in the newly colonised habitat) in wild-caught and lab-reared Asellus of the two ecotypes. Individuals with prior experience of predators showed strong predator avoidance to cues from both predator types. Both ecotypes showed similar antipredator responses, but sexes differed in terms of threat-sensitive responses with males avoiding areas containing predator cues to a larger extent than females. Overall, chemical cues from fish elicited stronger predator avoidance than cues from larval dragonflies. Our results indicate that in these isopods, prior exposure to predators is needed to develop antipredator behaviour based on waterborne cues. Furthermore, the results emphasise the need to analyse predator avoidance in relation to waterborne cues in a sex-specific context, because of potential differences between males and females in terms of vulnerability and life history strategies. PMID:23636460

  2. Threats to sandy beach ecosystems: A review

    NASA Astrophysics Data System (ADS)

    Defeo, Omar; McLachlan, Anton; Schoeman, David S.; Schlacher, Thomas A.; Dugan, Jenifer; Jones, Alan; Lastra, Mariano; Scapini, Felicita

    2009-01-01

    We provide a brief synopsis of the unique physical and ecological attributes of sandy beach ecosystems and review the main anthropogenic pressures acting on the world's single largest type of open shoreline. Threats to beaches arise from a range of stressors which span a spectrum of impact scales from localised effects (e.g. trampling) to a truly global reach (e.g. sea-level rise). These pressures act at multiple temporal and spatial scales, translating into ecological impacts that are manifested across several dimensions in time and space so that today almost every beach on every coastline is threatened by human activities. Press disturbances (whatever the impact source involved) are becoming increasingly common, operating on time scales of years to decades. However, long-term data sets that describe either the natural dynamics of beach systems or the human impacts on beaches are scarce and fragmentary. A top priority is to implement long-term field experiments and monitoring programmes that quantify the dynamics of key ecological attributes on sandy beaches. Because of the inertia associated with global climate change and human population growth, no realistic management scenario will alleviate these threats in the short term. The immediate priority is to avoid further development of coastal areas likely to be directly impacted by retreating shorelines. There is also scope for improvement in experimental design to better distinguish natural variability from anthropogenic impacts. Sea-level rise and other effects of global warming are expected to intensify other anthropogenic pressures, and could cause unprecedented ecological impacts. The definition of the relevant scales of analysis, which will vary according to the magnitude of the impact and the organisational level under analysis, and the recognition of a physical-biological coupling at different scales, should be included in approaches to quantify impacts. Zoning strategies and marine reserves, which have not been widely implemented in sandy beaches, could be a key tool for biodiversity conservation and should also facilitate spillover effects into adjacent beach habitats. Setback and zoning strategies need to be enforced through legislation, and all relevant stakeholders should be included in the design, implementation and institutionalisation of these initiatives. New perspectives for rational management of sandy beaches require paradigm shifts, by including not only basic ecosystem principles, but also incentives for effective governance and sharing of management roles between government and local stakeholders.

  3. Ontogeny of behavioural adaptations in beach crustaceans: some temporal considerations for integrated coastal zone management and conservation

    NASA Astrophysics Data System (ADS)

    Naylor, E.; Kennedy, F.

    2003-10-01

    So-called "typical" behavioural responses of coastal animals to particular stimuli have previously been shown often to vary cyclically in phase with diel or tidal cycles in the environment. Less well-studied are differences in the behaviour of adults and juveniles of the same species at the same time of day or tidal state, or in response to the same stimulus. Experimental studies of such differences in behaviour are reviewed and compared for three species of beach crustaceans, namely, the crab Carcinus maenas, the isopod Eurydice pulchra and the amphipod Orchestoidea tuberculata. Juvenile, but not adult, Carcinus will entrain circatidal rhythmicity after exposure to artificial tidal cycles of immersion/emersion; juvenile, but not adult, Eurydice express pronounced free-running circatidal swimming rhythms at neap tides as well as at springs; and, in Orchestoidea, juveniles and adults express patterns of daily locomotor activity that are complementary, both on the shore and in the laboratory. These ontogenetic differences are discussed in relation to distributional and behavioural differences between adults and juveniles in each species, drawing attention to their adaptive significance and wider implications for coastal management and conservation.

  4. USING PUBLIC-DOMAIN MODELS TO ESTIMATE BEACH BACTERIA CONCENTRATIONS

    EPA Science Inventory

    Stretches of beach along popular Huntington Beach, California are occassionally closed to swimming due to high levels of bacteria. One hypothesized source is the treated wastewater plume from the Orange County Sanitation District's (OCSD) ocean outfall. While three independent sc...

  5. Climatic Signals in Beach Volume Measurements from 19 Intermediate Embayed Beaches

    NASA Astrophysics Data System (ADS)

    Bryan, K. R.; Coco, G.; Blossier, B.; Smith, R. K.; Wood, A.

    2014-12-01

    The northeast coast of New Zealand has a range of embayed intermediate beaches whose cross-shore profiles can vary on time scales extending from individual storms to inter-decadal. Some of these beaches erode and accrete a lot whereas others can remain extraordinarily stable despite exposure to comparable wave climates. Here a profile dataset collected intermittently since 1980, and 6-weekly since 1995, on 19 northeast coast beaches (62 profiles) is used to study variability between sites. Spectral analysis of the profile data showed annual, biannual and interannual energy, with the relative magnitude varying surprisingly between sites. Wave climate information for the sites was provided by a regional SWAN model which had been forced by data extracted from the NOAA WWIII wave database. Waves were modelled from 1980-2008. The wave climate was used to cluster the beaches into those that were likely to behave in a similar way, based on the relative proportions of variability in these time scales in the significant wave height, mean period and alongshore wave energy flux extracted from model output. Beaches with a northward aspect had generally low biannual variability but higher interannual and seasonal variability. In contrast, sites exposed to easterly conditions had a greater biannual contribution. Analysis of climate indicators show that the southern oscillation index and the Pacific decadal oscillation also have variability in seasonal, biannual and interannual scales to different degrees and these are weakly but significantly correlated to beach volume variations. Overall, the degree of correlation appears directly related to beach orientation.

  6. A multi-beach study of Staphylococcus aureus, MRSA, and enterococci in seawater and beach sand.

    PubMed

    Goodwin, Kelly D; McNay, Melody; Cao, Yiping; Ebentier, Darcy; Madison, Melissa; Griffith, John F

    2012-09-01

    Incidences of Staphylococcus aureus and methicillin resistant S. aureus (MRSA) have risen worldwide prompting a need to better understand routes of human exposure and whether standard bacterial water quality monitoring practices adequately account for this potential threat. Beach water and sand samples were analyzed during summer months for S. aureus, enterococci, and MRSA at three southern California beaches (Avalon, Doheny, Malibu Surfrider). S. aureus frequently was detected in samples of seawater (59%, n = 328) and beach sand (53%, n = 358). MRSA sometimes was detected in seawater (1.6%, n = 366) and sand (2.7%, n = 366) at relatively low concentrations. Site specific differences were observed, with Avalon Beach presenting the highest concentrations of S. aureus and Malibu Surfrider the lowest in both seawater and sand. S. aureus concentrations in seawater and sand were correlated to each other and to a variety of other parameters. Multiple linear regression on the combined beach data indicated that significant explanatory variables for S. aureus in seawater were S. aureus in sand, water temperature, enterococci in seawater, and the number of swimmers. In sand, S. aureus concentrations were related to S. aureus in seawater, water temperature, enterococci in seawater, and inversely to surf height classification. Only the correlation to water temperature held for individually analyzed beaches and for S. aureus concentrations in both seawater and sand. To provide context for these results, the prevalence of S. aureus in sand was compared to published fomite studies, and results suggested that beach prevalence was similar to that in homes. PMID:22652414

  7. Depositional settings of sand beaches along whitewater rivers

    USGS Publications Warehouse

    Vincent, K.R.; Andrews, E.D.

    2008-01-01

    The numbers and sizes of sand beaches suitable for recreation along selected whitewater rivers in the western United States depend on sand concentrations, range of discharge and the size, frequency and type of depositional settings. River-width expansions downstream from constrictions are the predominant depositional setting for sand beaches in the upper Grand Canyon and along five Wild and Scenic Rivers in Idaho, but not along other rivers. Beaches located upstream from constrictions are rare, in general, except in the Grand Canyon. Beaches found in expansions without constrictions dominate depositional sites along the Yampa and Green Rivers, are fairly common along the rivers in Idaho, but are relatively rare in the Grand Canyon. The magnitude of flow expansion is a reliable predictor of beach size. Beaches located on the inside of curves are uncommon, in general, but can be important recreation sites. The mid-channel bar setting is the least important from a recreation standpoint because that setting is rare and beaches there are typically small, and emergent only at low flow. The frequency of beaches is highly variable among rivers and the concentration of sand in transport is only partially responsible. Of the rivers studied, the unregulated Yampa River carries the highest concentrations of suspended sand and has among the most beaches (1.2 beaches km-1). Emergent sand beaches are essentially nonexistent along the Deschutes River and are rare along other Oregon rivers, yet these rivers transport some sand. Sand beaches are fairly common (0.8-1.1 beaches km-1) along the regulated Colorado River, but are comparatively rare (0.6 beaches km-1) along the unregulated Middle Fork Salmon River. The suspended sand concentrations in study reaches of these two rivers are similar, and the difference in the frequency of beaches may be largely because the processes that create beach-deposition settings are less active along the Middle Fork Salmon.

  8. An evaluation of beached bird monitoring approaches.

    PubMed

    Seys, Jan; Offringa, Henk; Van Waeyenberge, Jeroen; Meire, Patrick; Kuijken, Eckhart

    2002-04-01

    Oil-pollution monitoring at sea through beach bird surveying would undoubtedly benefit from a further standardisation of methods, enhancing the efficiency of data collection. In order to come up with useful recommendations, we evaluated various approaches of beached bird collection at the Belgian coast during seven winters (1993-1999). Data received in a passive way by one major rehabilitation centre were compared to the results of targeted beach surveys carried out at different scales by trained ornithologists: 'weekly' surveys - with a mean interval of 9 days - restricted to a fixed 16.7 km beach stretch, 'monthly' surveys over the entire coastline (62.1 km) and an annual 'international' survey in Belgium over the same distance at the end of February. Data collected through Belgian rehabilitation centres concern injured, living birds collected in a non-systematical way. Oil rates derived from these centres appear to be strongly biased to oiled auks and inshore bird species, and are hence of little use in assessing the extent of oil pollution at sea. The major asset of rehabilitation centres in terms of data collection seems to be their continuous warning function for events of mass mortality. Weekly surveys on a representative and large enough section rendered reliable data on oil rates, estimates of total number of bird victims, representation of various taxonomic groups and species-richness and were most sensitive in detecting events quickly (wrecks, oil-slicks, severe winter mortality, etc.). Monthly surveys gave comparable results, although they overlooked some important beaching events and demonstrated slightly higher oil rates, probably due to the higher chance to miss short-lasting wrecks of auks. Since the monthly surveys in Belgium were carried out by a network of volunteers and were spread over a larger beach section, they should be considered as best performing. Single 'international beached bird surveys' in February gave reliable data on total victim number (once the mean ratio between numbers in various months is known) and oil rate (provided a sufficiently large sample can be collected), but failed in tracking events. It is a particularly attractive approach because of its long tradition, resulting in invaluable long-term databases, and the uniformity in which these surveys are organised on a large scale. The minimal distance for a monthly survey amounts to 25-30 km (40-50% of Belgian coastline) up to 40 km (65%) in order to attain sound figures for oil rate and species-richness, respectively. These distances are primarily determined by the number of bird corpses that may be collected and are hence a function of beaching intensity and corpse detection rate. PMID:12139322

  9. Feeding behaviour of the terrestrial isopod Porcellionides pruinosus Brandt, 1833 (Crustacea, Isopoda) in response to changes in food quality and contamination.

    PubMed

    Loureiro, Susana; Sampaio, Alexandra; Brandão, Ana; Nogueira, António J A; Soares, Amadeu M V M

    2006-10-01

    Soil decomposition is mainly dependent on the nature and characteristics of organic matter within the soil, the environmental conditions and the activity of microorganisms and soil fauna. Isopods play an important role in decomposition through litter fragmentation and stimulating and/or ingesting fungi and bacteria. The aim of this study was to jointly evaluate the effect of different food types and the effect of heavy metal contamination of those foods through isopod feeding performance assays. These studies used the terrestrial isopod Porcellionides pruinosus. After feeding with different leaf types for the study on feeding performance, alder leaves were chosen for the contamination experiments. Feeding parameters like consumption, assimilation, egestion and growth ratios were calculated and compared among treatments and food type. Lower quality food decreased isopods performance. Exotic food types were shown to be less preferred than alder or oak leaves. Contaminated food also resulted in a decrease in performance among the feeding parameters studies, although isopods can tolerate in certain cases high amounts of heavy metals. For this reason it is possible that in future this crustacean can be used as bioindicators of soil contamination or in the evaluation of contaminated sites or remediation processes. PMID:16842839

  10. Tracer Studies In A Laboratory Beach Subjected To Waves

    EPA Science Inventory

    This work investigated the washout of dissolved nutrients from beaches due to waves by conducting tracer studies in a laboratory beach facility. The effects of waves were studied in the case where the beach was subjected to the tide, and that in which no tidal action was present...

  11. POLYMERASE CHAIN REACTION (PCR) TECHNOLOGY IN VISUAL BEACH

    EPA Science Inventory

    In 2000, the US Congress passed the Beaches Environmental Assessment and Coastal Health Act under which the EPA has the mandate to manage all significant public beaches by 2008. As a result, EPA, USGS and NOAA are developing the Visual Beach program which consists of software eq...

  12. 103. VIEW OF BEACH STRUCTURES ON NORTHWEST SIDE OF PIER, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    103. VIEW OF BEACH STRUCTURES ON NORTHWEST SIDE OF PIER, LOOKING SOUTHEAST; PACIFIC ELECTRIC RAILWAY CAR (UPPER LEFT), CONCESSION STANDS (LOWER LEFT), BANDSHELL (RIGHT), AND PIER IN BACKGROUND Photograph #5352-HB. Photographer unknown, c. 1914 - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  13. Beaches in Motion. Interaction and Environmental Change. Secondary.

    ERIC Educational Resources Information Center

    Lee County School District, Ft. Myers, FL. Dept. of Environmental Education and Instructional Development Services.

    The terms "high energy" and "low energy" refer to the amount of energy a wave has that reaches the face of a beach. In this student guide, two types of beaches are investigated. The objective is to be able to identify whether a beach is of high or low energy. Background information is provided, as well as instructions and worksheets for activities…

  14. 107. VIEW OF BEACH DEVELOPMENT ON NORTHWEST SIDE OF PIER, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    107. VIEW OF BEACH DEVELOPMENT ON NORTHWEST SIDE OF PIER, LOOKING SOUTH-SOUTHEAST. SECTION OF PIER IS IN BACKGROUND Photograph #1579-HB. Photographer unknown, c. 1930-31 prior to replacement of original light standards in 1930-31 - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  15. Monitoring of beach enteromorpha variation with near shore video

    NASA Astrophysics Data System (ADS)

    Hu, Yali; Yu, Xinsheng; Yan, Zhijin; Yi, Weidong

    2014-07-01

    Beach is an important coastal protective barrier and tourism resources. Beach environment monitoring can help beach managers to make feasible decisions. Digital image of video monitoring technology can provide high resolution information of temporal and spatial variation of near shore in real time. The application of Video monitoring technology has been implemented in Qingdao's Shilaoren beach. The clustering method based on Gaussian mixture model is applied to extract beach enteromorpha changs for the digital images. Analysis results show that, the period of enteromorpha in Qingdao's Shilaoren beach was mainly from the early July to the mid-August in 2011, and the decline of enteromorpha is mainly associated with the rising temperature in the mid-August. Storm has significant impact on the beach enteromorpha. Tourists' activity space on the beach will decrease due to the enteromorpha covering on the beach, which affects beach tourism activities. Therefore, it's necessary to make preventive measures to avoid enteromorpha piling up on the beach, which is of great importance to the bathing beach environment and tourism development.

  16. Beach Sand Analysis for Indicators of Microbial Contamination

    EPA Science Inventory

    Traditional beach monitoring has focused on water quality, with little attention paid to health risks associated with beach sand. Recent research has reported that fecal indicator bacteria, as well as human pathogens can be found in beach sand and may constitute a risk to human h...

  17. Genetic and environmental variation in performance of a marine isopod: effects of eutrophication.

    PubMed

    Hemmi, Anne; Jormalainen, Veijo

    2004-07-01

    Environmental variation in food resources modifies performance of herbivores, in addition to genetic variation and maternal effects. In marine benthic habitats, eutrophication may modify herbivores' diets by changing host species composition or nutritional quality of algae for herbivores. We studied experimentally the effects of diet breadth and nutrient availability for the host algae on fitness components of the herbivorous isopod Idotea baltica. We fed the adult isopods with the brown algae Fucus vesiculosus and Pilayella littoralis and juveniles with the green alga Cladophora glomerata. By using half-sib families, we were able to separate the genetic, environmental and maternal effects on intermolt duration and size of the juveniles. The mothers confined to the diet consisting of both Fucus and Pilayella grew better and produced larger egg mass than those having consumed Fucus alone. Nutrient enhancement of algae did not influence the performance of the adult herbivores. However, the juveniles achieved twice the weight as well as shorter intermolt duration when consuming nutrient-treated C. glomerata. Mother's nutrition, either nutrient enrichment of her food algae or diet breadth, did not affect juvenile survival or growth as such, but we found evidence that the broader diet consumed by the mother mediated offspring performance by further accelerating growth rate of the offspring that fed on nutrient-treated alga. Intermolt duration was a highly heritable trait, but size showed very low heritability. Instead, maternal effects on size were substantial, suggesting that differences among mothers in their egg-provisioning ability strongly affect weight gain of their offspring. A high amount of additive genetic variance in intermolt duration implies potential for quick evolutionary responses in the growth schedule in the face of changes in the selective environment. We conclude that eutrophication, in addition to improving growth and reproduction of I. baltica by enhancing food quality and by providing opportunity for broader, more profitable diets, may act as a selective agent on life-history traits. Eutrophication of coastal waters is thus likely to reflect in herbivore density, population dynamics and eventually, grazing pressure of littoral macroalgae. PMID:15146322

  18. North beach (Nazaré) sand tracer experiment

    NASA Astrophysics Data System (ADS)

    Duarte, João; Taborda, Rui; Ribeiro, Mónica; Cascalho, João; Silva, Ana; Bosnic, Ivana

    2014-05-01

    The littoral in the vicinity of Nazaré (West Portuguese coast) is characterized by two distinct coastal stretches separated by Nazaré headland: a northern sector (Norte beach) characterized by a high energetic continuous sandy beach and a southern sector (Nazaré bay beach) that corresponds to an embayed beach, sheltered by the Nazaré headland. The bay is a geomorphological expression of the Nazaré canyon head, which acts as powerful sediment sink, capturing the large longshore net southward transport at Norte beach generated by the north Atlantic high energetic swell. The northern side of the canyon head is carved on highly resistant Cretaceous limestone sustaining an underwater vertical relief that emerges on the Nazaré headland, creating a unusual nearshore wave pattern. This wave pattern not only concentrates high energy levels at the Norte beach but also contributes to local complex longshore drift gradients capable of inducing beach seasonal cross-shore variations of more than 200 m. The main factors that influence local sediment budget are: (1) canyon head capturing and (2) headland sediment bypassing. To obtain a direct measure of the net longshore drift at Norte beach (upstream boundary of the system) a large scale fluorescent tracer experiment was performed. The data will be used to validate longshore transport formulas in a high energetic environment and to access Nazaré canyon head sediment loss. Considering the anticipation of high transport rates, approximately 10 tonnes of native sand where coated with orange fluorescent ink using a set of concrete mixers. The experiment took place on the 9th to 15th September 2013 period and followed the continuous injection method (CIM). The CIM approach was justified by the expected high energy levels that inhibits sediment sampling across the surf zone. During the tracer injection procedure (approx. 5 hours), sediment sampling was performed at 13 sites along a rectilinear coastal stretch extended through 600 m downdrift of the injection point. Tracer was injected at a rate of 16 kg each 30 sec and collected at a frequency of 10 min at each site. Complementary sampling was performed at the inner shelf and at the beach southern of the headland. In order to follow tracer downdrift movement and headland sediment bypassing low resolution sampling was extended through three more days. Oceanographic forcing throughout the experiment was measured by an offshore wave buoy and an ADCP specifically deployed for the experiment. During the first tidal cycle, data from field observations using a hand held UV light showed a southward tracer displacement of more than 600 m. After the second tidal cycle, sediment tracer was detected in the Nazaré bay beach showing headland bypassing. Further insights on the sediment transport at the Nazaré canyon head system will be supported by the analysis of sediment samples collected at the beach and inner shelf using an automated image analysis system. This work was done in the framework of the PTDC/MAR/114674/2009 program, financed by FCT which the authors acknowledge gratefully.

  19. Cosmology at the Beach Lecture: Wayne Hu

    ScienceCinema

    Wayne Hu

    2010-01-08

    Wayne Hu lectures on Secondary Anisotropy in the CMB. The lecture is the first in a series of 3 he delivered as part of the "Cosmology at the Beach" winter school organized by Berkeley Lab's George Smoot in Los Cabos, Mexico from Jan. 12-16, 2009.

  20. USGS Collects Sediments Samples at Pascagoula Beach

    USGS Multimedia Gallery

    U.S. Geological Survey (USGS) scientists collected environmental data and samples at beach, barrier island, and wetland sites in response to the 2010 Deepwater Horizon oil spill in the Gulf of Mexico.  The USGS Florida, Alabama, Mississippi, Louisiana, and Texas Science Centers collaborated to ...

  1. USGS Collects Sediments Samples at Pascagoula Beach

    USGS Multimedia Gallery

    U.S. Geological Survey (USGS) scientists collected environmental data and samples at beach, barrier island, and wetland sites in response to the 2010 Deepwater Horizon oil spill in the Gulf of Mexico.  The USGS Florida, Alabama, Mississippi, Louisiana, and Texas Science Centers collaborated to ...

  2. Walruses Spill Over Beach Banks onto Tundra

    USGS Multimedia Gallery

    Thousands of walruses gathered to rest on the shore near the Alaskan coastal community of Point Lay during September of 2013 after sea ice disappeared from their offshore foraging grounds in the eastern Chukchi Sea. Walruses clamber up on to the grassy tundra of the barrier island, once the beach b...

  3. Beach Erosion and Sea Turtle Nest

    USGS Multimedia Gallery

    This image depicts a cliff-like escarpment in the sand of a Florida beach. Notice the marked turtle nest (background) and the unusual single exposed egg (right foreground). The protective stakes mark a nest from an earlier week as part of a county research program that marks and records every eighth...

  4. Cosmology at the Beach Lecture: Wayne Hu

    SciTech Connect

    Wayne Hu

    2009-03-02

    Wayne Hu lectures on Secondary Anisotropy in the CMB. The lecture is the first in a series of 3 he delivered as part of the "Cosmology at the Beach" winter school organized by Berkeley Lab's George Smoot in Los Cabos, Mexico from Jan. 12-16, 2009.

  5. Beaches, Dunes, and Barrier Islands. Habitat Pac.

    ERIC Educational Resources Information Center

    Fish and Wildlife Service (Dept. of Interior), Washington, DC.

    The materials in this educational packet are designed for use with students in grades 4 through 7. They consist of a leader overview, teaching guides and student data sheets for three activities, and a poster. The leader overview describes the nature of beaches, dunes, and barrier islands, tracing their development, settlement, and management and…

  6. An Interview with Beatrice Beach Szekely

    ERIC Educational Resources Information Center

    Steiner-Khamsi, Gita

    2007-01-01

    This article presents an interview with Beatrice Beach Szekely, a comparative education scholar that specialized in the Soviet Union. She was editor of the journal "Soviet Education" from 1970 to 1989. During the interview, Szekely talked about how she became personally involved in Russian/Soviet studies of education. She related that her interest…

  7. Creating the Higbee Beach Butterfly Garden.

    ERIC Educational Resources Information Center

    Stiles, Eric, And Others

    1994-01-01

    Recently, the popularity of butterfly watching has skyrocketed, and Higbee Beach Wildlife Management Area has emerged as a mecca. This article describes the site, garden design, vegetation, planting and weeding strategies, and tips for using the garden as a model. Lists bloom periods for plant species used at the garden. (LZ)

  8. Partial characterization of vitellin and localization of vitellogenin production in the terrestrial isopod, Armadillidium vulgare.

    PubMed

    Okuno, A; Katayama, H; Nagasawa, H

    2000-07-01

    Vitellins were purified separately from ovaries and eggs of the isopod, Armadillidium vulgare. Ovarian vitellin consisted of at least six proteins with relative molecular masses of 205, 200, 185, 180, 122 and 112 kDa. The larger four proteins disappeared in eggs within a week after oviposition and a 59-kDa protein appeared thereafter. The amino-terminal amino acid sequences of these vitellin proteins were identical except for the ovarian 112 kDa, egg 112 kDa and 59 kDa proteins, and showed considerable similarity to those of known vitellogenins from other animals. Comparison of tryptic peptide maps of the 122 and 112 kDa proteins from eggs on reversed-phase HPLC and sequence identification of two randomly selected peaks having the same retention times indicated that two peptides were mostly similar in sequence. PCR-assisted cloning of the 5' region of a cDNA (591 bp) encoding vitellogenin revealed the presence of a signal peptide consisting of 16 amino acid residues and clarified the structural relationship among the protein components except for the ovarian 112 kDa and the egg 59 kDa proteins. Northern blot analysis revealed that the fat body is the main vitellogenin producing organ. PMID:11007182

  9. Ommochrome deficiency in an albino strain of a terrestrial isopod, Armadillidium vulgare.

    PubMed

    Hasegawa, Y; Negishi, S; Naito, J; Ikeda, R; Hasegawa, H; Nagamura, Y

    1999-08-01

    In order to clarify the cause of ommochrome deficiency in an albino strain of the terrestrial isopod, Armadillidium vulgare, levels of xanthommatin, 3-hydroxykynurenine, 3-hydroxyanthranilic acid and tryptophan in whole body extracts of the albino and the wild type individuals were determined together with enzyme activities of kynurenine-3-hydroxylase, kynureninase and tryptophan-2,3-dioxygenase. Xanthommatin could not be detected in the albinos. The levels of 3-hydroxykynurenine and 3-hydroxyanthranilic acid were determined by high-performance liquid chromatography (HPLC) with electrochemical detection and were markedly low in the albinos compared with the wild type individuals. In contrast to those, the tryptophan levels determined by HPLC with fluorescence detection did not differ significantly between the two phenotypes. In the albino A. vulgare, kynurenine-3-hydroxylase activity was lower and kynureninase activity was higher than in the wild type, although the differences were not statistically significant. Tryptophan-2,3-dioxygenase activity in the albinos was less than 10% that in the wild type. Thus, ommochrome deficiency in the albino A. vulgare is considered to be caused by the extremely low activity of tryptophan-2,3-dioxygenase. PMID:10454296

  10. Characterization and cDNA cloning of androgenic gland hormone of the terrestrial isopod Armadillidium vulgare.

    PubMed

    Okuno, A; Hasegawa, Y; Ohira, T; Katakura, Y; Nagasawa, H

    1999-10-22

    The sex differentiation in crustaceans is known to be controlled by a peptide hormone called androgenic gland hormone (AGH). AGH was extracted and purified from the androgenic glands (AGs) of the male isopod Armadillidium vulgare by high-performance liquid chromatography. AGH consisted of two peptide chains and their N-terminal amino acid sequences were determined. A cDNA encoding AGH was cloned by PCR and sequenced. The cDNA had an open reading frame of 432 bp, which encoded a preproAGH consisting of a signal peptide (21 residues), B chain (44 residues), C peptide (46 residues), and A chain (29 residues). Through processing, the A and B chains might form a heterodimer interlinked by disulfide bonds. The A chain possessed a putative N-linked glycosylation site. A Northern blot analysis using the cDNA as a probe detected a hybridization signal with 0.8 kb in the RNA preparation only from the AGs. PMID:10529379

  11. Breeding biology and microhabitat utilization of the intertidal isopod Idotea granulosa Rathke, in the Irish Sea

    NASA Astrophysics Data System (ADS)

    Salemaa, Heikki

    1986-03-01

    The life history and distribution of the intertidal isopod Idotea granulosa were investigated at five rocky shore biotopes in the Isle of Man. I. granulosa breeds throughout the year in the Irish Sea. The breeding activity is highest in the early summer after the sexual maturation of the overwintered animals. At that period about 4% of the females were infested by Clypeoniscus sp. (Isopoda) which destroys the brood. A small proportion of the juveniles released in the early summer mature and breed in the autumn. In the winter Idotea populations consisted of juveniles, immature adults and old individuals which produce another brood. These large sized animals die off before the summer. Consequently, the age and size of the breeding I. granulosa fluctuates seasonally. The number of eggs is linearly related to the female length. The fecundity is highest in the spring and lowest in the autumn in all female size classes. I. granulosa inhabits an array of structurally different intertidal algae including the filamentous Cladophora rupestris, understory turfs Gigartina stellata, Laurencia pinnatifida and Corallina officinalis and the fucoids Fucus serratus and Ascophyllum nodosum. The distribution pattern of I. granulosa in examined intertidal communities is modified by the physiognomy of the algal microhabitats, by seasonal and spatial variation in wave agitation and by the breeding cycle of the population itself. Both the life history characteristics and distribution patterns are explained as adaptations to the spatially and temporally heterogeneous intertidal shores.

  12. Feeding by asellote isopods (Crustacea) on foraminifers (Protozoa) in the deep sea

    NASA Astrophysics Data System (ADS)

    Svavarsson, J.; Gudmundsson, G.; Brattegard, T.

    1993-06-01

    Analysis of gut contents of two deep-sea asellote isopod species, Ilyarachna hirticeps and Eurycope inermis (Munnopsidae, Asellota, Isopoda, Crustacea), showed that they were preying on benthic foraminifers. Benthic foraminifers with hard tests were more frequent in I. hirticeps guts than in E. inermis. I. hirticeps, having robust mandibles, is capable of crushing large calcareous and agglutinating foraminifers with hard tests. The presence of foraminiferal fecal pellets (stercomata), along with fine mineral particles and globigerinacean tests in I. hirticeps guts, shows that it was preying on the large, loosely agglutinating foraminifer, Oryctoderma sp. A. E. inermis swallowed whole, medium sized, calcareous foraminifers, which it apparently was unable to crush with its slender mandibles. The guts of E. inermis contained an abundance of mineral particles and globigerinacean tests. These are conjectured to be mashed remains of certain agglutinating foraminifers with soft tests, rather than being evidence of detritivory. It is suggested that feeding on foraminifers by asellotes may be common and may significantly affect the foraminiferal community.

  13. Effect of forced fasting on magnesium and manganese regulation in a terrestrial isopod, Porcellio spinicornis Say

    SciTech Connect

    Bercovitz, K.; Alikhan, M.A. )

    1989-07-01

    The amount of toxic and non-toxic elements assimilated by primary consumers from their environment depends as much on the form, as on concentration of these elements in the food. In superficially contaminated sites, the majority of elements detected in plant material are present as a blanket deposit of fine particles on leaf surfaces, and these are easily removed as the consumed material passes through the alimentary canal. In contrast, trace metals stored in the plant tissue are not readily available as they have been taken up via roots and are firmly bound within the plant tissue. Earlier studies have shown that mean concentrations of magnesium (Mg) and manganese (Mn) in whole woodlice are correlated with levels in their diet. Both metals are regulated by terrestrial isopods during their intermoult- and moult-cycles. The present study provides information on the regulation of Mg and Mn tissue concentrations during forced fasting in adult, intermoult male and female Porcellio spinicornis Say (Porcellionidae, Isopoda). Mg, the principal cation in the soft tissues is a well known activator of many enzymes of the glycolytic systems. Mn, on the other hand, plays a special role in digestive and catabolic processes.

  14. Diel ontogenetic shift in parasitic activity in a gnathiid isopod on Caribbean coral reefs

    NASA Astrophysics Data System (ADS)

    Sikkel, P. C.; Ziemba, R. E.; Sears, W. T.; Wheeler, J. C.

    2009-06-01

    Ontogenetic niche shifts are characteristic of organisms with complex life cycles such as many marine invertebrates. Research has focused primarily on changes in habitat or diet. However, ontogenetic changes can also occur in the temporal pattern of foraging. Gnathiid isopods feed on fish blood throughout their larval stages and are the primary food item for cleaning organisms on coral reefs. At sites in Australia and the Caribbean, gnathiid larvae exhibit size-related differences in diel activity. However, it is unclear whether this is due to interspecific or intraspecific variation in behavior. Fish were deployed in cages near sunset on shallow reefs off St. John, U.S. Virgin Islands and allowed to be infected with larval gnathiids. Larvae collected from fish retrieved near midnight developed into adults, with most developing into females. In contrast, approximately 80% of gnathiids collected after first light developed into second or third stage larvae, and nearly all of the remaining, large, individuals developed into males. Comparison of ITS2 gene regions from individuals collected in emergence traps from the same reefs during the day versus during the night revealed no differences in this highly variable region. Thus, gnathiid larvae at this locality shift their time of activity as they develop, and larvae developing into males remain active over a longer time period than those developing into females.

  15. Metapopulation structure of the marine isopod Idotea metallica, a species associated with drifting habitat patches

    NASA Astrophysics Data System (ADS)

    Gutow, L.; Franke, H.-D.

    2002-12-01

    The neustonic isopod Idotea metallica inhabits objects drifting at the sea surface. Animals found on floating patches represent not just ephemeral assemblages but persistent local populations. Drift material collected in the Mediterranean, the North Atlantic, and the North Sea harboured populations of up to about 50 animals including all developmental stages. In laboratory experiments the species proved to be able to establish populations on spatially limited, isolated substrates. The capacity of 5-litre-microcosms for I. metallica was about 130 animals. In the presence of the coastally distributed congener Idotea baltica, however, laboratory populations of I. metallica went extinct within 12 weeks. Even though high colonisation rates can be expected in coastal waters because of high patch densities, metapopulation persistence is mostly restricted to the open sea. In coastal waters extinction rate of local populations increases because of patch destruction and the species' inferiority to coastally distributed competitors. Due to high uncertainties in estimating patch densities, it is difficult to determine the parameters underlying metapopulation dynamics such as the migration rate and the rate of patch occupancy.

  16. Masculinization of female isopods (Crustacea) correlated with non-Mendelian inheritance of cytoplasmic viruses.

    PubMed Central

    Juchault, P; Louis, C; Martin, G; Noulin, G

    1991-01-01

    When in genetic females external male characters differentiate, the phenomenon is called "male pseudohermaphroditism." This male differentiation occurs in terrestrial isopods (Crustacea, suborder Oniscoidea) and sometimes involves only some epithelial areas (gynandromorphous mosaics). It is not induced by male hormones or by abnormal ovary function. This intersexuality is transmitted maternally (by the intersex females) or paternally (by the brothers of intersex females) to between 30% and 60% of their offspring. Although it occurs at 20 degrees C, the male differentiation disappears when breeding takes place at 27 degrees C. Male characters differentiate in normal females--even in other Oniscoidea species (Porcellio dilatatus, Porcellio laevis, Armadillidium vulgare)--after injection of a 0.22-micron filtered tissue extract. Since an inhibitor of bacterial protein synthesis (gentamycin) does not inhibit this masculinizing effect, we infer that neither organelles nor bacteria are involved. Intersexuality is always correlated with the presence of cytoplasmic viral particles in both intersex-female and transmitter-male tissues. Striking similarities to the Drosophila S virus are noted. A reovirus-like Oniscoidea masculinizing virus, which probably acts only on the epithelial areas sensitive to the male hormones, is most likely the causative agent of this intersexuality. Here we report the conversion of secondary sexual characters putatively caused by a virus. Images PMID:11607243

  17. Cardioacceleratory Neurons of the Isopod Crustacean, Ligia exotica: Visualization of Peripheral Projection onto the Heart Muscle.

    PubMed

    Sakurai, A; Yamagishi, H

    1998-01-01

    Innervation of the heart muscle by the cardioacceleratory neurons was morphologically and electrophysiologically examined in the isopod crustacean, Ligia exotica. Intracellular injection of neurobiotin into the first and second cardioacceleratory neurons (CA1 and CA2) revealed their peripheral axonal projections. Inside the heart, the CA1 and CA2 axons ran along the trunk of the cardiac ganglion. Finely arborized branches with many varicosities arose from the axon and projected over the heart muscle. Stimulation of either the CA1 or CA2 axon caused an overall depolarization in the muscle of a quiescent heart. The amplitude of the depolarization increased with increasing stimulus frequency. During stimulation, the membrane resistance of the heart muscle decreased. In a beating heart, the cardioacceleratory nerve stimulation caused multiple effects on the heart muscle activity and the heartbeat. The results suggest that the cardioacceleratory neurons of Ligia exotica regulate the amplitude of the heartbeat (inotropic effect) and the heart tonus (tonotropic effect) via the synaptic contacts on the heart muscle, while the heartbeat frequency (chronotropic effect) is regulated via the synapses on the cardiac ganglion neurons. PMID:18429668

  18. Glutamatergic neuromuscular transmission in the heart of the isopod crustacean Ligia exotica.

    PubMed

    Sakurai; Mori; Yamagishi

    1998-09-22

    Neuromuscular transmission between the cardiac ganglion (CG) and the myocardium was examined in the adult heart of the isopod crustacean Ligia exotica. Intracellular injection of neurobiotin into the CG neurones revealed that all six CG neurones send their axons onto the cardiac muscle, where they form axon terminals bearing varicosities. All the CG neurones and their processes exhibited glutamate-like immunoreactivity. The cardiac muscle showed depolarizing membrane potential responses to glutamate applied focally to sites close to axon terminals bearing varicosities. Both the glutamate-induced response and the excitatory junctional potential (EJP) showed desensitization in response to the repeated application of glutamate. Under voltage-clamp conditions, the cardiac muscle produced inward current responses to focally applied glutamate. The reversal potential for the glutamate-induced current estimated from extrapolation of the linear current/voltage relationship was similar to that of the excitatory junctional current evoked by ganglionic nerve stimulation. Both the glutamate-induced response and the EJP were blocked by a glutamate-specific antagonist, Joro spider toxin. These results led us to conclude that the CG neurones of Ligia exotica are glutamatergic motoneurones. PMID:9739066

  19. Dual effects of dopamine on the adult heart of the isopod crustacean Ligia exotica.

    PubMed

    Yamagishi, Hiroshi; Takano, Satoshi; Tanaka, Kosuke

    2004-01-01

    In the adult heart of the isopod crustacean Ligia exotica, the cardiac ganglion acts as the primary pacemaker with the myocardium having a latent pacemaker property. We show several lines of evidence that dopamine modulates the heartbeat of adult L. exotica affecting both pacemaker sites in the heart. Dopamine caused positive chronotropic (frequency increase) and inotropic (amplitude increase) effects on the heartbeat in a concentration dependent manner. The time courses of these effects were considerably different and the inotropic effect appeared later and lasted longer than the chronotropic effect. Dopamine rapidly increased the frequency of the bursting activity in the cardiac ganglion neurons and each impulse burst of the cardiac ganglion was always followed by a heartbeat. Moreover, dopamine slowly increased the amplitude and duration of the action potential plateau (plateau potential) of the myocardium. When the myocardial pacemaker activity was induced by application of tetrodotoxin, which suppresses cardiac ganglion activity, dopamine slowly increased the amplitude and duration of the myocardial plateau potential while decreasing its frequency. These results suggest that dopamine modulates the heartbeat in adult L. exotica producing a dual effect on the two pacemaker sites in the heart, the cardiac ganglion and myocardium. PMID:14745099

  20. Transfer of the heart pacemaker during juvenile development in the isopod crustacean Ligia exotica.

    PubMed

    Yamagishi, H; Hirose, E

    1997-09-01

    Developmental changes in heartbeat pacemaker mechanisms were examined electrophysiologically in the isopod crustacean Ligia exotica. The heartbeat of embryos and early juveniles was myogenic. The heart muscle cells were coupled electrically, and no localized pacemaker activity was found in the heart. In newly hatched juveniles, the cardiac ganglion exhibited no spontaneous activity, although stimulation of the cardiac ganglion produced excitatory junctional potentials (EJPs) in the heart muscle. The myogenic activity of the heart was reset and entrained by the EJPs evoked by ganglionic stimulation. During juvenile development, spontaneous EJPs appeared irregularly in the heart muscle. Later in development, the cardiac ganglion started rhythmic bursting, and each muscle response followed a ganglionic burst discharge and overlapped the EJPs evoked by ganglionic activity. At this point, the activity of the cardiac ganglion was suppressed by application of tetrodotoxin (TTX); however, even in old adults, both muscle activity and the heartbeat continued following TTX application. Heartbeat frequency was lower in TTX-containing saline than in normal saline. These results show that, during juvenile development, the heart pacemaker is transferred from the heart muscle to the cardiac ganglion, which becomes the primary pacemaker and entrains the heart muscle activity to a higher frequency via EJPs. PMID:9343853

  1. Developmental changes in heart photosensitivity of the isopod crustacean Ligia exotica.

    PubMed

    Miyamoto, Hiroshi; Horiguchi, Hiroko; Hariyama, Takahiko; Yamagishi, Hiroshi

    2007-03-01

    During juvenile development, the cardiac pacemaker of the isopod crustacean Ligia exotica is transferred from the myocardium to the cardiac ganglion of the neurogenic heart. In adult, light stimulus decreases the beat frequency of the heart. To elucidate developmental changes in the photosensitivity of the juvenile Ligia heart, we examined the effect of a light stimulus on the semi-isolated heart of juveniles at various developmental stages by the recording membrane potential of the myocardium. We also examined the effect of hyperpolarizing current injection into the myocardium, because this causes different effects on the beat frequency between myogenic and neurogenic hearts. In newly hatched juveniles, beat frequency decreased upon current injection but exhibited no response to white light. In contrast, 10 days after hatching, beat frequency did not change upon current injection, but decreased in response to white light. The heart photoresponse of juveniles was reversibly eliminated by application of tetrodotoxin, which changes the heartbeat from neurogenic to myogenic by suppressing cardiac ganglion activity. The proportion of juveniles exhibiting a heart photoresponse increased gradually up to 100% during the period between 3 and 10 days after hatching. The results suggest that the heart photoresponse of L. exotica appears in association with transfer of the cardiac pacemaker from the myocardium to the cardiac ganglion during juvenile development. PMID:17551248

  2. Organization of the large mitochondrial genome in the isopod Armadillidium vulgare.

    PubMed Central

    Raimond, R; Marcadé, I; Bouchon, D; Rigaud, T; Bossy, J P; Souty-Grosset, C

    1999-01-01

    The mitochondrial DNA (mtDNA) in animals is generally a circular molecule of approximately 15 kb, but there are many exceptions such as linear molecules and larger ones. RFLP studies indicated that the mtDNA in the terrestrial isopod Armadillidium vulgare varied from 20 to 42 kb. This variation depended on the restriction enzyme used, and on the restriction profile generated by a given enzyme. The DNA fragments had characteristic electrophoretic behaviors. Digestions with two endonucleases always generated fewer fragments than expected; denaturation of restriction profiles reduced the size of two bands by half; densitometry indicated that a number of small fragments were present in stoichiometry, which has approximately twice the expected concentration. Finally, hybridization to a 550-bp 16S rDNA probe often revealed two copies of this gene. These results cannot be due to the genetic rearrangements generally invoked to explain large mtDNA. We propose that the large A. vulgare mtDNA is produced by the tripling of a 14-kb monomer with a singular rearrangement: one monomer is linear and the other two form a circular dimer. Densitometry suggested that these two molecular structures were present in different proportions within a single individual. The absence of mutations within the dimers also suggests that replication occurs during the monomer phase. PMID:9872960

  3. Cannibalism and predation as paths for horizontal passage of Wolbachia between terrestrial isopods.

    PubMed

    Le Clec'h, Winka; Chevalier, Frédéric D; Genty, Lise; Bertaux, Joanne; Bouchon, Didier; Sicard, Mathieu

    2013-01-01

    The alpha-proteobacteria Wolbachia are the most widespread endosymbionts in arthropods and nematodes. Mainly maternally inherited, these so-called sex parasites have selected several strategies that increase their vertical dispersion in host populations. However, the lack of congruence between the Wolbachia and their host phylogenies suggests frequent horizontal transfers. One way that could be used for horizontal Wolbachia transfers between individuals is predation. The aim of this study was to test whether horizontal passage of Wolbachia is possible when an uninfected terrestrial isopod eats an infected one. After having eaten Armadillidium vulgare harbouring Wolbachia, the predator-recipients (the two woodlice A. vulgare and Porcellio dilatatus dilatatus) that were initially Wolbachia-free were tested positive for the presence of Wolbachia both by quantitative PCR and Fluorescence in situ Hybridization (FISH). Even if the titers were low compared to vertically infected individuals, this constitutes the first demonstration of Wolbachia occurrence in various organs of an initially uninfected host after eating an infected one. PMID:23593179

  4. Inverted repeats and genome architecture conversions of terrestrial isopods mitochondrial DNA.

    PubMed

    Doublet, Vincent; Helleu, Quentin; Raimond, Roland; Souty-Grosset, Catherine; Marcadé, Isabelle

    2013-09-01

    Mitochondrial DNA (mtDNA) is usually depicted as a circular molecule, however, there is increasing evidence that linearization of mtDNA evolved independently many times in organisms such as fungi, unicellular eukaryotes, and animals. Recent observations in various models with linear mtDNA revealed the presence of conserved inverted repeats (IR) at both ends that, when they become single-stranded, may be able to fold on themselves to create telomeric-hairpins involved in genome architecture conversions. The atypical mtDNA of terrestrial isopods (Crustacea: Oniscidea) composed of linear monomers and circular dimers is an interesting model to study genome architecture conversions. Here, we present the mtDNA control region sequences of two species of the genus Armadillidium: A. vulgare and A. pelagicum. All features of arthropods mtDNA control regions are present (origin of replication, poly-T stretch, GA and TA-rich blocks and one variable domain), plus a conserved IR. This IR can potentially fold into a hairpin structure and is present in two different orientations among the A. vulgare populations: either in one sense or in its reverse complement. This polymorphism, also observed in a single individual (heteroplasmy), might be a signature of genome architecture conversions from linear to circular monomeric mtDNA via successive opening and closing of the molecules. PMID:24068302

  5. Diel variation in ammonia excretion, glutamine levels, and hydration status in two species of terrestrial isopods.

    PubMed

    Wright, Jonathan C; Peña-Peralta, Mariasol

    2005-01-01

    Terrestrial isopods (suborder Oniscidea) excrete most nitrogen diurnally as volatile ammonia, and ammonia-loaded animals accumulate nonessential amino acids, which may constitute the major nocturnal nitrogen pool. This study explored the relationship between ammonia excretion, glutamine storage/mobilization, and water balance, in two sympatric species Ligidium lapetum (section Diplocheta), a hygric species; and Armadillidium vulgare (Section Crinocheta), a xeric species capable of water-vapor absorption (WVA). Ammonia excretion (12-h), tissue glutamine levels, and water contents were measured following field collection of animals at dusk and dawn. In both species, diurnal ammonia excretion exceeded nocturnal excretion four- to fivefold while glutamine levels increased four- to sevenfold during the night. Most glutamine was accumulated in the somatic tissues ("body wall"). While data support the role of glutamine in nocturnal nitrogen storage, potential nitrogen mobilization from glutamine breakdown (162 micromol g(-1) in A. vulgare) exceeds measured ammonia excretion (2.5 micromol g(-1)) over 60-fold. This may serve to generate the high hemolymph ammonia concentrations (and high P(NH3)) seen during volatilization. The energetic cost of ammonia volatilization is discussed in the light of these findings. Mean water contents were similar at dusk and dawn in both species, indicating that diel cycles of water depletion and replenishment were not occurring. PMID:15578188

  6. Variations of immune parameters in terrestrial isopods: a matter of gender, aging and Wolbachia.

    PubMed

    Sicard, Mathieu; Chevalier, Frédéric; De Vlechouver, Mickaël; Bouchon, Didier; Grève, Pierre; Braquart-Varnier, Christine

    2010-09-01

    Ecological factors modulate animal immunocompetence and potentially shape the evolution of their immune systems. Not only environmental parameters impact on immunocompetence: Aging is one major cause of variability of immunocompetence between individuals, and sex-specific levels of immunocompetence have also been frequently described. Moreover, a growing core of data put in light that vertically transmitted symbionts can dramatically modulate the immunocompetence of their hosts. In this study, we addressed the influence of gender, age and the feminising endosymbiont Wolbachia (wVulC) on variations in haemocyte density, total PO activity and bacterial load in the haemolymph of the terrestrial isopod Armadillidium vulgare. This host-symbiont system is of particular interest to address this question since: (1) wVulC was previously shown as immunosuppressive in middle-aged females and (2) wVulC influences sex determination. We show that age, gender and Wolbachia modulate together immune parameters in A. vulgare. However, wVulC, which interacts with aging, appears to be the prominent factor interfering with both PO activity and haemocyte density. This interference with immune parameters is not the only aspect of wVulC virulence on its host, as reproduction and survival are also altered. PMID:20676599

  7. Evidence for recombination between feminizing Wolbachia in the isopod genus Armadillidium.

    PubMed

    Verne, Sébastien; Johnson, Monique; Bouchon, Didier; Grandjean, Frédéric

    2007-08-01

    Wolbachia are maternally inherited endosymbiotic alpha-Proteobacteria infecting a wide range of arthropods. Wolbachia induce feminization in many terrestrial isopod species, particularly in the genus Armadillidium (Crustacea, Oniscidea). The diversity of Wolbachia strains infecting Armadillidium species was examined. Results reveal that natural populations of A. vulgare contain three different Wolbachia strains (wVulC, wVulM and wVulP). The wsp gene and its 3'-adjacent region show evidence that two recombination events have occurred between two of these strains. In both cases, multiple statistical analyses suggest that a small gene fragment of a strain closely related to wVulM (minor parent) is inserted into the genome of another strain closely related to wVulC (major parent). Although multiple infections in a single individual have never been demonstrated in natural population, the existence of recombination between feminizing strains suggests that bi-infections are possible, or at least that bi-infections can be maintained sufficiently long enough to allow recombination. Recombination events increase genetic diversity of Wolbachia found in Armadillidium species and may play a role in the ability of Wolbachia strains to invade new hosts. PMID:17537593

  8. Cation regulation by the terrestrial isopod Armadillidium vulgare (Crustacea: Isopoda: Oniscidea) during dehydration in air.

    PubMed

    Koh, Huishan; Wright, Jonathan

    2011-06-01

    Many terrestrial arthropods display tight osmotic and ionic regulation of the hemolymph during dehydration. In this study, we sought to quantify the level of regulation of the major hemolymph cations in the terrestrial isopod Armadillidium vulgare (Isopoda, Oniscidea). Inulin space measurements showed that the hemolymph comprises 52 ± 2.2% of the hydrated water content but contributes 71 ± 9.8% of water losses during desiccation. Hemolymph concentrations of Na+, K+ and Ca²+ were measured in variably dehydrated animals using ion-selective microelectrodes and compared with predicted concentrations assuming no regulation. Na+ and Ca²+ are quite tightly regulated, showing respective concentration increases of 20.8% and 7.1% following a 50% reduction in hemolymph volume, but K+ showed no measurable regulation. The excreted cation fraction during desiccation is negligible. Sites of ion sequestration were examined by injecting ²²Na and ⁴⁵Ca into the hemolymph of hydrated animals and assaying tissue-specific activities following dehydration. Na+ is apparently sequestered non-specifically by an unknown mechanism. Ca²+ accumulates in the dorsal somatic tissues, possibly in the calcium pool of the cuticle. How A. vulgare avoids significant disruptions of E(m) and neuromuscular function in the absence of K+ regulation, and how it sequesters Na+, both pose intriguing challenges for future work. PMID:21335098

  9. Multi-infections of feminizing Wolbachia strains in natural populations of the terrestrial isopod Armadillidium vulgare.

    PubMed

    Valette, Victorien; Bitome Essono, Paul-Yannick; Le Clec'h, Winka; Johnson, Monique; Bech, Nicolas; Grandjean, Frédéric

    2013-01-01

    Maternally inherited Wolbachia (α-Proteobacteria) are widespread parasitic reproductive manipulators. A growing number of studies have described the presence of different Wolbachia strains within a same host. To date, no naturally occurring multiple infections have been recorded in terrestrial isopods. This is true for Armadillidium vulgare which is known to harbor non simultaneously three Wolbachia strains. Traditionally, such Wolbachia are detected by PCR amplification of the wsp gene and strains are characterized by sequencing. The presence of nucleotide deletions or insertions within the wsp gene, among these three different strains, provides the opportunity to test a novel genotyping method. Herein, we designed a new primer pair able to amplify products whose lengths are specific to each Wolbachia strain so as to detect the presence of multi-infections in A. vulgare. Experimental injections of Wolbachia strains in Wolbachia-free females were used to validate the methodology. We re-investigated, using this novel method, the infection status of 40 females sampled in 2003 and previously described as mono-infected based on the classical sequencing method. Among these females, 29 were identified as bi-infected. It is the first time that naturally occurring multiple infections of Wolbachia are detected within an individual A. vulgare host. Additionally, we resampled 6 of these populations in 2010 to check the infection status of females. PMID:24324814

  10. Multi-Infections of Feminizing Wolbachia Strains in Natural Populations of the Terrestrial Isopod Armadillidium Vulgare

    PubMed Central

    Valette, Victorien; Bitome Essono, Paul-Yannick; Le Clec’h, Winka; Johnson, Monique; Bech, Nicolas; Grandjean, Frédéric

    2013-01-01

    Maternally inherited Wolbachia (α-Proteobacteria) are widespread parasitic reproductive manipulators. A growing number of studies have described the presence of different Wolbachia strains within a same host. To date, no naturally occurring multiple infections have been recorded in terrestrial isopods. This is true for Armadillidium vulgare which is known to harbor non simultaneously three Wolbachia strains. Traditionally, such Wolbachia are detected by PCR amplification of the wsp gene and strains are characterized by sequencing. The presence of nucleotide deletions or insertions within the wsp gene, among these three different strains, provides the opportunity to test a novel genotyping method. Herein, we designed a new primer pair able to amplify products whose lengths are specific to each Wolbachia strain so as to detect the presence of multi-infections in A. vulgare. Experimental injections of Wolbachia strains in Wolbachia-free females were used to validate the methodology. We re-investigated, using this novel method, the infection status of 40 females sampled in 2003 and previously described as mono-infected based on the classical sequencing method. Among these females, 29 were identified as bi-infected. It is the first time that naturally occuring multiple infections of Wolbachia are detected within an individual A. vulgare host. Additionally, we resampled 6 of these populations in 2010 to check the infection status of females. PMID:24324814

  11. The glycosylated androgenic hormone of the terrestrial isopod Porcellio scaber (Crustacea).

    PubMed

    Grève, Pierre; Braquart-Varnier, Christine; Strub, Jean-Marc; Félix, Christine; Van Dorsselaer, Alain; Martin, Gilbert

    2004-05-01

    It appears from grafting experiments that the androgenic hormone (AH) of terrestrial isopods has a narrow species-specificity [J. Crust. Biol. 19 (1999) 684], even if AH of different species shared common epitopes [Gen. Comp. Endocrinol. 125 (2002) 218]. To date only the glycosylated AH of the woodlouse Armadillidium vulgare has been deciphered by us [Ann. New York Acad. Sci. 839 (1998) 111; Eur. J. Biochem. 262 (1999) 727] and [Biochem. Biophys. Res. Commun. 264 (1999) 419] have confirmed the primary structure of this protein. We reported in the present paper the characterization of the AH in another species Porcellio scaber by a combination of microsequencing, mass spectrometry, and molecular cloning. We found only one glycoform which consisted of two peptide chains, A and B, of 31 and 44 amino acids, respectively, with A chain carrying on Asn18 a N-glycosylated moiety, size of which has been determined by MALDI-MS measurements. The expected structure of the glycosylation was proposed. The deduced amino acid sequence of the AH precursor was mainly identical to the one obtained independently by another group [Zool. Sci. 20 (2003) 75]. We also showed that AH gene is exclusively expressed in androgenic glands. Sequence comparison with A. vulgare and P. scaber (population of Japan) AH was discussed. PMID:15081839

  12. Cannibalism and Predation as Paths for Horizontal Passage of Wolbachia between Terrestrial Isopods

    PubMed Central

    Le Clec’h, Winka; Chevalier, Frédéric D.; Genty, Lise; Bertaux, Joanne; Bouchon, Didier; Sicard, Mathieu

    2013-01-01

    The alpha-proteobacteria Wolbachia are the most widespread endosymbionts in arthropods and nematodes. Mainly maternally inherited, these so-called sex parasites have selected several strategies that increase their vertical dispersion in host populations. However, the lack of congruence between the Wolbachia and their host phylogenies suggests frequent horizontal transfers. One way that could be used for horizontal Wolbachia transfers between individuals is predation. The aim of this study was to test whether horizontal passage of Wolbachia is possible when an uninfected terrestrial isopod eats an infected one. After having eaten Armadillidium vulgare harbouring Wolbachia, the predator-recipients (the two woodlice A. vulgare and Porcellio dilatatus dilatatus) that were initially Wolbachia-free were tested positive for the presence of Wolbachia both by quantitative PCR and Fluorescence in situ Hybridization (FISH). Even if the titers were low compared to vertically infected individuals, this constitutes the first demonstration of Wolbachia occurrence in various organs of an initially uninfected host after eating an infected one. PMID:23593179

  13. Variations of immune parameters in terrestrial isopods: a matter of gender, aging and Wolbachia

    NASA Astrophysics Data System (ADS)

    Sicard, Mathieu; Chevalier, Frédéric; de Vlechouver, Mickaël; Bouchon, Didier; Grève, Pierre; Braquart-Varnier, Christine

    2010-09-01

    Ecological factors modulate animal immunocompetence and potentially shape the evolution of their immune systems. Not only environmental parameters impact on immunocompetence: Aging is one major cause of variability of immunocompetence between individuals, and sex-specific levels of immunocompetence have also been frequently described. Moreover, a growing core of data put in light that vertically transmitted symbionts can dramatically modulate the immunocompetence of their hosts. In this study, we addressed the influence of gender, age and the feminising endosymbiont Wolbachia ( wVulC) on variations in haemocyte density, total PO activity and bacterial load in the haemolymph of the terrestrial isopod Armadillidium vulgare. This host-symbiont system is of particular interest to address this question since: (1) wVulC was previously shown as immunosuppressive in middle-aged females and (2) wVulC influences sex determination. We show that age, gender and Wolbachia modulate together immune parameters in A. vulgare. However, wVulC, which interacts with aging, appears to be the prominent factor interfering with both PO activity and haemocyte density. This interference with immune parameters is not the only aspect of wVulC virulence on its host, as reproduction and survival are also altered.

  14. Molecular insight into lignocellulose digestion by a marine isopod in the absence of gut microbes

    PubMed Central

    King, Andrew J.; Cragg, Simon M.; Li, Yi; Dymond, Jo; Guille, Matthew J.; Bowles, Dianna J.; Bruce, Neil C.; Graham, Ian A.; McQueen-Mason, Simon J.

    2010-01-01

    The digestion of lignocellulose is attracting attention both in terms of basic research into its metabolism by microorganisms and animals, and also as a means of converting plant biomass into biofuels. Limnoriid wood borers are unusual because, unlike other wood-feeding animals, they do not rely on symbiotic microbes to help digest lignocellulose. The absence of microbes in the digestive tract suggests that limnoriid wood borers produce all the enzymes necessary for lignocellulose digestion themselves. In this study we report that analysis of ESTs from the digestive system of Limnoria quadripunctata reveals a transcriptome dominated by glycosyl hydrolase genes. Indeed, > 20% of all ESTs represent genes encoding putative cellulases, including glycosyl hydrolase family 7 (GH7) cellobiohydrolases. These have not previously been reported in animal genomes, but are key digestive enzymes produced by wood-degrading fungi and symbiotic protists in termite guts. We propose that limnoriid GH7 genes are important for the efficient digestion of lignocellulose in the absence of gut microbes. Hemocyanin transcripts were highly abundant in the hepatopancreas transcriptome. Based on recent studies indicating that these proteins may function as phenoloxidases in isopods, we discuss a possible role for hemocyanins in lignin decomposition. PMID:20212162

  15. Spermiophagic activity in the female genital system of some species of terrestrial isopods (Crustacea, Halophilosciidae).

    PubMed

    Mazzei, Veronica; Longo, Guglielmo; Brundo, Maria Violetta

    2014-08-01

    The females of some species of the family Halophilosciidae receive in the course of mating a quantity of sperm considerably redundant with respect to the number of eggs that can be fertilized; this is possible thanks to the peculiar morpho-functional organization that characterizes their genital system and that allows them to store the sperm not only in the great seminal receptacle but also within the ovary. While most of the sperm stay free in the lumen of the seminal receptacle, a part of those present in the ovary undergoes a process of capture by the follicular cells with consequent internalization within endocellular cavities. This process concerns exclusively the immotile tail, that characterizes the peculiar spermatozoon of the isopods and which is essentially of proteic nature. After their capture the sperm tails undergo a gradual process of digestion, which seems to be apparently realized without the intervention of lysosomes. The possible role of this spermiophagic activity might be to represent a significant trophic paternal investment aimed at improving the fitness of the female and of the offsprings. PMID:24947800

  16. The role of different reproductive barriers during phenotypic divergence of isopod ecotypes.

    PubMed

    Eroukhmanoff, Fabrice; Hargeby, Anders; Svensson, Erik I

    2011-09-01

    The question of how diverging populations become separate species by restraining gene flow is a central issue in evolutionary biology. Assortative mating might emerge early during adaptive divergence, but the role of other types of reproductive barriers such as migration modification have recently received increased attention. We demonstrate that two recently diverged ecotypes of a freshwater isopod (Asellus aquaticus) have rapidly developed premating isolation, and this isolation barrier has emerged independently and in parallel in two south Swedish lakes. This is consistent with ecological speciation theory, which predicts that reproductive isolation arises as a byproduct of ecological divergence. We also find that in one of these lakes, habitat choice acts as the main barrier to gene flow. These observations and experimental results suggest that migration modification might be as important as assortative mating in the early stages of ecological speciation. Simulations suggest that the joint action of these two isolating barriers is likely to greatly facilitate adaptive divergence, compared to if each barrier was acting alone. PMID:21884061

  17. Male dimorphism in the harem-forming gnathiid isopod Elaphognathia discolor (Crustacea: Isopoda).

    PubMed

    Tanaka, Katsuhiko; Nishi, Eijiroh

    2011-08-01

    Previously unreported males of a gnathiid isopod were found in reproductive aggregations of the harem-forming gnathiid Elaphognathia discolor. Although the male gnathiids were small in size and morphologically different from E. discolor males, the male sexual organ, appendix masculina, was similar to that of E. discolor males, and possible conspecific larvae and females of the small male gnathiid were never found. In the laboratory, the small male gnathiids as well as male E. discolor successfully copulated with female E. discolor, and the development of embryos in female brood pouches was observed. Offspring of small male gnathiids develop to adults of E. discolor after molting three times, or small male gnathiids after molting two times. Thus, the small male gnathiid was concluded to be an alternative male form compared to the regular large male form of E. discolor. This male polymorphism was thought to have a genetic basis, since no small male specimens appeared in offspring of regular E. discolor males. Field sampling showed that a regular large male formed a harem composed of one large male and several females and never coexisted with other large males as previously reported. However, small males were often found together with large males. Therefore, small males are thought to be sneakers intruding into harems dominated by large males. PMID:21800999

  18. Slope and deep-sea abundance across scales: Southern Ocean isopods show how complex the deep sea can be

    NASA Astrophysics Data System (ADS)

    Kaiser, Stefanie; Barnes, David K. A.; Brandt, Angelika

    2007-08-01

    How animals are distributed in the world's largest surface environment, the deep sea, is poorly understood. The ANDEEP (ANtarctic benthic DEEP-sea biodiversity, colonisation history and recent community patterns) III cruise probed richness and abundance of one group, peracarid crustaceans (isopods, amphipods, cumaceans, tanaidaceans, mysidaceans), as a model of deep-sea fauna across Southern Ocean (SO) sites. Analysis of samples from the ANDEEP cruises reveals SO isopods to be highly abundant, rich and endemic as many other taxa in the region are known to be. Samples taken across three spatial scales include sites tens, hundreds and thousands of kilometers apart, sites stretching from the Southern Cape Basin (South Atlantic) to continental Antarctica and including depths from 1030 to 5000 m. Across these spatial scales we investigated ecological success (abundance) of peracarids at order, family, and species levels. Remarkably no significant relationship was found between abundance and spatial scale at any taxonomic level. That is, the variability in abundance at major regional scale is no different to that across just tens of kilometres. Most taxa were represented in only a few samples, but we suggest most inhabitants of the deep Weddell Sea environment to be very patchy rather than rare. Separate plots of family, genus, and species abundance by sample number revealed this to be true—nearly all genera and species are an order of magnitude more abundant than 'background' levels in just one or two samples. Our isopod and amphipod samples reveal the Atlantic sector of the SO, one of the most dynamic and important regions influencing the global deep-sea environment, to be highly complex. Our study suggests that, at least with regard to the study taxa and area, the typical comparisons of regions that are made by ecologists miss the scale at which crucial ecological variability happens. Even without ice scours creating topographical complexity (as on the shelf) the deep Weddell Sea is clearly complex at scales smaller than that measured to date.

  19. Long-term toxicity of five polycyclic aromatic hydrocarbons for the terrestrial isopods Oniscus asellus and Porcellio scaber

    SciTech Connect

    Brummelen, T.C. van; Gestel, C.A.M. van; Verweij, R.A.

    1996-07-01

    Polycyclic aromatic hydrocarbons (PAHs) are a common component of soil pollution, yet little is known of the ecotoxicological risks these compounds may pose to life in soil. This article reports the ecotoxicity of five PAHs for two terrestrial isopod species. Isopods were exposed to food contaminated with four different concentrations of either fluorene, phenanthrene, fluoranthene (up to 4 {micro}mol/g), benz[a]anthracene, or benzo[a]pyrene (up to 1.25 {micro}mol/.g). Exposure of Porcellio scaber lasted 16 weeks, and no adverse effects on survival, growth, or total protein (only females tested) were observed in any of the treatments. A small but significant reduction in growth of Oniscus asellus was observed at 47 weeks of exposure to 0.125 {micro}mol benz[a]anthracene-g{sup {minus}1} dry weight and higher concentrations. A significant stimulation of the reproduction of O. asellus was observed in some of the phenanthrene, fluoranthene, benz[a]anthracene, and benzo[a]pyrene treatments; a larger proportion of the females were gravid, which resulted in a higher number of juveniles per female. Exposure did not significantly affect brood size, weight of the mother after release of the juveniles, or the survival of the juveniles upon starvation. Total protein content of females was significantly reduced at 0.4 {micro}mol fluorene g{sup {minus}1} dry weight and higher concentrations. Growth and protein content of isopods is likely to be affected by PAH exposure only at highly contaminated sites. The ecological consequences of stimulated reproduction and possible DNA damage are poorly understood and require further attention because soil invertebrates may be exposed to PAHs over many generations.

  20. Contrasting phylogeography of sandy vs. rocky supralittoral isopods in the megadiverse and geologically dynamic Gulf of California and adjacent areas.

    PubMed

    Hurtado, Luis A; Lee, Eun Jung; Mateos, Mariana

    2013-01-01

    Phylogeographic studies of animals with low vagility and restricted to patchy habitats of the supralittoral zone, can uncover unknown diversity and shed light on processes that shaped evolution along a continent's edge. The Pacific coast between southern California and central Mexico, including the megadiverse Gulf of California, offers a remarkable setting to study biological diversification in the supralittoral. A complex geological history coupled with cyclical fluctuations in temperature and sea level provided ample opportunities for diversification of supralittoral organisms. Indeed, a previous phylogeographic study of Ligia, a supralittoral isopod that has limited dispersal abilities and is restricted to rocky patches, revealed high levels of morphologically cryptic diversity. Herein, we examined phylogeographic patterns of Tylos, another supralittoral isopod with limited dispersal potential, but whose habitat (i.e., sandy shores) appears to be more extensive and connected than that of Ligia. We conducted Maximum Likelihood and Bayesian phylogenetic analyses on mitochondrial and nuclear DNA sequences. These analyses revealed multiple highly divergent lineages with discrete regional distributions, despite the recognition of a single valid species for this region. A traditional species-diagnostic morphological trait distinguished several of these lineages. The phylogeographic patterns of Tylos inside the Gulf of California show a deep and complex history. In contrast, patterns along the Pacific region between southern California and the Baja Peninsula indicate a recent range expansion, probably postglacial and related to changes in sea surface temperature (SST). In general, the phylogeographic patterns of Tylos differed from those of Ligia. Differences in the extension and connectivity of the habitats occupied by Tylos and Ligia may account for the different degrees of population isolation experienced by these two isopods and their contrasting phylogeographic patterns. Identification of divergent lineages of Tylos in the study area is important for conservation, as some populations are threatened by human activities. PMID:23844103

  1. Bioaccumulation of cadmium and lead and its effects on hepatopancreas morphology in three terrestrial isopod crustacean species.

    PubMed

    Mazzei, V; Longo, G; Brundo, M V; Sinatra, F; Copat, C; Oliveri Conti, G; Ferrante, M

    2014-12-01

    This study was designed to compare cadmium (Cd) and lead (Pb) bioaccumulation in three species of oniscidean isopods - Armadillidium granulatum Brandt, Armadillidium vulgare (Latreille) and Porcellio laevis Latreille which were exposed for three weeks to a contaminated diet, and to determine the morphological and ultrastructural changes in hepatopancreas. Metal accumulation, determined by Inductively Coupled Plasma Mass Spectrometry (ICP-MS), was linearly associated with the exposed concentration and was a function of the metal and the species tested. All three species accumulated lower levels of Pb than Cd. A. vulgare accumulated the largest concentration of Pb, especially at the higher doses, whereas P. laevis showed the greatest Cd accumulation, and the highest Cd concentration was lethal for all exposed species. The highest concentrations of Pb and Cd induced significant changes both in the general morphology of tubules and in the ultrastructural organization of epithelial cells in hepatopancreas. Some Pb/Cd induced alterations include: brush border disorganization; reduction of the basal labyrinth formed by the plasma membrane; condensation of some cytoplasm areas and of chromatin; rough endoplasmic reticulum and mitochondrial alterations; increase of secondary lysosomes and of type B granules in S cells. Some of the ultrastructural changes observed overlap with those induced by prolonged starvation, whereas others can be useful biomarkers of heavy metal toxicity. This study has confirmed that in terrestrial isopods, the accumulation of the different metals occurs in a species-specific manner; therefore ecological monitoring and assessment studies should consider each species individually. The research has confirmed that in the terrestrial isopods the accumulation of the different metals occurs in a species-specific way; therefore each species should first be evaluated in view of its employ in biomonitoring programs. PMID:25279851

  2. Contrasting Phylogeography of Sandy vs. Rocky Supralittoral Isopods in the Megadiverse and Geologically Dynamic Gulf of California and Adjacent Areas

    PubMed Central

    Hurtado, Luis A.; Lee, Eun Jung; Mateos, Mariana

    2013-01-01

    Phylogeographic studies of animals with low vagility and restricted to patchy habitats of the supralittoral zone, can uncover unknown diversity and shed light on processes that shaped evolution along a continent’s edge. The Pacific coast between southern California and central Mexico, including the megadiverse Gulf of California, offers a remarkable setting to study biological diversification in the supralittoral. A complex geological history coupled with cyclical fluctuations in temperature and sea level provided ample opportunities for diversification of supralittoral organisms. Indeed, a previous phylogeographic study of Ligia, a supralittoral isopod that has limited dispersal abilities and is restricted to rocky patches, revealed high levels of morphologically cryptic diversity. Herein, we examined phylogeographic patterns of Tylos, another supralittoral isopod with limited dispersal potential, but whose habitat (i.e., sandy shores) appears to be more extensive and connected than that of Ligia. We conducted Maximum Likelihood and Bayesian phylogenetic analyses on mitochondrial and nuclear DNA sequences. These analyses revealed multiple highly divergent lineages with discrete regional distributions, despite the recognition of a single valid species for this region. A traditional species-diagnostic morphological trait distinguished several of these lineages. The phylogeographic patterns of Tylos inside the Gulf of California show a deep and complex history. In contrast, patterns along the Pacific region between southern California and the Baja Peninsula indicate a recent range expansion, probably postglacial and related to changes in sea surface temperature (SST). In general, the phylogeographic patterns of Tylos differed from those of Ligia. Differences in the extension and connectivity of the habitats occupied by Tylos and Ligia may account for the different degrees of population isolation experienced by these two isopods and their contrasting phylogeographic patterns. Identification of divergent lineages of Tylos in the study area is important for conservation, as some populations are threatened by human activities. PMID:23844103

  3. Facilitation and predation structure a grassland detrital food web: the responses of soil nematodes to isopod processing of litter.

    PubMed

    Bastow, Justin L

    2011-09-01

    1. Detritus can support successive consumers, whose interactions may be structured by changes in the condition of their shared resource. One model of such species interactions is a processing chain, in which consumers feeding on the resource in a less processed state change the resource condition for subsequent consumers. 2. In a series of experiments, the hypothesis was tested that a common detritivore, the terrestrial isopod Porcellio scaber, affects soil nematodes through the processing of plant litter. Different detrital resources were added to soil from a California coastal prairie in order to simulate litter processing by the detritivore. Treatments that included only whole grass litter corresponded to detrital food webs lacking detritivores, while treatments that included mixtures of P. scaber faeces and grass litter corresponded to different densities or feeding rates of P. scaber. 3. Simulated litter processing by P. scaber increased the abundance of bacterivorous nematodes by between 32% and 202% after 24-44 days in laboratory experiments, but had no effect on fungivorous or predaceous nematodes. 4. In a subsequent field experiment, however, fungivorous nematodes were suppressed by isopod litter processing while bacterivores showed no response. Instead, P. scaber processing of litter increased the abundance of predaceous nematodes in the field experiment by 176%. 5. When simulated litter processing of litter was crossed in laboratory experiments with predaceous nematode addition (comparable to the response of predators in the field experiment), the abundance of bacterivores was increased by isopod processing of litter (by an average of 122%), but suppressed by elevated densities of predaceous nematodes (by an average of 41%). 6. This suggests that litter processing by P. scaber facilitates the bacterial channel of the soil food web, but that predaceous nematodes suppress the response of bacterivores in the field. Processing chain interactions may, therefore, be important in understanding the relative importance of bacterial and fungal channels in the soil food web, while top-down effects of predators determine the resulting changes in population abundance and biomass. PMID:21561453

  4. Hyperparasitism of the cryptoniscid isopod Liriopsis pygmaea on the lithodid Paralomis granulosa from the Beagle Channel, Argentina.

    PubMed

    Lovrich, Gustavo A; Roccatagliata, Daniel; Peresan, Laura

    2004-01-28

    A total of 29,570 false king crab Paralomis granulosa were sampled from the Beagle Channel (54 degrees 51'S, 68 degrees 12'W), Tierra del Fuego, Argentina, between July 1996 and August 1998. Crab size varied from 6.8 to 111.2 mm carapace length (CL). A few crabs parasitized by the rhizocephalan Briarosaccus callosus were found; prevalences of externae (the rhizocephalan reproductive body) and scars (the mark left on the host after the death of the parasite) were 0.28 and 0.16%, respectively. Of 85 externae examined, 55 were non-ovigerous and 30 ovigerous. The cryptoniscid isopod Liriopsis pygmaea infested 36.5% of the B. callosus examined. The most abundant stage was the cryptonicus larva, accounting for 208 of the 238 L. pygmaea recovered. Cryptonisci showed a highly aggregated distribution. A total of 92.7% of cryptonicsci were recovered inside empty externae, suggesting that the latter were attractive to cryptonisci. Early subadult females of L. pygmaea were rare; only 3 individuals occurred inside 1 ovigerous externa. Eight late subadult and 18 adult females were found on 3 and 7 non-ovigerous externae, respectively; in addition, 1 aberrant late subadult was found on 1 ovigerous externa. In the Beagle Channel, the population of P. granulosa harbours 3 different parasites: the bopyrid isopod Pseudione tuberculata, which reaches highest prevalence at 10 to 20 mm CL, the rhizocephalan B. callosus, with highest prevalence at 20 to 40 mm CL, and the cryptoniscid isopod L. pygmaea, which mainly infests rhizocephalan on crabs >40 mm CL. PMID:15038454

  5. Quantifying Beach Response to Episodic Large Wave Events, a Predictive Empirical Model, Ocean Beach, San Francisco, CA

    NASA Astrophysics Data System (ADS)

    Hansen, J. E.; Barnard, P. L.

    2006-12-01

    Predicting beach response on an event scale is extremely difficult due to highly variable spatial and temporal conditions, lack of data on antecedent beach morphology, generic model shortcomings, and uncertainty of local forcing parameters. Each beach system is unique and classical beach erosion models may not be applicable to many high-energy beaches, especially those receiving large long-period waves. Therefore, developing an empirical model is the best way to predict future beach response at a given site. Based on 12 closely spaced (temporally) GPS topographic surveys during the winter of 2005-2006 at Ocean Beach, in San Francisco, California, we have developed a predictive empirical model that relates sub-aerial beach response to observed wave height, period, and direction. The model will provide important information to coastal managers, who will be able to better predict and mitigate possible loss from a forecasted wave event. Ocean Beach, located immediately south of the Golden Gate in San Francisco, is a high-energy, intermediate- slope beach that is exposed to waves generated in both the North and South Pacific. Winter breaking wave heights frequently reach 4 m and can exceed 7 m, with periods sometimes greater than 20 s. Our observations demonstrate that large seasonal variations in the sub-aerial beach profile are likely forced by several single large wave events. These events have led to the partial destruction of a recreational parking lot at the south end of the beach where an erosion hot spot is currently located, and continued erosion will threaten other parts of public infrastructure. This study, in combination with other ongoing research at Ocean Beach, will provide valuable insight that will not only aid local personnel in their management decisions but also contribute to a better understanding of sediment transport at high-energy beaches.

  6. Relationships Between Sand and Water Quality at Recreational Beaches

    PubMed Central

    Phillips, Matthew C.; Solo-Gabriele, Helena M.; Piggot, Alan M.; Klaus, James S.; Zhang, Yifan

    2011-01-01

    Enterococci are used to assess the risk of negative human health impacts from recreational waters. Studies have shown sustained populations of enterococci within sediments of beaches but comprehensive surveys of multiple tidal zones on beaches in a regional area and their relationship to beach management decisions are limited. We sampled three tidal zones on eight South Florida beaches in Miami-Dade and Broward counties and found that enterococci were ubiquitous within South Florida beach sands although their levels varied greatly both among the beaches and between the supratidal, intertidal and subtidal zones. The supratidal sands consistently had significantly higher (p<0.003) levels of enterococci (average 40 CFU/g dry sand) than the other two zones. Levels of enterococci within the subtidal sand correlated with the average level of enterococci in the water (CFU/100mL) for the season during which samples were collected (rs= 0.73). The average sand enterococci content over all the zones on each beach correlated with the average water enterococci levels of the year prior to sand samplings (rs=0.64) as well as the average water enterococci levels for the month after sand samplings (rs=0.54). Results indicate a connection between levels of enterococci in beach water and sands throughout South Florida’s beaches and suggest that the sands are one of the predominant reservoirs of enterococci impacting beach water quality. As a result, beaches with lower levels of enterococci in the sand had fewer exceedences relative to beaches with higher levels of sand enterococci. More research should focus on evaluating beach sand quality as a means to predict and regulate marine recreational water quality. PMID:22071324

  7. Relationships between sand and water quality at recreational beaches.

    PubMed

    Phillips, Matthew C; Solo-Gabriele, Helena M; Piggot, Alan M; Klaus, James S; Zhang, Yifan

    2011-12-15

    Enterococci are used to assess the risk of negative human health impacts from recreational waters. Studies have shown sustained populations of enterococci within sediments of beaches but comprehensive surveys of multiple tidal zones on beaches in a regional area and their relationship to beach management decisions are limited. We sampled three tidal zones on eight South Florida beaches in Miami-Dade and Broward counties and found that enterococci were ubiquitous within South Florida beach sands although their levels varied greatly both among the beaches and between the supratidal, intertidal and subtidal zones. The supratidal sands consistently had significantly higher (p < 0.003) levels of enterococci (average 40 CFU/g dry sand) than the other two zones. Levels of enterococci within the subtidal sand correlated with the average level of enterococci in the water (CFU/100mL) for the season during which samples were collected (r(s) = 0.73). The average sand enterococci content over all the zones on each beach correlated with the average water enterococci levels of the year prior to sand samplings (r(s) = 0.64) as well as the average water enterococci levels for the month after sand samplings (r(s) = 0.54). Results indicate a connection between levels of enterococci in beach water and sands throughout South Florida's beaches and suggest that the sands are one of the predominant reservoirs of enterococci impacting beach water quality. As a result, beaches with lower levels of enterococci in the sand had fewer exceedences relative to beaches with higher levels of sand enterococci. More research should focus on evaluating beach sand quality as a means to predict and regulate marine recreational water quality. PMID:22071324

  8. Integrated protecting plan for beach erosion. A case study in Plaka beach, E. Crete, Greece

    NASA Astrophysics Data System (ADS)

    Petrakis, Stelios; Alexandrakis, George; Kozyrakis, George; Hatziyanni, Eleni; Kampanis, Nikolaos

    2015-04-01

    Coastal zones are among the most active areas on Earth, being subjected to extreme wind / wave conditions, thus vulnerable to erosion. In Greece and Crete in particular, beach zones are extremely important for the welfare of the inhabitants, since, apart for the important biological and archaeological value of the beach zones, the socio-economic value is critical since a great number of human activities are concentrated in such areas (touristic facilities, fishing harbors etc.). The present study investigates the erosional procedures observed in Plaka beach, E. Crete, Greece, a highly touristic developed area with great archaeological interest and proposes a cost-effective solution. The factors taken into consideration for the proposed solution in reducing the erosion of the beach were the study of the climatological, geological and geomorphological regime of the area, the recent (~70 years) shifting of the coastline through the study of topographic maps, aerial photographs and satellite images, the creation of detailed bathymetric and seabed classification maps of the area and finally, a risk analysis in terms of erosional phenomena. On the basis of the above, it is concluded that the area under investigation is subjected to an erosional rate of about 1 m/10 years and the total land-loss for the past 70 years is about 4600 m2. Through the simulation of the wave regime we studied 3 possible scenarios, the "do-nothing" scenario, the construction of a detached submerged breakwater at the depth of 3 meters and, finally, the armoring of the existing beach-wall through the placement of appropriate size and material boulders, forming an artificial slope for the reducing of the wave breaking energy and a small scale nourishment plan. As a result, through the modeling of the above, the most appropriate and cost-effective solution was found to be the third, armoring of the existing coastal wall and nourishment of the beach periodically, thus the further undermining of the beach will be reduced and part of the beach can be replaced, and providing aesthetic and economic value to the beach in order to maintain the coastal protection programme. Acknowledgements This work was performed in the framework of the PEFYKA project within the KRIPIS Αction of the GSRT. The project is funded by Greece and the European Regional Development Fund of the European Union under the NSRF and the O.P. Competitiveness and Entrepreneurship. It has also been supported by the "Estimation of the vunlerability of coastal areas to climatic change and sea level rise. Pilot study in Crete isl. Programme for the promotion of the exchange and scientific cooperation between Greece and Germany" programme IKYDA2013.

  9. Measurement of natural radioactivity in beach sands from Rizhao bathing beach, China.

    PubMed

    Lu, Xinwei; Zhang, Xiaolan

    2008-01-01

    The natural radioactivity of (226)Ra, (232)Th and (40)K was determined for beach sand samples collected from Rizhao bathing beach, China, using gamma ray spectrometry. The measured activity in beach sand ranges from 7.6 to 17.2, 7.8 to 25.1 and 883.4 to 1313.6 Bq kg(-1) for (226)Ra, (232)Th and (40)K with mean values of 12.0, 15.2 and 1079.2 Bq kg(-1), respectively. The activity concentrations of (226)Ra and (232)Th in beach sands are lower, while (40)K is higher than the world average. The radium equivalent activity in all beach sand samples is lower than the safe limit set in the OECD report (370 Bq kg(-1)). The values of the external hazard index are less than unity. The mean outdoor air absorbed dose rate is 59.8 nGy h(-1) and the corresponding outdoor effective dose rate is 0.073 mSv y(-1). PMID:18325933

  10. A Transcriptomic Analysis of Cave, Surface, and Hybrid Isopod Crustaceans of the Species Asellus aquaticus.

    PubMed

    Stahl, Bethany A; Gross, Joshua B; Speiser, Daniel I; Oakley, Todd H; Patel, Nipam H; Gould, Douglas B; Protas, Meredith E

    2015-01-01

    Cave animals, compared to surface-dwelling relatives, tend to have reduced eyes and pigment, longer appendages, and enhanced mechanosensory structures. Pressing questions include how certain cave-related traits are gained and lost, and if they originate through the same or different genetic programs in independent lineages. An excellent system for exploring these questions is the isopod, Asellus aquaticus. This species includes multiple cave and surface populations that have numerous morphological differences between them. A key feature is that hybrids between cave and surface individuals are viable, which enables genetic crosses and linkage analyses. Here, we advance this system by analyzing single animal transcriptomes of Asellus aquaticus. We use high throughput sequencing of non-normalized cDNA derived from the head of a surface-dwelling male, the head of a cave-dwelling male, the head of a hybrid male (produced by crossing a surface individual with a cave individual), and a pooled sample of surface embryos and hatchlings. Assembling reads from surface and cave head RNA pools yielded an integrated transcriptome comprised of 23,984 contigs. Using this integrated assembly as a reference transcriptome, we aligned reads from surface-, cave- and hybrid- head tissue and pooled surface embryos and hatchlings. Our approach identified 742 SNPs and placed four new candidate genes to an existing linkage map for A. aquaticus. In addition, we examined SNPs for allele-specific expression differences in the hybrid individual. All of these resources will facilitate identification of genes and associated changes responsible for cave adaptation in A. aquaticus and, in concert with analyses of other species, will inform our understanding of the evolutionary processes accompanying adaptation to the subterranean environment. PMID:26462237

  11. Histological studies on the marsupium of two terrestrial isopods (Crustacea, Isopoda, Oniscidea).

    PubMed

    Csonka, Diána; Halasy, Katalin; Hornung, Elisabeth

    2015-01-01

    The marsupium, a brood pouch in peracarid crustaceans (Crustacea, Malacostraca) has evolved in terrestrial environment for providing nutrition and optimal conditions for embryogenesis. In the present study we give details on the histology and ultrastructure of its constituting elements such as oostegites and cotyledons. Marsupia of two different eco-morphological types of woodlice, namely the non-conglobating species Trachelipusrathkii Brandt, 1833 and the conglobating species Cylisticusconvexus De Geer, 1778 were investigated. Light microscopic (LM) studies showed some differences in the main structure of the two species' brood pouch: in Trachelipusrathkii, a 'clinger' type woodlice, the oostegites bend outwards during brood incubation as growing offspring require more space, while in Cylisticusconvexus, a 'roller' type isopod, the sternites arch into the body cavity to ensure space for developing offspring and still allowing conglobation of the gravid females. The quantitative analysis of the oostegites' cuticle proved that the outer part is about 2.5 - 3 times thicker compared to the inner part in both species. Electron microscopic (TEM) examinations show only small histological differences in the oostegites and cotyledon structure of the two species. Cellular elements and moderately electron dense fleecy precipitate are found in the hemolymph space between the two cuticles of oostegites. The cells contain PAS positive polysaccharide areas. TEM studies revealed some differences in the cotyledon ultrastructure of the two species. Cotyledons of Trachelipusrathkii consist of cells with cristate mitochondria and granular endoplasmic reticulum with cisterns. Cotyledons of Cylisticusconvexus consist of cells with densely cristate mitochondria and ribosomes attached to vesicular membrane structures. In both species cells with electron dense bodies were observed. We conclude that - besides the differences in marsupial shapes - the fine structure of the oostegites and cotyledons is hardly affected by the eco-morphological type, specifically the conglobating or non-conglobating character of the studied species. PMID:26261442

  12. Global diversity of fish parasitic isopod crustaceans of the family Cymothoidae.

    PubMed

    Smit, Nico J; Bruce, Niel L; Hadfield, Kerry A

    2014-08-01

    Of the 95 known families of Isopoda only a few are parasitic namely, Bopyridae, Cryptoniscidae, Cymothoidae, Dajidae, Entoniscidae, Gnathiidae and Tridentellidae. Representatives from the family Cymothoidae are obligate parasites of both marine and freshwater fishes and there are currently 40 recognised cymothoid genera worldwide. These isopods are large (>6 mm) parasites, thus easy to observe and collect, yet many aspects of their biodiversity and biology are still unknown. They are widely distributed around the world and occur in many different habitats, but mostly in shallow waters in tropical or subtropical areas. A number of adaptations to an obligatory parasitic existence have been observed, such as the body shape, which is influenced by the attachment site on the host. Cymothoids generally have a long, slender body tapering towards the ends and the efficient contour of the body offers minimum resistance to the water flow and can withstand the forces of this particular habitat. Other adaptations to this lifestyle include small sensory antennae and eyes; a very heavily thickened and calcified cuticle for protection; and sharply curved hooks on the ends of the pereopods which allows these parasites to attach to the host. Most cymothoids are highly site and host specific. Some of these parasitic cymothoids have been reported to parasitise the same host fish species for over 100 years, showing this species specificity. The site of attachment on the host (gills, mouth, external surfaces or inside the host flesh) can also be genus or species specific. This paper aims to provide a summary of our current knowledge of cymothoid biodiversity and will highlight their history of discovery, morphology, relationships and classification, taxonomic diversity and ecology. PMID:25180163

  13. Microscopical and functional aspects of calcium-transport and deposition in terrestrial isopods.

    PubMed

    Ziegler, Andreas; Fabritius, Helge; Hagedorn, Monica

    2005-01-01

    Terrestrial isopods (Crustacea) are excellent model organisms to study epithelial calcium-transport and the regulation of biomineralization processes. They molt frequently and resorb cuticular CaCO(3) before the molt to prevent excessive loss of Ca(2+) ions when the old cuticle is shed. The resorbed mineral is stored in CaCO(3) deposits within the ecdysial gap of the first four anterior sternites. After the molt, the deposits are quickly resorbed to mineralise the posterior part of the new cuticle. The deposits contain numerous small spherules composed of an organic matrix and amorphous CaCO(3), which has a high solubility and, therefore, facilitates quick mobilization of Ca(2+) and HCO(3)(-) ions. During the formation and resorption of the deposits large amounts of Ca(2+), HCO(3)(-) and H(+) are transported across the anterior sternal epithelial cells. Within the last years, various light and electron microscopical techniques have been used to characterize the CaCO(3) deposits and the cellular mechanisms involved in biomineralization. The work on the CaCO(3) deposits includes studies on the ultrastructure of the deposits, the sequence of events during deposit formation and dissolution, and the mineral composition of the sternal deposits. The differentiation of the anterior sternal epithelial cells and the mechanisms of epithelial ion transport required for the mineralization and demineralisation of the deposits was studied using various analytical light and electron microscopical techniques including polarized light microscopy, immunocytochemistry, electron microprobe analysis, electron energy loss spectroscopy and electron spectroscopic imaging. Comparative analysis of deposit morphology and the differentiation of the sternal epithelia provide information on the evolution of CaCO(3) deposit formation in relation to the degree of adaptation to terrestrial environments. PMID:15629645

  14. Natatory-stage cymothoid isopods: description, molecular identification and evolution of attachment.

    PubMed

    Jones, Conor M; Miller, Terrence L; Grutter, Alexandra S; Cribb, Thomas H

    2008-03-01

    Cymothoid isopods are parasites that have a biphasic life cycle comprised of free-swimming micropredatory stages that eventually attach permanently to fishes, on which they change sex and morphology. Thus, matching free-swimming and permanently attached life-history stages is difficult. We attempted to identify natatory-stage cymothoids by seeking matches of partial 16S rRNA gene sequences from these stages and described adult cymothoids. Natatory cymothoids were collected from light traps at Lizard Island, Great Barrier Reef and adult females were collected from fishes from several sites along the east coast of Australia. A 488bp alignment of 16S mtDNA was compared for nine species of adult cymothoids and 10 natatory-stage morphotypes. Sequences from five natatory morphotypes were similar or identical to described specimens. Sequences identical to those of Anilocra nemipteri and Cymothoa indica were collected and these are considered definitive identifications. Sequences of three other morphotypes were highly similar (97.1-99.8% homologous) to described species; the differences may reflect a low level of sequencing error, intra-specific variation or the presence of complexes of species. Figures and descriptions are provided for identified and unidentified natatory cymothoids. The sequences were also used to explore the phylogenetic relationships of these taxa using minimum evolution, maximum parsimony, maximum likelihood and Bayesian inference analyses. Topologies from each of the four phylogenetic analyses did not differ significantly. Bayesian inference and maximum likelihood methods produced identical topologies with the highest resolution. These analyses showed that some morphological characters (pereopods and uropods) of natatory stages were distributed consistently on these molecular phylogenies, raising the possibility of identifying some natatory stages to genus. Our results suggest that ancestral cymothoids attached in the buccal or gill cavity and that external attachment, as seen in Anilocra and Renocila is a derived condition that has arisen more than once. PMID:17880981

  15. Graded neuromuscular transmission in the heart of the isopod crustacean Ligia exotica.

    PubMed

    Sakurai, A; Yamagishi, H

    2000-05-01

    We present several lines of evidence for the occurrence of graded synaptic transmission in addition to impulse-mediated transmission at the neuromuscular junction between cardiac ganglion (CG) neurones and the myocardium in the isopod crustacean Ligia exotica. In the heart of adult Ligia exotica, the CG acts as a primary pacemaker for the heartbeat by generating periodic bursts of impulses and entrains the myogenicity of the myocardium via impulse-mediated excitatory junctional potentials. When impulse generation was blocked by tetrodotoxin (TTX; 50 nmol l(-)(1)), the CG neurones and the myocardium periodically exhibited synchronized slow depolarizing potentials. The association between the slow depolarizing potentials in the neurone and the myocardium was eliminated by application of Joro spider toxin (JSTX), a specific glutamate antagonist. When the CG neurone was made quiescent by a higher dose of TTX (1.0 micromol l(-)(1)), sinusoidal current injected into the CG neurone induced similar sinusoidal membrane potential responses in the myocardium. The sinusoidal muscle responses were eliminated by application of either JSTX or low-Ca(2+) saline. Under voltage-clamp conditions, the myocardium exhibited periodic inward current responses to sinusoidal current stimuli applied to the CG neurone. The reversal potential for the current response of the myocardium was similar to that of the impulse-mediated excitatory junctional current (EJC). Extracellular macropatch recordings of EJCs made at the neuromuscular junctional site revealed the spontaneous appearance of miniature EJCs asynchronous with the CG spikes in addition to large spike-evoked EJCs. The miniature EJCs were present in saline containing TTX, and their frequency was strongly affected by the slow membrane potential change in the CG neurone. These results suggest that the CG neurones drive the myocardium by graded neuromuscular transmission in addition to impulse-mediated transmission in the heart of Ligia exotica. PMID:10751160

  16. Tension sensitivity of the heart pacemaker neurons in the isopod crustacean Ligia pallasii.

    PubMed

    Sakurai, Akira; Wilkens, Jerrel L

    2003-01-01

    In the crustacean neurogenic heart, the cardiac ganglion (CG) acts as a peripherally located central pattern generator (CPG) by producing rhythmic motor output that initiates the heartbeat. In the isopod Ligia, the CG consists of six electrically coupled neurons that all function both as endogenous oscillators and as glutamatergic motoneurons innervating heart muscle. In the present study, we present several lines of evidence to suggest that the CG neurons are sensitive to passive stretch and active tension of the heart muscle. Stretching the heart wall caused a sustained decrease in the burst frequency of the CG neuron. Releasing from the stretch caused a rebound increase in burst frequency above the control rate. A brief stretch (200-300 ms duration) caused either phase advance or phase delay of the following CG bursts, depending on the timing at which the stretch was applied. Repeated brief stretches could entrain the CG bursts to either higher or lower frequencies than the free-run burst frequency. Intracellular recording from one of the CG neurons revealed that it exhibited hyperpolarization during the stretch. The stretch-induced hyperpolarization was followed by a burst discharge upon release from the stretch. With increased stretch amplitude, the amplitude of hyperpolarizing response increased and the timing of the following burst was advanced. When the myogenic activity of the heart muscle was pharmacologically isolated from the ganglionic drive by applying a glutamatergic antagonist, Joro spider toxin (JSTX), the spontaneous muscle contraction caused a hyperpolarizing deflection in the CG neuron. Under specific conditions made by JSTX and tetrodotoxin, the CG burst became entrained to the myogenic rhythm. These results suggest that the Ligia CG neurons have tension sensitivity in addition to their pacemaker and motoneuronal functions. Such multifunctional neurons may form a single neuron reflex arc inside the heart. PMID:12456701

  17. Histological studies on the marsupium of two terrestrial isopods (Crustacea, Isopoda, Oniscidea)

    PubMed Central

    Csonka, Diána; Halasy, Katalin; Hornung, Elisabeth

    2015-01-01

    Abstract The marsupium, a brood pouch in peracarid crustaceans (Crustacea, Malacostraca) has evolved in terrestrial environment for providing nutrition and optimal conditions for embryogenesis. In the present study we give details on the histology and ultrastructure of its constituting elements such as oostegites and cotyledons. Marsupia of two different eco-morphological types of woodlice, namely the non-conglobating species Trachelipus rathkii Brandt, 1833 and the conglobating species Cylisticus convexus De Geer, 1778 were investigated. Light microscopic (LM) studies showed some differences in the main structure of the two species’ brood pouch: in Trachelipus rathkii, a ‘clinger’ type woodlice, the oostegites bend outwards during brood incubation as growing offspring require more space, while in Cylisticus convexus, a ‘roller’ type isopod, the sternites arch into the body cavity to ensure space for developing offspring and still allowing conglobation of the gravid females. The quantitative analysis of the oostegites’ cuticle proved that the outer part is about 2.5 - 3 times thicker compared to the inner part in both species. Electron microscopic (TEM) examinations show only small histological differences in the oostegites and cotyledon structure of the two species. Cellular elements and moderately electron dense fleecy precipitate are found in the hemolymph space between the two cuticles of oostegites. The cells contain PAS positive polysaccharide areas. TEM studies revealed some differences in the cotyledon ultrastructure of the two species. Cotyledons of Trachelipus rathkii consist of cells with cristate mitochondria and granular endoplasmic reticulum with cisterns. Cotyledons of Cylisticus convexus consist of cells with densely cristate mitochondria and ribosomes attached to vesicular membrane structures. In both species cells with electron dense bodies were observed. We conclude that - besides the differences in marsupial shapes - the fine structure of the oostegites and cotyledons is hardly affected by the eco-morphological type, specifically the conglobating or non-conglobating character of the studied species. PMID:26261442

  18. Host tissues as microhabitats for Wolbachia and quantitative insights into the bacterial community in terrestrial isopods.

    PubMed

    Dittmer, J; Beltran-Bech, S; Lesobre, J; Raimond, M; Johnson, M; Bouchon, D

    2014-05-01

    Animal-bacterial symbioses are highly dynamic in terms of multipartite interactions, both between the host and its symbionts as well as between the different bacteria constituting the symbiotic community. These interactions will be reflected by the titres of the individual bacterial taxa, for example via host regulation of bacterial loads or competition for resources between symbionts. Moreover, different host tissues represent heterogeneous microhabitats for bacteria, meaning that host-associated bacteria might establish tissue-specific bacterial communities. Wolbachia are widespread endosymbiotic bacteria, infecting a large number of arthropods and filarial nematodes. However, relatively little is known regarding direct interactions between Wolbachia and other bacteria. This study represents the first quantitative investigation of tissue-specific Wolbachia-microbiota interactions in the terrestrial isopod Armadillidium vulgare. To this end, we obtained a more complete picture of the Wolbachia distribution patterns across all major host tissues, integrating all three feminizing Wolbachia strains (wVulM, wVulC, wVulP) identified to date in this host. Interestingly, the different Wolbachia strains exhibited strain-specific tissue distribution patterns, with wVulM reaching lower titres in most tissues. These patterns were consistent across different host genetic backgrounds and might reflect different co-evolutionary histories between the Wolbachia strains and A. vulgare. Moreover, Wolbachia-infected females carried higher total bacterial loads in several, but not all, tissues, irrespective of the Wolbachia strain. Taken together, this quantitative approach indicates that Wolbachia is part of a potentially more diverse bacterial community, as exemplified by the presence of highly abundant bacterial taxa in the midgut caeca of several A. vulgare populations. PMID:24750488

  19. Testis follicles ultrastructure of three species of terrestrial isopods (Crustacea, Isopoda Oniscidea).

    PubMed

    Mazzei, V; Longo, G; Brundo, M V

    2015-10-01

    The aim of the research, carried out on three species of terrestrial isopods - Armadillidium granulatum, Halophiloscia hirsuta and Trichoniscus alexandrae - is to bring a first consistent contribution to the knowledge of the ultrastructural organization of the testis follicles. The testis follicles are seat of a remarkable dynamic activity of their cell components (somatic cells and germ cells) that results in a continuous variation, related to the trend of spermatogenesis, of their morphology, organization and of the relationships between the two cell populations. The somatic cells, known in literature as follicular cells, nurse cells or Sertoli cells, are arranged at the periphery of the follicle to form an epithelial layer of variable thickness resting on a thin basal lamina in turn surrounded by a discontinuous network of muscle cells. In A. granulatum and H. hirsuta, two types of Sertoli cells are present: a first type, the nurse cells, envelop the spermatids in cavities within their cytoplasm and through their secretion activity play a fundamental role in the formation of the spermatophores; moreover, they phagocytizes the residual cytoplasm of spermatids. A second type of Sertoli cells shows features that leave clearly identify its supporting role to the spermatophores in formation. In T. alexandrae, instead, only one type of Sertoli cells, the nurse cell, is present, whose features are widely superimposable to those observed in the other two species. Moreover, two septa of Sertoli cells depart from the periphery of the testis follicle to constitute an articulated compartmentalization of the follicle itself, probably targeted to realize at its inside a series of microenvironments functionally diversified in order to meets the needs of the different stages of the spermatogenic cycle. PMID:26276088

  20. A Transcriptomic Analysis of Cave, Surface, and Hybrid Isopod Crustaceans of the Species Asellus aquaticus

    PubMed Central

    Stahl, Bethany A.; Gross, Joshua B.; Speiser, Daniel I.; Oakley, Todd H.; Patel, Nipam H.; Gould, Douglas B.; Protas, Meredith E.

    2015-01-01

    Cave animals, compared to surface-dwelling relatives, tend to have reduced eyes and pigment, longer appendages, and enhanced mechanosensory structures. Pressing questions include how certain cave-related traits are gained and lost, and if they originate through the same or different genetic programs in independent lineages. An excellent system for exploring these questions is the isopod, Asellus aquaticus. This species includes multiple cave and surface populations that have numerous morphological differences between them. A key feature is that hybrids between cave and surface individuals are viable, which enables genetic crosses and linkage analyses. Here, we advance this system by analyzing single animal transcriptomes of Asellus aquaticus. We use high throughput sequencing of non-normalized cDNA derived from the head of a surface-dwelling male, the head of a cave-dwelling male, the head of a hybrid male (produced by crossing a surface individual with a cave individual), and a pooled sample of surface embryos and hatchlings. Assembling reads from surface and cave head RNA pools yielded an integrated transcriptome comprised of 23,984 contigs. Using this integrated assembly as a reference transcriptome, we aligned reads from surface-, cave- and hybrid- head tissue and pooled surface embryos and hatchlings. Our approach identified 742 SNPs and placed four new candidate genes to an existing linkage map for A. aquaticus. In addition, we examined SNPs for allele-specific expression differences in the hybrid individual. All of these resources will facilitate identification of genes and associated changes responsible for cave adaptation in A. aquaticus and, in concert with analyses of other species, will inform our understanding of the evolutionary processes accompanying adaptation to the subterranean environment. PMID:26462237

  1. Patterns of the Non-Indigenous Isopod Cirolana harfordi in Sydney Harbour

    PubMed Central

    Bugnot, Ana B.; Coleman, Ross A.; Figueira, Will F.; Marzinelli, Ezequiel M.

    2014-01-01

    Biological introductions can alter the ecology of local assemblages and are an important driver of global environmental change. The first step towards understanding the impact of a non-indigenous species is to study its distribution and associations in the invaded area. In Sydney Harbour, the non-indigenous isopod Cirolana harfordi has been reported in densities up to 0.5 individuals per cm2 in mussel-beds. Abundances of this species have, however, been largely overlooked in other key habitats. The first aim of this study was to evaluate the abundances and distribution of C. harfordi across different habitats representative of Sydney Harbour. Results showed that C. harfordi occurred in oyster and mussel-beds, being particularly abundant in oyster-beds. We also aimed to determine the role of C. harfordi as a predator, scavenger and detritus feeder by investigating the relationships between densities of C. harfordi and (i) the structure of the resident assemblages, and (ii) deposited organic matter in oyster-beds. Densities of C. harfordi were not related to the structure of the assemblages, nor amounts of deposited organic matter. These findings suggested little or no ecological impacts of C. harfordi in oyster-beds. These relationships may, however, affect other variables such as growth of individuals, or be disguised by high variability of assemblages among different locations. Future studies should, therefore, test the impacts of C. harfordi on the size of organisms in the assemblage and use manipulative experiments to control for spatial variation. This study is the first published work on the ecology of the invasion of C. harfordi and provides the starting-point for the study of the impacts of this species in Sydney Harbour. PMID:24466227

  2. Global diversity of fish parasitic isopod crustaceans of the family Cymothoidae

    PubMed Central

    Smit, Nico J.; Bruce, Niel L.; Hadfield, Kerry A.

    2014-01-01

    Of the 95 known families of Isopoda only a few are parasitic namely, Bopyridae, Cryptoniscidae, Cymothoidae, Dajidae, Entoniscidae, Gnathiidae and Tridentellidae. Representatives from the family Cymothoidae are obligate parasites of both marine and freshwater fishes and there are currently 40 recognised cymothoid genera worldwide. These isopods are large (>6 mm) parasites, thus easy to observe and collect, yet many aspects of their biodiversity and biology are still unknown. They are widely distributed around the world and occur in many different habitats, but mostly in shallow waters in tropical or subtropical areas. A number of adaptations to an obligatory parasitic existence have been observed, such as the body shape, which is influenced by the attachment site on the host. Cymothoids generally have a long, slender body tapering towards the ends and the efficient contour of the body offers minimum resistance to the water flow and can withstand the forces of this particular habitat. Other adaptations to this lifestyle include small sensory antennae and eyes; a very heavily thickened and calcified cuticle for protection; and sharply curved hooks on the ends of the pereopods which allows these parasites to attach to the host. Most cymothoids are highly site and host specific. Some of these parasitic cymothoids have been reported to parasitise the same host fish species for over 100 years, showing this species specificity. The site of attachment on the host (gills, mouth, external surfaces or inside the host flesh) can also be genus or species specific. This paper aims to provide a summary of our current knowledge of cymothoid biodiversity and will highlight their history of discovery, morphology, relationships and classification, taxonomic diversity and ecology. PMID:25180163

  3. Patterns of the non-indigenous isopod Cirolana harfordi in Sydney Harbour.

    PubMed

    Bugnot, Ana B; Coleman, Ross A; Figueira, Will F; Marzinelli, Ezequiel M

    2014-01-01

    Biological introductions can alter the ecology of local assemblages and are an important driver of global environmental change. The first step towards understanding the impact of a non-indigenous species is to study its distribution and associations in the invaded area. In Sydney Harbour, the non-indigenous isopod Cirolana harfordi has been reported in densities up to 0.5 individuals per cm(2) in mussel-beds. Abundances of this species have, however, been largely overlooked in other key habitats. The first aim of this study was to evaluate the abundances and distribution of C. harfordi across different habitats representative of Sydney Harbour. Results showed that C. harfordi occurred in oyster and mussel-beds, being particularly abundant in oyster-beds. We also aimed to determine the role of C. harfordi as a predator, scavenger and detritus feeder by investigating the relationships between densities of C. harfordi and (i) the structure of the resident assemblages, and (ii) deposited organic matter in oyster-beds. Densities of C. harfordi were not related to the structure of the assemblages, nor amounts of deposited organic matter. These findings suggested little or no ecological impacts of C. harfordi in oyster-beds. These relationships may, however, affect other variables such as growth of individuals, or be disguised by high variability of assemblages among different locations. Future studies should, therefore, test the impacts of C. harfordi on the size of organisms in the assemblage and use manipulative experiments to control for spatial variation. This study is the first published work on the ecology of the invasion of C. harfordi and provides the starting-point for the study of the impacts of this species in Sydney Harbour. PMID:24466227

  4. Beaches and Dunes of Developed Coasts

    NASA Astrophysics Data System (ADS)

    Nordstrom, Karl F.

    2004-06-01

    This volume discusses the role of humans in transforming the coastal landscape. The book details the many ways beaches and dunes are eliminated, altered and replaced and the differences between natural landforms and the human artefacts that replace them. Emphasis is placed on the importance of retaining naturally functioning beaches and dunes in ways that achieve natural values while accommodating development and use. The issues dealt with in this book will be of interest to practising coastal engineers and research scientists, as well as to planners and managers of coastal resources at all levels of government. It will be of particular value to investigators planning for the future of coastal development under accelerated sea level rise. The book will also be useful as a reference text for graduate and advanced undergraduate courses in geography, geology, ecology and other disciplines dealing with the interaction between science, technology and society.

  5. Virginia Beach search and rescue experiment

    NASA Astrophysics Data System (ADS)

    Rais, Houra; Mansfield, Arthur W.; Huxtable, Barton D.; Chotoo, Kancham

    2000-08-01

    In May, 1998, the NASA Search and Rescue Mission conducted a SAR crash detection test in the swampy area south and west of Virginia Beach. A number of aircraft parts were hidden in the dense foliage. The radar used was the Navy P-3 with the ERIM XLC and UHF SAR, providing fine resolution imagery with full polarimetry and an IFSAR capability. This paper reports preliminary results of this test.

  6. Sand Beach Bacteria: Enumeration and Characterization

    PubMed Central

    Khiyama, H. M.; Makemson, J. C.

    1973-01-01

    Bacteria in the water-saturated sand of a relatively unpolluted sand beach were enumerated by direct microscope and viable counting. The number of interstitial bacteria was estimated to be a significant fraction of the total number of bacteria present. Three hundred sixty-two strains were isolated and submitted to cultural and biochemical tests. Fermentational abilities and the production of indole suggested that a significant number of these bacteria were symbiotically associated with resident metazoans. PMID:4356458

  7. Independent risk factors for beach-related injuries in children.

    PubMed

    Petronis, Kelli A; Welch, J Camille; Pruitt, Charles W

    2009-06-01

    This study was conducted in a resort area during the summer tourist season to identify independent risk factors for injuries to children in a beach environment. Surveys including demographics, environmental and beach conditions, group characteristics, and hypothesized risk factors were administered to 28 cases and 105 controls. The most common injuries were lacerations and puncture wounds, followed by musculoskeletal injuries. The following environmental factors were found to significantly increase the risk for pediatric beach-related injury: rough/choppy water, cloudy weather, greater than 3 children in the group, participation by the child in water safety classes, and use of beach equipment (including boogie boards, skim boards, and kayaks). Providers who care for children can use this information to educate parents about beach safety. Targeted interventions that address these risk factors may reduce injuries sustained by children in a beach environment. PMID:19164132

  8. The expression of one ankyrin pk2 allele of the WO prophage is correlated with the Wolbachia feminizing effect in isopods

    PubMed Central

    2012-01-01

    Background The maternally inherited ?-Proteobacteria Wolbachia pipientis is an obligate endosymbiont of nematodes and arthropods, in which they induce a variety of reproductive alterations, including Cytoplasmic Incompatibility (CI) and feminization. The genome of the feminizing wVulC Wolbachia strain harboured by the isopod Armadillidium vulgare has been sequenced and is now at the final assembly step. It contains an unusually high number of ankyrin motif-containing genes, two of which are homologous to the phage-related pk1 and pk2 genes thought to contribute to the CI phenotype in Culex pipiens. These genes encode putative bacterial effectors mediating Wolbachia-host protein-protein interactions via their ankyrin motifs. Results To test whether these Wolbachia homologs are potentially involved in altering terrestrial isopod reproduction, we determined the distribution and expression of both pk1 and pk2 genes in the 3 Wolbachia strains that induce CI and in 5 inducing feminization of their isopod hosts. Aside from the genes being highly conserved, we found a substantial copy number variation among strains, and that is linked to prophage diversity. Transcriptional analyses revealed expression of one pk2 allele (pk2b2) only in the feminizing Wolbachia strains of isopods. Conclusions These results reveal the need to investigate the functions of Wolbachia ankyrin gene products, in particular those of Pk2, and their host targets with respect to host sex manipulation. PMID:22497736

  9. Deep down: Isopod biodiversity of the Kuril-Kamchatka abyssal area including a comparison with data of previous expeditions of the RV Vityaz

    NASA Astrophysics Data System (ADS)

    Elsner, Nikolaus O.; Malyutina, Marina V.; Golovan, Olga A.; Brenke, Nils; Riehl, Torben; Brandt, Angelika

    2015-01-01

    This study focusses on the isopod biodiversity in the abyssal area southeast of the Kuril-Kamchatka Trench. The KuramBio (Kuril-Kamchatka Biodiversity Studies) expedition in summer 2012 collected altogether 10,169 isopods from 21 C-EBS hauls at 12 stations, belonging to 19 families, 73 genera and 207 species from the depth range between 4830 and 5780 m. Munnopsidae and Desmosomatidae were the most abundant and species-rich families, Eurycope (Munnopsidae) and Macrostylis (Macrostylidae) the most abundant genera. An nMDS plot on the basis of the Cosine similarity index reveals no clear pattern and all hauls to be different from each other. We compared our data with 12 stations from the same depth range sampled by the Russian RV Vityaz about 50 years ago and were able to identify several species collected by the RV Vityaz. The identified isopod species belonged to the families Munnopsidae, Macrostylidae, Haploniscidae, Desmosomatidae, Ischnomesidae and Nannoniscidae. Of the 333 individuals collected by the RV Vityaz, Haploniscidae and Munnopsidae were the most abundant families. Desmosomatidae were only represented by <1% of the isopod individuals. However, the rarefaction curves of both the KuramBio and the Vityaz samples are not approaching an asymptote, indicating that even after repeated sampling just a part of the local fauna has been recorded so far.

  10. Draft Genome Sequence of “Candidatus Hepatoplasma crinochetorum” Ps, a Bacterial Symbiont in the Hepatopancreas of the Terrestrial Isopod Porcellio scaber

    PubMed Central

    Kostanjšek, Rok; Toenshoff, Elena R.; Schulz, Frederik; Schuster, Lisa; Domann, Daryl; Horn, Matthias

    2015-01-01

    “Candidatus Hepatoplasma crinochetorum” Ps is an extracellular symbiont residing in the hepatopancreas of the terrestrial isopod Porcellio scaber. Its genome is highly similar to that of the close relative “Ca. Hepatoplasma crinochetorum” Av from Armadillidium vulgare. However, instead of a clustered regularly interspaced short palindromic repeat (CRISPR)-Cas system, it encodes a type I restriction modification system. PMID:26272556

  11. Effects of soil and dietary exposures to Ag nanoparticles and AgNO? in the terrestrial isopod Porcellionides pruinosus.

    PubMed

    Tourinho, Paula S; van Gestel, Cornelis A M; Jurkschat, Kerstin; Soares, Amadeu M V M; Loureiro, Susana

    2015-10-01

    The effects of Ag-NPs and AgNO3 on the isopod Porcellionides pruinosus were determined upon soil and dietary exposures. Isopods avoided Ag in soil, with EC50 values of ?16.0 and 14.0 mg Ag/kg for Ag-NPs and AgNO3, respectively. Feeding inhibition tests in soil showed EC50s for effects on consumption ratio of 127 and 56.7 mg Ag/kg, respectively. Although similar EC50s for effects on biomass were observed for nanoparticulate and ionic Ag (114 and 120 mg Ag/kg dry soil, respectively), at higher concentrations greater biomass loss was found for AgNO3. Upon dietary exposure, AgNO3 was more toxic, with EC50 for effects on biomass change being >1500 and 233 mg Ag/kg for Ag-NPs and AgNO3, respectively. The difference in toxicity between Ag-NPs and AgNO3 could not be explained from Ag body concentrations. This suggests that the relation between toxicity and bioavailability of Ag-NPs differs from that of ionic Ag in soils. PMID:26071943

  12. Grazing preferences of marine isopods and amphipods on three prominent algal species of the Baltic Sea [rapid communication

    NASA Astrophysics Data System (ADS)

    Goecker, Margene E.; KÃ¥ll, Sara E.

    2003-12-01

    Preference tests were performed over a two-week period in September 2001 in which isopods ( Idotea baltica) and amphipods ( Gammarus oceanicus) were offered choices of three common species of algae from the Baltic Sea: Enteromorpha intestinalis, Cladophora spp., and Fucus vesiculosus. After a 48-hour starvation period, 20 individuals of each grazer species were placed in aquaria containing approximately 1.0 g of each algal species. Fifteen trials for each grazer species were run for 20 hours. We found that G. oceanicus ate significantly more Cladophora spp. and E. intestinalis than F. vesiculosus (p<0.001), with a preference order of: Cladophora spp.> E. intestinalis> F. vesiculosus. Similarly, I. baltica ate significantly more of both the filamentous green algae than F. vesiculosus (p<0.001), with a preference order of: E. intestinalis> Cladophora spp.> F. vesiculosus. Given the preference of isopods and amphipods for filamentous green algae, we might expect these algae to be maintained at low biomass levels. However, this is clearly not the case in the Baltic Sea. Nutrient enrichment (bottom-up effects) is the accepted dominant reason for the non-controlling impact of algal grazers, but other reasons may include cascading trophic effects resulting from the removal of large piscivorous fish (top-down effects).

  13. Multiple Conserved Heteroplasmic Sites in tRNA Genes in the Mitochondrial Genomes of Terrestrial Isopods (Oniscidea)

    PubMed Central

    Chandler, Christopher H.; Badawi, Myriam; Moumen, Bouziane; Grève, Pierre; Cordaux, Richard

    2015-01-01

    Mitochondrial genome structure and organization are relatively conserved among metazoans. However, in many isopods, especially the terrestrial isopods (Oniscidea), the mitochondrial genome consists of both ∼14-kb linear monomers and ∼28-kb circular dimers. This unusual organization is associated with an ancient and conserved constitutive heteroplasmic site. This heteroplasmy affects the anticodon of a tRNA gene, allowing this single locus to function as a “dual” tRNA gene for two different amino acids. Here, we further explore the evolution of these unusual mitochondrial genomes by assembling complete mitochondrial sequences for two additional Oniscidean species, Trachelipus rathkei and Cylisticus convexus. Strikingly, we find evidence of two additional heteroplasmic sites that also alter tRNA anticodons, creating additional dual tRNA genes, and that are conserved across both species. These results suggest that the unique linear/circular organization of isopods’ mitochondrial genomes may facilitate the evolution of stable mitochondrial heteroplasmies, and, conversely, once such heteroplasmies have evolved, they constrain the multimeric structure of the mitochondrial genome in these species. Finally, we outline some possible future research directions to identify the factors influencing mitochondrial genome evolution in this group. PMID:25911226

  14. Immunohistochemical study of androgenic gland hormone: localization in the male reproductive system and species specificity in the terrestrial isopods.

    PubMed

    Hasegawa, Yuriko; Okuno, Atsuro; Nagasawa, Hiromichi

    2002-02-01

    Androgenic gland hormone (AGH) is responsible for male sexual differentiation in crustaceans. AGH of the terrestrial isopod, Armadillidium vulgare, is a heterodimetric glycoprotein. To determine the distribution of AGH in the male reproductive system, an immunohistochemical study was carried out using antibodies raised against different components of the proAGH molecule of A. vulgare, for example, the whole molecule of recombinant proAGH expressed in Escherichia coli (E. coli-rAGH), the N-terminal nonapeptide of the B chain, and the N-terminal octapeptide of the A chain. The androgenic gland (AG) showed strong immunoreactivity to all three of these antibodies, while the testis, the seminal vesicle, and the vas deferens did not show immunostaining. To examine the species specificity of AGH, the male reproductive systems in nine species of Oniscidea were examined immunohistochemically with antibody raised against E. coli-rAGH. A positive reaction was observed in the AGs of species belonging to the Armadillidiidae, Porcellionidae, and Scyphacidae families. Immunoreactivity was strongest in A. vulgare and was stronger in Armadillidiidae than in Porcellionidae or in Scyphacidae. These results suggest that structural similarity of AGH may exist among some terrestrial isopods, although AGH seems to harbor a relatively high degree of species specificity. PMID:11884067

  15. Joint effects of three plant protection products to the terrestrial isopod Porcellionides pruinosus and the collembolan Folsomia candida.

    PubMed

    Santos, Miguel J G; Soares, Amadeu M V M; Loureiro, Susana

    2010-08-01

    The effects of simultaneous application of plant protection products are of concern since the uses of different products pose an additional risk to non-target soil organisms. The effects of binary combinations of dimethoate, glyphosate and spirodiclofen, an insecticide an herbicide and an acaricide, on the avoidance behaviour of the terrestrial isopod Porcellionides pruinosus and the reproductive effort of Folsomia candida were assessed using the two reference models of concentration addition (CA) and independent action (IA). Results of single exposure to the three pesticides indicated a clear dose related avoidance response of the isopods in the highest concentrations tested of the three as well as a strong decrease in collembolan adult survival and concomitant number of juveniles produced. In the combined experiments, antagonism was found in 7 out of the 12 combinations, four combinations followed the reference models, and only in one combination synergism was detected (lower doses of glyphosate and spirodiclofen applied to P. pruinosus). In conclusion, it seems that mixing and applying these products, at the recommended field application rate, does not lead to enhanced toxicity, hence limited risk is associated with the joint application of these pesticides. PMID:20579688

  16. Dune recovery after storm erosion on a high-energy beach: Vougot Beach, Brittany (France)

    NASA Astrophysics Data System (ADS)

    Suanez, Serge; Cariolet, Jean-Marie; Cancouët, Romain; Ardhuin, Fabrice; Delacourt, Christophe

    2012-02-01

    On 10th March 2008, the high energy storm Johanna hit the French Atlantic coast, generating severe dune erosion on Vougot Beach (Brittany, France). In this paper, the recovery of the dune of Vougot Beach is analysed through a survey of morphological changes and hydrodynamic conditions. Data collection focused on the period immediately following storm Johanna until July 2010, i.e. over two and a half years. Results showed that the dune retreated by a maximum of almost 6 m where storm surge and wave attack were the most energetic. Dune retreat led to the creation of accommodation space for the storage of sediment by widening and elevating space between the pre- and post-storm dune toe, and reducing impacts of the storm surge. Dune recovery started in the month following the storm event and is still ongoing. It is characterised by the construction of "secondary" embryo dunes, which recovered at an average rate of 4-4.5 cm per month, although average monthly volume changes varied from - 1 to 2 m 3.m - 1 . These embryo dunes accreted due to a large aeolian sand supply from the upper tidal beach to the existing foredune. These dune-construction processes were facilitated by growth of vegetation on low-profile embryo dunes promoting backshore accretion. After more than two years of survey, the sediment budget of the beach/dune system showed that more than 10,000 m 3 has been lost by the upper tidal beach. We suggest that seaward return currents generated during the storm of 10th March 2008 are responsible for offshore sediment transport. Reconstitution of the equilibrium beach profile following the storm event may therefore have generated cross-shore sediment redistribution inducing net erosion in the tidal zone.

  17. Shifts in the Microbial Community Composition of Gulf Coast Beaches Following Beach Oiling

    PubMed Central

    Newton, Ryan J.; Huse, Susan M.; Morrison, Hilary G.; Peake, Colin S.; Sogin, Mitchell L.; McLellan, Sandra L.

    2013-01-01

    Microorganisms associated with coastal sands serve as a natural biofilter, providing essential nutrient recycling in nearshore environments and acting to maintain coastal ecosystem health. Anthropogenic stressors often impact these ecosystems, but little is known about whether these disturbances can be identified through microbial community change. The blowout of the Macondo Prospect reservoir on April 20, 2010, which released oil hydrocarbons into the Gulf of Mexico, presented an opportunity to examine whether microbial community composition might provide a sensitive measure of ecosystem disturbance. Samples were collected on four occasions, beginning in mid-June, during initial beach oiling, until mid-November from surface sand and surf zone waters at seven beaches stretching from Bay St. Louis, MS to St. George Island, FL USA. Oil hydrocarbon measurements and NOAA shoreline assessments indicated little to no impact on the two most eastern beaches (controls). Sequence comparisons of bacterial ribosomal RNA gene hypervariable regions isolated from beach sands located to the east and west of Mobile Bay in Alabama demonstrated that regional drivers account for markedly different bacterial communities. Individual beaches had unique community signatures that persisted over time and exhibited spatial relationships, where community similarity decreased as horizontal distance between samples increased from one to hundreds of meters. In contrast, sequence analyses detected larger temporal and less spatial variation among the water samples. Superimposed upon these beach community distance and time relationships, was increased variability in bacterial community composition from oil hydrocarbon contaminated sands. The increased variability was observed among the core, resident, and transient community members, indicating the occurrence of community-wide impacts rather than solely an overprinting of oil hydrocarbon-degrading bacteria onto otherwise relatively stable sand population structures. Among sequences classified to genus, Alcanivorax, Alteromonas, Marinobacter, Winogradskyella, and Zeaxanthinibacter exhibited the largest relative abundance increases in oiled sands. PMID:24040219

  18. Shifts in the microbial community composition of Gulf Coast beaches following beach oiling.

    PubMed

    Newton, Ryan J; Huse, Susan M; Morrison, Hilary G; Peake, Colin S; Sogin, Mitchell L; McLellan, Sandra L

    2013-01-01

    Microorganisms associated with coastal sands serve as a natural biofilter, providing essential nutrient recycling in nearshore environments and acting to maintain coastal ecosystem health. Anthropogenic stressors often impact these ecosystems, but little is known about whether these disturbances can be identified through microbial community change. The blowout of the Macondo Prospect reservoir on April 20, 2010, which released oil hydrocarbons into the Gulf of Mexico, presented an opportunity to examine whether microbial community composition might provide a sensitive measure of ecosystem disturbance. Samples were collected on four occasions, beginning in mid-June, during initial beach oiling, until mid-November from surface sand and surf zone waters at seven beaches stretching from Bay St. Louis, MS to St. George Island, FL USA. Oil hydrocarbon measurements and NOAA shoreline assessments indicated little to no impact on the two most eastern beaches (controls). Sequence comparisons of bacterial ribosomal RNA gene hypervariable regions isolated from beach sands located to the east and west of Mobile Bay in Alabama demonstrated that regional drivers account for markedly different bacterial communities. Individual beaches had unique community signatures that persisted over time and exhibited spatial relationships, where community similarity decreased as horizontal distance between samples increased from one to hundreds of meters. In contrast, sequence analyses detected larger temporal and less spatial variation among the water samples. Superimposed upon these beach community distance and time relationships, was increased variability in bacterial community composition from oil hydrocarbon contaminated sands. The increased variability was observed among the core, resident, and transient community members, indicating the occurrence of community-wide impacts rather than solely an overprinting of oil hydrocarbon-degrading bacteria onto otherwise relatively stable sand population structures. Among sequences classified to genus, Alcanivorax, Alteromonas, Marinobacter, Winogradskyella, and Zeaxanthinibacter exhibited the largest relative abundance increases in oiled sands. PMID:24040219

  19. 109. VIEW OF SOUTHEAST SIDE OF PIER TAKEN FROM BEACH, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    109. VIEW OF SOUTHEAST SIDE OF PIER TAKEN FROM BEACH, LOOKING WEST. VIEW SHOWS ART DECO BUILDINGS ADDED IN 1931 AND 5TH TEE ADDED IN 1940 Photograph #5369-HB. Photographer unknown, c. 1945, based on clothing of sunbathers; view probably taken in mid-1945 after the U.S. Army vacated the pier and it was reopened to the public. - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  20. Summer E. coli patterns and responses along 23 Chicago beaches

    USGS Publications Warehouse

    Whitman, R.L.; Nevers, M.B.

    2008-01-01

    Concentrations of E. coli in recreational beach water are highly variable both locally and temporally, but a broader understanding of these fluctuations may be explained through coastal observations. Currently, beach contamination study approaches tend to be site-specific underthe belief that politically delineated beaches are unique and management of beaches cannot be regionally oriented. E. coli data collected over five years from 23 Chicago beaches clearly identified ambient linked patterns at the regional scale. Temporal fluctuations were similar, with all beaches having simultaneous peaks and troughs of E. coli concentrations. Spatially, E. coli concentrations for beaches more closely situated were more closely correlated, indicating spatial autocorrelation. Julian day, wave height, and barometric pressure explained up to 40% of the variation, a value comparable to individual, less parsimonious site-specific models. Day of sampling could explain the majority of the variation in E. coli concentrations, more so than beach, depth, or time of day. Comparing beaches along a targeted coastline allows a better understanding of inherent background regional fluctuations and, ultimately, better predictions of E. coli concentrations in coastal recreational water.

  1. The role of tides in beach cusp development

    NASA Astrophysics Data System (ADS)

    Coco, Giovanni; Burnet, Tom K.; Werner, B. T.; Elgar, Steve

    2004-04-01

    Field measurements of morphology and swash flow during three episodes of beach cusp development indicate that tides modulate the height and cross-shore position of beach cusps. During rising tide, beach cusp height decreases as embayments accrete more than horns and the cross-shore extent of beach cusps decreases. During falling tide, beach cusp height increases as embayments erode more than horns and cross-shore extent increases. A numerical model for beach cusp formation based on self-organization, extended to include the effects of morphological smoothing seaward of the swash front and infiltration into the beach, reproduces the observed spacing, position, and tidal modulation. During rising tide, water particles simulating swash infiltrate, preferentially in embayments, causing enhanced deposition. During falling tide, exfiltration of water particles combined with diversion of swash from horns causes enhanced erosion in embayments. Smoothing of beach morphology in the swash zone seaward of the swash front and in the shallow surf zone accounts for most of the observed tidal modulation, even in the absence of infiltration and exfiltration. Despite the qualitative, and in some cases quantitative, agreement of the model and measurements, the model fails to reproduce observed large deviations of horn orientation from shore normal, some aspects of beach cusp shape, and deviations from the basic tidal modulation, possibly because of the simplified parameterization of cross-shore sediment transport and the neglect of the effects of sea surface gradients on flow.

  2. Using a watershed-centric approach to identify potentially impacted beaches

    EPA Science Inventory

    Beaches can be affected by a variety of contaminants. Of particular concern are beaches impacted by human fecal contamination and urban runoff. This poster demonstrates a methodology to identify potentially impacted beaches using Geographic Information Systems (GIS). Since h...

  3. The influence of metal speciation on the bioavailability and sub-cellular distribution of cadmium to the terrestrial isopod, Porcellio dilatatus.

    PubMed

    Calhôa, Carla Filipa; Monteiro, Marta S; Soares, Amadeu M V M; Mann, Reinier M

    2011-04-01

    Cadmium is a non-essential toxic metal that is able to bioaccumulate in both flora fauna and has the potential to biomagnify in some food chains. However, the form in which cadmium is presented to consumers can alter the bioavailability and possibly the internal distribution of assimilated Cd. Previous studies in our laboratory highlighted differences in Cd assimilation among isopods when they were provided with a plant-based food with either Cd biologically incorporated into plant tissue or superficially amended with ionic Cd(2+). Cd is known for its high affinity for sulphur ligands in cysteine residues which form the basis for metal-binding proteins such as metallothionein. This study compares Cd assimilation efficiency (AE) in Porcellio dilatatus fed with food amended with either cadmium cysteinate or cadmium nitrate in an examination of the influence of Cd speciation on metal bioavailability followed by an examination of the sub-cellular distribution using a centrifugal fractionation protocol. As hypothesized the AE of Cd among isopods fed with Cd(NO(3))(2) (64%, SE=5%) was higher than AE for isopods fed with Cd(Cys)(2) (20%, SE=3%). The sub-cellular distribution also depended on the Cd species provided. Those isopods fed Cd(Cys)(2) allocated significantly more Cd to the cell debris and organelles fractions at the expense of allocation to metal-rich granules (MRG). The significance of the difference in sub-cellular distribution with regard to toxicity is discussed. This paper demonstrates that the assimilation and internal detoxification of Cd is dependent on the chemical form of Cd presented to the isopod. PMID:21215989

  4. Beyond beach width: Steps toward identifying and integrating ecological envelopes with geomorphic features and datums for sandy beach ecosystems

    NASA Astrophysics Data System (ADS)

    Dugan, Jenifer E.; Hubbard, David M.; Quigley, Brenna J.

    2013-10-01

    Our understanding of ecological responses to climatic and anthropogenic forcing lags far behind that of physical or geomorphic responses for beach ecosystems. Reconciling geomorphic features of beaches with ecological features, such as intertidal zones and mobile biota that are not described by beach width alone, could help address this issue. First, although intertidal zones characterized by distinct groups of mobile burrowing animals are described for beaches, the locations and elevations of these zones do not coincide with standard shoreline datums. Second, intertidal zonation on beaches is extremely dynamic due to the combination of unstable sandy substrate and a highly mobile biota; shifting strongly with tides, waves, storms, and beach conditions. We propose that beach biota use ecological "envelopes" of cross-shore habitat to cope with constantly changing beach conditions. We estimated the extent of these "envelopes" for a variety of taxa on tidal to daily, semi-lunar and seasonal to annual time scales, using literature values on cross-shore animal movements and a field study of the positions of intertidal beds of two species of typical mid and upper shore beach invertebrates. Daily or tidal cross-shore movement varied most (1 m to 100 m) with daily "envelopes" covering 7% to 85% of the available beach width. Semi-lunar movement (12 m) and envelopes (28%) were relatively small, while estimated annual "envelopes" were large, averaging 61% of beach width. The large scope of annual ecological envelopes relative to beach widths reflects how intertidal animals escape seasonally extreme or episodically harsh conditions. Intertidal bed positions of a talitrid amphipod and an opheliid polychaete correlated well with selected beach features in our field study suggesting that incorporation of ecological envelopes in models of shoreline evolution may be feasible. Describing ecological zones in terms of more dynamic shoreline features, such as total water level (TWL) that incorporate wave setup and runup, may be particularly applicable to upper intertidal biota whose distributions closely followed the high tide strand line (HTS), a feature which tracks total water level (TWL). Developing a TWL approach may also provide new insights on habitat availability for beach nesting wildlife and coastal strand vegetation. Conservation of beach ecosystems could be enhanced by incorporating sufficient beach habitat to accommodate the dynamic ecological envelopes used by mobile intertidal invertebrates and wildlife.

  5. 75 FR 41926 - Noise Exposure Map Notice New Smyrna Beach Municipal Airport, New Smyrna Beach, FL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-19

    ... Federal Aviation Administration Noise Exposure Map Notice New Smyrna Beach Municipal Airport, New Smyrna... Administration (FAA) announces its determination that the Noise Exposure Maps submitted by the City of New Smyrna... Safety and Noise Abatement Act) and 14 CFR Part 150 are in compliance with applicable requirements....

  6. NOWCASTING AND FORECASTING BEACH BACTERIA CONCENTRATION USING THE EPA VIRTUAL BEACH SOFTWARE

    EPA Science Inventory

    Beaches are subject to closure when bacterial counts exceed water quality criteria. Many authorities base these decisions on sample counts, which typically require a day or more to analyze. Sometimes called the persistence model, because conditions are assumed to persist, experie...

  7. MEETING IN MEXICO: NOWCASTING AND FORECASTING BEACH BACTERIA CONCENTRATION USING EPA'S VIRTUAL BEACH SOFTWARE

    EPA Science Inventory

    Beaches in the United States of (North) America are subject to closure when bacterial counts exceed water quality criteria. Many authorities base these decisions on water samples that typically require at least 18 hours to analyze. This persistence approach, or model, often leads...

  8. Campus Planning Study for Daytona Beach Junior College, Daytona Beach, Florida.

    ERIC Educational Resources Information Center

    Caudill, Rowlett and Scott, Architects, Houston, TX.

    Major considerations and findings are presented in regard to the updating of a long range campus plan for the development of buildings, parking areas, drives and sidewalks at Daytona Beach Junior College. Following a consideration of the background and program of the college, a site analysis is presented. Plans and recommendations are offered…

  9. 77 FR 27120 - Safety Zone; Virginia Beach Oceanfront Air Show, Atlantic Ocean, Virginia Beach, VA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-09

    ..., Virginia Beach, VA in the Federal Register (76 FR 13519). We received one comment on the proposed rule. No... and Interference with Constitutionally Protected Property Rights. Civil Justice Reform This rule meets applicable standards in sections 3(a) and 3(b)(2) of Executive Order 12988, Civil Justice Reform, to...

  10. Evaluation of potential sources and transport mechanisms of fecal indicator bacteria to beach water, Murphy Park Beach, Door County, Wisconsin

    USGS Publications Warehouse

    Juckem, Paul F.; Corsi, Steven R.; McDermott, Colleen; Kleinheinz, Gregory; Fogarty, Lisa R.; Haack, Sheridan K.; Johnson, Heather E.

    2013-01-01

    Fecal Indicator Bacteria (FIB) concentrations in beach water have been used for many years as a criterion for closing beaches due to potential health concerns. Yet, current understanding of sources and transport mechanisms that drive FIB occurrence remains insufficient for accurate prediction of closures at many beaches. Murphy Park Beach, a relatively pristine beach on Green Bay in Door County, Wis., was selected for a study to evaluate FIB sources and transport mechanisms. Although the relatively pristine nature of the beach yielded no detection of pathogenic bacterial genes and relatively low FIB concentrations during the study period compared with other Great Lakes Beaches, its selection limited the number of confounding FIB sources and associated transport mechanisms. The primary sources of FIB appear to be internal to the beach rather than external sources such as rivers, storm sewer outfalls, and industrial discharges. Three potential FIB sources were identified: sand, swash-zone groundwater, and Cladophora mats. Modest correlations between FIB concentrations in these potential source reservoirs and FIB concentrations at the beach from the same day illustrate the importance of understanding transport mechanisms between FIB sources and the water column. One likely mechanism for transport and dispersion of FIB from sand and Cladophora sources appears to be agitation of Cladophora mats and erosion of beach sand due to storm activity, as inferred from storm indicators including turbidity, wave height, current speed, wind speed, sky visibility, 24-hour precipitation, and suspended particulate concentration. FIB concentrations in beach water had a statistically significant relation (p-value ‹0.05) with the magnitude of these storm indicators. In addition, transport of FIB in swash-zone groundwater into beach water appears to be driven by groundwater recharge associated with multiday precipitation and corresponding increased swash-zone groundwater discharge at the beach, as indicated by an increase in the specific conductance of beach water. Understanding the dynamics of FIB sources (sand, swash-zone groundwater, and Cladophora) and transport mechanisms (dispersion and erosion from storm energy, and swash-zone groundwater discharge) is important for improving predictions of potential health risks from FIB in beach water.

  11. Alongshore variability in beach planform, grain-size distribution and foredune height of an embayed beach: Shoalwater Bay, Queensland, Australia

    NASA Astrophysics Data System (ADS)

    Weymer, B. A.; Houser, C.; Giardino, R.

    2012-12-01

    Headland-bay beaches (HBB) are common beach-types found throughout the coastlines of the world. Morphodynamics of these structurally-controlled beaches are primarily governed by geological inheritance, wave climate, tidal range and grain-size distribution, which ultimately influence sediment transport across the beach-dune system. For embayed beaches, the degree of curvature (i.e., indentation ratio) has significant implications for littoral cell circulation, which mediates both cross-shore and alongshore sediment transport. This study investigated the morphodynamic controls on longshore and cross-shore sediment transport for a macro-tidal, embayed beach in central Queensland, Australia. Freshwater Beach is a 10 km long embayed beach located in the Shoalwater Bay Training Area, ~50 km north of Yeppoon. Freshwater Beach exhibits an asymmetrical planform which is characterized by a curved "shadow zone" (adjacent to the headland), transitioning to a straight tangential segment extending to the north. The beach is subjected to a mean tidal range of 6 m and prevailing onshore-directed winds and swell from the southeast. A total of 12 topographic profiles at ~1 km spacing were taken along the entire length of the beach to characterize variation in beach slope and foredune height. Sediment samples were collected across each transect for detailed grain-size and geochemical (XRD/XRF and SEM) analysis. Additionally, ground-based LiDAR surveys were conducted along the topographic profiles and for comparison with aerial-based LiDAR surveys. Preliminary results from topographic profiles show that the largest foredunes are located in the central portion of the beach, contrary to most embayed beaches where the largest dunes are typically located downdrift of the headland. Along the exposed section, the foredunes become large (~15 m high) and are hypothesized to be supplied by onshore welded bars that act as a sediment source for the foredunes to grow. Presently the alongshore and cross-shore sediment exchange is unknown and the dynamics of surface drainage and freshwater seeps in close proximity to the outlet of Freshwater Swamp remain a priority for understanding the morphologic evolution of the beach-dune system. Ongoing research is currently in progress to address relationships between grain-size grading alongshore and foredune height to determine a sediment budget from the nearshore extending through the parabolic dunefield.

  12. 17. TURNTABLE RECONSTRUCTION BEACH & HYDE: Photocopy of May ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. TURNTABLE RECONSTRUCTION - BEACH & HYDE: Photocopy of May 1956 photograph of the turntable at Beach and Hyde Streets. View to the north. Note position of the tracks atop the turntable and details of the steel members that support the wooden decking. - San Francisco Cable Railway, Washington & Mason Streets, San Francisco, San Francisco County, CA

  13. At Long Beach, Success Is Measured by Degrees

    ERIC Educational Resources Information Center

    Fain, Paul

    2009-01-01

    The California State University campus at Long Beach graduated 8,720 students last month. Each one got the opportunity to walk the stage, and F. King Alexander, the university's president, shook every hand. California State at Long Beach has made graduating a greater number of its 38,000 students its top priority. The slogan "Graduation Begins…

  14. Dramatic Improvements in Beach Water Quality Following Gull Removal

    EPA Science Inventory

    Gulls are often cited as important contributors of fecal contamination to surface waters, and some recreational beaches have used gull control measures to improve microbial water quality. In this study, gulls were chased from a Lake Michigan beach using specially trained dogs, a...

  15. 270. OFFICERS' QUARTERS (FORMER SUMMER COTTAGES) AT DOG PATCH BEACH, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    270. OFFICERS' QUARTERS (FORMER SUMMER COTTAGES) AT DOG PATCH BEACH, C. 1939. VIEW NORTH DOWN GREENWICH ROAD TOWARD FORMER SUMMER COTTAGES, CONVERTED TO OFFICER'S QUARTERS, OVER-LOOKING DOG PATCH BEACH. - Quonset Point Naval Air Station, Roger Williams Way, North Kingstown, Washington County, RI

  16. Bodies that Matter: Performing White Possession on the Beach

    ERIC Educational Resources Information Center

    Moreton-Robinson, Aileen

    2011-01-01

    Beaches remain important places within indigenous coastal peoples' territories, although the silence about our ownership is deafening. Many authors have argued that within Australian popular culture the beach is a key site where racialized and gendered transgressions, fantasies, and desires are played out, but none have elucidated how these…

  17. Falcon Beach School Closure Review. Research 87-01.

    ERIC Educational Resources Information Center

    Manitoba Dept. of Education, Winnipeg. Planning and Research Branch.

    Falcon Beach School is a small school experiencing declining school enrollment and increasing operational costs. In February, 1987, Falcon Beach School was announced as a candidate for closure. The Planning and Research Branch of Manitoba Education conducted an economic and social analysis of the school operations. This research report provides…

  18. Composite analysis for Escherichia coli at coastal beaches

    USGS Publications Warehouse

    Bertke, E.E.

    2007-01-01

    At some coastal beaches, concentrations of fecal-indicator bacteria can differ substantially between multiple points at the same beach at the same time. Because of this spatial variability, the recreational water quality at beaches is sometimes determined by stratifying a beach into several areas and collecting a sample from each area to analyze for the concentration of fecal-indicator bacteria. The average concentration of bacteria from those points is often used to compare to the recreational standard for advisory postings. Alternatively, if funds are limited, a single sample is collected to represent the beach. Compositing the samples collected from each section of the beach may yield equally accurate data as averaging concentrations from multiple points, at a reduced cost. In the study described herein, water samples were collected at multiple points from three Lake Erie beaches and analyzed for Escherichia coli on modified mTEC agar (EPA Method 1603). From the multiple-point samples, a composite sample (n = 116) was formed at each beach by combining equal aliquots of well-mixed water from each point. Results from this study indicate that E. coli concentrations from the arithmetic average of multiple-point samples and from composited samples are not significantly different (t = 1.59, p = 0.1139) and yield similar measures of recreational water quality; additionally, composite samples could result in a significant cost savings.

  19. The Beach--A Natural Protection from the Sea.

    ERIC Educational Resources Information Center

    Sensabaugh, William M.

    1983-01-01

    The beach and sand dunes are the first line of defense protecting the land from the sea. The effectiveness of the beach is caused by its sloping surface which dissipates the energy of waves and by the flexibility of the slope which changes as the waves change. The process and rate of accretion and erosion are dependent on the size and frequency of…

  20. Geographic setting influences Great Lakes beach microbiological water quality

    USGS Publications Warehouse

    Haack, Sheridan K.; Fogarty, Lisa R.; Stelzer, Erin A.; Fuller, Lori M.; Brennan, Angela K.; Isaacs, Natasha M.; Johnson, Heather E.

    2013-01-01

    Understanding of factors that influence Escherichia coli (EC) and enterococci (ENT) concentrations, pathogen occurrence, and microbial sources at Great Lakes beaches comes largely from individual beach studies. Using 12 representative beaches, we tested enrichment cultures from 273 beach water and 22 tributary samples for EC, ENT, and genes indicating the bacterial pathogens Shiga-toxin producing E. coli (STEC), Shigella spp., Salmonella spp, Campylobacter jejuni/coli, and methicillin-resistant Staphylococcus aureus, and 108–145 samples for Bacteroides human, ruminant, and gull source-marker genes. EC/ENT temporal patterns, general Bacteroides concentration, and pathogen types and occurrence were regionally consistent (up to 40 km), but beach catchment variables (drains/creeks, impervious surface, urban land cover) influenced exceedances of EC/ENT standards and detections of Salmonella and STEC. Pathogen detections were more numerous when the EC/ENT Beach Action Value (but not when the Geometric Mean and Statistical Threshold Value) was exceeded. EC, ENT, and pathogens were not necessarily influenced by the same variables. Multiple Bacteroides sources, varying by date, occurred at every beach. Study of multiple beaches in different geographic settings provided new insights on the contrasting influences of regional and local variables, and a broader-scale perspective, on significance of EC/ENT exceedances, bacterial sources, and pathogen occurrence.

  1. At Long Beach, Success Is Measured by Degrees

    ERIC Educational Resources Information Center

    Fain, Paul

    2009-01-01

    The California State University campus at Long Beach graduated 8,720 students last month. Each one got the opportunity to walk the stage, and F. King Alexander, the university's president, shook every hand. California State at Long Beach has made graduating a greater number of its 38,000 students its top priority. The slogan "Graduation Begins…

  2. Tracer Studies In Laboratory Beach Simulating Tidal Influences

    EPA Science Inventory

    Bioremediation of oil spills on tidally influenced beaches commonly involves the addition of a nutrient solution to the contaminated region of the beach at low tide to stimulate the growth of indigenous oil-degrading bacteria. Maximizing the residentce time of nutrients in the be...

  3. WATER QUALITY ASSESSMENT OF LAKE TEXOMA BEACHES, 1999-2001

    EPA Science Inventory

    A biological and inorganic assessment of five beaches on Lake Texoma was conducted from September 1999 through July 2001. Water samples for each beach site were divided into two groups, a swimming season and non-swimming season. Water properties such as temperature, alkalinity,...

  4. RECREATIONAL BEACH WATER QUALITY MONITORING WITH QUANTITATIVE POLYMERASE CHAIN

    EPA Science Inventory

    Recreational beaches are an important economic and aesthetic asset to communities, states and the nation as a whole. Considerable resources are expended each year in monitoring the water at these beaches for fecal indicator bacteria as a means of determining if it is safe for pu...

  5. Virtual Beach v2.2 User Guide

    EPA Science Inventory

    Virtual Beach version 2.2 (VB 2.2) is a decision support tool. It is designed to construct site-specific Multi-Linear Regression (MLR) models to predict pathogen indicator levels (or fecal indicator bacteria, FIB) at recreational beaches. MLR analysis has outperformed persisten...

  6. Beach morphology and coastline evolution in the southern Bohai Strait

    NASA Astrophysics Data System (ADS)

    Zhang, Wei; Wu, Jianzheng; Li, Weiran; Zhu, Longhai; Hu, Rijun; Jiang, shenghui; Sun, Yonggen; Wang, Huijuan

    2015-10-01

    The beach studied in this paper spans a length of 51 km and is one of several long sandy beaches in the southern Bohai Strait. Due to the obstruction of islands in the northeast and the influence of the underwater topography, the wave environment in the offshore area is complex; beach types and sediment transport characteristics vary along different coasts. The coastlines extracted from six aerial photographs in different years were compared to demonstrate the evolving features. Seven typical beach profiles were selected to study the lateral beach variation characteristics. Continuous wind and wave observation data from Beihuangcheng ocean station during 2009 were employed for the hindcast of the local wave environment using a regional spectral wave model. Then the results of the wave hindcast were incorporated into the LITDRIFT model to compute the sediment transport rates and directions along the coasts and analyze the longshore sand movement. The results show that the coastline evolution of sand beaches in the southern Bohai Strait has spatial and temporal variations and the coast can be divided into four typical regions. Region (I), the north coast of Qimudao, is a slightly eroded and dissipative beach with a large sediment transport rate; Region (II), the southwest coast of Gangluan Port, is a slightly deposited and dissipative beach with moderate sediment transport rate; Region (III), in the central area, is a beach that is gradually transformed from a slightly eroded dissipative beach to a moderately or slightly strong eroded bar-trough beach from west to east with a relatively moderate sediment transport rate. Region (IV), on the east coast, is a strongly eroded and reflective beach with a weak sediment transport rate. The wave conditions exhibit an increasing trend from west to east in the offshore area. The distribution of the wave-induced current inside the wave breaking region and the littoral sediment transport in the nearshore region exhibit a gradual weakening tendency from west to east, which is opposite to the trend of the wave conditions outside the breaking region. The presence of submerged shoal (Dengzhou Shoal), deep trough (Dengzhou Channel), islands and irregular topography influnces the wave climate, beach types, wave-induced current features, littoral sediment transport trends and coastline evolution patterns in the southern Bohai Strait. Human activities, such as the sand exploitation of Dengzhou Shoal and other coastal engineering projects, also influence the beach morphology and coastline evolution.

  7. Deepwater Horizon oil spill impacts on Alabama beaches

    NASA Astrophysics Data System (ADS)

    Hayworth, J. S.; Clement, T. P.; Valentine, J. F.

    2011-07-01

    From mid June 2010 to early August 2010, the white sandy beaches along Alabama's Gulf coast were inundated with crude oil discharged from the Deepwater Horizon well. The long-term consequences of this environmental catastrophe are still unfolding. Although BP has attempted to clean up some of these beaches, there still exist many unanswered questions regarding the physical, chemical, and ecological state of the oil contaminated beach system. In this paper, we present our understanding of what is known and known to be unknown with regard to the current state of Alabama's beaches in the aftermath of the Deepwater Horizon disaster. Motivated by our observations of the evolving distribution of oil in Alabama's beaches and BP's clean-up activities, we offer our thoughts on the lessons learned from this oil spill disaster.

  8. Deepwater Horizon oil spill impacts on Alabama beaches

    NASA Astrophysics Data System (ADS)

    Hayworth, J. S.; Clement, T. P.; Valentine, J. F.

    2011-12-01

    From mid June 2010 to early August 2010, the white sandy beaches along Alabama's Gulf coast were inundated with crude oil discharged from the Deepwater Horizon well. The long-term consequences of this environmental catastrophe are still unfolding. Although BP has attempted to clean up some of these beaches, there still exist many unanswered questions regarding the physical, chemical, and ecological state of the oil contaminated beach system. In this paper, we present our understanding of what is known and known to be unknown with regard to the current state of Alabama's beaches in the aftermath of the Deepwater Horizon disaster. Motivated by our observations of the evolving distribution of oil in Alabama's beaches and BP's clean-up activities, we offer our thoughts on the lessons learned from this oil spill disaster.

  9. Pore Water Transport of Enterococci out of Beach Sediments

    PubMed Central

    Phillips, Matthew C.; Solo-Gabriele, Helena M.; Reniers, Adrianus J. H. M.; Wang, John D.; Kiger, Russell T.; Abdel-Mottaleb, Noha

    2011-01-01

    Enterococci are used to evaluate the safety of beach waters and studies have identified beach sands as a source of these bacteria. In order to study and quantify the release of microbes from beach sediments, flow column systems were built to evaluate flow of pore water out of beach sediments. Results show a peak in enterococci (average of 10% of the total microbes in core) released from the sand core within one pore water volume followed by a marked decline to below detection. These results indicate that few enterococci are easily removed and that factors other than simple pore water flow control the release of the majority of enterococci within beach sediments. A significantly larger quantity and release of enterococci were observed in cores collected after a significant rain event suggesting the influx of fresh water can alter the release pattern as compared to cores with no antecedent rainfall. PMID:21945015

  10. Probabilistic assessment of beach and dune changes

    USGS Publications Warehouse

    Sallenger, A.H., Jr.; Stockdon, H.; Haines, J.; Krabill, W.; Swift, R.; Brock, J.

    2004-01-01

    The recent availability of spatially-dense airborne lidar data makes assessment of the vulnerability of beaches and dunes to storm impacts practical over long reaches of coast. As an initial test, elevations of the tops (D high) and bases (Dlow) of foredune ridges along a 55-km reach on the northern Outer Banks, NC were found to have considerable spatial variability suggesting that different parts of the barrier island would respond differently to storms. Comparing statistics of storm wave runup to D high and Dlow, we found that net erosion due to overwash and dune retreat should be greatest at the northern and southern ends of the study area and least in the central section. This predicted spatial pattern of storm-induced erosion is similar to the spatial pattern of long-term erosion of the shoreline which may be controlled by additional processes (such as gradients in longshore transport) as well as the cross-shore processes considered here. However, consider feedback where at erosional hot spots there is a deficit of sand (caused by gradients in longshore transport) which lead to lower dunes and enhanced erosional cross-shore processes, such as overwash. Hence, the erosional hot spots would be exacerbated, further increasing the vulnerability of the beach and dunes to net erosion.

  11. THE VISUAL BEACH NUMERICAL MODEL: A DIAGNOSTIC AND PROGNOSTIC MODELING APPROACH TO ACHIEVING US BEACHES AESTHETIC AND PUBLIC HEALTH PROTECTION

    EPA Science Inventory

    Under the BEACH Act of 2000, EPA has committed to a program to monitor beach water quality and develop strategies, including modeling, for timely notification of the public when bacterial contamination poses a risk to bathers. EPA's goal is to manage 100% of significant public be...

  12. USING TODAY'S DATA TO CLOSE THE BEACH TODAY. QUANTITATIVE POLYMERASE CHAIN REACTION (QPCR) RAPID BEACH CLOSINGS TOOL

    EPA Science Inventory

    Recreational beaches are an important economic and aesthetic asset to communities, states and the nation as a whole. Considerable resources are expended each year in the measurement of fecal indicator bacteria concentrations in the water at these beaches to determine whether thes...

  13. USING TODAY'S DATA TO CLOSE THE BEACH TODAY. QUANTITATIVE POLYMERASE CHAIN REACTION (QPCR) RAPID BEACH CLOSING TOOL

    EPA Science Inventory

    Recreational beaches are an important economic and aesthetic asset to communities, states and the nation as a whole. Considerable resources are expended each year in the measurement of fecal indicator bacteria concentrations in the water at these beaches to determine whether thes...

  14. The relationship between sandy beach nematodes and environmental characteristics in two Brazilian sandy beaches (Guanabara Bay, Rio de Janeiro).

    PubMed

    Maria, Tatiana F; Paiva, Paulo; Vanreusel, Ann; Esteves, André M

    2013-03-01

    We investigated if the differences in density and nematode communities of intertidal sediments from two Brazilian sheltered sandy beaches were related to environmental characteristics. The upper tide level (UTL) and the low tide level (LTL) of both beaches were surveyed in January (austral summer) and June 2001 (austral winter) during low-spring tides, by collecting samples of nematodes and sediments. Differences in density between beaches, tidal level and seasons, and nematode community structure were investigated. Sediments from both beaches were composed of medium to very coarse sand. The highest nematode densities were found at the UTL, and significant differences between beaches, tidal levels and months were found. A total of 54 genera were found and the genera composition on both sheltered beaches was similar to other exposed worldwide sandy beaches. The density and structure of the nematode community at both beaches clearly varied along the spatial and temporal scales. Gravel percentage was the most important variable explaining the spatial distribution of the nematodes, determining the four sub-communities; this suggests that the sediment characteristics influence the nematode community, rather than physical hydrodynamic forces. Temperature and salinity were suggested to be important variables affecting the temporal variation. PMID:23460426

  15. 75 FR 77010 - Nextera Energy Point Beach, LLC; Point Beach Nuclear Plant, Units 1 and 2, Draft Environmental...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-10

    ... the Maximum Reactor Power Level In accordance with Title 10 of the Code of Federal Regulations (10 CFR... Florida Power & Light (FPL) Energy (the licensee) (now NextEra Energy Point Beach, LLC (NextEra)) for a license amendment to increase the maximum thermal power at the Point Beach Nuclear Plant (PBNP), Units...

  16. 76 FR 22928 - Nextera Energy Point Beach, LLC; Point Beach Nuclear Plant, Units 1 and 2; Environmental...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-25

    ... COMMISSION Nextera Energy Point Beach, LLC; Point Beach Nuclear Plant, Units 1 and 2; Environmental... amendment for Renewed Facility Operating License Nos. DPR-24 and DPR-27, issued to NextEra Energy Point... the Federal Register on December 10, 2010 (75 FR 77010). Comments were received on the draft EA...

  17. Assimilation and loss of sup 109 Cd and sup 65 Zn by the terrestrial isopods Oniscus asellus and Porcellio scaber

    SciTech Connect

    Hames, C.A.C.; Hopkin, S.P. )

    1991-09-01

    Terrestrial isopods (woodlice) have been the subject of numerous publications on the dynamics of metals in terrestrial invertebrates. They are of particular interest due to the ability of the hepatopancreas of woodlice to accumulate zinc, cadmium, lead and copper to very high concentrations. In a recent study, Hopkin showed that O. asellus from a zinc-contaminated site was able to excrete this metal at a faster rate than P. scaber when both species were fed an uncontaminated diet. In contrast, O. asellus had a greater affinity for cadmium and retained this metal to a much greater extent than P. scaber. In this paper, the rates of assimilation and excretion of two of these metals have been quantified by feeding O. asellus and P. scaber on leaves contaminated with radioactive isotopes of zinc and cadmium.

  18. The responses of artificial embayed beaches to storm events

    NASA Astrophysics Data System (ADS)

    Ojeda, E.; Guillén, J.; Ribas, F.

    2009-09-01

    The plan-view and the profile shape of sandy beaches largely depend on the incoming wave-energy (Wright and Short, 1984). In this sense, storm events are responsible for major changes in the configuration of sandy beaches and the cumulative effect of storms and fair-weather conditions determines the morphodynamic state of a certain beach. With increasing wave energy, the beach will change from the Reflective state to the Low Tide Terrace, Transverse Bar and Rip, Rhythmic Bar and Beach, Longshore Bar and Trough and finally to the Dissipative beach state. These morphodynamic states are also observed at artificial embayed beaches, although artificial groins limit alongshore sediment transport and protect sections of the beach from waves approaching from a range of directions (Short and Masselink, 1999). This contribution focuses on the morphological changes of the shoreline and the submerged sandbars of artificial embayed (sandy) beaches due to the effect of high-wave conditions associated to storms. We characterize the morphological response of the emerged and submerged beach profile of two of the artificial embayed beaches of the Barcelona city coast (NW Mediterranean). The two embayed beaches under study are single-barred beaches subject to the same climatic conditions but with different morphological characteristics. The study comprises more than 4 years of data, from November 2001 to March 2006, obtained through an Argus video system (Holman and Stanley, 2007). The extraction of the shoreline and barline locations is accomplished using 10-minute time-exposure video images. Shorelines were extracted directly from oblique images (see Ojeda and Guillén, [2008] for a complete description) and rectified afterwards. Sandbars were inferred from the rectified time-exposure video images based on the preferential wave breaking over shallow areas, so they required a minimum significant wave height (Hs) which allowed the occurrence of a clear wave-breaking pattern. The barline extraction was accomplished through an automated alongshore tracking of the intensity maxima across each beach section (Van Enckevort and Ruessink, 2001). The mean Hs during the study period was 0.71 m and the averaged peak period was 5.7 s. The wave height time series shows a cyclic behaviour, with storm periods (October-April) separated by periods of low storm activity (May-October). The two most energetic periods affecting the beaches were from October 2001 to May 2002 and from October 2003 to April 2004 (wave data were obtained from a WANA node [virtual buoy] and direct measurements of the Barcelona-Coastal buoy). Approximately 25 storm events have been identified during the study period (following Ojeda and Guillén [2008], significant storms were defined as those with Hs higher than 2.5 m during the peak of the storm and a minimum duration of 12 h with Hs greater than 1.5 m). The morphological responses of the beach to the storm action determine the morphodynamic state. These responses were grouped into five categories: shoreline advance or retreat, beach rotation, sandbar migration, formation of megacusps, and changes in the sandbar configuration (linear or crescentic shape). The intensity and frequency of these modifications were different in both beaches. Regarding the changes in the morphodynamic state of the beaches, the bar at Bogatell switched more frequently among the four intermediate morphodynamic states during the study period than the bar at La Barceloneta. The bar at La Barceloneta only underwent the complete "reset" of the nearshore morphology (i.e., abrupt change of the plan-view shape of the beach towards a Longshore Bar and Trough state) once, associated with the high-energy wave event occurring on November 2001. At this beach, the strongest storm events produced the offshore migration of the bar and a certain decrease in the bar sinuosity, but did not generate an alongshore parallel bar. Similar storms caused different effects on the two adjacent beaches and, furthermore, the effect of storms of similar characteristics at the same beach, were also different. In the final paper, we will focus on these differential behaviours in an attempt to attain a certain predictability of the beach behaviour after a storm depending on the wave characteristics and the morphodynamic configuration of the beach prior to the storm. ACKNOWLEDGMENTS This work was funded by the Spanish Ministry of Science and Technology within the project SEDMET (CTM2006-06919). The work of E. Ojeda and F. Ribas was partially supported by the Spanish government through the FPU and Juan de la Cierva programs, correspondingly. The authors would like to thank Dr. Gerben Ruessink for providing the BLIM software and Puertos del Estado for the wave data. REFERENCES Holman, R.A., Stanley, J., 2007. The history and technical capabilities of Argus. Coast. Eng. 54, 447-491. Ojeda, E., Guillén, J., 2008. Shoreline dynamics and beach rotation of artificial embayed beaches. Mar. Geol. 253, 51-62. Short, A.D., Masselink, G., 1999 Embayed and structurally controlled beaches, in: Short, A.D. (Ed.), Handbook of beach and shoreface morphodynamics. John Wiley & Son, Chichester, pp. 230-250. Van Enckevort, I.M.J., Ruessink, B.G., 2001. Effect of hydrodynamics and bathymetry on video estimates of nearshore sandbar position. J. Geophys. Res. 106, 16969-16979. Wright, L.D., Short, A.D., 1984. Morphodynamic variability of surf zones and beaches: a synthesis. Mar. Geol. 56, 93-118.

  19. Phylogeography of Supralittoral Rocky Intertidal Ligia Isopods in the Pacific Region from Central California to Central Mexico

    PubMed Central

    Hurtado, Luis A.; Mateos, Mariana; Santamaria, Carlos A.

    2010-01-01

    Background Ligia isopods are widely distributed in the Pacific rocky intertidal shores from central California to central Mexico, including the Gulf of California. Yet, their biological characteristics restrict them to complete their life cycles in a very narrow range of the rocky intertidal supralittoral. Herein, we examine phylogeographic patterns of Ligia isopods from 122 localities between central California and central Mexico. We expect to find high levels of allopatric diversity. In addition, we expect the phylogeographic patterns to show signatures of past vicariant events that occurred in this geologically dynamic region. Methodology/Principal Findings We sequenced two mitochondrial genes (Cytochrome Oxidase I and 16S ribosomal DNA). We conducted Maximum Likelihood and Bayesian phylogenetic analyses. We found many divergent clades that, in general, group according to geography. Some of the most striking features of the Ligia phylogeographic pattern include: (1) deep mid-peninsular phylogeographic breaks on the Pacific and Gulf sides of Baja peninsula; (2) within the Gulf lineages, the northern peninsula is most closely related to the northern mainland, while the southern peninsula is most closely related to the central-southern mainland; and, (3) the southernmost portion of the peninsula (Cape Region) is most closely related to the southernmost portion of mainland. Conclusions/Significance Our results shed light on the phylogenetic relationships of Ligia populations in the study area. This study probably represents the finest-scale phylogeographic examination for any organism to date in this region. Presence of highly divergent lineages suggests multiple Ligia species exist in this region. The phylogeographic patterns of Ligia in the Gulf of California and Baja peninsula are incongruent with a widely accepted vicariant scenario among phylogeographers, but consistent with aspects of alternative geological hypotheses and phylo- and biogeographic patterns of several other taxa. Our findings contribute to the ongoing debate regarding the geological origin of this important biogeographic region. PMID:20657776

  20. Seasonal reproduction and feeding ecology of giant isopods Bathynomus giganteus from the continental slope of the Yucatán peninsula

    NASA Astrophysics Data System (ADS)

    Barradas-Ortiz, Cecilia; Briones-Fourzán, Patricia; Lozano-Álvarez, Enrique

    2003-04-01

    The reproduction and feeding habits of giant isopods Bathynomus giganteus [range in body length (BL): 43-363 mm] from the continental slope of the Yucatán Peninsula, México, were studied from samples collected at depths of 359-1050 m during three research cruises conducted in winter, spring, and summer of different years. Samples taken in winter and spring yielded a large proportion of mancas and juveniles, as well as high percentages of adult females with functional oostegites and males with appendices masculinae, suggesting a peak in reproductive activity during these seasons. In contrast, the virtual absence in the summer samples of (a) mancas and small juveniles, (b) females with functional oostegites, and (c) small adult males (210-290 mm BL) with appendices masculinae, suggests a low reproductive activity of B. giganteus during summer. Stomach contents analyses were conducted on five life phases (mancas, small juveniles, large juveniles, adult females and adult males) in winter and summer. Mancas and juveniles had fuller stomachs than adults during winter, and all isopods had emptier stomachs during summer than during winter. The diet of B. giganteus was broad, but the most important food categories in all life phases were fish and squid remains, underlining the main scavenging habits of B. giganteus. However, the remaining food categories show that this species is a facultative rather than a strict scavenger and suggest some ontogenetic dietary shifts. These results were further supported by diet (Horn's) overlap indices. In the winter, high diet overlap occurred between all life phases. In the summer, adult males had a low diet overlap with adult females and large juveniles. Adult males also had a low diet overlap between summer and winter. Results from this and other studies suggest that the main reproductive activity of B. giganteus in the Yucatán slope occurs during winter and spring, when the food supply on the upper-slope is highest, particularly for the younger individuals.

  1. Conserved and convergent organization in the optic lobes of insects and isopods, with reference to other crustacean taxa.

    PubMed

    Sinakevitch, I; Douglass, J K; Scholtz, G; Loesel, R; Strausfeld, N J

    2003-12-01

    The shared organization of three optic lobe neuropils-the lamina, medulla, and lobula-linked by chiasmata has been used to support arguments that insects and malacostracans are sister groups. However, in certain insects, the lobula is accompanied by a tectum-like fourth neuropil, the lobula plate, characterized by wide-field tangential neurons and linked to the medulla by uncrossed axons. The identification of a lobula plate in an isopod crustacean raises the question of whether the lobula plate of insects and isopods evolved convergently or are derived from a common ancestor. This question is here investigated by comparisons of insect and crustacean optic lobes. The basal branchiopod crustacean Triops has only two visual neuropils and no optic chiasma. This finding contrasts with the phyllocarid Nebalia pugettensis, a basal malacostracan whose lamina is linked by a chiasma to a medulla that is linked by a second chiasma to a retinotopic outswelling of the lateral protocerebrum, called the protolobula. In Nebalia, uncrossed axons from the medulla supply a minute fourth optic neuropil. Eumalacostracan crustaceans also possess two deep neuropils, one receiving crossed axons, the other uncrossed axons. However, in primitive insects, there is no separate fourth optic neuropil. Malacostracans and insects also differ in that the insect medulla comprises two nested neuropils separated by a layer of axons, called the Cuccati bundle. Comparisons suggest that neuroarchitectures of the lamina and medulla distal to the Cuccati bundle are equivalent to the eumalacostracan lamina and entire medulla. The occurrence of a second optic chiasma and protolobula are suggested to be synapomorphic for a malacostracan/insect clade. PMID:14595766

  2. A Complex Evolutionary History in a Remote Archipelago: Phylogeography and Morphometrics of the Hawaiian Endemic Ligia Isopods

    PubMed Central

    Santamaria, Carlos A.; Mateos, Mariana; Taiti, Stefano; DeWitt, Thomas J.; Hurtado, Luis A.

    2013-01-01

    Compared to the striking diversification and levels of endemism observed in many terrestrial groups within the Hawaiian Archipelago, marine invertebrates exhibit remarkably lower rates of endemism and diversification. Supralittoral invertebrates restricted to specific coastal patchy habitats, however, have the potential for high levels of allopatric diversification. This is the case of Ligia isopods endemic to the Hawaiian Archipelago, which most likely arose from a rocky supralittoral ancestor that colonized the archipelago via rafting, and diversified into rocky supralittoral and inland lineages. A previous study on populations of this isopod from O?ahu and Kaua?i revealed high levels of allopatric differentiation, and suggested inter-island historical dispersal events have been rare. To gain a better understanding on the diversity and evolution of this group, we expanded prior phylogeographic work by incorporating populations from unsampled main Hawaiian Islands (Maui, Moloka?i, Lana?i, and Hawai?i), increasing the number of gene markers (four mitochondrial and two nuclear genes), and conducting Maximum likelihood and Bayesian phylogenetic analyses. Our study revealed new lineages and expanded the distribution range of several lineages. The phylogeographic patterns of Ligia in the study area are complex, with Hawai?i, O?ahu, and the Maui-Nui islands sharing major lineages, implying multiple inter-island historical dispersal events. In contrast, the oldest and most geographically distant of the major islands (Kaua?i) shares no lineages with the other islands. Our results did not support the monophyly of all the supralittoral lineages (currently grouped into L. hawaiensis), or the monophyly of the terrestrial lineages (currently grouped into L. perkinsi), implying more than one evolutionary transition between coastal and inland forms. Geometric-morphometric analyses of three supralittoral clades revealed significant body shape differences among them. A taxonomic revision of Hawaiian Ligia is warranted. Our results are relevant for the protection of biodiversity found in an environment subject to high pressure from disturbances. PMID:24386463

  3. A complex evolutionary history in a remote archipelago: phylogeography and morphometrics of the Hawaiian endemic Ligia isopods.

    PubMed

    Santamaria, Carlos A; Mateos, Mariana; Taiti, Stefano; DeWitt, Thomas J; Hurtado, Luis A

    2013-01-01

    Compared to the striking diversification and levels of endemism observed in many terrestrial groups within the Hawaiian Archipelago, marine invertebrates exhibit remarkably lower rates of endemism and diversification. Supralittoral invertebrates restricted to specific coastal patchy habitats, however, have the potential for high levels of allopatric diversification. This is the case of Ligia isopods endemic to the Hawaiian Archipelago, which most likely arose from a rocky supralittoral ancestor that colonized the archipelago via rafting, and diversified into rocky supralittoral and inland lineages. A previous study on populations of this isopod from O'ahu and Kaua'i revealed high levels of allopatric differentiation, and suggested inter-island historical dispersal events have been rare. To gain a better understanding on the diversity and evolution of this group, we expanded prior phylogeographic work by incorporating populations from unsampled main Hawaiian Islands (Maui, Moloka'i, Lana'i, and Hawai'i), increasing the number of gene markers (four mitochondrial and two nuclear genes), and conducting Maximum likelihood and Bayesian phylogenetic analyses. Our study revealed new lineages and expanded the distribution range of several lineages. The phylogeographic patterns of Ligia in the study area are complex, with Hawai'i, O'ahu, and the Maui-Nui islands sharing major lineages, implying multiple inter-island historical dispersal events. In contrast, the oldest and most geographically distant of the major islands (Kaua'i) shares no lineages with the other islands. Our results did not support the monophyly of all the supralittoral lineages (currently grouped into L. hawaiensis), or the monophyly of the terrestrial lineages (currently grouped into L. perkinsi), implying more than one evolutionary transition between coastal and inland forms. Geometric-morphometric analyses of three supralittoral clades revealed significant body shape differences among them. A taxonomic revision of Hawaiian Ligia is warranted. Our results are relevant for the protection of biodiversity found in an environment subject to high pressure from disturbances. PMID:24386463

  4. Cannibalism as an interacting phenotype: precannibalistic aggression is influenced by social partners in the endangered Socorro Isopod (Thermosphaeroma thermophilum).

    PubMed

    Bleakley, B H; Welter, S M; McCauley-Cole, K; Shuster, S M; Moore, A J

    2013-04-01

    Models for the evolution of cannibalism highlight the importance of asymmetries between individuals in initiating cannibalistic attacks. Studies may include measures of body size but typically group individuals into size/age classes or compare populations. Such broad comparisons may obscure the details of interactions that ultimately determine how socially contingent characteristics evolve. We propose that understanding cannibalism is facilitated by using an interacting phenotypes perspective that includes the influences of the phenotype of a social partner on the behaviour of a focal individual and focuses on variation in individual pairwise interactions. We investigated how relative body size, a composite trait between a focal individual and its social partner, and the sex of the partners influenced precannibalistic aggression in the endangered Socorro isopod, Thermosphaeroma thermophilum. We also investigated whether differences in mating interest among males and females influenced cannibalism in mixed sex pairs. We studied these questions in three populations that differ markedly in range of body size and opportunities for interactions among individuals. We found that relative body size influences the probability of and latency to attack. We observed differences in the likelihood of and latency to attack based on both an individual's sex and the sex of its partner but found no evidence of sexual conflict. The instigation of precannibalistic aggression in these isopods is therefore a property of both an individual and its social partner. Our results suggest that interacting phenotype models would be improved by incorporating a new conditional ?, which describes the strength of a social partner's influence on focal behaviour. PMID:23516960

  5. 77 FR 26229 - Meloy Channel, U.S. Coast Guard Base Miami Beach, FL; Restricted Area

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-03

    ... Department of the Army, Corps of Engineers 33 CFR Part 334 Meloy Channel, U.S. Coast Guard Base Miami Beach... the U.S. Coast Guard Base Miami Beach, Florida (Base Miami Beach). Base Miami Beach is composed of multiple U.S. Coast Guard (USCG) units, both land and waterside. The facility has one of the...

  6. TESTING A BEACH BACTERIA MODEL IN LAKE MICHIGAN AND SOUTHERN CALIFORNIA

    EPA Science Inventory

    Beach closures due to high bacterial concentrations deprive the public and disrupt the tourist industry. Almost half the Lake Michigan beaches are closed more than 10% of the time. In 1999 the six-mile long beach in Huntington Beach, California was closed in July and August. Due ...

  7. Function-related structural characters and their modifications in the hindgut epithelium of two terrestrial isopods, Armadillidium vulgare and Oniscus asellus.

    PubMed

    Coruzzi, L; Witkus, R; Vernon, G M

    1982-01-01

    Intercellular junctions of the hindgut epithelial cells of two terrestrial isopods, Armadillidium vulgare and Oniscus asellus, are described. Long septate desmosomes occupy the subluminal region while gap junctions, zonulae adherens and intercellular spaces characterize the remainder of the convoluted lateral cell borders. The specialized junctional complexes and the ultrastructural morphology of the cells indicate that the terrestrial isopod hindgut epithelium functions in transport. Using mitochondrial morphometry as an indicator of cell transport activity, it appears that the posterior hindgut of A. vulgare also participates in osmoregulation, which is not the case with O. asellus. With increased desiccation there develops a significant difference between the mitochondrial structure of the two species. The mitochondria of the former retain the active structural condition (intermediate condensed conformation) while those of the latter become swollen and damaged. PMID:7117666

  8. Nourishment practices on Australian sandy beaches: a review.

    PubMed

    Cooke, Belinda C; Jones, Alan R; Goodwin, Ian D; Bishop, Melanie J

    2012-12-30

    It is predicted that the coastal zone will be among the environments worst affected by projected climate change. Projected losses in beach area will negatively impact on coastal infrastructure and continued recreational use of beaches. Beach nourishment practices such as artificial nourishment, replenishment and scraping are increasingly used to combat beach erosion but the extent and scale of projects is poorly documented in large areas of the world. Through a survey of beach managers of Local Government Areas and a comprehensive search of peer reviewed and grey literature, we assessed the extent of nourishment practices in Australia. The study identified 130 beaches in Australia that were subject to nourishment practices between 2001 and 2011. Compared to projects elsewhere, most Australian projects were small in scale but frequent. Exceptions were nine bypass projects which utilised large volumes of sediment. Most artificial nourishment, replenishment and beach scraping occurred in highly urbanised areas and were most frequently initiated in spring during periods favourable to accretion and outside of the summer season of peak beach use. Projects were generally a response to extreme weather events, and utilised sand from the same coastal compartment as the site of erosion. Management was planned on a regional scale by Local Government Authorities, with little monitoring of efficacy or biological impact. As rising sea levels and growing coastal populations continue to put pressure on beaches a more integrated approach to management is required, that documents the extent of projects in a central repository, and mandates physical and biological monitoring to help ensure the engineering is sustainable and effective at meeting goals. PMID:23103149

  9. Synthesis study of an erosion hot spot, Ocean Beach, California

    USGS Publications Warehouse

    Barnard, Patrick L.; Hansen, Jeff E.; Erikson, Li H.

    2012-01-01

    A synthesis of multiple coastal morphodynamic research efforts is presented to identify the processes responsible for persistent erosion along a 1-km segment of 7-km-long Ocean Beach in San Francisco, California. The beach is situated adjacent to a major tidal inlet and in the shadow of the ebb-tidal delta at the mouth of San Francisco Bay. Ocean Beach is exposed to a high-energy wave climate and significant alongshore variability in forcing introduced by varying nearshore bathymetry, tidal forcing, and beach morphology (e.g., beach variably backed by seawall, dunes, and bluffs). In addition, significant regional anthropogenic factors have influenced sediment supply and tidal current strength. A variety of techniques were employed to investigate the erosion at Ocean Beach, including historical shoreline and bathymetric analysis, monthly beach topographic surveys, nearshore and regional bathymetric surveys, beach and nearshore grain size analysis, two surf-zone hydrodynamic experiments, four sets of nearshore wave and current experiments, and several numerical modeling approaches. Here, we synthesize the results of 7 years of data collection to lay out the causes of persistent erosion, demonstrating the effectiveness of integrating an array of data sets covering a huge range of spatial scales. The key findings are as follows: anthropogenic influences have reduced sediment supply from San Francisco Bay, leading to pervasive contraction (i.e., both volume and area loss) of the ebb-tidal delta, which in turn reduced the regional grain size and modified wave focusing patterns along Ocean Beach, altering nearshore circulation and sediment transport patterns. In addition, scour associated with an exposed sewage outfall pipe causes a local depression in wave heights, significantly modifying nearshore circulation patterns that have been shown through modeling to be key drivers of persistent erosion in that area.

  10. Beach boundary layer: a framework for addressing recreational water quality impairment at enclosed beaches.

    PubMed

    Grant, Stanley B; Sanders, Brett F

    2010-12-01

    Nearshore waters in bays, harbors, and estuaries are frequently contaminated with human pathogens and fecal indicator bacteria. Tracking down and mitigating this contamination is complicated by the many point and nonpoint sources of fecal pollution that can degrade water quality along the shore. From a survey of the published literature, we propose a conceptual and mathematical framework, the "beach boundary layer model", for understanding and quantifying the relative impact of beach-side and bay-side sources of fecal pollution on nearshore water quality. In the model, bacterial concentration in ankle depth water C(ankle) [bacteria L(-3)] depends on the flux m'' [bacteria L(-2) T(-1)] of fecal bacteria from beach-side sources (bather shedding, bird and dog feces, tidal washing of sediments, decaying vegetation, runoff from small drains, and shallow groundwater discharge), a cross-shore mass transfer velocity k [L T(-1)] that accounts for the physics of nearshore transport and mixing, and a background concentration C(bay) [bacteria L(-3)] attributable to bay-side sources of pollution that impact water quality over large regions (sewage outfalls, creeks and rivers): C(ankle) = m''/k + C(bay). We demonstrate the utility of the model for identifying risk factors and pollution sources likely to impact shoreline water quality, and evaluate the model's underlying assumptions using computational fluid dynamic simulations of flow, turbulence, and mass transport in a trapezoidal channel. PMID:20949912

  11. Kennedy Space Center ocean beach erosion

    NASA Technical Reports Server (NTRS)

    Mehta, A. J.; Obrien, M. P.

    1973-01-01

    Dune barrier erosion and possible breakthrough due to storm and hurricane wave activity is studied near Mosquito Lagoon, in Kennedy Space Center property. The results of a geological as well as hydrodynamic appraisal of the problem area indicate that no inlet has existed across the dune barrier since 500 A.D., and that there is little likelihood of a possible breakthrough inlet remaining open permanently, primarily because the relatively shallow lagoon does not contain enough volume of water to maintain an inlet between the ocean and the lagoon. It is therefore recommended that only minimal measures, such as closing up the man-made passes across the dunes, be carried out to ensure continuation of the action of natural beach maintaining processes.

  12. Toxicokinetics of Ag in the terrestrial isopod Porcellionides pruinosus exposed to Ag NPs and AgNO3 via soil and food.

    PubMed

    Tourinho, Paula S; van Gestel, Cornelis A M; Morgan, A John; Kille, Peter; Svendsen, Claus; Jurkschat, Kerstin; Mosselmans, J Fred W; Soares, Amadeu M V M; Loureiro, Susana

    2016-03-01

    Silver nanoparticles (Ag NPs) have been used in numerous consumer products and may enter the soil through the land application of biosolids. However, little is known about the relationship between Ag NP exposure and their bioavailability for soil organisms. This study aims at comparing the uptake and elimination kinetics of Ag upon exposures to different Ag forms (NPs and ionic Ag (as AgNO3)) in the isopod Porcellionides pruinosus. Isopods were exposed to contaminated Lufa 2.2 soil or alder leaves as food. Uptake and elimination rate constants for soil exposure did not significantly differ between Ag NPs and ionic Ag at 30 and 60 mg Ag/kg. For dietary exposure, the uptake rate constant was up to 5 times higher for Ag NPs than for AgNO3, but this was related to feeding activity and exposure concentrations, while no difference in the elimination rate constants was found. When comparing both routes, dietary exposure resulted in lower Ag uptake rate constants but elimination rate constants did not differ. A fast Ag uptake was observed from both routes and most of the Ag taken up seemed not to be eliminated. Synchrotron X-ray fluorescence showed Ag in the S-cells of the hepatopancreas, thus supporting the observations from the kinetic experiment (i.e. low elimination). In addition, our results show that isopods have an extremely high Ag accumulation capacity, suggesting the presence of an efficient Ag storage compartment. PMID:26581474

  13. The distribution and abundance of Sphaeroma terebrans, a wood-boring isopod of red mangrove (Rhizophora mangle) habitat within Tampa Bay

    USGS Publications Warehouse

    Brooks, R.A.; Bell, S.S.

    2005-01-01

    This study was conducted to determine the distribution, abundance, and demography of a wood boring isopod, Sphaeroma terebrans Bate, 1866, within the prop roots of the red mangrove, Rhizophora mangle L., in eight sites within Tampa Bay, Florida. Sphaeroma terebrans in Tampa Bay displayed reproductive activity year-round and bay-wide synchrony in their density pattern. On average approximately 60% (range: 25%-86%) of the intertidal aerial roots surveyed were occupied by S. terebrans. Although infestation levels by S. terebrans in Tampa Bay were similar to that of more tropical regions, the distribution of S. terebrans was not continuous throughout the study sites. A substantially higher occurrence and density of S. terebrans was found in the northern compared to more southern study sites within the Bay. Additionally, some seemingly suitable areas of the bay (i.e., Pinellas Point, Skyway, Fort Desoto) were actually unoccupied on some dates. Although sites differed in the frequency with which roots were attacked, the density of burrows and isopods in an occupied root was similar, with most attacked roots containing 3-5 burrows. The results of a transplantation experiment indicated that neither abiotic factors nor substrate quality limit the burrowing capabilities or survival of adult S. terebrans in the areas where they are absent. Instead, dispersal limitation, linked with differential juvenile survival, most likely controls isopod distribution and abundance within Tampa Bay.

  14. Upon exposure to Cu nanoparticles, accumulation of copper in the isopod Porcellio scaber is due to the dissolved Cu ions inside the digestive tract.

    PubMed

    Golobi?, Miha; Jemec, Anita; Drobne, Damjana; Romih, Tea; Kasemets, Kaja; Kahru, Anne

    2012-11-01

    The fate of nanoparticles in organisms is of significant interest. In the current work, we used a test system with terrestrial isopods (Porcellio scaber) fed with food spiked with Cu NPs or soluble Cu salt for 14 days. Two different doses were used for spiking to yield final concentrations of 2000 and 5000 ?g Cu/g dry food. After the exposure period, part of the exposed group of animals was transferred to clean food to depurate. Cu content was analyzed in the digestive glands, gut, and the 'rest' of the body. Similar patterns of (i) assimilated and depurated amounts of Cu, (ii) Cu body distribution, and (iii) effect on isopods feeding behavior were observed regardless of whether the animals were fed with Cu NPs or soluble Cu salt spiked food. Thus, Cu ions and not Cu NPs were assimilated by the digestive gland cells. Solubilization of the Cu NPs applied to the leaves was also analyzed with chemical methods and recombinant Cu-sensing bacteria. The comparison of the in vitro data on solubilization of Cu NPs and in vivo data on Cu accumulation in the animal tissues showed that about 99% of accumulated copper ions was dissolved from ingested Cu NPs in the digestive system of isopods. PMID:23046103

  15. Mechanical grooming and beach award status are associated with low strandline biodiversity in Scotland

    NASA Astrophysics Data System (ADS)

    Gilburn, Andre S.

    2012-07-01

    Beach grooming and beach award status are both shown to be associated with low macroinvertebrate taxon richness in Scotland. Previous studies in California have revealed that mechanical raking to remove wrack from sandy beaches has negative ecological consequences for coastal ecosystems. In the current study the presence and absence of eight common taxa that inhabit beached wrack on sandy beaches in Scotland was assessed at 60 sites, 24 of which were groomed and 29 of which were in receipt of a beach award. On average 4.86 of the eight taxa were found to be present on ungroomed beaches, whereas only 1.13 taxa were present on groomed beaches. Thus, beach grooming seems to be having a major effect on the biodiversity of beach macroinvertebrates in Scotland. Fewer macroinvertebrate taxa were also found on award (1.5) compared to non-award (4.38) beaches. It was also revealed that award beaches were much more likely to be groomed than non-award beaches, with 69% of award beaches surveyed being groomed compared to only 6% of non-award beaches. This pattern is surprising as the awarding bodies discourage the removal of seaweed and regulations state that beached wrack should only be removed if it constitutes a nuisance. It is concluded that award status, not nuisance level, has the main factor driving most beach grooming and that this has resulted in the substantial loss of macroinvertebrate biodiversity from award beaches in Scotland. In conclusion it is shown that beach grooming has a substantial negative impact upon strandline macroinvertebrate biodiversity in Scotland and that grooming is much more likely to occur on award beaches.

  16. Effects of Rainfall on E. coli Concentrations at Door County, Wisconsin Beaches.

    PubMed

    Kleinheinz, Gregory T; McDermott, Colleen M; Hughes, Sarah; Brown, Amanda

    2009-01-01

    Rainfall and its associated storm water runoff have been associated with transport of many pollutants into beach water. Fecal material, from a variety of animals (humans, pets, livestock, and wildlife), can wash into beach water following rainfall and result in microbial contamination of the beach. Many locales around the world issue pre-emptive beach closures associated with rainfall. This study looked at eight beaches located in Door County, Wisconsin, on Lake Michigan to determine the impact of rainfall on E. coli concentrations in beach water. Water samples were collected from beach water and storm water discharge pipes during rainfall events of 5 mm in the previous 24 hours. Six of the eight beaches showed a significant association between rainfall and elevated beach water E. coli concentrations. The duration of the impact of rainfall on beach water E. coli concentrations was variable (immediate to 12 hours). Amount of rainfall in the days previous to the sampling did not have significant impact on the E. coli concentrations measured in beach water. Presence of storm water conveyance pipes adjacent to the beach did not have a uniform impact on beach water E. coli concentrations. This study suggests that each beach needs to be examined on its own with regard to rain impacts on E coli concentrations in beach water. PMID:20182543

  17. 18. SAND BEACH WITH SUNBATHERS AND UMBRELLAS. VIEW FROM SOUTHEAST. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. SAND BEACH WITH SUNBATHERS AND UMBRELLAS. VIEW FROM SOUTHEAST. NORTHWEST ELEVATION OF REFRESHMENT STAND Photocopy of 1930-1940 photograph - Glen Echo Park, Crystal Swimming Pool, 7300 McArthur Boulevard, Glen Echo, Montgomery County, MD

  18. 11. BEACH TOILET BUILDING, OFFICE AND FIRST AID BUILDING, PLANS, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. BEACH TOILET BUILDING, OFFICE AND FIRST AID BUILDING, PLANS, ELEVATIONS AND SECTIONS Drawing No. 103-07 - Glen Echo Park, Crystal Swimming Pool, 7300 McArthur Boulevard, Glen Echo, Montgomery County, MD

  19. General view looking to intersection of Beach Drive and Hume ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    General view looking to intersection of Beach Drive and Hume Drive - National Park Seminary, Bounded by Capitol Beltway (I-495), Linden Lane, Woodstove Avenue, & Smith Drive, Silver Spring, Montgomery County, MD

  20. 2. VIEW SHOWING NATURAL SAND BEACH ON KIDNEY LAKE, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. VIEW SHOWING NATURAL SAND BEACH ON KIDNEY LAKE, LOOKING WEST - High Mountain Dams in Upalco Unit, Kidney Lake Dam, Ashley National Forest, 4.7 miles North of Miners Gulch Campground, Mountain Home, Duchesne County, UT

  1. Measuring the effects of stormwater mitigation on beach attendance.

    PubMed

    Atiyah, Perla; Pendleton, Linwood; Vaughn, Ryan; Lessem, Neil

    2013-07-15

    Many studies have used valuation techniques to predict the potential effect of environmental improvements on human use of coastal areas, but there is a lack of post hoc empirical evidence that these policies indeed affect the way people use coastal areas. A panel data approach is developed to statistically determine how storm drain diversions affected attendance at 26 beaches in Southern California. This study uses a 10-year time series of data to conduct a statistical analysis of attendance at beaches with and without diversions and before and after the diversions were installed, while controlling for all observable, confounding factors. Results indicate that beach attendance increased at beaches with diversions compared to those that did not have diversions (between 350,000 and 860,000 visits annually at a 95% confidence interval). Establishing this link between mitigation policies and human use patterns can lead to better management of coastal areas. PMID:23711842

  2. 24. Photocopy of photograph (from Division of Beaches and Parks, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. Photocopy of photograph (from Division of Beaches and Parks, State of California, Department of Natural Resources) Photographer unknown, Date unknown MAP OF SUTTER'S FORT - Sutter's Fort, L & Twenty-Seventh Streets, Sacramento, Sacramento County, CA

  3. 7. Alternate view of collapsed Panama Mount on beach. Note ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Alternate view of collapsed Panama Mount on beach. Note concrete ring, metal rail and exposed rebar. Looking 320° NW. - Fort Funston, Panama Mounts for 155mm Guns, Skyline Boulevard & Great Highway, San Francisco, San Francisco County, CA

  4. Can the gold coast beaches withstand extreme events?

    NASA Astrophysics Data System (ADS)

    Castelle, Bruno; Le Corre, Yann; Tomlinson, Rodger

    2008-02-01

    The Gold Coast sandy beaches of Queensland (Australia) are exposed to energetic wave conditions. Storms, particularly tropical cyclones, have a high potential of destruction. The Gold Coast has not experienced excessive erosive events over the past 30 years. However, some climate indicators suggest that cyclone frequency is likely to increase in response to global climate change within the near future. Over a 2-month period in early 2006, beach surveys were undertaken with a theodolite total station at four different sites. Offshore wave conditions were provided by SWAN regional wave modelling. During this study, the Gold Coast was exposed to three major storms, the first one being the second most energetic over the past 30 years. Results show a substantial variability of the beach response to these events along the Gold Coast, and that engineering structures do not have marked effects. Easterly swells have the greatest impact on the Gold Coast sub-aerial beach morphology. When low wave-energy conditions prevail, the southern Gold Coast beaches recover more quickly than the northern ones, as they are sheltered from high SE waves and draw advantage from the artificial sand bypassing system. Nevertheless, the data show that the Gold Coast beaches are exceedingly fragile. For instance, the early March decadal event considerably weakened the beaches, which resulted in surprisingly high erosion rates all along the Gold Coast during the two following annual wave events. This study suggests that the Gold Coast beaches would not be able to withstand the impact of an increased frequency of extreme events similar in scale to those of 1967.

  5. Geographic variation in sandy beach macrofauna community and functional traits

    NASA Astrophysics Data System (ADS)

    Rodil, I. F.; Compton, T. J.; Lastra, M.

    2014-10-01

    Sandy beaches are a common ocean-dominated ecosystem along the north coast of Spain. We conducted field surveys at 39 beaches distributed between 1° and 9°W, ca. 2000 km along this geographic region to document broad patterns of macrobenthic communities, and to describe their association with variables characterising both the beach environment and the characteristics of the adjacent ocean waters. Macrofaunal functional traits are considered to be an informative measure that can be useful for many ecosystem-level questions, as they are based on what organisms do (i.e., their ecological function) rather than on their identification alone. Boosted regression-trees analysis showed that the occurrence of the main taxonomic groups and feeding guilds were differentially associated with the prevailing beach features along this coastline. The occurrence (presence/absence) of molluscs was best explained by the concentration of chlorophyll-a and wave exposure whereas those of crustaceans and polychaetes were best explained by an ensemble of variables including beach slope, sea surface temperature and grain size. A comparison of the feeding guilds demonstrated that the occurrence of suspension feeders was best explained by chlorophyll-a and wave exposure, whereas the occurrence of deposit feeders was best explained by beach slope, sea surface temperature and chlorophyll-a. The occurrence of predators and scavengers was best explained by sea surface temperature and beach slope. Based on the patterns presented here, we confirm that the upwelling events that occur regularly on this coastline are a structuring agent for beach communities. Future work needs to examine the role of the oceanographic conditions of the region for they might represent the driving forces behind large-scale shifts in macrofauna communities.

  6. Evaluation of airborne topographic lidar for quantifying beach changes

    USGS Publications Warehouse

    Sallenger, A.H., Jr.; Krabill, W.B.; Swift, R.N.; Brock, J.; List, J.; Hansen, M.; Holman, R.A.; Manizade, S.; Sontag, J.; Meredith, A.; Morgan, K.; Yunkel, J.K.; Frederick, E.B.; Stockdon, H.

    2003-01-01

    A scanning airborne topographic lidar was evaluated for its ability to quantify beach topography and changes during the Sandy Duck experiment in 1997 along the North Carolina coast. Elevation estimates, acquired with NASA's Airborne Topographic Mapper (ATM), were compared to elevations measured with three types of ground-based measurements - 1) differential GPS equipped all-terrain vehicle (ATV) that surveyed a 3-km reach of beach from the shoreline to the dune, 2) GPS antenna mounted on a stadia rod used to intensely survey a different 100 m reach of beach, and 3) a second GPS-equipped ATV that surveyed a 70-km-long transect along the coast. Over 40,000 individual intercomparisons between ATM and ground surveys were calculated. RMS vertical differences associated with the ATM when compared to ground measurements ranged from 13 to 19 cm. Considering all of the intercomparisons together, RMS ??? 15 cm. This RMS error represents a total error for individual elevation estimates including uncertainties associated with random and mean errors. The latter was the largest source of error and was attributed to drift in differential GPS. The ??? 15 cm vertical accuracy of the ATM is adequate to resolve beach-change signals typical of the impact of storms. For example, ATM surveys of Assateague Island (spanning the border of MD and VA) prior to and immediately following a severe northeaster showed vertical beach changes in places greater than 2 m, much greater than expected errors associated with the ATM. A major asset of airborne lidar is the high spatial data density. Measurements of elevation are acquired every few m2 over regional scales of hundreds of kilometers. Hence, many scales of beach morphology and change can be resolved, from beach cusps tens of meters in wavelength to entire coastal cells comprising tens to hundreds of kilometers of coast. Topographic lidars similar to the ATM are becoming increasingly available from commercial vendors and should, in the future, be widely used in beach surveying.

  7. Microbes in Beach Sands: Integrating Environment, Ecology and Public Health.

    PubMed

    Whitman, Richard; Harwood, Valerie J; Edge, Thomas A; Nevers, Meredith; Byappanahalli, Muruleedhara; Vijayavel, Kannappan; Brandão, João; Sadowsky, Michael J; Alm, Elizabeth Wheeler; Crowe, Allan; Ferguson, Donna; Ge, Zhongfu; Halliday, Elizabeth; Kinzelman, Julie; Kleinheinz, Greg; Przybyla-Kelly, Kasia; Staley, Christopher; Staley, Zachery; Solo-Gabriele, Helena M

    2014-09-01

    Beach sand is a habitat that supports many microbes, including viruses, bacteria, fungi and protozoa (micropsammon). The apparently inhospitable conditions of beach sand environments belie the thriving communities found there. Physical factors, such as water availability and protection from insolation; biological factors, such as competition, predation, and biofilm formation; and nutrient availability all contribute to the characteristics of the micropsammon. Sand microbial communities include autochthonous species/phylotypes indigenous to the environment. Allochthonous microbes, including fecal indicator bacteria (FIB) and waterborne pathogens, are deposited via waves, runoff, air, or animals. The fate of these microbes ranges from death, to transient persistence and/or replication, to establishment of thriving populations (naturalization) and integration in the autochthonous community. Transport of the micropsammon within the habitat occurs both horizontally across the beach, and vertically from the sand surface and ground water table, as well as at various scales including interstitial flow within sand pores, sediment transport for particle-associated microbes, and the large-scale processes of wave action and terrestrial runoff. The concept of beach sand as a microbial habitat and reservoir of FIB and pathogens has begun to influence our thinking about human health effects associated with sand exposure and recreational water use. A variety of pathogens have been reported from beach sands, and recent epidemiology studies have found some evidence of health risks associated with sand exposure. Persistent or replicating populations of FIB and enteric pathogens have consequences for watershed/beach management strategies and regulatory standards for safe beaches. This review summarizes our understanding of the community structure, ecology, fate, transport, and public health implications of microbes in beach sand. It concludes with recommendations for future work in this vastly under-studied area. PMID:25383070

  8. Microbes in Beach Sands: Integrating Environment, Ecology and Public Health

    PubMed Central

    Whitman, Richard; Harwood, Valerie J.; Edge, Thomas A.; Nevers, Meredith; Byappanahalli, Muruleedhara; Vijayavel, Kannappan; Brandão, João; Sadowsky, Michael J.; Alm, Elizabeth Wheeler; Crowe, Allan; Ferguson, Donna; Ge, Zhongfu; Halliday, Elizabeth; Kinzelman, Julie; Kleinheinz, Greg; Przybyla-Kelly, Kasia; Staley, Christopher; Staley, Zachery; Solo-Gabriele, Helena M.

    2014-01-01

    SUMMARY Beach sand is a habitat that supports many microbes, including viruses, bacteria, fungi and protozoa (micropsammon). The apparently inhospitable conditions of beach sand environments belie the thriving communities found there. Physical factors, such as water availability and protection from insolation; biological factors, such as competition, predation, and biofilm formation; and nutrient availability all contribute to the characteristics of the micropsammon. Sand microbial communities include autochthonous species/phylotypes indigenous to the environment. Allochthonous microbes, including fecal indicator bacteria (FIB) and waterborne pathogens, are deposited via waves, runoff, air, or animals. The fate of these microbes ranges from death, to transient persistence and/or replication, to establishment of thriving populations (naturalization) and integration in the autochthonous community. Transport of the micropsammon within the habitat occurs both horizontally across the beach, and vertically from the sand surface and ground water table, as well as at various scales including interstitial flow within sand pores, sediment transport for particle-associated microbes, and the large-scale processes of wave action and terrestrial runoff. The concept of beach sand as a microbial habitat and reservoir of FIB and pathogens has begun to influence our thinking about human health effects associated with sand exposure and recreational water use. A variety of pathogens have been reported from beach sands, and recent epidemiology studies have found some evidence of health risks associated with sand exposure. Persistent or replicating populations of FIB and enteric pathogens have consequences for watershed/beach management strategies and regulatory standards for safe beaches. This review summarizes our understanding of the community structure, ecology, fate, transport, and public health implications of microbes in beach sand. It concludes with recommendations for future work in this vastly under-studied area. PMID:25383070

  9. Active osmoregulatory ion uptake across the pleopods of the isopod Idotea baltica (Pallas): electrophysiological measurements on isolated split endo- and exopodites mounted in a micro-ussing chamber.

    PubMed

    Postel, U; Becker, W; Brandt, A; Luck-Kopp, S; Riestenpatt, S; Weihrauch, D; Siebers, D

    2000-04-01

    The mechanism of active, osmoregulatory ion uptake was investigated in the pleopods of the marine isopod Idotea baltica (Pallas). Using isolated split half-podites of isopods acclimated to brackish water (20 salinity) mounted in a micro-Ussing chamber and symmetrically superfused with identical haemolymph-like salines, a mean short-circuit current I(sc) of -445 microA cm(-)(2) was measured in endopodites 3-5, corresponding to an inwardly directed transcellular movement of negative charge. Application of ouabain (5 mmol l(-)(1)) to the basolateral superfusate resulted in the almost total abolition of the I(sc) (reduced from -531 to -47 microA cm(-)(2)), suggesting that the Na(+)/K(+)-ATPase is the driving force for active, electrogenic uptake of NaCl. In contrast, mean I(sc) values close to zero were found in preparations of all exopodites and in endopodites 1 and 2. The specific activities of Na(+)/K(+)-ATPase corresponded with these results. Specific activities were highest in posterior endopodites 3-5 and depended on ambient salinity. In all other rami, the activities were much lower and independent of ambient salinity. Activities in posterior endopodites 3-5 were lowest in isopods acclimated to 30 salinity (2-4 micromol P(i )mg(-)(1 )protein h(-)(1)), increased in individuals kept in 20 salinity (8.4 micromol P(i )mg(-)(1 )protein h(-)(1)) and were highest in isopods acclimated to 15 salinity (18.2 micromol P(i )mg(-)(1 )protein h(-)(1)). When specimens were transferred from 30 to 40 salinity, Na(+)/K(+)-ATPase activity increased in the posterior endopodites. The electrophysiological and Na(+)/K(+)-ATPase activity measurements show that active electrogenic ion transport in this species occurs almost exclusively in posterior endopodites 3-5. The endopodite of the fifth pleopod of I. baltica exhibited a microscopic structure remarkably similar to that described for the lamellae of the phyllobranchiae of brachyurans. It is composed of two opposed epithelial monolayers of ionocytes, each covered by cuticle. Bundles of pillar cells are located within the ionocyte layers, which are separated by a fenestrated lamellar septum of connective tissue. The results obtained in this study indicate that endopodites 3-5 play the main role in osmoregulatory ion uptake of the isopod I. baltica. Moreover, the Na(+)/K(+)-ATPase is the only driving force behind active electrogenic ion uptake across the epithelial cells. PMID:10708635

  10. Marine debris contamination along undeveloped tropical beaches from northeast Brazil.

    PubMed

    Santos, Isaac R; Friedrich, Ana Cláudia; Ivar do Sul, Juliana Assunção

    2009-01-01

    We hypothesize that floating debris leaving polluted coastal bays accumulate on nearby pristine beaches. We examined composition, quantities and distribution of marine debris along approximately 150 km of relatively undeveloped, tropical beaches in Costa do Dendê (Bahia, Brazil). The study site is located south of Salvador City, the largest urban settlement from NE Brazil. Strong spatial variations were observed. Plastics accounted for 76% of the sampled items, followed by styrofoam (14%). Small plastic fragments resultant from the breakdown of larger items are ubiquitous all over the area. Because the dominant littoral drift in Bahia is southward, average beach debris densities (9.1 items/m) along Costa do Dendê were threefold higher than densities previously observed north of Salvador City. River-dominated and stable beaches had higher debris quantities than unstable, erosional beaches. Areas immediately south of the major regional embayments (Camamu and Todos os Santos) were the preferential accumulation sites, indicating that rivers draining populous areas are the major source of debris to the study site. Our results provide baseline information for future assessments. Management actions should focus on input prevention at the hydrographic basin level rather than on cleaning services on beaches. PMID:18256899

  11. Coastal processes influencing water quality at Great Lakes beaches

    USGS Publications Warehouse

    U.S. Geological Survey

    2013-01-01

    In a series of studies along the Great Lakes, U.S. Geological Survey scientists are examining the physical processes that influence concentrations of fecal indicator bacteria and related pathogens at recreational beaches. These studies aim to estimate human health risk, improve management strategies, and understand the fate and transport of microbes in the nearshore area. It was determined that embayed beaches act as traps, accumulating Escherichia coli (E. coli) and other bacteria in the basin and even in beach sand. Further, shear stress and wave run-up could resuspend accumulated bacteria, leading to water-contamination events. These findings are being used to target beach design and circulation projects. In previous research, it was determined that E. coli followed a diurnal pattern, with concentrations decreasing throughout the day, largely owing to solar inactivation, but rebounding overnight. Studies at a Chicago beach identified the impact of wave-induced mass transport on this phenomenon, a finding that will extend our understanding of bacterial fate in the natural environment. In another series of studies, scientists examined the impact of river outfalls on bacteria concentrations, using mechanistic and empirical modeling. Through these studies, the models can indicate range and extent of impact, given E. coli concentration in the source water. These findings have been extended to extended lengths of coastlines and have been applied in beach management using empirical predictive modeling. Together, these studies are helping scientists identify and eliminate threats to human and coastal health.

  12. Global diversity patterns in sandy beach macrofauna: a biogeographic analysis

    NASA Astrophysics Data System (ADS)

    Rafael Barboza, Francisco; Defeo, Omar

    2015-09-01

    Unlike the advances generated on land, the knowledge of global diversity patterns in marine ecosystems is limited to a small number of studies. For sandy beaches, which dominate the world’s ocean shores, previous meta-analyses highlighted the role of beach morphodynamics in explaining species richness patterns. Oceanographic variables and historical processes have not been considered, even though they could be main predictors of community structure. Our work, based on 256 sandy beaches around the world, analysed species richness considering for the first time temperature, salinity and primary productivity. Biogeographic units (realms, provinces and ecoregions) were used to incorporate historical factors in modelling processes. Ecoregions, which implicitly include isolation and coastal complexity among other historical geographic factors, best represented trends in species richness worldwide. Temperature was a main predictor of species richness, which increased from temperate to tropical sandy beaches. Species richness increased with tide range and towards wide beaches with gentle slopes and fine grains, which is consistent with the hypothesis that habitat availability has an important role in structuring sandy beach communities. The role of temperature and habitat availability suggests that ocean warming and sea level rise could affect the distribution of obligate species living in these narrow ecosystems.

  13. Global diversity patterns in sandy beach macrofauna: a biogeographic analysis.

    PubMed

    Barboza, Francisco Rafael; Defeo, Omar

    2015-01-01

    Unlike the advances generated on land, the knowledge of global diversity patterns in marine ecosystems is limited to a small number of studies. For sandy beaches, which dominate the world's ocean shores, previous meta-analyses highlighted the role of beach morphodynamics in explaining species richness patterns. Oceanographic variables and historical processes have not been considered, even though they could be main predictors of community structure. Our work, based on 256 sandy beaches around the world, analysed species richness considering for the first time temperature, salinity and primary productivity. Biogeographic units (realms, provinces and ecoregions) were used to incorporate historical factors in modelling processes. Ecoregions, which implicitly include isolation and coastal complexity among other historical geographic factors, best represented trends in species richness worldwide. Temperature was a main predictor of species richness, which increased from temperate to tropical sandy beaches. Species richness increased with tide range and towards wide beaches with gentle slopes and fine grains, which is consistent with the hypothesis that habitat availability has an important role in structuring sandy beach communities. The role of temperature and habitat availability suggests that ocean warming and sea level rise could affect the distribution of obligate species living in these narrow ecosystems. PMID:26411697

  14. Global diversity patterns in sandy beach macrofauna: a biogeographic analysis

    PubMed Central

    Rafael Barboza, Francisco; Defeo, Omar

    2015-01-01

    Unlike the advances generated on land, the knowledge of global diversity patterns in marine ecosystems is limited to a small number of studies. For sandy beaches, which dominate the world’s ocean shores, previous meta-analyses highlighted the role of beach morphodynamics in explaining species richness patterns. Oceanographic variables and historical processes have not been considered, even though they could be main predictors of community structure. Our work, based on 256 sandy beaches around the world, analysed species richness considering for the first time temperature, salinity and primary productivity. Biogeographic units (realms, provinces and ecoregions) were used to incorporate historical factors in modelling processes. Ecoregions, which implicitly include isolation and coastal complexity among other historical geographic factors, best represented trends in species richness worldwide. Temperature was a main predictor of species richness, which increased from temperate to tropical sandy beaches. Species richness increased with tide range and towards wide beaches with gentle slopes and fine grains, which is consistent with the hypothesis that habitat availability has an important role in structuring sandy beach communities. The role of temperature and habitat availability suggests that ocean warming and sea level rise could affect the distribution of obligate species living in these narrow ecosystems. PMID:26411697

  15. Physical modeling of three-dimensional intermediate beach morphodynamics

    NASA Astrophysics Data System (ADS)

    Michallet, H.; Castelle, B.; BarthéLemy, E.; Berni, C.; Bonneton, P.

    2013-06-01

    Experiments have been performed in a large wave tank in order to study the morphodynamics of rip current systems. Both accretive and erosive shore-normal wave conditions were applied, the beach evolving through all the states within the intermediate beach classification, under the so-called down-state (accretive) and up-state (erosive) morphological transitions. Results show that any prescribed change in the wave conditions drastically increases the rate at which the morphology changes. The surf zone morphology tends toward a steady state when running a given wave climate for a long duration. We quantitatively describe a full down-state sequence characterized by the progressive evolution of an alongshore-uniform bar successively into a crescentic plan shape, a bar and rip channel morphology, and a terrace. From the analysis of a large data set of dense Eulerian measurements and bathymetric surveys, we depict several feedback mechanisms associated with wave-driven rip current circulation, wave nonlinearities and the seabed evolution. At first, a positive feedback mechanism drives a rapid increase in the rate of morphological change, beach three-dimensionality, and rip intensity. By the time the sandbar evolves into a bar and rip morphology, a negative feedback mechanism, characterized by a decaying beach change rate and an increasing beach alongshore uniformity, overwhelms the former mechanism. An erosive sequence characterized by both an overall offshore bar migration and an increase in beach three-dimensionality is also described.

  16. 75 FR 24997 - FPL Energy Point Beach, LLC; Point Beach Nuclear Plant, Units 1 and 2; Environmental Assessment...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-06

    ..., ``Generic Environmental Impact Statement for License Renewal of Nuclear Plants [regarding Point Beach... environment. Accordingly, the NRC has determined not to prepare an environmental impact statement for the... From the Federal Register Online via the Government Publishing Office NUCLEAR...

  17. The Impacts of Back-Beach Barriers on Sandy Beach Morphology Along the California Coast and Implications for Coastal Change with Future Sea-Level Rise

    NASA Astrophysics Data System (ADS)

    Harden, E. L.

    2010-12-01

    Coastal squeeze, or foreshore narrowing, is a result of marine encroachment, such as sea-level rise in the presence of a back-beach barrier, terrestrial encroachment, such as coastal development, or both. In California, the permanent coastal population increased by almost 10 million people between 1980 and 2003, and an additional 130 million beachgoers visit Southern California beaches each year. Beaches in California are an important component of the state and federal economy and provide hundreds of thousands of jobs. Approximately 14% of the California coast from Marin County to the Mexican border is artificially armored with seawalls, rip rap, or revetment, more than half of which protects back-beach developments or lower-lying dynamic regions like harbors and dunes. Many sandy beaches that do not have back-beach armoring are still restricted by commercial and residential infrastructure, parking lots, and roadways. Although these types of coastal infrastructure are not back-beach barriers by intentional design like seawalls and rip rap, they still restrict beaches from landward migration and can cause significant placement loss of the beach. Nearly 67 km, or 44% of the total length of sandy coastline from Long Beach to the U.S.-Mexico border is backed by such infrastructure. This study is part of a broader effort to catalog the extent to which California’s beaches are restricted in the back beach, to describe the effects of back-beach barriers on sandy beach morphology, and to predict how these different beaches might behave with future sea-level rise. Beach morphology, shoreface characteristics, and historical rates of shoreline change were compared between select beaches with back-beach barriers and unrestricted beaches using 1997 LiDAR data and shoreline rates of change published in the U.S. Geological Survey’s National Assessment of Shoreline Change report. Although preliminary results of the morphological analysis show that there is no statistically significant difference in foreshore characteristics such as seasonal berm height and foreshore slope between the two types of beaches, beaches without back-beach barriers have more developed back dune systems and are significantly wider than adjacent restricted beaches, given that no extensive artificial beach nourishment has occurred. In regions such as Ventura and Imperial Beach, unrestricted beaches are 50-100% wider than adjacent beaches with back-beach barriers even with no significant differences in historical rates of shoreline change. Taking into account the nature of the back beach is just as crucial in predicting impacts of sea-level rise on beaches in California as considering inundation and retreat in the foreshore, and will be an important consideration for coastal managers in designing sea-level rise adaptation plans.

  18. Did life begin on the beach?

    PubMed

    Bywater, Robert P; Conde-Frieboes, Kilian

    2005-08-01

    Water is one of the prerequisites of life. Further requirements are the existence of a system of interacting organic molecules capable of capturing and converting the supply of external energy and elaborating the replicating function that is needed for propagation. None of this would be possible without the existence of some means of concentrating, selecting, and then containing these mutually interacting substances in proximity to one another, i.e., a primitive cell. Starting from this hypothesis we propose a model for the development of life on Earth. Our model embodies the following new features: (1) rapid cycles of catalysis and transport of material, (2) desegregation (separation by tidal action and degradation by catalysis) as well as segregation (by chromatography on tidal beaches), (3) cross-catalysis instead of auto-catalysis, as well as (4) compartmentalization, although the latter idea is of course not new. But our "lipid first" model, in contrast to earlier "peptide first" or "RNA first" models, provides for the compartments needed to act as a cradle for the subsequent development of information- rich molecules like peptides and RNA. If anything, the earliest information-rich molecules were probably membrane-spanning peptides/proteins. PMID:16078873

  19. What is on those Titan Beaches?

    NASA Astrophysics Data System (ADS)

    Beauchamp, P.; Cable, M.; Hodyss, R.; Choukroun, M.; Vu, T.; Malaska, M.

    2014-04-01

    Benzene is found on Titan and is a likely constituent of the putative evaporite deposits formed around the hydrocarbon lakes. We have recently demonstrated the formation of a benzene-ethane co-crystal under Titan-like surface condition as a function of temperature. We show that the formation process would reach completion under Titan surface conditions in ~18 hours, and that benzene precipitates from liquid ethane as the co-crystal. This suggests that evaporite basins rich in benzene may not contain just pure crystalline materials, but instead the beaches or basins may be replete with co-crystals of various forms. These new structures may influence evaporite characteristics, such as particle size and infrared spectral properties. This co-crystalline form of benzene with ethane represents a new class of materials for Titan's surface, analogous to hydrated minerals on Earth. This work is being extended to explore the interaction of benzene with methane and propane at Titan temperatures. We are also investigating other molecules such as acetylene and pyridine to determine if co-crystal formation can occur in these systems as well.

  20. Heart Rate and Motion Analysis by GPS in Beach Soccer

    PubMed Central

    Castellano, Julen; Casamichana, David

    2010-01-01

    Although beach soccer has become increasingly popular in recent years very little scientific research has been conducted into the sport. A pilot study was carried out with the aim of examining the physiological (heart rate) and physical (motion analysis) responses of beach soccer players during competitive matches. Ten players (age 25.5 ± 0.5 years; height 1.80 ± 0.08 m; weight 78.2 ± 5.6 kg.) were studied over five beach soccer matches. The physiological demands were analysed by measuring heart rate (HR) using telemetric devices, while the physical profile was evaluated by recording motion and speed by means of GPS devices. During competitive matches, players obtained a HRmean of 165.2 bpm (86.5% HRmax), with 59.3% of the time participating (TP) corresponding to values above 90% of the HRmax. The distance covered per minute of participation was 97.7 m, with 9.5% of this distance corresponding to high-intensity running and 2.5% to sprint; the work:rest ratio was 1.4:1 and the maximum speed 21.7 km·h-1. These results showed that beach soccer is an intermittent physical activity of greater intensity than other team games. It requires a major contribution from the anaerobic system as emphasis is placed on players making quick bursts of high-intensity activity separated by brief rest periods. Key points The distance covered per minute of play is around 100 m. Beach soccer is an intermittent sport with a work:rest ratio of 1.4:1. The playing surface in beach soccer is an important handicap to obtain maximum speeds. Beach soccer has a high physiological intensity, with more than half of the game is spent at intensities above 90 % of the HRmax. PMID:24149392

  1. Late Pleistocene raised beaches of coastal Estremadura, central Portugal

    NASA Astrophysics Data System (ADS)

    Benedetti, Michael M.; Haws, Jonathan A.; Funk, Caroline L.; Daniels, J. Michael; Hesp, Patrick A.; Bicho, Nuno F.; Minckley, Thomas A.; Ellwood, Brooks B.; Forman, Steven L.

    2009-12-01

    We present new stratigraphic, sedimentological, and chronological data for a suite of tectonically raised beaches dating to Marine Isotope Stages 5, 4, and 3 along the Estremadura coast of west-central Portugal. The beach deposits are found in association with ancient tidal channels and coastal dunes, pollen bearing mud and peat, and Middle Paleolithic archaeological sites that confirm occupation of the coastal zone by Neanderthal populations. The significance of these deposits is discussed in terms of the archaeological record, the tectonic and geomorphic evolution of the coast, and correlation with reconstructions of global climate and eustatic sea-level change. Direct correlation between the Estremadura beach sections is complicated by the tectonic complexity of the area and the age of the beach deposits (which are near or beyond the limit of radiocarbon dating). Evidence from multiple sites dated by AMS radiocarbon and optical luminescence methods suggests broad synchroneity in relative sea-level changes along this coast during Marine Isotope Stage 3. Two beach complexes with luminescence and radiocarbon age control date to about 35 ka and 42 ka, recording a rise in relative sea level around the time of Heinrich Event 4 at 39 ka. Depending on assumptions about eustatic sea level at the time they were deposited, we estimate that these beaches have been uplifted at rates of 0.4-4.3 mm yr -1 by the combined effects of tectonic, halokinetic, and isostatic processes. Uplift rates of 1-2 mm yr -1 are likely if the beaches represent sea level stands at roughly 40 m below modern, as suggested by recent eustatic sea level reconstructions. Evidence from coastal bluffs and the interior of the study area indicates extensive colluvial, fluvial, and aeolian sedimentation beginning around 31 ka and continuing into the Holocene. These geomorphic adjustments are related to concomitant changes in climate and sea level, providing context that improves our understanding of Late Pleistocene landscape change and human occupation on the western Iberian margin.

  2. Does temperature and oxygen affect duration of intramarsupial development and juvenile growth in the terrestrial isopod Porcellio scaber (Crustacea, Malacostraca)?

    PubMed Central

    Horváthová, Terézia; Antol, Andrzej; Czarnoleski, Marcin; Kramarz, Paulina; Bauchinger, Ulf; Labecka, Anna Maria; Kozłowski, Jan

    2015-01-01

    Abstract According to the temperature-size rule (TSR), ectotherms developing under cold conditions experience slower growth as juveniles but reach a larger size at maturity. Whether temperature alone causes this phenomenon is unknown, but oxygen limitation can play a role in the temperature-size relationship. Oxygen may become limited under warm conditions when the resulting higher metabolism creates a greater demand for oxygen, especially in larger individuals. We examined the independent effects of oxygen concentration (10% and 22% O2) and temperature (15 °C and 22 °C) on duration of ontogenic development, which takes place within the maternal brood pouch (marsupium), and juvenile growth in the terrestrial isopod common rough woodlouse (Porcellio scaber). Individuals inside the marsupium undergo the change from the aqueous to the gaseous environment. Under hypoxia, woodlice hatched from the marsupium sooner, but their subsequent growth was not affected by the level of oxygen. Marsupial development and juvenile growth were almost three times slower at low temperature, and marsupial development was longer in larger females but only in the cold treatment. These results show that temperature and oxygen are important ecological factors affecting developmental time and that the strength of the effect likely depends on the availability of oxygen in the environment. PMID:26261441

  3. Spectroscopic parameters of the cuticle and ethanol extracts of the fluorescent cave isopod Mesoniscus graniger (Isopoda, Oniscidea)

    PubMed Central

    Giurginca, Andrei; Šustr, Vladimír; Tajovský, Karel; Giurginca, Maria; Matei, Iulia

    2015-01-01

    Abstract The body surface of the terrestrial isopod Mesoniscus graniger (Frivaldsky, 1863) showed blue autofluorescence under UV light (330–385 nm), using epifluorescence microscopy and also in living individuals under a UV lamp with excitation light of 365 nm. Some morphological cuticular structures expressed a more intense autofluorescence than other body parts. For this reason, only the cuticle was analyzed. The parameters of autofluorescence were investigated using spectroscopic methods (molecular spectroscopy in infrared, ultraviolet-visible, fluorescence, and X-ray fluorescence spectroscopy) in samples of two subspecies of Mesoniscus graniger preserved in ethanol. Samples excited by UV light (from 350 to 380 nm) emitted blue light of wavelengths 419, 420, 441, 470 and 505 nm (solid phase) and 420, 435 and 463 (ethanol extract). The results showed that the autofluorescence observed from living individuals may be due to some β-carboline or coumarin derivatives, some crosslinking structures, dityrosine, or due to other compounds showing similar excitation-emission characteristics. PMID:26261444

  4. Long-term exposure of the isopod Porcellionides pruinosus to nickel: Costs in the energy budget and detoxification enzymes.

    PubMed

    Ferreira, Nuno G C; Cardoso, Diogo N; Morgado, Rui; Soares, Amadeu M V M; Loureiro, Susana

    2015-09-01

    Terrestrial isopods from the species Porcellionides pruinosus were exposed to the maximum allowed nickel concentration in the Canadian framework guideline (50 mg Ni/kg soil) and to 5× this concentration (250 mg Ni/kg soil). The exposure lasted for 28 days and was followed by a recovery period of 14 days where organisms were changed to clean soil. Organisms were sampled after 24 h, 48 h, 96 h, 7 days, 14 days, 21 days, and 28 days of exposure, and at days 35 and 42 during the recovery period. For each sampling time the acetylcholinesterase (AChE), glutathione-S-transferases (GST), catalase (CAT), lactate dehydrogenase (LDH) activities were determined as well as lipid peroxidation rate (LPO) along with lipids, carbohydrates, proteins content, energy available (Ea), energy consumption (Ec) and cellular energy allocation (CEA). The integrated biomarker response (IBR) was calculated for each sampling time as well as for each one of the above parameters. In addition, mortality was also recorded throughout the assay. The results obtained showed that nickel induced oxidative stress, evidenced by results on GST, GPx, CAT or LPO, but also on changes in the energy reserves content of these organisms. In addition, this study showed that these organisms possess a specific strategy to handle nickel toxicity. In this case, biomarkers were associated with costs in the energy budget, and the increase of energy reserves has a compensation for that cost. PMID:25985212

  5. Lack of taxonomic differentiation in an apparently widespread freshwater isopod morphotype (Phreatoicidea: Mesamphisopidae: Mesamphisopus) from South Africa.

    PubMed

    Gouws, Gavin; Stewart, Barbara A; Matthee, Conrad A

    2005-10-01

    The unambiguous identification of phreatoicidean isopods occurring in the mountainous southwestern region of South Africa is problematic, as the most recent key is based on morphological characters showing continuous variation among two species: Mesamphisopus abbreviatus and M. depressus. This study uses variation at 12 allozyme loci, phylogenetic analyses of 600 bp of a COI (cytochrome c oxidase subunit I) mtDNA fragment and morphometric comparisons to determine whether 15 populations are conspecific, and, if not, to elucidate their evolutionary relationships. Molecular evidence suggested that the most easterly population, collected from the Tsitsikamma Forest, was representative of a yet undescribed species. Patterns of differentiation and evolutionary relationships among the remaining populations were unrelated to geographic proximity or drainage system. Patterns of isolation by distance were also absent. An apparent disparity among the extent of genetic differentiation was also revealed by the two molecular marker sets. Mitochondrial sequence divergences among individuals were comparable to currently recognized intraspecific divergences. Surprisingly, nuclear markers revealed more extensive differentiation, more characteristic of interspecific divergences. This disparity and the mosaic pattern of differentiation may be driven by stochastic population crashes and genetic bottlenecks (caused by seasonal habitat fluctuations), coupled with genetic drift. PMID:16111899

  6. Ultrastructure and mineral composition of the cornea cuticle in the compound eyes of a supralittoral and a marine isopod.

    PubMed

    Alagboso, Francisca I; Reisecker, Christian; Hild, Sabine; Ziegler, Andreas

    2014-08-01

    The cuticle of the cornea in Crustacea is an interesting example of a composite material compromising between two distinct functions. As part of the dioptric apparatus of the ommatidia within the complex eye it forms transparent micro-lenses that should as well maintain the mechanical stability of the head capsule. We analyzed the ultrastructure and composition of the isopod cornea cuticle of the terrestrial species Ligia oceanica and the marine Sphaeroma serratum. We used a variety of tissue preparation methods, electron microscopic techniques as well as electron microprobe analysis and Raman spectroscopic imaging. The results reveal various structural adaptations that likely increase light transmission. These are an increase in the thickness of the epicuticle, a reduction of the thickness of the outer layer of calcite, a spatial restriction of pore canals to interommatidial regions, and, for S. serratum only, an increase in calcite crystal size. In both species protein-chitin fibrils within the proximal exocuticle form a peculiar reticular structure that does not occur within the cuticle of the head capsule. In L. oceanica differential mineralization results in a spherically shaped interface between mineralized and unmineralized endocuticle, likely an adaptation to increase the refractive power of the cornea maintaining the mechanical stability of the cuticle between the ommatidia. The results show that the habitat and differences in the general structure of the animal's cuticle affect the way in which the cornea is adapted to its optical function. PMID:24937761

  7. "Candidatus Bacilloplasma," a novel lineage of Mollicutes associated with the hindgut wall of the terrestrial isopod Porcellio scaber (Crustacea: Isopoda).

    PubMed

    Kostanjsek, Rok; Strus, Jasna; Avgustin, Gorazd

    2007-09-01

    Pointed, rod-shaped bacteria colonizing the cuticular surface of the hindgut of the terrestrial isopod crustacean Porcellio scaber (Crustacea: Isopoda) were investigated by comparative 16S rRNA gene sequence analysis and electron microscopy. The results of phylogenetic analysis, and the absence of a cell wall, affiliated these bacteria with the class Mollicutes, within which they represent a novel and deeply branched lineage, sharing less than 82.6% sequence similarity to known Mollicutes. The lineage has been positioned as a sister group to the clade comprising the Spiroplasma group, the Mycoplasma pneumoniae group, and the Mycoplasma hominis group. The specific signature sequence was identified and used as a probe in in situ hybridization, which confirmed that the retrieved sequences originate from the attached rod-shaped bacteria from the hindgut of P. scaber and made it possible to detect these bacteria in their natural environment. Scanning and transmission electron microscopy revealed a spherically shaped structure at the tapered end of the rod-shaped bacteria, enabling their specific and exclusive attachment to the tip of the cuticular spines on the inner surface of the gut. Specific adaptation to the gut environment, as well as phylogenetic positioning, indicate the long-term association and probable coevolution of the bacteria and the host. Taking into account their pointed, rod-shaped morphology and their phylogenetic position, the name "Candidatus Bacilloplasma" has been proposed for this new lineage of bacteria specifically associated with the gut surface of P. scaber. PMID:17630315

  8. Developmental changes in dopamine modulation of the heart in the isopod crustacean Ligia exotica: reversal of chronotropic effect.

    PubMed

    Yamagishi, Hiroshi; Miyamoto, Hiroshi; Sakurai, Akira

    2004-09-01

    Developmental changes in dopamine modulation of the heart were examined in the isopod crustacean Ligia exotica. The Ligia cardiac pacemaker is transferred from the myocardium to the cardiac ganglion during juvenile development and the heartbeat changes from myogenic to neurogenic. In the myogenic heart of early juveniles, dopamine affected the myocardium and caused a decrease in the frequency and an increase in the duration of the myocardial action potential, resulting in negative chronotropic (decrease in beat frequency) and positive inotropic (increase in contractile force) effects on the heart. Contrastingly, in the heart of immature adults just after juvenile development, dopamine caused effects of adult type, positive chronotropic and positive inotropic effects on the heart affecting the cardiac ganglion and myocardium. During the middle and late juvenile stages, dopamine caused individually a negative or a positive chronotropic effect on the heart. These results suggest that the chronotropic effect of dopamine on the Ligia heart is reversed from negative to positive in association with the cardiac pacemaker transfer from the myocardium to the cardiac ganglion during juvenile development. PMID:15459449

  9. Ultrastructure of the sinus gland and lateral cephalic nerve plexus in the isopod Ligia oceanica (Crustacea Oniscoidea).

    PubMed

    Martin, G; Maissiat, R; Girard, P

    1983-10-01

    Isopod crustaceans have two distinct cephalic neurohemal organs: the sinus gland (SG) and lateral cephalic nerve plexus (LCNP). The present study of Ligia oceanica was designed to ascertain the ultrastructure, during the moulting cycle, of the terminals constituting the SG and LCNP, both of which store and release neurosecretory material, and to trace these terminals to their probable origin in neurosecretory perikarya. The SG was observed to contain four types of terminals (I, II, III, and IV) assigned, on the basis of the appearance of their neurosecretory granules, to four types of neurosecretory cells in the protocerebrum (beta 1, beta 2, B1, and Bu). When the same morphological criteria were applied to the LCNP, two types of terminals were found--III' and IV'. Type III' was thought to originate in the Bp plexus cells and in the B2 cells of the suboesophageal ganglion. The origins of Type IV' terminals were believed to be the Bu and Bm cells of this ganglion. Release from both the GS and LCNP occurred by exocytosis. The discussion attempts to relate the ultrastructural variations observed in the SG and LCNP with existing data on the neuroendocrine regulation of the moult. Such regulation involves the two antagonistic hormones (moult-inhibiting and moult-accelerating) which determine the circulating ecdysteroid level. It is also suggested that the plexus cells are the site of synthesis of a factor controlling the release of the exuviation factor. PMID:6628977

  10. First record of Wolbachia in South American terrestrial isopods: Prevalence and diversity in two species of Balloniscus (Crustacea, Oniscidea)

    PubMed Central

    Almerão, Mauricio Pereira; Fagundes, Nelson Jurandi Rosa; de Araújo, Paula Beatriz; Verne, Sébastien; Grandjean, Frédéric; Bouchon, Didier; Araújo, Aldo Mellender

    2012-01-01

    Wolbachia are endosymbiotic bacteria that commonly infect arthropods, inducing certain phenotypes in their hosts. So far, no endemic South American species of terrestrial isopods have been investigated for Wolbachia infection. In this work, populations from two species of Balloniscus (B. sellowii and B. glaber) were studied through a diagnostic PCR assay. Fifteen new Wolbachia 16S rDNA sequences were detected. Wolbachia found in both species were generally specific to one population, and five populations hosted two different Wolbachia 16S rDNA sequences. Prevalence was higher in B. glaber than in B. sellowii, but uninfected populations could be found in both species. Wolbachia strains from B. sellowii had a higher genetic variation than those isolated from B. glaber. AMOVA analyses showed that most of the genetic variance was distributed among populations of each species rather than between species, and the phylogenetic analysis suggested that Wolbachia strains from Balloniscus cluster within Supergroup B, but do not form a single monophyletic clade, suggesting multiple infections for this group. Our results highlight the importance of studying Wolbachia prevalence and genetic diversity in Neotropical species and suggest that South American arthropods may harbor a great number of diverse strains, providing an interesting model to investigate the evolution of Wolbachia and its hosts. PMID:23413179

  11. Biology and life cycle of Natatolana borealis Lilj.1851, a scavenging isopod from the continental slope of the Mediterranean

    NASA Astrophysics Data System (ADS)

    Kaïm-Malka, R. A.

    1997-12-01

    The biology of Natatolana borealis, a deep-sea (-500 m) scavenging isopod that lives on the continental slope of Mediterranean canyons, was studied in the field and in the laboratory. Animals were collected at two stations using a baited trap. Whatever the site at which the animals were collected, a strong correlation was always found to exist between their length and weight, which shows variably marked seasonal variations. The growth pattern was modelled by fitting the Von Bertalanffy growth equation to the length of animals of various ages. The lifespan was estimated to be 6 years in the case of the largest animals collected. Sexual maturity is presumably reached at the age of 2.5 years. Not all the females were found to be sexually active at the same period of the year. A scheme of reproductive cycle is proposed for the mature females. It seems likely that each female may produce at least four broods during her lifetime. The emergence of offspring occurs at various times throughout the year, resulting in successive cohorts. At some periods in the year, some developmental stages were lacking in the samples, possibly owing to alimentary behaviour that helps to protect the animals from predators.

  12. Monitoring and modeling nearshore dredge disposal for indirect beach nourishment, Ocean Beach, San Francisco

    USGS Publications Warehouse

    Barnard, Patrick L.; Hanes, Daniel M.; Lescinski, Jamie; Elias, Edwin

    2007-01-01

    Nearshore dredge disposal was performed during the summer of 2005 at Ocean Beach, San Francisco, CA, a high energy tidal and wave environment. This trial run was an attempt to provide a buffer to a reach of coastline where wave attack during the winter months has had a severe impact on existing sewage infrastructure. Although the subsequent beach response was inconclusive, after one year the peak of the disposal mound had migrated ~100 m toward the shore, providing evidence that annual dredge disposal at this site could be beneficial over the long-term by at the very least providing: 1) additional wave dissipation during storms 2) compatible sediment to feed nearshore bars, 3) sediment cover on an exposed sewage outfall pipe, and 4) a viable alternative to the shoaling offshore disposal site. Numerical modeling suggests that despite the strong tidal currents in the region, wave forcing is the dominant factor moving the sediment slowly toward shore, and placing sediment at just slightly shallower depths (e.g. 9 m) in the future would have a more immediate impact.

  13. Swash Zone Sediment Dynamics on Steep and Shallow Beaches

    NASA Astrophysics Data System (ADS)

    Miles, J. R.; Butt, T.; Russell, P. E.; Masselink, G.; Evans, D.; Ganderton, P.; Huntley, D. A.

    2002-12-01

    In the swash zone, high sediment concentrations and large flow velocities mean that the potential for sediment transport and beach profile change is considerable. However, our understanding of the contribution of different suspension mechanisms (e.g. velocity, acceleration, turbulence, in/exfiltration) on beaches of different slopes is limited. Furthermore, the cross-shore structure of sediment transport in the swash zone is poorly understood. Field measurements of swash hydrodynamics, sediment dynamics and profile change have therefore been made at a dissipative, fine grained beach in North Cornwall, UK (Perranporth), and at a steeper, coarser grained beach in West Cornwall (Sennen). Velocities were measured at high frequency close to the bed using a vertical array of two electromagnetic current meters and 2-D and 3-D acoustic döppler velocimeters. Suspended sediment concentrations were measured using a vertical array of miniature optical backscatter sensors. Further to this, run-up data were collected using video, pressure sensors were used to measure wave heights and pressure gradients in the bed, and surveys were taken at each low tide to establish profile change. On both beaches, large suspended sediment concentrations (200kg/m3) were measured in the initial (turbulent) part of the uprush. On the dissipative beach, secondary waves behind the initial uprush suspended an order of magnitude less sediment than the initial front. On the steep beach, the high uprush concentrations in the inner swash were well correlated with downward pressure gradients in the bed, suggesting a dominance of boundary layer thinning over sediment stabilisation. During the backwash, a second peak in concentration occurred, although backwash velocities were not as efficient at suspending sediment than uprush velocities. The net cross-shore transport from uprush and backwash was examined in relation to cross-shore position in the swash. Data from high-energy conditions showed that on both beaches, onshore transport dominated in the inner swash zone on both flood and ebb tides. A zero crossing in the cross-shore transport occurred at the mid swash zone on the flood tide on both beaches. Offshore transport occurred seaward of this point. The transport divergence point shifted landward in both cases during the ebb tide, possibly due to differences in the water table. Further detailed analysis of data is being carried out in order to examine the role of the various mechanisms of suspension, and their contribution at different cross-shore positions in the swash.

  14. Macrofaunal sediment selectivity considerations for beach nourishment programmes.

    PubMed

    Van Tomme, J; Vanden Eede, S; Speybroeck, J; Degraer, S; Vincx, M

    2013-03-01

    Nowadays, beach nourishment is widely considered as a better alternative compared to the construction of hard structures to protect a sandy coast against detrimental erosive effects, both from an ecological and an engineering perspective. The rare studies conducted on the ecological impact of beach nourishment are short-term, post hoc monitoring investigations of the benthic macrofauna. Little is known of the biological processes during and after nourishment. To allow swift recolonization after nourishment, the characteristics of the nourished beach have to match the habitat demands of the benthic macrofauna. The sediment preference of the key intertidal species Scolelepis squamata, Eurydice pulchra, Bathyporeia pilosa and Bathyporeia sarsi, which dominate many West European sandy beaches, was investigated through laboratory experiments, both in single-species as well as combined-species treatments. While the former aimed at developing guidelines for impact mitigation of beach nourishment, the latter aimed at elucidating the role of biotic interactions in sediment preference. Results of the experiments indicated that B. pilosa and E. pulchra prefer the finest sediment, while B. sarsi had a broader preference and also occurred in medium-coarse sediments. However, the sediment preference of E. pulchra for fine sediments was not confirmed by other field and experimental studies. The polychaete S. squamata had the broadest preference and even showed a high occurrence in coarse sediments that are not naturally occurring on the sandy beaches where the animals were caught for this experiment. However, this polychaete is a cosmopolitan species, not only occurring on fine-grained beaches, but also on coarse-grained beaches worldwide. The preferences imply that beach nourishment with coarse sediment will have a major effect on B. pilosa while effects of coarse sediments on S. squamata will be minor. Finally, interspecific competition with the sympatrically occurring amphipod B. sarsi was found to change the sediment selection of the amphipod B. pilosa towards the coarser sediments where B. sarsi occurred in lower frequencies. PMID:23182894

  15. Low faunal diversity on Maltese sandy beaches: fact or artefact?

    NASA Astrophysics Data System (ADS)

    Deidun, Alan; Azzopardi, Marthese; Saliba, Stephen; Schembri, Patrick J.

    2003-10-01

    Eight sandy beaches on Malta and two on Gozo were sampled for macrofauna to test the hypothesis that Maltese beaches have an intrinsically low diversity. Stations distributed in the supralittoral (dry zone), mediolittoral (wet zone) and upper infralittoral (submerged zone to 1 m water depth) were sampled by sieving core samples and standardised searching during daytime, and pitfall trapping and standardised sweeping of the water column using a hand-net at night, as appropriate. Physical parameters of the sediment were measured and human occupancy of the beaches was estimated. From the supralittoral and mediolittoral, 39 species represented by 1584 individuals were collected by the combined techniques of pitfall trapping, sieving and standard searching. For Ramla beach, which had the highest diversity, 267 individuals representing 25 infaunal species were collected by sieving from a combined volume of 1.175 m 3 of sand, and 149 individuals representing 28 epifaunal species were collected by standardised searching from a combined area of 700 m 2 of sand during two winter and two summer sampling sessions between 1992 and 1993. For nine other beaches sampled during the summer of 2000, only six macrofaunal species were collected from core samples, with overall population densities ranging from 4.13 to 45.45 individuals m -2. Only 92 individuals belonging to 12 species were collected by hand-net from the uppermost infralittoral of five beaches sampled using this method during the summer of 2000. Taxa of gastropods, bivalves, decapods, mysids and staphylinid beetles generally abundant on Mediterranean sandy beaches, were entirely absent from the beaches sampled. Few correlations that could explain the impoverishment of Maltese sandy beaches were found between physical parameters and faunal abundances, and other factors such as inadequate sampling effort, human disturbance and marine pollution were also excluded; however, seasonally biased sampling may partly explain the results obtained. One factor that may explain why certain species are missing could be lack of recruitment, due to Malta's geographical isolation from the European and African mainlands.

  16. Water quality, weather and environmental factors associated with fecal indicator organism density in beach sand at two recreational marine beaches

    PubMed Central

    Heaney, Christopher D.; Exum, Natalie G.; Dufour, Alfred P.; Brenner, Kristen P.; Haugland, Richard A.; Chern, Eunice; Schwab, Kellogg J.; Love, David C.; Serre, Marc L.; Noble, Rachel; Wade, Timothy J.

    2015-01-01

    Recent studies showing an association between fecal indicator organisms (FIOs) in sand and gastrointestinal (GI) illness among beachgoers with sand contact have important public health implications because of the large numbers of people who recreate at beaches and engage in sand contact activities. Yet, factors that influence fecal pollution in beach sand remain unclear. During the 2007 National Epidemiological and Environmental Assessment of Recreational (NEEAR) Water Study, sand samples were collected at three locations (60 m apart) on weekend days (Sat, Sun) and holidays between June and September at two marine beaches — Fairhope Beach, AL and Goddard Beach, RI — with nearby publicly-owned treatment works (POTWs) outfalls. F+ coliphage, enterococci, Bacteroidales, fecal Bacteroides spp., and Clostridium spp. were measured in sand using culture and qPCR-based calibrator-cell equivalent methods. Water samples were also collected on the same days, times and transects as the 144 sand samples and were assayed using the same FIO measurements. Weather and environmental data were collected at the time of sample collection. Mean FIO concentrations in sand varied over time, but not space. Enterococci CFU and CCE densities in sand were not correlated, although other FIOs in sand were. The strongest correlation between FIO density in sand and water was fecal Bacteroides CCE, followed by enterococci CFU, Clostridium spp. CCE, and Bacteroidales CCE. Overall, the factors associated with FIO concentrations in sand were related to the sand–water interface (i.e., sand-wetting) and included daily average densities of FIOs in water, rainfall, and wave height. Targeted monitoring that focuses on daily trends of sand FIO variability, combined with information about specific water quality, weather, and environmental factors may inform beach monitoring and management decisions to reduce microbial burdens in beach sand. The views expressed in this paper are those of the authors and do not necessarily reflect the views or policies of the U.S. Environmental Protection Agency. PMID:25150738

  17. Water quality, weather and environmental factors associated with fecal indicator organism density in beach sand at two recreational marine beaches.

    PubMed

    Heaney, Christopher D; Exum, Natalie G; Dufour, Alfred P; Brenner, Kristen P; Haugland, Richard A; Chern, Eunice; Schwab, Kellogg J; Love, David C; Serre, Marc L; Noble, Rachel; Wade, Timothy J

    2014-11-01

    Recent studies showing an association between fecal indicator organisms (FIOs) in sand and gastrointestinal (GI) illness among beachgoers with sand contact have important public health implications because of the large numbers of people who recreate at beaches and engage in sand contact activities. Yet, factors that influence fecal pollution in beach sand remain unclear. During the 2007 National Epidemiological and Environmental Assessment of Recreational (NEEAR) Water Study, sand samples were collected at three locations (60 m apart) on weekend days (Sat, Sun) and holidays between June and September at two marine beaches - Fairhope Beach, AL and Goddard Beach, RI - with nearby publicly-owned treatment works (POTWs) outfalls. F(+) coliphage, enterococci, Bacteroidales, fecal Bacteroides spp., and Clostridium spp. were measured in sand using culture and qPCR-based calibrator-cell equivalent methods. Water samples were also collected on the same days, times and transects as the 144 sand samples and were assayed using the same FIO measurements. Weather and environmental data were collected at the time of sample collection. Mean FIO concentrations in sand varied over time, but not space. Enterococci CFU and CCE densities in sand were not correlated, although other FIOs in sand were. The strongest correlation between FIO density in sand and water was fecal Bacteroides CCE, followed by enterococci CFU, Clostridium spp. CCE, and Bacteroidales CCE. Overall, the factors associated with FIO concentrations in sand were related to the sand-water interface (i.e., sand-wetting) and included daily average densities of FIOs in water, rainfall, and wave height. Targeted monitoring that focuses on daily trends of sand FIO variability, combined with information about specific water quality, weather, and environmental factors may inform beach monitoring and management decisions to reduce microbial burdens in beach sand. The views expressed in this paper are those of the authors and do not necessarily reflect the views or policies of the U.S. Environmental Protection Agency. PMID:25150738

  18. Natural Reworking of Tsunami Evidence in Chandipur Beach, India

    NASA Astrophysics Data System (ADS)

    Ghosh, T.; Mukhopadhyay, A.

    2010-12-01

    In a particular tide- or wave- dominated environment the flow energy is best understood by the size of the sand grains deposited at the respective bar or beach or the depositional platform. Though the flow energy is generally fluctuating in this kind of dynamic environment, the overall set up can represent a particular domain of energy regime. A particular range of grain size is supposed to be deposited laterally and vertically as well. A specific trend of variation in grain size is also expected and can be estimated from both the hydrodynamic and aerodynamic interplay or in combination. Hence, whenever any stratum with an extra ordinary grain size is observed, that usually stimulates to think about some sudden and extraordinary energy regime, indicate a catastrophic event. In the year 2005, on Chandipur beach (Orissa, India) such a stratum found with an unusual grain size, which was much coarser than the usual grains¬ extended along the beach and outer flank of the main bar, exhibited many unusual features in its morphology and mineralogy indicated a possible deposit due to the great Indian Ocean tsunami of 2004. In the contrary, the same deposit is exhibiting the definite reworking due to the normal beach process in 2008. It’s a definite signature of gap of information in a dynamic environment and a challenge for the palaeo-tsunami researchers. Key words: Tsunami deposit; Beach dynamics; Natural reworking

  19. New beach ridge type: severely limited fetch, very shallow water

    SciTech Connect

    Tanner, W.F.; Demirpolat, S.

    1988-09-01

    The southern end of Laguna Madre (Texas) north of the Rio Grande mouth is marked by very shallow water, wide tidal flats, lunettes, islands made of beach ridges, and lesser features. The number and variety of islands in the lagoon is remarkable. The lunettes (clay dunes) are made primarily of quartz sand and coarse silt. They are common 5-10 m high, irregular in shape, and steep sided. They were deposited from wind transport and did not migrate. Those that are islands in the lagoon predate present position of sea level. Islands made of beach ridges were built from the lagoon side. Photoanalysis, field work, and granulometry all show that this sand was not moved into these ridges by Gulf of Mexico waves. Trenches in 12 beach ridges showed horizontal bedding but neither low-angle nor steep cross-bedding (quite unlike swash-built beach ridges). The ridges were built by wind-tide lag effects, not from the swash. Therefore, these beach ridges are a new type, in addition to swash-built, eolian, and storm-surge ridges. Growth of the ridges appears to be completed.

  20. History of monitoring beaches around Dounreay, and some future work.

    PubMed

    Toole, Joe

    2007-09-01

    Since the first finds of radioactive particles on beaches in north Caithness in the early 1980s, a programme of beach monitoring has been and continues to be undertaken by the United Kingdom Atomic Energy Authority, UKAEA. This programme has evolved over the years: gradually more intensive monitoring has been required by the site regulator, the Scottish Environmental Protection Agency (SEPA), while UKAEA have managed the deployment of increasingly more sophisticated radiation detection technology to meet or exceed regulatory expectations. This paper provides an overview of the beach monitoring programmes, and summarises how many particles have been detected, where they have been found, and how radioactive they are. The large number of in situ measurements typically recorded during surveys and the large areas of beach sands monitored are illustrated by reference to survey data acquired in the first half of 2005. Finally, the implications of the detection of a small particle at a large public beach some 23 km east of the Dounreay site are briefly discussed, as is the nature of some future work related to this environmental legacy. PMID:17768314

  1. Beach groin acts as barrier to longshore transport

    NASA Astrophysics Data System (ADS)

    1990-09-01

    The Bergen Avenue Groin in Harvey Cedars, N.J., a storm protection structure that confines alongshore-moving sediment to create wider beaches, has been found to act as a barrier to longshore sediment transport according to Michael S. Bruno, Stevens Institute of Technology, Hoboken, N.J. Using a wave transformation-shoreline evolution model, Bruno examined the effectiveness of an existing stone groin on a commercially and historically valuable beach. His findings were summarized at the 21st Union of Panamerican Engineers meeting hosted by the American Association of Engineering Societies held in Washington, D.C., August 19-24.Groins are low, narrow jetties made of timber, stone, concrete, or steel that extend roughly perpendicular to the shoreline. They are designed to protect the shore from erosion by currents, tides or waves, or to trap sand and littoral drift to build up or make a beach. The advantage of a groin is that it is a permanent solution to beach erosion, as opposed to the continuing process of beach replenishment required in nonstructural processes such as beachfills. This same permanence, however, is often the downfall of structural solutions because of the long-term deleterious consequences associated with such devices.

  2. Predicting 'very poor' beach water quality gradings using classification tree.

    PubMed

    Thoe, Wai; Choi, King Wah; Lee, Joseph Hun-Wei

    2016-02-01

    A beach water quality prediction system has been developed in Hong Kong using multiple linear regression (MLR) models. However, linear models are found to be weak at capturing the infrequent 'very poor' water quality occasions when Escherichia coli (E. coli) concentration exceeds 610 counts/100 mL. This study uses a classification tree to increase the accuracy in predicting the 'very poor' water quality events at three Hong Kong beaches affected either by non-point source or point source pollution. Binary-output classification trees (to predict whether E. coli concentration exceeds 610 counts/100 mL) are developed over the periods before and after the implementation of the Harbour Area Treatment Scheme, when systematic changes in water quality were observed. Results show that classification trees can capture more 'very poor' events in both periods when compared to the corresponding linear models, with an increase in correct positives by an average of 20%. Classification trees are also developed at two beaches to predict the four-category Beach Water Quality Indices. They perform worse than the binary tree and give excessive false alarms of 'very poor' events. Finally, a combined modelling approach using both MLR model and classification tree is proposed to enhance the beach water quality prediction system for Hong Kong. PMID:26837834

  3. Isopods of the genus Ligia as potential biomonitors of trace metals from the gulf of California and pacific coast of the Baja California peninsula.

    PubMed

    García-Hernández, Jaqueline; Hurtado, Luis A; Leyva-García, Germán; Güido-Moreno, Adrián; Aguilera-Márquez, Daniela; Mazzei, Veronica; Ferrante, Margherita

    2015-02-01

    Supralittoral and high intertidal coastal zones are exposed to pollution from both marine and terrestrial sources and undergo higher deposition rates than the subtidal zone. It is therefore important to identify organisms for this section of the coastal area that can be tolerant to contaminants. The aim of this study was to determine if supralittoral isopods of the genus Ligia can be used as biomonitors, since they are abundant and widely distributed. For this purpose, concentrations of trace elements were determined in Ligia isopods in toto from 26 locations across the Gulf of California and Pacific coast of the Baja California peninsula, which were collected during the summers of 2009 and 2010. The concentrations of trace elements followed the order of; Zn≥Cu>As>Cd>Pb>Hg. Elevated concentrations of copper (up to 1010 μg/g) were detected in Ligia from Santa Rosalía (SRo), a locality where industrial mining of copper has historically occurred. Industrial and municipal sewage discharges appear to have contributed to the high concentrations of zinc (326 μg/g) and lead (144 μg/g) found in organisms from Guaymas location. The high mercury concentration in organisms from Mazatlán (M) (2.01 μg/g) was associated with a thermoelectric plant. Natural sources of metals were also detected; coastal upwelling appears to be associated with high cadmium concentrations in Ligia from Punta Baja (PB) (256 μg/g) in the Pacific coast, whereas hydrothermal vents may have contributed to high concentrations of arsenic at Ensenada (E) (61 μg/g). Our results suggest that Ligia isopods reflect the natural and anthropogenic inputs of trace metals in the environment and could potentially be used as biomonitor organisms of the intertidal rocky shores of the Gulf of California and Pacific coast. PMID:25463869

  4. Pyrene metabolites in the hepatopancreas and gut of the isopod Porcellio scaber, a new biomarker for polycyclic aromatic hydrocarbon exposure in terrestrial ecosystems

    SciTech Connect

    Stroomberg, G.J.; Knecht, J.A. de; Ariese, F.; Gestel, C.A.M. Van; Velthorst, N.H.

    1999-10-01

    The object of this study was to investigate the formation of pyrene metabolites by the isopod Porcellio scaber as a possible tool in the environmental risk assessment of polycyclic aromatic hydrocarbon (PAH) exposure in terrestrial ecosystems. The formation of pyrene metabolites was studied after either pulse exposure to a single high dose, or prolonged exposure (14 d) to a lower dosage. Exposure studies were carried out with unlabeled or radiolabeled pyrene, ion pair chromatography was used for analysis, and reference conjugates were synthesized. The authors also measured pyrene metabolites in field-exposed animals, to explore their use as biomarkers of PAH exposure. Analysis of the hepatopancreas and gut of single isopods revealed the formation of five products, one of which was 1-hydroxypyrene. Four of the remaining products were identified as phase 2 metabolites of 1-hydroxypyrene, with UV absorption and fluorescence characteristics similar to that of pyrene. One metabolite was identified as pyrene-1-glucoside, which is in accordance with high rates of glucosidation, reported for these isopods. Another conjugate was identified as pyrene-1-sulfate. None of the metabolites coeluted with a pyrene-1-glucuronide reference obtained from fish bile. A fifth metabolite detected by on-line scintillation detection did not exhibit any absorption at 340 nm, possibly because one of the aromatic rings of pyrene had lost its aromatic character. Although pyrene is not known for its toxicity, it usually co-occurs with other PAHs that are transformed into toxic products. Investigating the metabolism of pyrene can provide information with regard to the biotransformation capacity of invertebrate species and uptake and elimination kinetics. Because pyrene is one of the most predominant PAHs in the environment, analysis of its metabolites provides an extra tool for the environmental risk assessment of ecosystems with regard to PAH exposure, bioavailability, and biotransformation.

  5. Observations on the Activity and Life History of the Scavenging Isopod Natatolana borealisLilljeborg (Isopoda: Cirolanidae) from Loch Fyne, Scotland

    NASA Astrophysics Data System (ADS)

    Wong, Y. M.; Moore, P. G.

    1996-02-01

    The activity and life history of the cirolanid isopod Natatolana borealisLilljeborg has been studied using (primarily) fish-baited traps deployed at a deep-water station (190 m) in Loch Fyne, Scotland. A voracious scavenger, it burrows into soft mud, emerging to feed when suitable food odours are detected in the water. Isopods were attracted significantly to baited vs. non-baited traps. Underwater video observations revealed that most animals were active in the vicinity of traps, that capture efficiency was low, but retention complete. Only traps on the sea-bed captured mancas or juveniles in any numbers. Any seasonal pattern in catch rate through the year was confounded by high variability. Only one (manca-)brooding female was ever caught in a trap (in April). It is assumed that brooding females desist from feeding. The sex ratio of isopods in most trap collections was thus significantly male dominated. Mancas were trapped during February to August. Growth rate was slowest in adults and was similar for males and females. The maximum growth rate occurred during autumn associated with the seasonal cycle in bottom water temperatures. Longevity was estimated (by following peaks in the size-frequency distributions with time) to be c. 2·5 years, with sexual maturity (based on oostegites/spurred appendix masculinae) achieved after c. 19 months. Semelparity is suggested. A low incidence of an unnamed epicaridean parasite is reported from the Clyde population. Natatolana borealisalso carried peritrich ciliate epizoites on their antennae. Possible predators are swimming crabs and gadid fish, e.g. whiting and cod.

  6. Size at the onset of maturity (SOM) revealed in length-weight relationships of brackish amphipods and isopods: An information theory approach

    NASA Astrophysics Data System (ADS)

    Longo, Emanuela; Mancinelli, Giorgio

    2014-01-01

    In amphipods and other small-sized crustaceans, allometric relationships are conventionally analysed by fitting the standard model Y = a·Xb (X and Y are, e.g., body length and weight, respectively) whose scaling exponent b is assumed to be constant. However, breakpoints in allometric relationships have long been documented in large-sized crustaceans, ultimately determined by ontogenetic, abrupt variations in the value of b. Here, the existence of breakpoints in length-weight relationships was investigated in four amphipod (i.e., Gammarus aequicauda, Gammarus insensibilis, Microdeutopus gryllotalpa, and Dexamine spinosa) and three isopod species (i.e., Lekanesphaera hookeri, Sphaeroma serratum, and Cymodoce truncata) from three Mediterranean lagoons. The power of two candidate linear models fitted to log10-transformed data - a simple model assuming a constant exponent b and a segmented model assuming b to vary after a breakpoint - was compared using a parsimonious selection strategy based on the Akaike information criterion. The segmented model with a breakpoint provided the most accurate fitting of length-weight data in the majority of the species analysed; non-conclusive results were obtained only for D. spinosa and C. truncata, of which a limited number of specimens was examined. Model parameters were consistent for amphipod and isopod species collected across the three different habitats; the generality of the results was further supported by a literature search confirming that the identified breakpoints corresponded with ontogenetic discontinuities related with sexual maturation in all the species investigated. In this study, segmented regression models were revealed to provide a statistically accurate and biologically meaningful description of length-weight relationships of common amphipod and isopod species. The methodological limitations of the approach are considered, while the practical implications for secondary production estimates are discussed.

  7. Wave energy level and geographic setting correlate with Florida beach water quality.

    PubMed

    Feng, Zhixuan; Reniers, Ad; Haus, Brian K; Solo-Gabriele, Helena M; Kelly, Elizabeth A

    2016-03-15

    Many recreational beaches suffer from elevated levels of microorganisms, resulting in beach advisories and closures due to lack of compliance with Environmental Protection Agency guidelines. We conducted the first statewide beach water quality assessment by analyzing decadal records of fecal indicator bacteria (enterococci and fecal coliform) levels at 262 Florida beaches. The objectives were to depict synoptic patterns of beach water quality exceedance along the entire Florida shoreline and to evaluate their relationships with wave condition and geographic location. Percent exceedances based on enterococci and fecal coliform were negatively correlated with both long-term mean wave energy and beach slope. Also, Gulf of Mexico beaches exceeded the thresholds significantly more than Atlantic Ocean ones, perhaps partially due to the lower wave energy. A possible linkage between wave energy level and water quality is beach sand, a pervasive nonpoint source that tends to harbor more bacteria in the low-wave-energy environment. PMID:26892203

  8. Health effects associated with cyanobacteria exposure among beach attendees in Puerto Rico

    EPA Science Inventory

    Cyanobacteria and their toxins are associated with adverse human health effects, although among marine waters, the pyrrhophyta, including dinoflagellates are more recognized as health hazards. We recruited beach attendees during summer 2009, at Boquerón Beach, Puerto Rico...

  9. Recreational water exposures and health effects at a tropical and a runoff impacted beach

    EPA Science Inventory

    Background: Studies conducted by the EPA at beaches with nearby treated sewage discharges established associations between gastrointestinal (GI) illnesses among swimmers and measurements of fecal indicator bacteria, Enterococcus and Bacteroidales (marine beaches only) measured by...

  10. Health effects associated with cyanobacteria exposure among beach attendees in Puerto Rico

    EPA Science Inventory

    Cyanobacteria and their toxins are associated with adverse human health effects, although among marine waters, the pyrrhophyta, including dinoflagellates are more recognized as health hazards. We recruited beach attendees during summer 2009, at Boquerón Beach, Puerto Rico...

  11. The EMPACT Beaches Project Results from a Study on Microbiological Monitoring in Recreational Waters

    EPA Science Inventory

    The EMPACT (Environmental Monitoring for Public Access and Community Tracking) Beaches project has attempted to define which characteristics are most signifi cant with regard to monitoring approaches. This project examined five beach environments to determine the factors that mos...

  12. A method for determining average beach slope and beach slope variability for U.S. sandy coastlines

    USGS Publications Warehouse

    Doran, Kara S.; Long, Joseph W.; Overbeck, Jacquelyn R.

    2015-01-01

    The U.S. Geological Survey (USGS) National Assessment of Hurricane-Induced Coastal Erosion Hazards compares measurements of beach morphology with storm-induced total water levels to produce forecasts of coastal change for storms impacting the Gulf of Mexico and Atlantic coastlines of the United States. The wave-induced water level component (wave setup and swash) is estimated by using modeled offshore wave height and period and measured beach slope (from dune toe to shoreline) through the empirical parameterization of Stockdon and others (2006). Spatial and temporal variability in beach slope leads to corresponding variability in predicted wave setup and swash. For instance, seasonal and storm-induced changes in beach slope can lead to differences on the order of 1 meter (m) in wave-induced water level elevation, making accurate specification of this parameter and its associated uncertainty essential to skillful forecasts of coastal change. A method for calculating spatially and temporally averaged beach slopes is presented here along with a method for determining total uncertainty for each 200-m alongshore section of coastline.

  13. Industrial plastic on the southern beaches of the Arabian Gulf and the western beaches of the Gulf of Oman.

    PubMed

    Khordagui, H K; Abu-Hilal, A H

    1994-01-01

    The increasing production and use of plastic in the Arabian Gulf combined with shipping and waste disposal practices, have increased the concentration of plastic particles on the sea's surface and beaches. The objective of this investigation was to provide an assessment of the abundance, distribution, potential sources and significance of industrial plastic on the western beaches of the United Arab Emirates on the Arabian Gulf and on the eastern beaches on the Gulf of Oman. The abundance of stranded plastic pellets was highly uneven. By early 1992 alarming levels of fresh plastic pellets were noticed on the Arabian Gulf beaches of the UAE. Large numbers of 25 kg sacks of white plastic spherules manufactured by (SABIC) in Jubail, Saudi Arabia were washed ashore. When compared to the west coast on the Arabian Gulf, the east coast on the Gulf of Oman exhibited much lower levels of plastic pellets. When compared to other parts of the world, the beaches of the UAE on the Arabian Gulf are considered to be heavily polluted with industrial plastic. PMID:15091703

  14. Macrobenthic zonation patterns along a morphodynamical continuum of macrotidal, low tide bar/rip and ultra-dissipative sandy beaches

    NASA Astrophysics Data System (ADS)

    Degraer, S.; Volckaert, A.; Vincx, M.

    2003-03-01

    The species composition, densities, biomass and zonation patterns of the macrobenthos of sandy beaches are greatly influenced by the morphodynamics and morphology of the beaches. Macrobenthic zonation patterns along a small-scale morphodynamic gradient, comprising eight Belgian beach sites, were investigated. By taking into account the dimensionless fall velocity ( ?) and the relative tidal range, the beach sites were ordered along the gradient from the ultra-dissipative beach type (UD) to the low tide bar/rip beach type (LTBR). The resulting beach state index varied between 1.8 and 4.2 and the beach profiles were related with the beaches' morphodynamic state. In total 35 macrobenthic species, mainly polychaetes and crustaceans, were encountered, varying between 19 and 23 species per beach site. The species composition was quite similar among beach sites, with Scolelepis squamata being abundant at all eight sites. Furthermore, the macrobenthic distribution patterns were mainly related to elevation at all beach sites. Some remarkable difference in metrics, largely related to the beach morphodynamics and the consequent hydrodynamics, were found. At the hydrodynamically benign and consequently macrobenthos-rich UD beaches, the highest macrobenthic densities and biomass occurred on the upper beach, while at the hydrodynamically harsh and thus macrobenthos-poor LTBR beaches, the maximum densities and biomass occurred lower on the beach. Species, typically occurring on the upper UD beaches, such as Eurydice pulchra, S. squamata, and Bathyporeia sarsi, were restricted to the sub-optimal middle and lower beach zone at LTBR beaches. Only Bathyporeia pilosa was found on the upper beach of both UD and LTBR beaches. The more robust polychaete Ophelia rathkei and the interstitial polychaete Hesionides arenaria were exclusively found in the hydrodynamically harsh conditions of the middle LTBR beach zone.

  15. External costs of coastal beach pollution: an hedonic approach

    SciTech Connect

    Wilman, E.A.

    1984-01-01

    A technique for inputing a monetary value to the loss in beach recreational services that would result from a hypothetical oil spill in the Georges Bank area combines an oil-spill risk analysis model with a hedonic pricing model of the market for tourist accommodations on Cape Cod and Martha's Vineyard. The estimate of beach pollution costs associated with offshore oil development allows a rational judgment of whether the benefits of developing offshore oil outweigh the costs. The method is an effort to improve the economic efficiency of coastal zone management. The report concludes with a discussion of the many sources of uncertainty and suggestions for overcoming them. Five appendices present information on the models, variables, questionnaire responses, beaches, and factor patterns. 7 figures, 27 tables.

  16. The Effect of Temperature on Synchronization of Brood Development of the Bopyrid Isopod Parasite Probopyrus pandalicola with Molting of Its Host, the Daggerblade Grass Shrimp Palaemonetes pugio.

    PubMed

    Brinton, Brigette A; Curran, Mary Carla

    2015-08-01

    The bopyrid isopod Probopyrus pandalicola is a hematophagous ectoparasite that sexually sterilizes some palaemonid shrimps, including female daggerblade grass shrimp Palaemonetes pugio. The reproduction of parasitic isopods is thought to occur synchronously with host molting because the brood would be unsuccessful if molting occurred before the larvae were free swimming. Temperature affects the length of the molting cycle of shrimp, and therefore may also affect the incubation time of isopod broods. The purpose of the present study was to determine the effect of temperature on brood development of the parasite and on the degree of synchronization with the molting of its host. Parasitized P. pugio were monitored daily at 2 experimental temperatures, 23 and 15 C, in temperature-controlled chambers for the duration of a full parasite reproductive cycle. Developmental stage was determined by the visible coloration of the brood through the exoskeleton of the host, and was designated as egg, embryo I, embryo II, or epicaridium larvae. Temperature significantly affected median brood incubation time, which was only 11 days at 23 C, as compared to 35 days at 15 C. The final developmental stage (epicaridium larvae) was 3 times shorter at 23 C (median 3 days; n = 45) than at 15 C (median 9 days; n = 15). Temperature significantly affected the intermolt period of parasitized shrimp, which was shorter at 23 C (median 12 days) than at 15 C (median 37 days). A smaller percentage of the intermolt period elapsed between larval release and shrimp molting at 23 C (0.0%) than at 15 C (3.1%), indicating closer synchronization between host molting and parasite reproduction at the warmer temperature. At 15 C, the isopods utilized a smaller proportion of the time that was available for brood incubation during the intermolt period of their host. Brood size ranged from 391 to 4,596 young and was positively correlated with parasite and host size. Because development progressed more rapidly at 23 C, warmer temperatures could increase the prevalence of P. pandalicola. The corresponding reduction in the abundance of ovigerous grass shrimp as a result of sexual sterilization by bopyrids could adversely impact estuarine ecosystems, as grass shrimp are a crucial link in transferring energy from detritus to secondary consumers. PMID:25826017

  17. Mitochondrial DNA evidence for deep genetic divergences in allopatric populations of the rocky intertidal isopod Ligia occidentalis from the eastern Pacific.

    PubMed

    Markow, Therese A; Pfeiler, Edward

    2010-07-01

    Nucleotide sequences from the cytochrome c oxidase subunit I (COI) gene were used to test for genetic differentiation in the rocky intertidal isopod crustacean, Ligia occidentalis (Ligiidae), from the eastern Pacific. Phylogenetic analyses showed that individuals of L. occidentalis from southern California, USA to Manzanillo, Colima, Mexico partitioned into 15 highly-divergent clades. Mean Kimura 2-parameter (K2P) genetic distances among clades ranged from 13.2% to 26.7%. These values are similar to interspecific genetic distances found in a wide variety of crustaceans, including Ligia spp., suggesting that the taxon L. occidentalis represents a complex of cryptic species. PMID:20006723

  18. Equilibrium shoreline response of a high wave energy beach

    NASA Astrophysics Data System (ADS)

    Yates, M. L.; Guza, R. T.; O'Reilly, W. C.; Hansen, J. E.; Barnard, P. L.

    2011-04-01

    Four years of beach elevation surveys at Ocean Beach, San Francisco, California, are used to extend an existing equilibrium shoreline change model, previously calibrated with fine sand and moderate energy waves, to medium sand and higher-energy waves. The shoreline, characterized as the cross-shore location of the mean high water contour, varied seasonally by between 30 and 60 m, depending on the alongshore location. The equilibrium shoreline change model relates the rate of horizontal shoreline displacement to the hourly wave energy E and the wave energy disequilibrium, the difference between E and the equilibrium wave energy that would cause no change in the present shoreline location. Values for the model shoreline response coefficients are tuned to fit the observations in 500 m alongshore segments and averaged over segments where the model has good skill and the estimated effects of neglected alongshore sediment transport are relatively small. Using these representative response coefficients for 0.3 mm sand from Ocean Beach and driving the model with much lower-energy winter waves observed at San Onofre Beach (also 0.3 mm sand) in southern California, qualitatively reproduces the small seasonal shoreline fluctuations at San Onofre. This consistency suggests that the shoreline model response coefficients depend on grain size and may be constant, and thus transportable, between sites with similar grain size and different wave climates. The calibrated model response coefficients predict that for equal fluctuations in wave energy, changes in shoreline location on a medium-grained (0.3 mm) beach are much smaller than on a previously studied fine-grained (0.2 mm) beach.

  19. Equilibrium shoreline response of a high wave energy beach

    USGS Publications Warehouse

    Yates, M.L.; Guza, R.T.; O'Reilly, W. C.; Hansen, J.E.; Barnard, P.L.

    2011-01-01

    Four years of beach elevation surveys at Ocean Beach, San Francisco, California, are used to extend an existing equilibrium shoreline change model, previously calibrated with fine sand and moderate energy waves, to medium sand and higher-energy waves. The shoreline, characterized as the cross-shore location of the mean high water contour, varied seasonally by between 30 and 60 m, depending on the alongshore location. The equilibrium shoreline change model relates the rate of horizontal shoreline displacement to the hourly wave energy E and the wave energy disequilibrium, the difference between E and the equilibrium wave energy that would cause no change in the present shoreline location. Values for the model shoreline response coefficients are tuned to fit the observations in 500 m alongshore segments and averaged over segments where the model has good skill and the estimated effects of neglected alongshore sediment transport are relatively small. Using these representative response coefficients for 0.3 mm sand from Ocean Beach and driving the model with much lower-energy winter waves observed at San Onofre Beach (also 0.3 mm sand) in southern California, qualitatively reproduces the small seasonal shoreline fluctuations at San Onofre. This consistency suggests that the shoreline model response coefficients depend on grain size and may be constant, and thus transportable, between sites with similar grain size and different wave climates. The calibrated model response coefficients predict that for equal fluctuations in wave energy, changes in shoreline location on a medium-grained (0.3 mm) beach are much smaller than on a previously studied fine-grained (0.2 mm) beach. Copyright ?? 2011 by the American Geophysical Union.

  20. Beach and dunal system monitoring at Su Giudeu beach, Sardinia (Italy)

    NASA Astrophysics Data System (ADS)

    Balzano, Andrea; Sulis, Andrea

    2014-05-01

    Even if coastal floods are quite rare events in Sardinia (Italy) at present, they have had dramatic consequences for coastal communities, particularly in conjunction with river flooding. However, flood risk (defined as the product of event probability, vulnerability and value of assets) is expected to increase significantly in the future, due to climate change, defence degradation and sea level rise. Sardinia island has a costal length of approximately 1.900 km including minor neighbouring islands (25% of the entire Italian coasts) and the estimation of the potential exposure of coastal communities to flooding is therefore a critical task. To date methods for achieving this have been based on modelling of coastal inundation using hydrodynamic or GIS-based models of varying complexity. The Dept of Civil and Environmental Engineering and Architecture at the University of Cagliari is carrying out a comprehensive activity of coastal flooding risk mapping at the regional scale within the framework of a scientific collaboration with the Sardinian Regional Authority for the Hydrographic District, that includes monitoring and scientific activities along the entire Sardinian coast. Bathymetry and topographical surveys, sediment characterization, waves and currents measurements, hydrodynamic and morphodynamic modelling are planned, focusing on critical extended areas. In this paper we present an overview of the entire activity programme and give an in-depth account of the ongoing monitoring survey of the dunal system of the Su Giudeu beach (Southern Sardinia, 50 km far from the city of Cagliari). Su Giudeu is a sandy, bay-shaped beach, extending for about 1200 m between two headlands, evolving under waves with a predominant direction of 220-240°N (Scirocco wind). The survey is expected to provide evidence of the response of the remarkable dunal system to wave runup occurring during storm events, to be used in the verification of existing numerical models of dune erosion.

  1. Swash zone characteristics at Ocean Beach, San Francisco, CA

    USGS Publications Warehouse

    Erikson, L.H.; Hanes, D.M.; Barnard, P.L.; Gibbs, A.E.

    2007-01-01

    Runup data collected during the summer of 2005 at Ocean Beach, San Francisco, CA are analyzed and considered to be typical summer swash characteristics at this site. Analysis shows that the beach was dissipative with Iribarren numbers between 0.05 and 0.4 and that infragravity energy dominated. Foreshore slopes were mild between 0.01 and 0.05 with swash periods on the order of a minute. Predicted runup heights obtained with six previously developed analytical runup formulae were compared to measured extreme runup statistics. Formulations dependent on offshore wave height, foreshore slope and deep water wavelength gave reasonable results.

  2. 78 FR 25383 - Amendment of Class E Airspace; West Palm Beach, FL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-01

    ... Airspace in the West Palm Beach, FL area, as new Standard Instrument Approach Procedures (SIAPs) have been... area. This action also updates the geographic coordinates of the airport. DATES: Effective 0901 UTC... Beach County Park Airport, West Palm Beach, FL (78 FR 6258). Interested parties were invited...

  3. 75 FR 65581 - Proposed Amendment and Revocation of Class E Airspace, Vero Beach, FL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-26

    ... surface area at Vero Beach Municipal Airport, Vero Beach, FL. The Vero Beach Non- Directional Beacon (NDB... Federal Regulations (14 CFR) part 71 to amend Class E airspace designated as surface area to remove any... to Class D surface area to eliminate controlled airspace not required for the new SIAPs developed...

  4. 75 FR 52549 - Environmental Impact Statement; Alabama Beach Mouse Draft General Conservation Plan; Fort Morgan...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-26

    ... Fish and Wildlife Service Environmental Impact Statement; Alabama Beach Mouse Draft General... Beach Mouse General Conservation Plan (ABM GCP) Project. We are preparing the ABM GCP under the... are included in the plan: Alabama beach mouse (ABM) (Peromyscus polionotus ammobates), Loggerhead...

  5. 76 FR 48879 - Draft Environmental Impact Statement for Alabama Beach Mouse General Conservation Plan for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-09

    ... Fish and Wildlife Service Draft Environmental Impact Statement for Alabama Beach Mouse General... endangered Alabama beach mouse (Peromyscus polionotus ammobates) in Baldwin County, Alabama. The GCP analyzes... availability of the proposed GCP and the dEIS. These documents analyze the take of the Alabama beach...

  6. GREAT LAKES BEACH CLOSURES: USING SATELLITE IMAGES TO IDENTIFY AREAS AT RISK

    EPA Science Inventory

    Are people getting sick from swimming at Great Lakes beaches? Some are. According to the Centers for Disease Control and Prevention, swimmers are experiencing an increase in bacterial borne illnesses from swimming at many popular Great Lakes beaches. The beaches in the Great Lak...

  7. 75 FR 52461 - Drawbridge Operation Regulation; Atlantic Intracoastal Waterway, Wrightsville Beach, NC and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-26

    ..., Wrightsville Beach, NC and Northeast Cape Fear River, Wilmington, NC AGENCY: Coast Guard, DHS. ACTION: Notice..., mile 283.1, at Wrightsville Beach, NC, and the Isabel S. Holmes Bridge across the Northeast Cape Fear... 283.1, at Wrightsville Beach and the Isabel S. Holmes Bridge across the Northeast Cape Fear...

  8. 76 FR 16297 - Drawbridge Operation Regulation; Cerritos Channel, Long Beach, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-23

    ... SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulation; Cerritos Channel, Long Beach, CA... of the Commodore Schuyler F. Heim Drawbridge across Cerritos Channel, mile 4.9, at Long Beach, CA... Channel, at Long Beach, CA. The drawbridge navigation span provides a vertical clearance of 37 feet...

  9. 78 FR 39599 - Safety Zone; Independence Day Fireworks, Kings Beach, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-02

    ... SECURITY Coast Guard 33 CFR Part 165 Safety Zone; Independence Day Fireworks, Kings Beach, CA AGENCY: Coast... safety zone for the Independence Day Fireworks, Kings Beach, CA in the Captain of the Port, San Francisco... Marina to the launch site off of Kings Beach, CA in approximate position 39 13'55'' N, 120 01'42'' W...

  10. 77 FR 27624 - Drawbridge Operation Regulation; Cerritos Channel, Long Beach, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-11

    ... SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulation; Cerritos Channel, Long Beach, CA.... Heim Drawbridge across Cerritos Channel, mile 4.9, at Long Beach, CA. The deviation is necessary to... Drawbridge, mile 4.9, over Cerritos Channel, at Long Beach, CA. The drawbridge navigation span provides...

  11. Biomarkers and energy reserves in the isopod Porcellionides pruinosus: the effects of long-term exposure to dimethoate.

    PubMed

    Ferreira, Nuno G C; Morgado, Rui; Santos, Miguel J G; Soares, Amadeu M V M; Loureiro, Susana

    2015-01-01

    Terrestrial isopods from the species Porcellionides pruinosus were exposed to the recommended field dose application (0.4 mg/kg soil) and a sublethal concentration (10mg/kg soil) of dimethoate at two temperatures that can be generally found in several countries (20°C and 25°C) and are commonly used as reference temperatures. The organisms were exposed for 28 days and sampled at the following time points: 24h, 48 h, 96 h, 7 days, 14 days, 21 days, 28 days; organisms were then changed to clean soil for a recovery period of 14 days during which organisms were sampled on day 35 and 42. For each sampling time, the enzyme activities of acetylcholinesterase (AChE), glutathione-S-transferases (GST), catalase (CAT), lactate dehydrogenase (LDH) were determined as well as the following: total lipid, carbohydrate and protein content; energy available (Ea); energy consumption (Ec); cellular energy allocation (CEA) and lipid peroxidation rate (LPO). The integrated biomarker response (IBR) was calculated for each sampling time and for each of the above parameters. Mortality was also recorded during the study. The results obtained showed that dimethoate causes toxicity by several mechanisms. This study found evidence for the inhibition of the acetylcholinesterase enzyme, which has been previously reported, and also evidence of oxidative stress, which altered the levels of GST, CAT or LPO. In addition, the study showed that the two concentrations used of dimethoate caused the activation of different general detoxification mechanisms, and also that the same concentration at different temperatures induced different toxicity responses. PMID:25241210

  12. Distribution, life cycle and demography in a brackish water population of the isopod Cyathura carinata (Kröyer) (Crustacea)

    NASA Astrophysics Data System (ADS)

    Ólafsson, Einar B.; Persson, Lars-Eric

    1986-11-01

    Cyathura carinata, an infaunal, fossorial, isopod is a dominant member of a brackish, shallow water macrobenthic community on the south coast of Sweden. It has a bi-annual life-cycle. Breeding occurs in June-July, and a single brood of between 18-63 eggs per female is produced. The eggs take about 3-4 weeks to develop, the juveniles emerge in mid-late July. Initial recruitment in the study area was estimated to be 1480-1850 juveniles m -2 for 1981-1983 year classes. About 5% of the recruits survive to reproductive age two years later. Growth was characterized by fast growth during summer-autumn, stagnation in winter, and a slow start in spring. Females and males were not separated until just prior to reproduction (i.e. in June of the second year). At this stage males were larger than females and sex ratio was 1:1. During the breeding season, the abundance of males decreased rapidly due to post-reproductive death. Females continued to live, carrying the developing eggs in their brood pouches. Adult females die shortly after the young are released. The entire generation of reproductive adults (two years of age) has died by mid August. No evidence of the stated protogynous hermaphroditism was found in our study. Cohort production was 1·83 g wet wt m -2 for the 1980 cohort and 1·33 for the 1981 cohort. P/B-ratios were 2·12 for the 1980 cohort and 2·48 for the 1981 cohort. The P/B-ratios found were closest to those calculated by the method of Waters when an accurate estimate of mortality was available.

  13. Sexual sterilization of the daggerblade grass shrimp Palaemonetes pugio (Decapoda: Palaemonidae) by the bopyrid isopod Probopyrus pandalicola (Isopoda: Bopyridae).

    PubMed

    Sherman, Michele B; Curran, Mary Carla

    2015-02-01

    Probopyrus pandalicola is a bopyrid isopod that infects several palaemonid shrimp species, including the daggerblade grass shrimp Palaemonetes pugio . The parasite can have several negative effects on its host, including loss of hemolymph, reduced reproductive potential, and decreased molting frequency and growth. To date, there are conflicting reports on whether Probopyrus pandalicola affects the reproductive capability of both male and female daggerblade grass shrimp. The purpose of this study was to determine whether infection by Probopyrus pandalicola resulted in the sexual sterilization of Palaemonetes pugio , and if the reproductive capability of male and/or female shrimp was restored after the bopyrid was removed. We found that parasitized and deparasitized males were able to fertilize the eggs of unparasitized females successfully, as 18.9 ± 7.1% and 42.7 ± 5.2% of the females paired with them became ovigerous in 4 wk, respectively. Neither parasitized nor deparasitized females became ovigerous when placed with unparasitized males during the 4-wk period. However, 45.4 ± 20.6% of deparasitized females did become ovigerous within 10 wk. Despite the fact that female shrimp are able to reproduce again when no longer parasitized, the majority of females remain infected with the bopyrid for their entire lives. Therefore, the sexual sterilization of female shrimp could potentially have a significant impact on estuarine food webs, as grass shrimp are conduits of detrital energy and a food source for many recreationally and commercially important species in estuaries on the East Coast of the United States and in the Gulf of Mexico. PMID:25353615

  14. Feminization of the Isopod Cylisticus convexus after Transinfection of the wVulC Wolbachia Strain of Armadillidium vulgare

    PubMed Central

    Badawi, Myriam; Grève, Pierre; Cordaux, Richard

    2015-01-01

    Reproductive parasites such as Wolbachia are able to manipulate the reproduction of their hosts by inducing parthenogenesis, male-killing, cytoplasmic incompatibility or feminization of genetic males. Despite extensive studies, no underlying molecular mechanism has been described to date. The goal of this study was to establish a system with a single Wolbachia strain that feminizes two different isopod species to enable comparative analyses aimed at elucidating the genetic basis of feminization. It was previously suggested that Wolbachia wVulC, which naturally induces feminization in Armadillidium vulgare, induces the development of female secondary sexual characters in transinfected Cylisticus convexus adult males. However, this does not demonstrate that wVulC induces feminization in C. convexus since feminization is the conversion of genetic males into functional females that occurs during development. Nevertheless, it suggests that C. convexus may represent a feminization model suitable for further development. Knowledge about C. convexus sexual differentiation is also essential for comparative analyses, as feminization is thought to take place just before or during sexual differentiation. Consequently, we first described gonad morphological differentiation of C. convexus and compared it with that of A. vulgare. Then, wVulC was injected into male and female C. convexus adult individuals. The feminizing effect was demonstrated by the combined appearance of female secondary sexual characters in transinfected adult males, as well as the presence of intersexes and female biases in progenies in which wVulC was vertically transmitted from transinfected mothers. The establishment of a new model of feminization of a Wolbachia strain in a heterologous host constitutes a useful tool towards the understanding of the molecular mechanism of feminization. PMID:26047139

  15. Precursor structure, distribution and possible functions of pigment-dispersing hormone (PDH) in the terrestrial isopod Armadillidium vulgare (Latreille).

    PubMed

    Fouda, Maged Mohamed Ali; Hiragaki, Susumu; Tufail, Muhammad; Shao, Qi-Miao; Takeda, Makio

    2010-12-01

    Pigment-dispersing hormone (PDH) is an 18 amino acid neuropeptide that induces pigment migration in Decapoda and serves as a circadian neurotransmitter in the locomotor activity rhythm in Drosophila. In this study, a cDNA encoding PDH was cloned from adult brains of the pill bug, Armadillidium vulgare (Av). The cDNA comprising 529 bp encodes a peptide (AvPDH) that consists of a putative 26 amino acid signal peptide, and a 34 amino acid PDH-precursor-related peptide containing an 18 amino acid mature peptide. The peptide shows a high sequence identity (55-77%) to crustacean β-PDHs and insect PDFs. The tissue-specific expression pattern was examined by reverse transcription PCR. The transcript is expressed in the brain strongly and ventral nerve cord weakly, but the signal was not detected in the intestinal tract. A similar expression profile appeared in Western blot analyses. Western blot analyses with timed samples showed more intense expression of PDH-like antigen at night. PDH-like immunohistochemical reactivity (PDH-ir) was detected in the optic lobe, anteromedian protocerebrum, accessory lobe, tritocerebrum, and suboesophageal ganglion but the reactivity was faint or nil in the pseudofrontal organ (sinus gland). These results were substantiated by in situ hybridization. Co-localization using anti-Gryllus bimaculatus (Gb)-PDF, anti-Bombyx mori (Bm)-CLK, and anti-Bm-CYC showed a co-localization of these antigens in the optic lobe and SOG. The results provide the first structural and immunocytochemical identification of PDH neurons in terrestrial isopods, and the co-localization of PDH with CLK and CYC supports its possible involvement in circadian clock. A day/night rhythm of PDH content is also a new feature. PMID:20637211

  16. Feminization of the Isopod Cylisticus convexus after Transinfection of the wVulC Wolbachia Strain of Armadillidium vulgare.

    PubMed

    Badawi, Myriam; Grève, Pierre; Cordaux, Richard

    2015-01-01

    Reproductive parasites such as Wolbachia are able to manipulate the reproduction of their hosts by inducing parthenogenesis, male-killing, cytoplasmic incompatibility or feminization of genetic males. Despite extensive studies, no underlying molecular mechanism has been described to date. The goal of this study was to establish a system with a single Wolbachia strain that feminizes two different isopod species to enable comparative analyses aimed at elucidating the genetic basis of feminization. It was previously suggested that Wolbachia wVulC, which naturally induces feminization in Armadillidium vulgare, induces the development of female secondary sexual characters in transinfected Cylisticus convexus adult males. However, this does not demonstrate that wVulC induces feminization in C. convexus since feminization is the conversion of genetic males into functional females that occurs during development. Nevertheless, it suggests that C. convexus may represent a feminization model suitable for further development. Knowledge about C. convexus sexual differentiation is also essential for comparative analyses, as feminization is thought to take place just before or during sexual differentiation. Consequently, we first described gonad morphological differentiation of C. convexus and compared it with that of A. vulgare. Then, wVulC was injected into male and female C. convexus adult individuals. The feminizing effect was demonstrated by the combined appearance of female secondary sexual characters in transinfected adult males, as well as the presence of intersexes and female biases in progenies in which wVulC was vertically transmitted from transinfected mothers. The establishment of a new model of feminization of a Wolbachia strain in a heterologous host constitutes a useful tool towards the understanding of the molecular mechanism of feminization. PMID:26047139

  17. Geographic relatedness and predictability of Escherichia coli along a peninsular beach complex of Lake Michigan

    USGS Publications Warehouse

    Nevers, M.B.; Shively, D.A.; Kleinheinz, G.T.; McDermott, C.M.; Schuster, W.; Chomeau, V.; Whitman, R.L.

    2009-01-01

    To determine more accurately the real-time concentration of fecal indicator bacteria (FIB) in beach water, predictive modeling has been applied in several locations around the Great Lakes to individual or small groups of similar beaches. Using 24 beaches in Door County, Wisconsin, we attempted to expand predictive models to multiple beaches of complex geography. We examined the importance of geographic location and independent variables and the consequential limitations for potential beach or beach group models. An analysis of Escherichia coli populations over 4 yr revealed a geographic gradient to the beaches, with mean E. coli concentrations decreasing with increasing distance from the city of Sturgeon Bay. Beaches grouped strongly by water type (lake, bay, Sturgeon Bay) and proximity to one another, followed by presence of a storm or creek outfall or amount of shoreline enclosure. Predictive models developed for beach groups commonly included wave height and cumulative 48-h rainfall but generally explained little E. coli variation (adj. R2 = 0.19-0.36). Generally low concentrations of E. coli at the beaches influenced the effectiveness of model results presumably because of low signal-to-noise ratios and the rarity of elevated concentrations. Our results highlight the importance of the sensitivity of regressors and the need for careful methods evaluation. Despite the attractiveness of predictive models as an alternative beach monitoring approach, it is likely that FIB fluctuations at some beaches defy simple prediction approaches. Regional, multi-beach, and individual beach predictive models should be explored alongside other techniques for improving monitoring reliability at Great Lakes beaches. Copyright ?? 2009 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.

  18. A Comprehensive Study on Coastline Process and Sedimentary Dynamics, Sardinera Beach, Mona Island, P.R.

    NASA Astrophysics Data System (ADS)

    Rodriguez-Delga, A. M.; Ramirez, W. R.

    2008-12-01

    Sardinera beach in Mona Island, Puerto Rico, has a great recreational and ecological value and is an important research place to gather information on shoreline processes in an area far from the main land and with only scarce man made influences. Beach rock exposures present along the shoreline in Sardinera Beach have increased considerably during the last decade. A new management plan is being developed for Mona Island and the Department of Natural Resources (DNRA) of Puerto Rico wants to better understand the beach sand dynamics on this and other Mona Island beaches. This research includes field and laboratory work that characterize coastal sedimentary processes and helps to better understand the shoreline changes as well as seasonal variations in sand movement and composition. This work also establish the logistics and methodology basis for further studies that will expand to other Mona Island beaches. Benchmarks, GPS coordinates, and landmarks were used to establish ten permanent beach profiles along Sardinera Beach. Beach profiles were (and will be) measured monthly. Sardinera Beach sands are composed mostly of carbonate (CaCO3) components, products of the combination of biological, chemical and diagenetic processes, high grade of micritization, and of lithic limestone fragments. Sand composition differences between Sardinera Beach, the Mona Shelf and adjacent beach, reef crest and reef lagoon systems suggest Sardinera sands are not replenished by the modern marine components produced in these environments. The input of "fresh bioclasts" in this beach seems to be limited by natural (beach rock) and mane made (dock) barriers along the shore and by alteration in the current patterns produced by the man made aperture of the reef. Sardinera's micritized and recrystalized sand deposits seem to have been re-transported between the reefal lagoon and the beach. Sand volume analysis indicates a total sand loss of 1,322 m3 between the months of September to April. Aerial images from the years 1977, 1992 and 2003 show 14 to 27 meters of recession along the coast line.

  19. Bioavailability of cobalt and iron from citric-acid-adsorbed CoFe2O4 nanoparticles in the terrestrial isopod Porcellio scaber.

    PubMed

    Romih, Tea; Drašler, Barbara; Jemec, Anita; Drobne, Damjana; Novak, Sara; Golobi?, Miha; Makovec, Darko; Susi?, Robert; Kogej, Ksenija

    2015-03-01

    The aim of this study was to determine whether citric acid adsorbed onto cobalt ferrite (CoFe2O4) nanoparticles (NPs) influences the bioavailability of their constituents Co and Fe. Dissolution of Co and Fe was assessed by two measures: (i) in aqueous suspension using chemical analysis, prior to application onto the food of test organisms; and (ii) in vivo, measuring the bioavailability in the model terrestrial invertebrate (Porcellio scaber, Isopoda, Crustacea). The isopods were exposed to citric-acid-adsorbed CoFe2O4 NPs for 2 weeks, and tissue accumulation of Co and Fe was assessed. This was compared to pristine CoFe2O4 NPs, and CoCl2 and Fe(III) salts as positive controls. The combined data shows that citric acid enhances free metal ion concentration from CoFe2O4 NPs in aqueous suspension, although in vivo, very similar amounts of assimilated Co were found in isopods exposed to both types of NPs. Therefore, evaluation of the dissolution in suspension by chemical means is not a good predictor of metal assimilation of this model organism; body assimilation of Co and Fe is rather governed by the physiological capacity of P. scaber for the uptake of these metals. Moreover, we propose that citric acid, due to its chelating properties, may hinder the uptake of Co that dissolves from citric-acid-adsorbed CoFe2O4 NPs, if citric acid is present in sufficient quantity. PMID:25437955

  20. Mancae of the parasitic cymothoid isopod, Anilocra apogonae: early life history, host-specificity, and effect on growth and survival of preferred young cardinal fishes

    NASA Astrophysics Data System (ADS)

    Fogelman, R. M.; Grutter, A. S.

    2008-09-01

    Juvenile parasitic cymothoid isopods (mancae) can injure or kill fishes, yet few studies have investigated their biology. While the definitive host of the adult cymothoids is usually a single host from a particular fish species, mancae may use so-called optional intermediate hosts before settling on the definitive host. Little, however, is known about these early interactions. The cymothoid isopod, Anilocra apogonae, infests the definitive host, Cheilodipterus quinquelineatus. This study examined their host preference among potential optional intermediate hosts. Their effect on the growth and mortality of the young of three apogonid fishes, including the definitive host, was investigated. The number of mancae produced per brood was positively correlated with female length. When given a choice of intermediate hosts, significantly more mancae attached to Apogon trimaculatus (Apogonidae) than to Apogon nigrofasciatus. When presented with Ap. trimaculatus and Pomacentrus amboinensis (Pomacentridae), mancae only attached to Ap. trimaculatus suggesting that mancae may show a taxonomic affiliation with preferred hosts. Mancae fed on all three apogonid species, with C. quinquelineatus being fed on earlier than Ap. trimaculatus and Ap. nigrofasciatus. Mancae feeding frequency, adjusted for fish survival, was lowest on C. quinquelineatus and highest on Ap. trimaculatus. Infested apogonids had reduced growth and increased mortality compared with uninfested fish. A. apogonae mancae can use several species of young apogonid fishes as optional intermediate hosts. Via reduced growth and increased mortality, mancae have the potential to negatively influence definitive host populations and also other young species of apogonid fishes.

  1. Conquered from the Deep Sea? A New Deep-Sea Isopod Species from the Antarctic Shelf Shows Pattern of Recent Colonization

    PubMed Central

    Riehl, Torben; Kaiser, Stefanie

    2012-01-01

    The Amundsen Sea, Antarctica, is amongst the most rapidly changing environments of the world. Its benthic inhabitants are barely known and the BIOPEARL 2 project was one of the first to biologically explore this region. Collected during this expedition, Macrostylis roaldi sp. nov. is described as the first isopod discovered on the Amundsen-Sea shelf. Amongst many characteristic features, the most obvious characters unique for M. roaldi are the rather short pleotelson and short operculum as well as the trapezoid shape of the pleotelson in adult males. We used DNA barcodes (COI) and additional mitochondrial markers (12S, 16S) to reciprocally illuminate morphological results and nucleotide variability. In contrast to many other deep-sea isopods, this species is common and shows a wide distribution. Its range spreads from Pine Island Bay at inner shelf right to the shelf break and across 1,000 m bathymetrically. Its gene pool is homogenized across space and depth. This is indicative for a genetic bottleneck or a recent colonization history. Our results suggest further that migratory or dispersal capabilities of some species of brooding macrobenthos have been underestimated. This might be relevant for the species’ potential to cope with effects of climate change. To determine where this species could have survived the last glacial period, alternative refuge possibilities are discussed. PMID:23145160

  2. Conquered from the deep sea? A new deep-sea isopod species from the Antarctic shelf shows pattern of recent colonization.

    PubMed

    Riehl, Torben; Kaiser, Stefanie

    2012-01-01

    The Amundsen Sea, Antarctica, is amongst the most rapidly changing environments of the world. Its benthic inhabitants are barely known and the BIOPEARL 2 project was one of the first to biologically explore this region. Collected during this expedition, Macrostylis roaldi sp. nov. is described as the first isopod discovered on the Amundsen-Sea shelf. Amongst many characteristic features, the most obvious characters unique for M. roaldi are the rather short pleotelson and short operculum as well as the trapezoid shape of the pleotelson in adult males. We used DNA barcodes (COI) and additional mitochondrial markers (12S, 16S) to reciprocally illuminate morphological results and nucleotide variability. In contrast to many other deep-sea isopods, this species is common and shows a wide distribution. Its range spreads from Pine Island Bay at inner shelf right to the shelf break and across 1,000 m bathymetrically. Its gene pool is homogenized across space and depth. This is indicative for a genetic bottleneck or a recent colonization history. Our results suggest further that migratory or dispersal capabilities of some species of brooding macrobenthos have been underestimated. This might be relevant for the species' potential to cope with effects of climate change. To determine where this species could have survived the last glacial period, alternative refuge possibilities are discussed. PMID:23145160

  3. The Chemistry of Sand: Not All Beaches Are Created Equal

    NASA Astrophysics Data System (ADS)

    Newton, A. J.; Brooker, D.; Lyons, J.

    2006-12-01

    In South Carolina, the beaches can be a natural laboratory for scientific inquiry. By middle school most students have visited one of the state's beaches through field trips or family vacations. These fun experiences can be a platform for scientific inquiry and investigation. Many students can describe a beach where the sand was perfect for building sand castles, too sharp to walk on, or just right on a hot summer day. With a dissecting microscope and some weak acid, these observations can be turned into an engaging activity for students to explore the chemical and/or mineralogical make-up of the sand. This presentation will describe an experiment where students use a microscope to draw sand samples and identify some common grains. The students form hypotheses about the amount of carbonate in the samples and test these hypotheses using the weak acid. By the end of the lab students should be able to identify several indications that a chemical reaction has occurred and be able to form and test a hypothesis. They should also understand that sand from different beaches may have different mineralogical compositions. This activity incorporates the following National Science Content Standards: Abilities necessary to do scientific inquiry; understandings about scientific inquiry; properties and changes of properties in matter; chemical reactions; and populations, resources, and environments. The activity was developed with the support of the National Science Foundation's Graduate Teaching Fellows in K-12 Education Program, Award # 0440568.

  4. Plastics Distribution and Degradation on Lake Huron Beaches

    NASA Astrophysics Data System (ADS)

    Zbyszewski, M.; Corcoran, P.

    2009-05-01

    The resistivity of plastic debris to chemical and mechanical weathering processes poses a serious threat to the environment. Numerous marine beaches are littered with plastic fragments that entangle and become ingested by organisms including birds, turtles and plankton. Although many studies have been conducted to determine the amount and effects of plastics pollution on marine organisms, relatively little is known about the distribution and quantity of polymer types along lacustrine beaches. Plastic particles sampled from selected beaches on Lake Huron were analyzed using Fourier Transform Infrared Spectroscopy (FTIR) to determine polymer composition. The majority of the plastic fragments are industrial pellets composed of polypropylene and polyethylene. Varying degrees of oxidation are indicated by multiple irregular peaks in the lower wavenumber region on the FTIR spectra. The oxidized pellets also represent the plastic particles with the most pronounced surface textures, as identified using Scanning Electron Microscopy (SEM). Crazes and flakey, fibrous, or granular textures are consistent with chemical weathering processes, whereas gauges and pits occur through abrasion during mechanical weathering. Further textural and compositional analysis will indicate which polymer types are more resistant to weathering processes. Additional investigation of the distribution of plastic debris along the beaches of Lake Huron will indicate the amount and primary transport directions of resistant plastic debris polluting one of Ontario's Great Lakes.

  5. Empirical Modeling of Microbial Indicators at a South Carolina Beach

    EPA Science Inventory

    Public concerns about water quality at beaches have prompted the development of multiple linear regression and other models that can be used to "nowcast" levels of bacterial indicators. Hydrometeorological and biogeochemical data from summer, 2009 were used to develop empirical m...

  6. Preliminary Model Results of Beach Profile Dynamics with Stratigraphy

    NASA Astrophysics Data System (ADS)

    Reniers, A. J.; Koktas, M.; Gallagher, E. L.; Wadman, H. M.; Brodie, K. L.; Johnson, B. D.; McNinch, J.

    2014-12-01

    The presence of spatial variation in grain size within the surf and swash zone is often ignored in numerical modeling whereas Upon closer inspection, a broad range of grain sizes is visible on a beach. This could potentially lead to a significant mismatch between predictions and observations of profile evolution given the strong sensitivity of sediment transport formulae to the grain size. To explore this in more detail, numerical simulations with XBeach have been performed to simulate the observations of changes in beach profile and stratigraphy within the swash zone at Duck, NC, under a range of wave and tidal conditions (see presentations by Wadman et al., and Gallagher et al. for complementary information on the observations at this conference). The research focus is to establish the morphodynamic response to the sediment dynamics at short and longer time scales in the presence of stratigraphy. A better understanding of the mechanisms and subsequently improved modeling will provide more accurate predictions of the morphodynamic response of the beach during moderate and extreme conditions. It will also help in the interpretation of sediment layering of the beach to relate to past extreme storms on geological time scales.

  7. USGS Sampling Site at Henderson Beach State Park

    USGS Multimedia Gallery

    U.S. Geological Survey (USGS) scientists collected environmental data and samples in coastal areas affected by the 2010 Deepwater Horizon oil spill in the Gulf of Mexico.  Samples of water, sediments, benthic invertebrates, and microorganisms were collected by the USGS at beach, barrier island,...

  8. USGS Collects Sediment Samples at Grand Isle Beach

    USGS Multimedia Gallery

    U.S. Geological Survey (USGS) scientists collected environmental data and samples at beach, barrier island, and wetland sites in response to the 2010 Deepwater Horizon oil spill in the Gulf of Mexico.  The USGS Florida, Alabama, Mississippi, Louisiana, and Texas Science Centers collaborated to ...

  9. USGS Sediment Sampling at Henderson Beach State Park

    USGS Multimedia Gallery

    U.S. Geological Survey (USGS) scientists collected environmental data and samples in coastal areas affected by the 2010 Deepwater Horizon oil spill in the Gulf of Mexico.  Samples of water, sediments, benthic invertebrates, and microorganisms were collected by the USGS at beach, barrier island,...

  10. Wireless Time Tracking Improves Productivity at CSU Long Beach.

    ERIC Educational Resources Information Center

    Charmack, Scott; Walsh, Randy

    2002-01-01

    Describes California State University Long Beach's implementation of new maintenance management software, which integrated maintenance, inventory control, and key control and allows technicians to enter and receive information through handheld wireless devices for more accurate time accounting. The school estimates a 10 percent increase in…

  11. Seafloor off Natural Bridges State Beach, Santa Cruz, California

    USGS Publications Warehouse

    Storlazzi, Curt D.; Golden, Nadine E.; Gibbons, Helen

    2013-01-01

    The seafloor off Natural Bridges State Beach, Santa Cruz, California, is extremely varied, with sandy flats, boulder fields, faults, and complex bedrock ridges. These ridges support rich marine ecosystems; some of them form the "reefs" that produce world-class surf breaks. Colors indicate seafloor depth, from red-orange (about 2 meters or 7 feet) to magenta (25 meters or 82 feet).

  12. 20. 8" PIPELINE ON BEACH AND ALONG PALI, VIEW WEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. 8" PIPELINE ON BEACH AND ALONG PALI, VIEW WEST TOWARD KALAWAO. NOTE GATE VALVE (LARGER) AND BLOW-OFF VALVE (SMALLER). PIPELINE GENERALLY AT 20' ABOVE SEA LEVEL. - Kalaupapa Water Supply System, Waikolu Valley to Kalaupapa Settlement, Island of Molokai, Kalaupapa, Kalawao County, HI

  13. 75 FR 82382 - Beaches Environmental Assessment and Coastal Health Act

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-30

    ... formula introduced with the fiscal year 2010 grants (see 75 FR 1373, January 11, 2010). How does EPA... announcing the availability of the fiscal year 2010 grants (75 FR 1373, January 11, 2010). How will the... FR 15446, 15449 (March 31, 2003)). For the 2011 beach season, the deadline for states to...

  14. International Integration of California State University, Long Beach.

    ERIC Educational Resources Information Center

    Harari, Maurice

    The Center for International Education was designed to stimulate, plan, organize, develop, and administer a series of programs and services to deepen the international dimensions of the instructional, research, and public service functions of the California State University at Long Beach. It works with varied university constituencies, the…

  15. Experiences of returning to elite beach volleyball after shoulder injury

    PubMed Central

    Bele, Sofie; Östenberg, Anna Hafsteinsson; Sjöström, Rita; Alricsson, Marie

    2015-01-01

    The purpose of this study was to examine beach volleyball players’ experience regarding shoulder injury and how it affects their return to play. To achieve the research aims a qualitative design with semi-structured interviews had been conducted, five elite beach volleyball players, four men and one woman aged 27–42 participated in the study. All participants had suffered a severe shoulder injury, with absence from training and competing for at least 28 days. The findings of this study indicate that it is the individual’s inner motivation, together with a clear goal and support from the community, family, teammate and coach that are the most important factors when going through rehabilitation and getting back to playing beach volleyball after a shoulder injury. All participants had been affected by their injury in some way; some of the participants had been affected in a positive way since they had become mentally stronger and had developed better volleyball technique after rehabilitation. The conclusions of this study indicate that there are three distinct factors that increase the chances of getting back to playing beach volleyball after shoulder injury; it is the players’ self motivation, together with a clear goal and support from the community. PMID:26331135

  16. Golden opportunities: A horizon scan to expand sandy beach ecology

    NASA Astrophysics Data System (ADS)

    Schlacher, Thomas A.; Weston, Michael A.; Schoeman, David S.; Olds, Andrew D.; Huijbers, Chantal M.; Connolly, Rod M.

    2015-05-01

    Robust ecological paradigms and theories should, ideally, hold across several ecosystems. Yet, limited testing of generalities has occurred in some habitats despite these habitats offering unique features to make them good model systems for experiments. We contend this is the case for the ocean-exposed sandy beaches. Beaches have several distinctive traits, including extreme malleability of habitats, strong environmental control of biota, intense cross-boundary exchanges, and food webs highly reliant on imported subsidies. Here we sketch broad topical themes and theoretical concepts of general ecology that are particularly well-suited for ecological studies on sandy shores. These span a broad range: the historical legacies and species traits that determine community assemblages; food-web architectures; novel ecosystems; landscape and spatial ecology and animal movements; invasive species dynamics; ecology of disturbances; ecological thresholds and ecosystem resilience; and habitat restoration and recovery. Collectively, these concepts have the potential to shape the outlook for beach ecology and they should also encourage marine ecologists to embrace, via cross-disciplinary ecological research, exposed sandy beach systems that link the oceans with the land.

  17. Experiences of returning to elite beach volleyball after shoulder injury.

    PubMed

    Bele, Sofie; Östenberg, Anna Hafsteinsson; Sjöström, Rita; Alricsson, Marie

    2015-08-01

    The purpose of this study was to examine beach volleyball players' experience regarding shoulder injury and how it affects their return to play. To achieve the research aims a qualitative design with semi-structured interviews had been conducted, five elite beach volleyball players, four men and one woman aged 27-42 participated in the study. All participants had suffered a severe shoulder injury, with absence from training and competing for at least 28 days. The findings of this study indicate that it is the individual's inner motivation, together with a clear goal and support from the community, family, teammate and coach that are the most important factors when going through rehabilitation and getting back to playing beach volleyball after a shoulder injury. All participants had been affected by their injury in some way; some of the participants had been affected in a positive way since they had become mentally stronger and had developed better volleyball technique after rehabilitation. The conclusions of this study indicate that there are three distinct factors that increase the chances of getting back to playing beach volleyball after shoulder injury; it is the players' self motivation, together with a clear goal and support from the community. PMID:26331135

  18. 25. Photocopy of photograph (from Division of Beaches and Parks, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    25. Photocopy of photograph (from Division of Beaches and Parks, State of California, Department of Natural REsources) Photographer unknown, Date unknown SUTTER'S MAP OF FORT WITH SUPERIMPOSED OUTLINE OF FORT - Sutter's Fort, L & Twenty-Seventh Streets, Sacramento, Sacramento County, CA

  19. Health effects of beach water pollution in Hong Kong.

    PubMed Central

    Cheung, W. H.; Chang, K. C.; Hung, R. P.; Kleevens, J. W.

    1990-01-01

    Prospective epidemiological studies of beach water pollution were conducted in Hong Kong in the summers of 1986 and 1987. For the main study in 1987, a total of 18741 usable responses were obtained from beachgoers on nine beaches at weekends. The study indicated the overall perceived symptom rates for gastrointestinal, ear, eye, skin, respiratory, fever and total illness were significantly higher for swimmers than non-swimmers; and the swimming-associated symptom rates for gastrointestinal, skin, respiratory and total illness were higher at 'barely acceptable' beaches than at 'relatively unpolluted' ones. Escherichia coli was found to be the best indicator of the health effects associated with swimming in the beaches of Hong Kong. It showed the highest correlation with combined swimming-associated gastroenteritis and skin symptom rates when compared with other microbial indicators. A linear relationship between E. coli and the combined symptom rates was established. Staphylococci were correlated with ear, respiratory and total illness, but could not be used for predicting swimming-associated health risks. They should be used to complement E. coli. The setting of health-related bathing-water quality standards based on such a study is discussed. PMID:2384140

  20. Proposal: A Microfilm System for Long Beach City College.

    ERIC Educational Resources Information Center

    Maas, Michael L.

    In order to effectively manage the increasing quantity of student records of the Long Beach Community College District, a systematic microfilming of many of the student records must begin in the immediate future. This section of the Admissions and Records Staff's 1975 review of the records system recommends that a 16mm Cartridge System (from a…

  1. 2. COTTAGES, NORTH SIDE OF OCEAN PATHWAY EAST OF BEACH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. COTTAGES, NORTH SIDE OF OCEAN PATHWAY EAST OF BEACH AVENUE, (NOS. 17, 15, 13, 11, 7 AND 5), GENERAL VIEW LOOKING NORTH - Town of Ocean Grove, East terminus of State Route 33, south of Asbury Park, Ocean Grove, Monmouth County, NJ

  2. A new modelling concept for aeolian sediment transport on beaches

    NASA Astrophysics Data System (ADS)

    de Vries, S.; Arens, S. M.; Stive, M. J. F.; Ranasinghe, R.

    2012-04-01

    This paper presents a new modelling concept for aeolian transport on beaches. Many research is invested in describing aeolian sediment transport for desert situations. Some of the principles of aeolian sediment transport in deserts are valid for application at the coastal zone but, where in deserts abundant sand is available for transport, in coastal situations sediment availability is limited. Sediment availability (or supply) is limited due to supply limiting factors such as moisture content of the bed, fetch effects and armouring of the surface. We propose a new sediment transport concept where we quantify aeolian sediment transport while quantifying the sediment availability rather than the more conventional (Bagnold, 1954) wind driven transport capacity. The concept is illustrated using field data. The field data is collected during a measurement campaign which has been designed to measure aeolian transport with special focus on sediment availability. Wind and sediment transport rates are measured on a beach for a period of 1 week. During this week onshore wind occurred allowing the analysis of aeolian transport across the beach towards the dunes. A total of 5 sediment transport gauges are dynamically placed over the cross section of the beach from locations in the intertidal zone (at low tide) until the dunefoot. The observations show that the amount of aeolian transport is very much dependent on the tidal phase. Low tides correspond to large aeolian transport and high tides to significantly lower aeolian transport across the beach. Wind conditions during the experiment were relatively constant implying that the specific variability in time of the measured aeolian transport is caused by variability with respect to the source rather than variability in wind conditions. Additional to this specific case, existing data of similar experiments (Arens, 1996) are analysed. Re-analysing this data, from experiments covering larger timespans, more evidence is found for source (or availability) related variability in measured aeolian transport rates. The measurements support the concept of allowing a dominant role for sediment availability over wind driven transport capacity in sediment transport formulations. Moreover, these measurements allow for an initial formulation of a new sediment transport relation suitable for quantifying aeolian sediment transport on beaches. The new sediment transport formulation is fundamentally different from existing Bagnold type formulations but, shows large generic potential to quantify and predict aeolian sediment transport on beaches and other situations with limited sand supply.

  3. Seasonal Variation of Surface Sediments in the Gochang Beach, Korea

    NASA Astrophysics Data System (ADS)

    Ryang, Woo Hun; Kang, Sol Ip

    2014-05-01

    The Gochang Beach, located on the southwestern coast of Korea, was studied in terms of four season variations of surface sediment and sedimentary environment. The Gochang Beach consists of the Dongho, Kwangseungri, Myeongsasipri beaches from north to south. During the four seasons of spring (May), summer (August), and fall (November), and winter (February), surface sediments of 135 sites were sampled across nine survey lines (15 sites in each survey line), respectively. The pocket-type Dongho Beach is mainly composed of fine to coarse sands, and the ratio of fine sand is the largest. The average of grain size is the coarsest in the summer. The spatial distribution of surface sediments shows a coast-parallel band of fine and medium sands during three seasons of spring, fall, and winter, whereas medium sands dominated in the northern part of the study area during the summer. These results suggest that a tide is more effective than a wave in the surface sediments of the Dongho Beach during the summer. The surface sediments of the Kwangseungri Beach are mainly composed of fine-grained sands, and the mean grain size is the coarsest in winter. Mud facies partly exists in summer, whereas it is nearly absent in winter. The spatial distribution of surface sediments shows a coast-parallel band of fine and medium sands during spring, fall, and winter. In the northern part, the study area is dominated by fine sands during summer, whereas by coarse sands during winter. These results are interpreted that tide is more effective than wave on the surface sediment distribution of the Kwangseungri Beach during summer season. The open-coast Myeongsasipri Beach is mainly composed of fine to medium sand, the distribution of which shows a coast-parallel trend. Grain-size distribution shows a bi-modal trend in the summer and winter and a uni-mode in the spring and fall. Grain size of the winter is the coarsest among those of four seasons. During the winter, the upper tidal flat was dominated by medium sand, while the lower tidal flat was dominated by find sand. Such a feature is attributed to wave-dominated sedimentation in the winter. The dominant finer-grain size of the summer rather than that of the winter is interpreted that tidal energy played an important role in the tidal flat sedimentation during the summer. Sedimentary environments of the Myeongsasipri Beach are suggestive of a seasonal change from wave-dominated conditions in the winter to tide-dominated conditions in the summer as a result of seasonal variations of the intensity of onshore-directed winds and waves. Keywords: seasonal variation, surface sediment, macro-tide, beach, Gochang Acknowledgements: This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2010-0025733) and by the Korea Institute of Marine Science and Technology Promotion (KIMST) through the project grant of Tracking and Prediction on Impacts of Ancient Extreme Climatic Events in the West and South Coastal Zone of Korea.

  4. Carbonate Beaches: A Balance Between Biological and Physical Processes

    NASA Astrophysics Data System (ADS)

    Nairn, R.; Risk, M.

    2004-12-01

    Carbonate beaches are a unique example of the interaction between biological processes, creating the sediments, and physical processes, moving and often removing the sediments. On the sediment supply side, carbonate sediments are born, not made. They exist in dynamic equilibrium between production and destruction. Following the creation of carbonate sediment in coral reef and lagoon environments, the sediments are moved shoreward to the beach, transport along the shore and sometimes, eventually lost offshore, often as the result of tropical storms. Comprehensive studies of the balance between the supply and loss of carbonate sediments and beach dynamics have been completed for the islands of Mauritius and Barbados. Field studies and remote sensing (Compact Airborne Spectrometry Imaging) have been applied to develop carbonate sediment production rates for a range of reef and lagoon conditions. Using GIS, these production rates have been integrated to determine sediment supply rates for different segments of the coastline. 1-D and 2-D models of waves, hydrodynamics, sediment transport and morphodynamics were set-up and tested against observed beach response to storm events or a sequence of storm events. These complex deterministic models are not suitable for application over periods of decades. However, it was possible to characterize storm events by the extent of sand loss, and relate this to key descriptive factors for groups of storm events, thereby encapsulating the erosion response. A long-term predictive tool for evaluating beach erosion and accretion response, over a period of several decades, was developed by combining the supply rates for carbonate sediment and the encapsulated representation of the loss rates through physical processes. The ability of this predictive tool was successfully tested against observed long term beach evolution along sections of the coast in Barbados and Mauritius using air photo analysis in GIS for shoreline change over periods of 40 years. The long-term predictive tool for carbonate beach evolution provided valuable support to developing coastal zone management policy and actions to preserve the beaches in their natural form, minimizing the need for artificial nourishment of the beaches. Many models of sediment movement on shorelines are derived from clastic examples, and fit carbonate coastlines only with difficulty. We have combined field surveys of benthic biota, estimates of sediment production from skeletal growth and bioerosion, and sediment destruction by comminution and dissolution with dynamic models of sediment movement in the littoral zone, achieving improved understanding of coastal processes of erosion and deposition. Mauritius is fringed by shallow lagoons, often with luxuriant stands of Acropora. The offshore region is exhumed Pleistocene-all the sediment on the beaches comes from the lagoons. From surveys of coral cover, and estimates of sediment production from reef, sand and hardground areas, we produced dynamic models that faithfully hindcast shoreline dynamics for decades, and allowed identification of regions especially vulnerable to erosion. On the south coast of Barbados, one of the main issues in stabilising and rehabilitation the coastline is the balance between sediment from longshore drift and local sources. By identifying localised areas of characteristic sediment-producers (e.g., the foraminiferan Homotrema rubrum, the green alga Halimeda), we were able to determine the balance between proximal and distal sediment sources. The resulting model hindcasts the coastline through all the major hurricanes of the past 30 years.

  5. Morphological developments after a beach and shoreface nourishment at Vlugtenburg beach, the Netherlands

    NASA Astrophysics Data System (ADS)

    de Schipper, M. A.; de Vries, S.; Ranasinghe, R.; Reniers, A. J. H. M.; Stive, M. J. F.

    2012-04-01

    For the last decades Dutch coastal policy requires sand nourishments to mitigate the effects of coastal erosion. Over time, the nourishment strategy has evolved from direct protection approach to a feeder approach; instead of placing the sand on the beach or dune where it directly benefits safety, sand is placed on the shoreface or alongshore concentrated. Subsequently natural processes redistribute the sand over the profile and alongshore. With the shift in nourishment approach, a study was started to investigate in detail how nourished sand is redistributed in space and time. Here we present results from a high resolution bathymetric survey campaign conducted at Vlugtenburg beach at the south west coast of the Netherlands. At this site a beach and shoreface nourishment of 5.4 million m3 was installed in spring 2009, moving the shoreline approximately 250 m forward. Since the completion of the project, a total of 22 profiles were measured monthly extending from the dunefoot to 9 m below mean sea level. These surveys are executed using walking GPS surveys for the subaerial part and jetski surveys for the subaqueous part. Observations show that the morphodynamic evolution can be characterized by two stages; first a period of rapid changes followed by a period of more stable topography. In the first period, 12 to 15 months after construction, a large cross shore (offshore) movement of the nourished sand is found. The cross shore movement results from a rapid adaptation of the construction profile (characterized by a steep foreshore slope from -2 to -4 m) to a more natural profile with a large subtidal bar. A sediment budget analysis over all 28 surveys up to present shows a gradual loss of volume. As topographic changes below the -8 m and above +3 m are small, it is most likely that the majority of the sediment deficit can be contributed to alongshore losses. Furthermore, the domain itself is subdivided in various coastal sections, revealing that the cross shore volumetric changes within the domain are significantly larger than the alongshore losses. As a consequence of the adaptation process the high waterline has retreated approximately 50 m over the last 2 years. The observed changes are correlated with nearby wave data to investigate the impact of storm events. It is observed that in autumn when wave forcing is strong, the profile adaptation is accelerated. The impact of storm events is visible most clearly in the active marine zone (+1 to -4m). Higher up the profile the volume changes are much more gradual. The findings of this study show the impact of the cross shore location of a nourishment in the profile. If the man-made profile consists of steep unnatural slopes in the active marine zone, a fast cross shore adaptation can be expected.

  6. Quantification of toxic metals derived from macroplastic litter on Ookushi Beach, Japan.

    PubMed

    Nakashima, Etsuko; Isobe, Atsuhiko; Kako, Shin'ichiro; Itai, Takaaki; Takahashi, Shin

    2012-09-18

    The potential risk of toxic metals that could leach into a beach environment from plastic litter washed ashore on Ookushi Beach, Goto Islands, Japan was estimated by balloon aerial photography, in situ beach surveys, and leaching experiments in conjunction with a Fickian diffusion model analysis. Chromium (Cr), cadmium (Cd), tin (Sn), antimony (Sb), and lead (Pb) were detected in plastic litter collected during the beach surveys. Polyvinyl chloride (PVC) fishing floats contained the highest quantity of Pb. Balloon aerial photography in conjunction with a beach survey gave an estimated mass of Pb derived from plastic litter of 313 ± 247 g. Lead leaching experiments on collected PVC floats showed that Pb in the plastic litter could leach into surrounding water on the actual beach, and that plastic litter may act as a "transport vector" of toxic metals to the beach environment. Using the experimental data, the total mass of Pb that could leach from PVC plastic litter over a year onto Ookushi Beach was estimated as 0.6 ± 0.6 g/year, suggesting that toxic metals derived from plastic beach litter are a potential "pathway" to contamination of the beach environment due to their accumulation in beach soil over time. PMID:22916725

  7. Low-energy Beach ridge sedimentation in the Mississippi River delta plain

    SciTech Connect

    Gerdes, R.G.; Penland, S.

    1985-01-01

    Regressive beach ridge plains, such as Cheniere Caminada, Cheniere Caillou, and Cheniere Ronquille, are common depositional features within the Mississippi River delta plain in southeastern Louisiana. Vibracored sequences indicate beach ridge formation is a 3 stage process: Stage 1: Distributary Progradation, followed by Stage 2: Longshore Transport Interception, and completed by Stage 3: Beach Ridge Progradation. Cheniere Caminada is the largest beach ridge plain and is associated with the Late Lafourche delta. Radiocarbon dates indicate beach ridge building began approximately 720 years BP, when the Bayou Lafourche distributaries built seaward of the older, retreating Bayou Blue shoreline and intercepted westward longshore sediment transport, resulting in the progradation of Cheniere Caminada. Near the fan apex, beach ridges are 7-8 m thick and thin westward 2-3 m thick against the levees of Bayou Moreau. A typical beach ridge vertical sequence coarsens upward, with shoreface silty sands overlain by a thin cap of beach, washover, and aeolian sands. Beach ridge progradation in this area ceased approximately 300 years BP with the abandonment of Bayou Lafourche. The documentation of multiple regressive beach ridge plains suggest these deposits are stratigraphically more significant in the Mississippi River delta plain than recognized previously. The regressive beach ridge sequence documented in this study both stratigraphically and genetically contrasts with the classic transgressive chenier ridges of southwestern Louisiana.

  8. Field evidence of beach profile evolution toward equilibrium

    NASA Astrophysics Data System (ADS)

    Ludka, B. C.; Guza, R. T.; O'Reilly, W. C.; Yates, M. L.

    2015-11-01

    An equilibrium framework is used to describe the evolution of the cross-shore profile of five beaches (medium grain size sand) in southern California. Elevations were observed quarterly on cross-shore transects extending from the back beach to 8 m depth, for 3-10 years. Transects spaced 100 m in the alongshore direction are alongshore averaged into nineteen 700-900 m long sections. Consistent with previous observations, changes about the time average profile in many sections are captured by the first mode empirical orthogonal function (EOF). The first EOF poorly describes sections with hard substrate (less than roughly 80% sandy bottom) and also fails near the head of a submarine canyon and adjacent to an inlet. At the 12 well-described sections, the time-varying amplitude of the first EOF, the beach state A, describes the well-known seasonal sand exchange between the shoreline and offshore (roughly between 4 and 7 m depth). We show that the beach state change rate dA/dt depends on the disequilibrium between the present state A and wave conditions, consistent with the equilibrium concepts of Wright and Short (1984) and Wright et al. (1985). Empirically determined, optimal model coefficients using the framework of Yates et al. (2009a, 2011) vary between sections, but a single set of globally optimized values performs almost as well. The model implements equilibrium concepts using ad hoc assumptions and empirical parameter values. The similarity with observed profile change at five southern California beaches supports the underlying model equilibrium hypotheses, but for unknown reasons the model fails at Duck, NC.

  9. Beach Profile Behaviour in Tidal Environments: A Morphological Model

    NASA Astrophysics Data System (ADS)

    Bernabeu, A. M.; Medina, R.; Vidal, C.

    2004-05-01

    Tourism is an important economical activity in Spain that represents 10% of its GDP and provides a million jobs. Spain is the world's second more visited country, receiving 7% of world tourists. Eighty per cent of these visitors choose their destination somewhere along the 2500 km of beaches. Consequently, many efforts are currently addressed to their maintenance and conservation. However, the coastal management policies must be sustained by the deep knowledge of the beach behaviour and the physical processes implied. A morphological model, with certain predictive capacities, to describe the beach profile behaviour is proposed, integrating the wave and tide influence. It is based on the concept of the two-section (surf and shoaling) equilibrium beach profile, and has been validated with field and laboratory data. The model is described by means of two parameters: the modal tidal range and the dimensionless fall velocity (? ). Tide is considered a local variable whose principal effect is the lengthening of the intertidal or surf profile. The greater the tidal range, the wider the intertidal profile. The dimensionless fall velocity defines the transition from dissipative to reflective situations in beaches of any given tidal range. The morphological changes predicted by the proposed model in the surf and shoaling sections occur in the opposite direction. Whilst in the surf profile the slope close to the high tidal level becomes steeper and the concavity of whole section increases; in the shoaling profile, the upper part flattens resulting in a less concave section related to the decrease of ? . In this transition, the slope break between surf and shoaling profiles becomes smoother and difficult to identify. This work was funded by projects REN2003-02822 MAR, REN2003-03233 MAR, VEM2003-20093-C03-03 of the Spanish MCYT and PGDIT03RMA30101PR of the Galician Government (XUGA). Contribution No 304 of XM2 group.

  10. Modeling system for predicting enterococci levels at Holly Beach.

    PubMed

    Zhang, Zaihong; Deng, Zhiqiang; Rusch, Kelly A; Walker, Nan D

    2015-08-01

    This paper presents a new modeling system for nowcasting and forecasting enterococci levels in coastal recreation waters at any time during the day. The modeling system consists of (1) an artificial neural network (ANN) model for predicting the enterococci level at sunrise time, (2) a clear-sky solar radiation and turbidity correction to the ANN model, (3) remote sensing algorithms for turbidity, and (4) nowcasting/forecasting data. The first three components are also unique features of the new modeling system. While the component (1) is useful to beach monitoring programs requiring enterococci levels in early morning, the component (2) in combination with the component (1) makes it possible to predict the bacterial level in beach waters at any time during the day if the data from the components (3) and (4) are available. Therefore, predictions from the component (2) are of primary interest to beachgoers. The modeling system was developed using three years of swimming season data and validated using additional four years of independent data. Testing results showed that (1) the sunrise-time model correctly reproduced 82.63% of the advisories issued in seven years with a false positive rate of 2.65% and a false negative rate of 14.72%, and (2) the new modeling system was capable of predicting the temporal variability in enterococci levels in beach waters, ranging from hourly changes to daily cycles. The results demonstrate the efficacy of the new modeling system in predicting enterococci levels in coastal beach waters. Applications of the modeling system will improve the management of recreational beaches and protection of public health. PMID:26186681

  11. Beach Soccer Injuries During the Japanese National Championships

    PubMed Central

    Shimakawa, Tomoyuki; Shimakawa, Yusuke; Kawasoe, Yoko; Yoshimura, Kouji; Chinen, Yuma; Eimon, Kazuya; Chibana, Wataru; Shirota, Shinichi; Kadekawa, Kei; Bahr, Roald; Uezato, Tomomi; Ikeda, Hiroshi

    2016-01-01

    Background: The frequency and severity of injury in beach soccer are unknown. Purpose: To estimate the incidence rates, characteristics, and risk factors for injuries associated with beach soccer. Study Design: Cohort study; Level of evidence, 3. Methods: The same sports physician examined and recorded injuries incurred during the Japanese National Beach Soccer Championships in 2013 and 2014. Posttournament follow-up was made for all injuries. Match exposure for each player was recorded through video review to examine individual risk factors. Results: A total of 58 injuries were recorded during 54 matches. The overall injury rate was 179.0 (95% CI, 138.4-231.6), and the time-loss injury rate was 28.2 (95% CI, 14.7-54.1) per 1000 player-hours. The foot/toe (34.9%) was the most frequently injured area, followed by the lower leg (22.2%) and thigh (11.1%). There was only 1 ankle injury (1.6%). The most frequent injury type was contusions (60.3%), followed by lacerations/abrasions (14.3%) and sprains/ligament injuries (6.3%). Only 4 injuries resulted in ≥30 days of time-loss (7.4%). After adjusting for age, a previous history of severe injury and longer experience of beach soccer were significantly associated with injury risk. Conclusion: The time-loss injury rate in this study was comparable to the rates reported during the matches of soccer or futsal tournaments. However, a greater incidence of foot/toe injury and lacerations/abrasions as well as a lower incidence of ankle injury distinguished beach soccer from soccer and futsal, possibly related to the specific playing conditions of being barefoot on a sand surface. PMID:26862537

  12. Two-Dimensional Numerical Modeling of Anthropogenic Beach Berm Erosion

    NASA Astrophysics Data System (ADS)

    Shakeri Majd, M.; Schubert, J.; Gallien, T.; Sanders, B. F.

    2014-12-01

    Anthropogenic beach berms (sometimes called artificial berms or artificial dunes) temporarily enhance the ability of beaches to withstand overtopping and thus guard against coastal flooding. However, the combination of a rising tide, storm surge, and/or waves may erode anthropogenic berms in a matter of hours or less and cause flooding [1]. Accurate forecasts of coastal flooding therefore demand the ability to predict where and when berms fail and the volume of water that overtops into defended coastal lowlands. Here, a two-dimensional numerical model of swash zone waves and erosion is examined as a tool for predicting the erosion of anthropogenic beach berms. The 2D model is known as a Debris Flow Model (DFM) because it tightly couples flow and sediment transport within an approximate Riemann solver and is able to resolve shocks in fluid/sediment interface [2]. The DFM also includes a two dimensional avalanching scheme to account for gravity-driven slumping of steep slopes. The performance of the DFM is examined with field-scale anthropogenic berm erosion data collected at Newport Beach, California. Results show that the DFM can be applied in the swash zone to resolve wave-by-wave flow and sediment transport. Results also show that it is possible to calibrate the model for a particular event, and then predict erosion for another event, but predictions are sensitive to model parameters, such as erosion and avalanching. References: [1] Jochen E. Schubert, Timu W. Gallien, Morteza Shakeri Majd, and Brett F. Sanders. Terrestrial laser scanning of anthropogenic beach berm erosion and overtopping. Journal of Coastal Research In-Press, 2014. [2] Morteza Shakeri Majd and Brett F. Sanders. The LHLLC scheme for Two-Layer and Two-Phase transcritical flows over a mobile bed with avalanching, wetting and drying. Advances in Water Resources, 64, 16-31, 2014.

  13. One dimensional modeling of anthropogenic beach berm erosion

    NASA Astrophysics Data System (ADS)

    Shakeri Majd, M.; Sanders, B. F.

    2013-12-01

    Anthropogenic beach berms (sometimes called artificial berms or artificial dunes) are in use internationally to guard against beach overtopping and consequent coastal flooding. Berms can be constructed on a seasonal basis or in anticipation of a hazardous event, e.g., when a storm is expected to arrive coincident with an astronomical high tide. In either case, a common approach is to scrape sand from the foreshore with heavy equipment and deposit it on the crest of the natural beach dune, thus providing added protection from the possibility of wave overtopping. Given the potential for higher sea levels globally and more extreme storm events, anthropogenic berms will surely be tested to their limits and will ultimately fail, causing flooding. A better understanding of the conditions under which these berms fail is therefore needed to support coastal flood risk management. An experimental campaign in Newport Beach, California was conducted to document the dynamic erosion of prototype beach berms under a rising tide and mild to moderate wave conditions. Terrestrial laser scanning (TLS) of the berm produced a digital model of how the berm shape evolved over time. Here, a numerical model of swash zone hydromorphodynamics based on shallow-water flow physics is presented to evaluate whether and to what extent the timing and degree of berm erosion and overtopping can be predicted from first principles. The model tightly couples flow and sediment transport within an approximate Riemann solver, and thus is of the Godunov-type variety of finite volume schemes. Additionally, the model includes an avalanching scheme to account for non-hydrodynamic slumping down the angle of repose. Results indicate that it is possible to calibrate the model for a particular event, and then successfully predict erosion for another event, but due to parameter sensitivities, it is unlikely that the model can be applied at a site without calibration (true prediction).

  14. Competitive interactions in macroinfaunal animals of exposed sandy beaches.

    PubMed

    Dugan, Jenifer E; Jaramillo, Eduardo; Hubbard, David M; Contreras, Heraldo; Duarte, Cristian

    2004-05-01

    The influence of biotic interactions in structuring macroinfaunal communities of exposed sandy beaches, an unstable habitat characterized by strong physical forces, is generally considered negligible. We investigated the hypothesis that competitive interactions during burrowing could potentially affect the intertidal distribution and abundance of macroinfaunal animals of sandy beaches using two species of invertebrates, a hippid crab, Emerita analoga, and a bivalve, Mesodesma donacium, common along the coast of Chile. Spatial overlap in the intertidal distributions of these species was dynamic, varying with abundance, location, time of year and tide. Highest density zones of each species were often distinctly separated at low tide and spatial overlap in their distributions decreased significantly with increasing density, suggesting density dependence of the interactions. Negative relationships between densities of the two species at the smallest spatial scale examined also suggested active interactions among individuals. Over a tidal cycle, peak densities of the two species overlapped suggesting that interactions could occur frequently. Burrowing performance of E. analoga varied between size classes in three experimental densities of clams (5, 10 and 15 clams 0.008 m(-2)) and in controls with no clams. Burrowing times of large crabs were significantly longer (approximately twofold) in all densities of clams than in controls, while those of small crabs did not differ significantly among treatments and controls. Large crabs also displaced clams from the sand while burrowing suggesting that two mechanisms of direct interference can occur, both of which could increase exposure of individuals involved to active swash and transport across or along the beach with potentially negative consequences. Our results suggest that competitive interactions capable of affecting zonation and population and community biology on a number of scales can occur among burrowing macroinfauna on exposed sandy beaches. Those interactions could be more ecologically significant than previously appreciated and may contribute to patterns observed in community structure and zonation on sandy beaches. Our results illustrate the potential importance of negative biological interactions in a physically stressful environment. PMID:15067539

  15. A baseline assessment of beach debris and tar contamination in Bonaire, Southeastern Caribbean.

    PubMed

    Debrot, Adolphe O; van Rijn, Jimmy; Bron, Patrick S; de León, Ramon

    2013-06-15

    Data on beach debris and tar contamination is provided for 21 natural beach sites in Bonaire, Southeastern Caribbean. Transects amounting to a combined length of 991 m were sampled March-May 2011 and a total of 8960 debris items were collected. Highest debris and tar contamination were found on the beaches of the windward east-coast of the island where geometric mean debris concentrations (± approx. 70% confidence limits) were 115±58 items m(-1) and 3408±1704 g m(-1) of beach front. These levels are high compared to data collected almost 20 years earlier on the nearby island of Curaçao. Tar contamination levels averaged 223 g m(-1) on windward beaches. Contamination levels for leeward west-coast beaches were generally two orders of magnitude less than windward beaches. PMID:23497789

  16. Linking social drivers of marine debris with actual marine debris on beaches.

    PubMed

    Slavin, Chris; Grage, Anna; Campbell, Marnie L

    2012-08-01

    The drivers (social) and pressures (physical) of marine debris have typically been examined separately. We redress this by using social and beach surveys at nine Tasmanian beaches, across three coastlines and within three categories of urbanisation, to examine whether people acknowledge that their actions contribute to the issue of marine debris, and whether these social drivers are reflected in the amount of marine debris detected on beaches. A large proportion (75%) of survey participants do not litter at beaches; with age, gender, income and residency influencing littering behaviour. Thus, participants recognise that littering at beaches is a problem. This social trend was reflected in the small amounts of debris that were detected. Furthermore, the amount of debris was not statistically influenced by the degree of beach urbanisation, the coastline sampled, or the proximity to beach access points. By linking social and physical aspects of this issue, management outcomes can be improved. PMID:22704152

  17. Survival trends of Staphylococcus aureus, Pseudomonas aeruginosa, and Clostridium perfringens in a sandy South Florida beach.

    PubMed

    Mohammed, R L; Echeverry, A; Stinson, C M; Green, M; Bonilla, T D; Hartz, A; McCorquodale, D S; Rogerson, A; Esiobu, N

    2012-06-01

    The search for alternative indicators of disease-risk from non-enteric pathogens at the beach revealed high densities of targeted bacteria. To explain the high numbers of potential non-enteric pathogens, Staphylococcus aureus and Pseudomonas aeruginosa, in beach sand, we investigated factors affecting their survival and distribution, as well as those of a potential fecal indicator, Clostridium perfringens. Results indicated greater S. aureus and P. aeruginosa survival and proliferation in sterile beach sand, than seawater, with diminished numbers upon exposure to natural micro-predators. C. perfringens remained relatively consistent with initial numbers. Intermediate sand particles (850 ?m-2 mm) constituted the major micro-niche; creating implications for beach classification programs. Colonization of sterile sand boxes at the beach by S. aureus and P. aeruginosa confirmed the filtering action (>100×) of beach sand. The use of these potential pathogens in periodic sanitary evaluation of beach sand quality is indicated, regardless of the factors influencing their abundance. PMID:22516512

  18. Impact of erosion and accretion on the distribution of enterococci in beach sands

    PubMed Central

    Gast, Rebecca J.; Gorrell, Levi; Raubenheimer, Britt; Elgar, Steve

    2011-01-01

    Bacterial pathogens in coastal sediments may pose a health risk to users of beaches. Although recent work shows that beach sands harbor both indicator bacteria and potential pathogens, it is not known how deep within beach sands the organisms may persist nor if they may be exposed during natural physical processes. In this study, sand cores of approximately 1 m depth were collected at three sites across the beach face in Kitty Hawk, North Carolina before, during and after large waves from an offshore hurricane. The presence of DNA from the fecal indicator bacterium Enterococci was detected in subsamples at different depths within the cores by PCR amplification. Erosion and accretion of beach sand at the three sites also was determined for each sampling day. The results indicate that ocean beach sands with persisting enterococci signals could be exposed and redistributed when wind, waves, and currents cause beach erosion or accretion. PMID:21984862

  19. Pro-Environmental Beach Driving is Uncommon and Ineffective in Reducing Disturbance to Beach-Dwelling Birds

    NASA Astrophysics Data System (ADS)

    Weston, Michael A.; Schlacher, Thomas A.; Lynn, David

    2014-05-01

    Vehicles on beaches cause numerous deleterious effects to coastal wildlife. These impacts may, hypothetically, be lessened if drivers act to reduce disturbance. Since it is unknown to what extent such behavior occurs, and whether it can reduce disturbance, we quantified the behavior of drivers who encountered birds on open-coast, sandy beaches in eastern Australia and the consequent bird responses. Drivers of commercial tourist buses never slowed or altered course ("evaded birds") to avoid disturbing birds; conversely, 34 % of drivers of private cars did evade birds. Drivers of vehicles with fishing rod holders tended ( P = 0.09) to evade birds more frequently than non-fishing vehicles. Evasion, when it occurred, was modest, and did not significantly decrease the intensity of bird response or the probability of escapes on the wing. Voluntary behavioral adjustments to alleviate impacts on wildlife may be unworkable, suggesting that other solutions (e.g., beach closures) might be the only effective and feasible way to reduce disturbance to birds on ocean beaches.

  20. Water Quality, Weather and Environmental Factors Associated with Fecal Indicator Organism Density in Beach Sand at Two Recreational Marine Beaches

    EPA Science Inventory

    Recent studies showing an association between fecal indicator organisms (FIOs and gastrointestinal (GI) illness among beachgoers wit sand contact have important public health implicatons because of the large numbers of people who recreate at beaches and engage in sand contact act...

  1. Stability of a very coarse-grained beach at Carmel, California

    USGS Publications Warehouse

    Dingler, J.R.

    1981-01-01

    Monastery Beach at Carmel, California, is a pocket beach composed of very coarse to granular sediment. In profile, the beach has a well-defined berm crest; a steep foreshore; and a gently sloping, barless offshore covered by large, long-crested oscillation ripples. Carmel Submarine Canyon heads a few hundred meters offshore of the beach, and San Jose Creek, a small ephemeral steam, ponds onshore of the central part of the berm. Wave conditions vary greatly during a year because the beach lies open to the Pacific Ocean for azimuths between 270??-322??N whence come a variety of wave types. Even with a variable wave climate, Monastery Beach has maintained a swell profile for almost three years. Aperiodic beach surveys show that the beach responds little to seasonal changes in wave climate. Four survey lines maintained the same swell profile throughout the study period. The fifth line maintained a stable profile only across the foreshore; the berm was twice artificially breached during storms to prevent upstream flooding along San Jose Creek. In comparison, Carmel Beach, a nearby beach composed of medium sand, commonly alternates between swell and storm profiles. The increased stability of Monastery Beach relative to Carmel Beach is attributed to two factors: grain size differences and location within Carmel Bay. Rebuilding proceeded very slowly along the breached part of the berm at Monastery Beach. The probable cause of such a low recovery rate is that oscillation ripples trapped the sand that was carried offshore when San Jose Creek eroded the beach. The ripples, which are active under high-energy conditions, approach dormancy under low-energy conditions. Each ripple, therefore, acts like a reservoir, retaining sand during most swell conditions. ?? 1981.

  2. Source discrimination of fine-grained deposits occurring on marine beaches: The Calvados beaches (eastern Bay of the Seine, France)

    NASA Astrophysics Data System (ADS)

    Dubrulle, C.; Lesueur, P.; Boust, D.; Dugué, O.; Poupinet, N.; Lafite, R.

    2007-03-01

    In tide-dominated systems, fine-grained deposits occur in intertidal areas of inner estuaries as loci of convergence of fluvial and marine material. Even in the vicinity of estuaries, mud deposits are rare on open sandy beaches. This study focuses on temporary occurrences of muddy sediments on marine beaches along the Calvados coastline in Normandy, adjacent to the macrotidal Seine estuary (France). Clay mineralogy, major-minor-trace elements and radionuclides were used as particulate markers to determine the provenance of the mud deposits. The fine fraction, defined here as particles <50 ?m, was analysed, in surficial muddy sediments on seven beaches between the Seine estuary and the Orne river mouth, sampled between February 2002 and June 2003. The deposits were compared to earlier Holocene relict deposits, which crop out on some beaches and on the shoreface, and to Mesozoic marls and limestones, which have detached from the coastal cliffs. The use of the three types of particulate markers revealed no significant seasonal or geographical variations between the beaches. The muddy deposits were made up of the same sedimentary pool of particles. The clay mineralogical and geochemical characteristics of these mud deposits enabled modern (i.e. present-day and earlier Holocene fine silts and clays) to be distinguished from ancient (i.e. Mesozoic) sediments. The use of radionuclides ( 60Co and 137Cs) confirmed the marine influence in the modern deposits, with a decreasing gradient along the Calvados beaches towards the east. The presence of several specific major-minor-trace elements (e.g. Ti, P) revealed that some of the fine material originated in the Seine estuary. Despite the occurrence of easily erodable rocks (i.e. clays, marls and limestones) in the coastal cliffs, this source represented a limited supply, which is only of local significance. Small rivers, such as the Orne, Dives and Touques which discharge in the study area act as secondary suppliers of fine-grained material to this system. In spite of the exposed coastal setting where strong tidal currents and waves occur, the beaches have become a distal part of the Seine estuarine system and form a temporary sink for strongly mixed fine material mainly of riverine (Seine River) and open marine (Bay of the Seine and the Central English Channel) origins. This is consistent with the infilling of the estuary, the reduction in accommodation space in its inner part, and the offshore shifting of the depocentre of the mud.

  3. Storm recovery on two Italian coarse-grained beaches: a comparison between a mixed sand and gravel and a pebble beach

    NASA Astrophysics Data System (ADS)

    Bertoni, Duccio; Grottoli, Edoardo; Ciavola, Paolo; Sarti, Giovanni; Pozzebon, Alessandro

    2014-05-01

    High energy events emphasize beach erosion processes, sometimes leading to huge volume deficits not balanced by recovery under fair-weather conditions. In this scenario, artificial replenishments are frequently used as a form of coastal protection with large volumes of sediments re-injected in the system without strongly altering the environment as it happens with hard structures. Since climate change is expected to accentuate in the near future erosion effects, the need to artificially feed beaches is likely to increase. Gravel and pebbles are more and more often used as beach fill, on some occasions replacing sandy sediments. That was the case for two beaches located at either sides of the Italian Peninsula (Portonovo, Adriatic Sea; Marina di Pisa, Ligurian Sea), which constitute the study area of the present research. Portonovo is a 500 m-long mixed sand and gravel beach with a significant pebble-sized content (about 40%), unloaded on the beach during multiple replenishments. Marina di Pisa is an artificial, 180 m-long beach, mainly composed of 40-to-90 mm pebbles; it was built in 2008 as a part of a larger protection scheme. Groins or headlands that prevent any sediment exchange with adjacent areas bound both beaches. Periodic topographic surveys were carried out to evaluate the response of these human-altered beaches to high-energy events. The topographic surveys, undertaken with a DGPS-RTK instrument along cross-shore transects (from the landward end of the backshore to about 1.5 m depth seaward), were done following intense storm events occurred during the time period of the research. Transects were done out every 10 m along the entire length of the beaches. Prior to the first topographic survey, a sediment tracing experiment was set up as a form of control of the results provided by the geomorphologic analysis. Pebbles directly sampled from the beaches were marked by means of the RFID technology and injected back all along the beachface. As expected, considerable beach profile changes after the storms were identified, in particular at Portonovo (mixed beach), where huge sediment volumes were displaced longshore according to the incident wave direction as opposed to Marina di Pisa (gravel dominated), where the main beach changes developed along the cross-shore direction. In terms of resilience, results showed a better response of the Portonovo beach rather than the Marina di Pisa beach. The different response might be ascribed to the grain-size that constitutes the beaches: no physical process can rework the pebbles at Marina di Pisa once they are moved during the storms towards the back-end of the backshore or seaward of the step, thus preventing any beach recovery process to take place. Since the awareness on storm impacts is more critical than in the past, the understanding of beach recovery to extreme events needs new insights to combine the preservation of natural beach evolution as well as maintenance for end-users. That is particularly pressing on coarse-grained beaches, where the need to predict storm impact and recovery is much more vital considering that finding suitable sediment to refill the beach is never an easy task.

  4. Climate-change impacts on sandy-beach biota: crossing a line in the sand.

    PubMed

    Schoeman, David S; Schlacher, Thomas A; Defeo, Omar

    2014-08-01

    Sandy ocean beaches are iconic assets that provide irreplaceable ecosystem services to society. Despite their great socioeconomic importance, beaches as ecosystems are severely under-represented in the literature on climate-change ecology. Here, we redress this imbalance by examining whether beach biota have been observed to respond to recent climate change in ways that are consistent with expectations under climate change. We base our assessments on evidence coming from case studies on beach invertebrates in South America and on sea turtles globally. Surprisingly, we find that observational evidence for climate-change responses in beach biota is more convincing for invertebrates than for highly charismatic turtles. This asymmetry is paradoxical given the better theoretical understanding of the mechanisms by which turtles are likely to respond to changes in climate. Regardless of this disparity, knowledge of the unique attributes of beach systems can complement our detection of climate-change impacts on sandy-shore invertebrates to add rigor to studies of climate-change ecology for sandy beaches. To this end, we combine theory from beach ecology and climate-change ecology to put forward a suite of predictive hypotheses regarding climate impacts on beaches and to suggest ways that these can be tested. Addressing these hypotheses could significantly advance both beach and climate-change ecology, thereby progressing understanding of how future climate change will impact coastal ecosystems more generally. PMID:25121188

  5. On the profile evolution of three artificial pebble beaches at Marina di Pisa, Italy

    NASA Astrophysics Data System (ADS)

    Bertoni, Duccio; Sarti, Giovanni

    2011-07-01

    In this paper, the profiles of three artificial coarse-grained beaches located at Marina di Pisa (Tuscany, Italy) were monitored from April 2008 to May 2009 in order to define the response of the beaches to major storms that occurred during the study. Two beaches are similar, the third differs in length and in the level of protection, being less than half the length of the others and devoid of an offshore submerged breakwater. The work was achieved by means of accurate topographic surveys intended to reconstruct the beach profile from the backshore up to the foreshore-upper shoreface transition (step). The surveys were performed with an RTK-GPS instrument, which provided extremely precise recording of the beach. The most significant features of the beaches were tracked during each survey; in particular, the landward foot of the storm berm, the crest of the storm berm, the coastline, and the step crest were monitored. Five cross-shore transects were traced on each beach. Along these transects, any meaningful slope change was recorded to obtain accurate sections of the beach. The field datasets were processed with AutoCAD software to compare the beach profile evolution during the year-long research. The results showed a comparable evolution of the twin beaches: the resulting storm berm retreat of about 15 to 19 m is a remarkable feature considering the coarse grain size and the offshore protection. Due to the absence of the breakwater, the third beach was characterized by even higher values of recession (over 20 m), and showed hints of wave reflection-related processes after the huge, steep storm berm had been formed and grown after the high energy events. These processes were not as evident on the twin beaches. These results underline the different response of three similar protection schemes, and the importance that frequent monitoring of the beach morphology holds when it comes to coastal management issues.

  6. Deep-sea isopod biodiversity, abundance, and endemism in the Atlantic sector of the Southern Ocean—Results from the ANDEEP I III expeditions

    NASA Astrophysics Data System (ADS)

    Brandt, Angelika; Brix, Saskia; Brökeland, Wiebke; Choudhury, Madhumita; Kaiser, Stefanie; Malyutina, Marina

    2007-08-01

    Three expeditions were performed in the framework of ANDEEP (ANtarctic benthic DEEP-sea biodiversity, colonisation history and recent community patterns) in order to understand the Southern Ocean (SO) biodiversity of the Isopoda and to investigate faunal connections with other deep-sea areas in the world oceans. We sampled mainly in the Atlantic sector of the SO (Drake Passage along the Shackleton Fracture Zone, off Elephant Island, in the South Shetland Islands area, in the northwestern Weddell Sea, and at the South Sandwich Islands), but also took two stations in each Bellingshausen Sea and Cape Basin. In total, three expeditions yielded 13,046 specimens of Isopoda. During ANDEEP I-II 5525 specimens and 317 species of Isopoda were sampled, and 7521 specimens and 496 species were discriminated from the ANDEEP III material. Overall, Isopoda comprised 35% of all Peracarida sampled, and we identified 674 isopod species from the 40 deep SO stations. Eighty-nine of these species (13%) were known, the others (585 species) were new to the area, and most of these were new to science, 43 genera being recorded for the first time. Asellota comprised 97% of all ANDEEP Isopoda, and Munnopsidae were the most dominant family, followed by the Desmosomatidae, Haploniscidae, and Ischnomesidae. To our present knowledge 87% of the SO deep-sea Isopoda are apparently "endemic". Most species did not occur frequently in the samples. Abundance was higher at the shallower ANDEEP stations and highest in the Powell Basin at station 133, and generally decreased with increasing depth. Species richness was highest with 92 species at the bathyal station 80-9 in 3100 m off Kapp Norvegia, in general, species richness was highest at around 3000 m depth with 216 species found at all ANDEEP stations, and 92 species sampled at a single station in 3100 m depth. The cluster analysis of the isopod composition from ANDEEP revealed in general terms that the abyssal Weddell-Sea stations build one cluster. Depth turned out to be the most important abiotic factor for the species composition reported. Most of the species frequently occurring at the abyssal stations are Munnopsidae, which can swim. The SO deep sea differs in faunal composition from the shelf, and few isopod species occur at many stations, while most species only occur at few. The reasons for these findings are unknown. Future studies should focus on the functional role of the frequent species of the SO deep-sea ecosystem and food-web.

  7. Documenting the global impacts of beach sand mining

    NASA Astrophysics Data System (ADS)

    Young, R.; Griffith, A.

    2009-04-01

    For centuries, beach sand has been mined for use as aggregate in concrete, for heavy minerals, and for construction fill. The global extent and impact of this phenomenon has gone relatively unnoticed by academics, NGOs, and major news sources. Most reports of sand mining activities are found at the very local scale (if the mining is ever documented at all). Yet, sand mining in many localities has resulted in the complete destruction of beach (and related) ecosystems along with severe impacts to coastal protection and tourism. The Program for the Study of Developed Shorelines at Western Carolina University and Beachcare.org have initiated the construction of a global database of beach sand mining activities. The database is being built through a combination of site visits and through the data mining of media resources, peer reviewed papers, and reports from private and governmental entities. Currently, we have documented sand mining in 35 countries on 6 continents representing the removal of millions of cubic meters of sand. Problems extend from Asia where critical infrastructure has been disrupted by sand mining to the Caribbean where policy reform has swiftly followed a highly publicized theft of sand. The Program for the Study of Developed Shorelines recently observed extensive sand mining in Morocco at the regional scale. Tens of kilometers of beach have been stripped of sand and the mining continues southward reducing hope of a thriving tourism-based economy. Problems caused by beach sand mining include: destruction of natural beaches and the ecosystems they protect (e.g. dunes, wetlands), habitat loss for globally important species (e.g. turtles, shorebirds), destruction of nearshore marine ecosystems, increased shoreline erosion rates, reduced protection from storms, tsunamis, and wave events, and economic losses through tourist abandonment and loss of coastal aesthetics. The threats posed by sand mining are made even more critical given the prospect of a significant rise in global sea level over the coming decades. Most governments recognize the local impacts of sand mining and mining activities are illegal in many localities. However, enforcement of these protections has been problematic and there has been little pressure to stop the practice from local or international environmental groups. In many cases, addressing the issue of sand mining requires addressing the local issues that allow it to persist. This includes poverty, corruption, and unregulated development. In areas where beach sand mining significantly supports the local economy, care needs to be given that local workers are given alternative means of income, and builders are provided an affordable substitute for the sand (e.g. crushed rock). Regardless, it is time for both academics and NGOs to address the cumulative environmental impacts of the direct destruction of the world's beaches through mining activities.

  8. Modes and emergent time scales of embayed beach dynamics

    NASA Astrophysics Data System (ADS)

    Ratliff, Katherine M.; Murray, A. Brad

    2014-10-01

    In this study, we use a simple numerical model (the Coastline Evolution Model) to explore alongshore transport-driven shoreline dynamics within generalized embayed beaches (neglecting cross-shore effects). Using principal component analysis (PCA), we identify two primary orthogonal modes of shoreline behavior that describe shoreline variation about its unchanging mean position: the rotation mode, which has been previously identified and describes changes in the mean shoreline orientation, and a newly identified breathing mode, which represents changes in shoreline curvature. Wavelet analysis of the PCA mode time series reveals characteristic time scales of these modes (typically years to decades) that emerge within even a statistically constant white-noise wave climate (without changes in external forcing), suggesting that these time scales can arise from internal system dynamics. The time scales of both modes increase linearly with shoreface depth, suggesting that the embayed beach sediment transport dynamics exhibit a diffusive scaling.

  9. Shorebird use of an exposed sandy beach in southern California

    NASA Astrophysics Data System (ADS)

    Hubbard, David M.; Dugan, Jenifer E.

    2003-10-01

    Frequent morning surveys of birds were conducted on 1 km of beach in southern California to investigate shorebird use of an exposed sandy beach. The overall mean abundance (98.6 individuals km -1), estimated biomass (9.6 kg km -1), and species richness (5.5 species km -1) of shorebirds observed were very high for a sandy beach in the temperate zone. Eight species, sanderling ( Calidris alba), semipalmated plover ( Charadrius semipalmatus), marbled godwit ( Limosa fedoa), black-bellied plover ( Pluvialis squatarola), western sandpiper ( Calidris mauri), willet ( Catoptrophorus semipalmatus), surfbird ( Aphriza virgata), and whimbrel ( Numenius phaeopus), occurred in overall mean abundances >1 bird km -1 and accounted for 97% of the abundance and biomass of shorebirds. Sanderlings were the most abundant shorebird every year (64% of individuals and 35% of the biomass). Different species of abundant shorebirds exhibited distinct patterns of use of beach habitat, including fall, spring, and winter peaks in abundance. Temporal variation in shorebird use on seasonal and interannual scales was associated with migration patterns, and also with habitat availability and condition. Seasonal variation in monthly mean abundance and estimated biomass of shorebirds varied over more than an order of magnitude and followed a similar pattern in each year, reaching maxima in the fall or winter (161-280 individuals km -1 and 15.4-23.9 kg km -1) and minima in May or June (3-11 individuals km -1 and 0.8-2.2 kg km -1). A minor peak in shorebird abundance and biomass coinciding with spring migration was observed in April of most years. The number of species of shorebirds observed in individual surveys ranged from 0 to 11 species km -1 and was positively and significantly correlated with abundance. Monthly mean species richness and the total species observed monthly followed similar seasonal patterns, ranging from annual maxima of 7.4-9.1 and 12-17 species km -1 between August and October to minima of 0.8-2.1 and 2-8 species km -1, respectively, during June. In contrast, species turnover was lowest (1.1-1.7) in October and November, and generally highest (2-4) during early summer (June). The amount of sandy intertidal habitat available to shorebirds on the transect was estimated using sand elevations and predicted tide heights. In the fall and winter, the abundance of shorebirds was significantly and positively correlated with tide height, possibly reflecting feeding opportunities and high tide refuge effects during the highest tides. In the spring when sand levels were low, the abundance of shorebirds was negatively correlated with tide height. Prey availability, beach condition and the local availability, and condition of alternative foraging habitats may influence those relationships. Interannual variations in shorebird use and beach condition were observed in the course of the study. During an El Nino Southern Oscillation (ENSO) event (1997-1998), the extent of sandy habitat was greatly reduced and intertidal habitat was mostly converted to rocky substrate. The overall abundance of shorebirds and the mean abundance of some common species (e.g. sanderling) were depressed, and an uncommon species (surfbird, A. virgata) was unusually abundant during the ENSO event. In summary, the results suggest that sandy beaches are important habitat for many species of shorebirds, particularly in areas where alternative coastal foraging habitats, such as coastal wetlands, have become scarce. Understanding the dynamics of and threats to exposed sandy beaches may be increasingly important for shorebird conservation in many coastal regions.

  10. Achieving Energy Savings in Municipal Construction in Long Beach California

    SciTech Connect

    2013-03-01

    Long Beach Gas and Oil (LBGO), the public gas utility in Long Beach, California, partnered with the U.S. Department of Energy (DOE) to develop and implement solutions to build a new, low-energy modular office building that is at least 50% below requirements set by Energy Standard 90.1-2007 of the American Society of Heating, Refrigerating, and Air-conditioning Engineers (ASHRAE), the American National Standards Institute (ANSI), and the Illuminating Engineering Society of America (IESNA) as part of DOE’s Commercial Building Partnerships (CBP) program. The LBGO building, which demonstrates that modular construction can be very energy efficient, is expected to exceed the ASHRAE baseline by about 45%.

  11. Regional beach/cliff system dynamics along the california coast

    USGS Publications Warehouse

    Hapke, C.J.; Reid, Don

    2007-01-01

    The coast of California is comprised of both sandy shorelines and cliffed coastline, and in many areas these features spatially coincide. In order to better understand the regional trends of change along the California coast, the U.S. Geological Survey is quantifying both sandy shoreline change and coastal cliff retreat for the state. The resulting database was used to examine the dynamics of the beach/cliff system. We found inconsistent evidence of a relationship between rates of cliff retreat and shoreline change on the spatial scale of 100-km cells. However, when the data are correlated within individual regions, a strong relationship exists between the geomorphology of the coast and the behavior of the beach/cliff system. Areas of high-relief coast show negative correlations, indicating that higher rates of cliff retreat correlate with lower rates of shoreline erosion. In contrast, low- to moderate-relief coasts show strong positive correlations.

  12. Identifying Preserved Storm Events on Beaches from Trenches and Cores

    NASA Astrophysics Data System (ADS)

    Wadman, H. M.; Gallagher, E. L.; McNinch, J.; Reniers, A.; Koktas, M.

    2014-12-01

    Recent research suggests that even small scale variations in grain size in the shallow stratigraphy of sandy beaches can significantly influence large-scale morphology change. However, few quantitative studies of variations in shallow stratigraphic layers, as differentiated by variations in mean grain size, have been conducted, in no small part due to the difficulty of collecting undisturbed sediment cores in the energetic lower beach and swash zone. Due to this lack of quantitative stratigraphic grain size data, most coastal morphology models assume that uniform grain sizes dominate sandy beaches, allowing for little to no temporal or spatial variations in grain size heterogeneity. In a first-order attempt to quantify small-scale, temporal and spatial variations in beach stratigraphy, thirty-five vibracores were collected at the USACE Field Research Facility (FRF), Duck, NC, in March-April of 2014 using the FRF's Coastal Research and Amphibious Buggy (CRAB). Vibracores were collected at set locations along a cross-shore profile from the toe of the dune to a water depth of ~1m in the surf zone. Vibracores were repeatedly collected from the same locations throughout a tidal cycle, as well as pre- and post a nor'easter event. In addition, two ~1.5m deep trenches were dug in the cross-shore and along-shore directions (each ~14m in length) after coring was completed to allow better interpretation of the stratigraphic sequences observed in the vibracores. The elevations of coherent stratigraphic layers, as revealed in vibracore-based fence diagrams and trench data, are used to relate specific observed stratigraphic sequences to individual storm events observed at the FRF. These data provide a first-order, quantitative examination of the small-scale temporal and spatial variability of shallow grain size along an open, sandy coastline. The data will be used to refine morphological model predictions to include variations in grain size and associated shallow stratigraphy.

  13. Edge capillary-gravity waves on a sloping beach

    NASA Astrophysics Data System (ADS)

    Muzylev, Sergey V.; Bulgakov, Sergey N.; Duran-Matute, Matias

    2005-04-01

    It is shown how the solution for velocity potential may be determined when the effect of surface tension is included in the linearized theory of Ursell-type edge waves over a plane-sloping beach. The problem is examined without making a hydrostatic assumption. Explicit solutions for edge capillary-gravity waves are given and the dispersion equation is obtained. The influence of capillarity on gravity waves is discussed.

  14. Modeling the Economics of Beach Nourishment Decisions in Response to Coastal Erosion

    NASA Astrophysics Data System (ADS)

    Ware, M.; Ashton, A. D.; Hoagland, P.; Jin, D.; Kite-Powell, H.; Lorenzo-Trueba, J.

    2012-12-01

    Beaches are constantly moving and changing. The dynamic transformations of beaches are mostly the result of the erosion of sand, which can occur through movements alongshore caused by waves, movements off-shore due to storms, or submersion due to sea-level rise. Predicted climate change impacts include potential changes in storminess and accelerated sea-level rise, which will lead to increased coastal erosion. At the same time, the number of people residing in coastal communities is increasing. The risks from eroding beaches (increased coastal flooding, damage to infrastructure, and displaced residents) are therefore increasing in number and scale; and coastal residents are taking actions to protect their homes. One such action is beach nourishment, where sand is added to a resident's property in order to widen the beach. We have developed an economic model of beach nourishment decision-making to investigate the relationship between the optimal volume and timing of beach nourishment and factors such as property value, erosion rate, and initial beach width. In this model, waterfront property owners nourish a beach when the losses in net rental income exceed the costs incurred from nourishing the beach. (Rental income is a function of property value, which in turn depends upon the width of the beach.) It is assumed that erosion and sea-level rise are related. We examine different nourishment scenarios, including one-time nourishment in the first year; constant annual nourishment; and a myopic decision process in which the homeowner nourishes the beach if property losses from erosion over the next five years are expected to exceed the cost of nourishment. One-time nourishment delays property flooding for both constant and accelerating sea level rise; however, this delay is more substantial under constant sea level rise. With continual nourishment, the beach can be maintained under constant sea-level rise, provided that the erosion rate is comparable to the additional width from nourishment each year. In contrast, for practical nourishment volumes, erosion from accelerating sea-level rise eventually out-competes beach nourishment and inundation occurs. Under the myopic decision-making model, with both constant and accelerating sea-level rise, nourishment does not take place until a property is critically endangered. The beach slope, nourishment volume, property value, and initial beach width all are found to be important factors in determining when nourishment should start and how frequently it should occur thereafter. These models can be used by policy-makers to formulate better coastal management policies, by coastal geologists to understand human impacts on beach dynamics, and by the insurance industry to realistically anticipate human risk-taking and decision-making.

  15. Marine macrophytes directly enhance abundances of sandy beach fauna through provision of food and habitat

    NASA Astrophysics Data System (ADS)

    Ince, Rebecca; Hyndes, Glenn A.; Lavery, Paul S.; Vanderklift, Mathew A.

    2007-08-01

    Beach-cast wrack is a prominent feature of beaches of south-western Australia. We examined the fauna of these beaches to explore the generalisation [Polis, G.A., Hurd, S.D., 1995. Extraordinarily high spider densities on islands: flow of energy from the marine to terrestrial food webs and the absence of predation. Ecology 92, 4382-4386] that beach-cast wrack from highly productive marine ecosystems subsidises low productivity of terrestrial ecosystems, to establish whether this generalisation is relevant to oligotrophic marine systems. We sampled three beaches with high and three beaches with low volumes of beach-cast wrack to determine if: (1) the presence of wrack influences the abundance of macroinvertebrates; (2) wrack acts as a food source for beach macroinvertebrates; and (3) the influence of wrack varies between zones above the high water mark. We measured wrack volume and composition, sediment characteristics, the abundance of different epibenthic and infaunal macroinvertebrates taxa, and ?13C and ?15N of macrophytes and macroinvertebrates. The mean volume of wrack on high-wrack beaches was 0.27-1.07 m 3 wrack m -2 compared to 0.00-0.09 m 3 wrack m -2 on low-wrack beaches. There were no significant differences in sediment grain size, moisture content or loss on ignition between the two types of beaches or zones. Epibenthic fauna and infauna were consistently abundant on high-wrack beaches (20-291 and 0.5-3.5 individuals 0.64 m -2, respectively), but either absent or extremely rare in low-wrack beaches (0-3 and 0-0.1 individuals 0.64 m -2, respectively). Within high-wrack beaches, there were no significant differences in the abundance of epifauna or infauna among beaches or between zones. The ?13C values of macroinvertebrates at all sites were most similar to red and brown algae, with the exception of beetles from two beaches, which were closest to seagrasses. Mixing model (Isosource) results for mesograzing amphipods and dipteran flies suggested carbon was assimilated mostly from the seagrass Posidonia spp., the dune grass Spinifex longifolia and red algae for amphipods and from brown algae, red algae and dune vegetation for dipteran flies. We conclude that the presence of marine-derived wrack plays a major role in subsidising production of macroinvertebrates on beaches of south-western Australia. We suggest that marine subsidies can play a role in supporting terrestrial production, even in oligotrophic marine environments.

  16. Assessment of tar pollution on the United Arab emirates beaches

    SciTech Connect

    Abu-Hilal, A.H.; Khordagui, H.K. )

    1993-01-01

    In light of the inadequate information concerning stranded tar on the southwest beaches of the Arabian Gulf and the Gulf of Oman, particularly following the massive oil releases during the Gulf War, the present investigation was designed to provide reference-integrated information on the nature, location, and levels of stranded tar balls on the beaches of the United Arab Emirates (UAE). The recorded levels appeared to be higher than expected or previously reported. The tar distribution pattern, in addition to the degree of weathering, indicates that the massive oil release during the Gulf War did not reach the UAE shorelines. The highest reported levels of stranded tar ever recorded in the Arabian Gulf at Jabal Dhannah apparently originated from oil spills and tankers' ballast water at the main oil terminal at the Al-Ruwaiss oil refinery some 10 km to the east. The surprising, relatively high levels of stranded tar on the beaches of the Gulf of Oman were solely attributed to the heavy navigation traffic close to the shorelines. 19 refs., 2 figs., 3 tabs.

  17. Microbial Load from Animal Feces at a Recreational Beach

    PubMed Central

    Wright, Mary E.; Solo-Gabriele, Helena M.; Elmir, Samir; Fleming, Lora E.

    2009-01-01

    The goal of this study was to quantify the microbial load (enterococci) contributed by the different animals that frequent a beach site. The highest enterococci concentrations were observed in dog feces with average levels of 7.4 × 106 CFU/g; the next highest enterococci levels were observed in birds averaging 3.3 × 105 CFU/g. The lowest measured levels of enterococci were observed in material collected from shrimp fecal mounds (2.0 CFU/g). A comparison of the microbial loads showed that 1 dog fecal event was equivalent to 6,940 bird fecal events or 3.2 × 108 shrimp fecal mounds. Comparing animal contributions to previously published numbers for human bather shedding indicates that one adult human swimmer contributes approximately the same microbial load as one bird fecal event. Given the abundance of animals observed on the beach, this study suggests that dogs are the largest contributing animal source of enterococci to the beach site. PMID:19664785

  18. Geochemistry of beach sands from Sithonia Peninsula (Chalkidiki, Northern Greece)

    NASA Astrophysics Data System (ADS)

    Papadopoulos, A.; Christofides, G.; Pe-Piper, G.; Koroneos, A.; Papadopoulou, L.

    2015-02-01

    Thirty beach sand samples from the granitic shoreline of the Sithonia Plutonic Complex (SPC) were analyzed for their REE and major element contents. The obtained results are compared with the adjacent SPC rock-types, in order to determine any enrichments or depletions. Among the samples enriched in REE, three are seasonal deposits of heavy minerals and their concentrations are controlled by the action of sea-waves. The available geochemical characteristics were also used to confirm the parental rocks of the beach sands, which are the SPC rock-types. The heavy fractions (total, total magnetic and total non-magnetic) of the beach sands were correlated with the REE concentrations, revealing a strong correlation between the heavy non-magnetic fraction and REE content. Among the minerals of the heavy non-magnetic fraction, monazite seems to control the REE content in the heavy mineral-enriched samples, whereas in the rest of the samples allanite, belonging to the heavy magnetic fraction may be the most important REE mineral.

  19. Neogene diatom and silicoflagellate biostratigraphy of Naples Beach, California

    SciTech Connect

    Navarrette, R.J.; Marolt, R.E.; Finger, K.L.

    1986-04-01

    Diatoms and silicoflagellates recovered from Monterey Formation outcrops along Naples Beach, California, provide detailed biostratigraphy in the middle Miocene to upper Pliocene strata. Thirty-eight diatom and six silicoflagellate index species are identified among the 178 selected taxa documented in this section. Seven diatom zones and subzones of J. Barron's northeastern Pacific diatom zonation are recognized in this section. These zones range from the Denticulopsis lauta subzone a (+15.0 m.y.) to the base of the Thalasiosira oestrupii zone (approx. 5.0 m.y.). In addition, several diatom occurrences provide direction correlation between the Naples Beach section and DSDP Sites 173 and 469 off the northern and southern California coasts, respectively. A new silicoflagellate zonation is proposed for the Naples Beach section of the Monterey Formation, which consists of two range zones, the Corbisema triacantha and the Distephanus speculum minutus, and four subzones. These four subzones are characterized by Distephanus crux parvus, Mesocena diodon, Distephanus pseudofibula, and Distephanus frugalis, respectively. This zonation provides greater precision than previous biostratigraphic divisions of the DSDP sites. A new silicoflagellate species of the genus Dictyocha Ehrenberg is also described.

  20. Microplastic resin pellets on an urban tropical beach in Colombia.

    PubMed

    Acosta-Coley, Isabel; Olivero-Verbel, Jesus

    2015-07-01

    Microplastics are a problem in oceans worldwide. The current situation in Latin America is not well known. This paper reports, for the first time, the presence of microplastics on an urban Caribbean beach in Cartagena, Colombia. Pellet samples were collected from a tourist beach over a 5-month period covering both dry and rainy seasons. Pellets were classified by color and their surface analyzed by stereomicroscopy, and some were characterized by infrared spectroscopy. The most abundant pellets were white, presenting virgin surfaces, with few signs of oxidation. This is congruent with a short residence time in the marine environment and primary sources possibly located nearby. The frequency of white pellets did not change with sampling period. Surface features identified in the pellets included cracks, material loss, erosion, adhesion, granulation, color change, and glazed surfaces. Reticulated granular pellets exhibited the greatest degradation, easily generating submicroplastics. Sample composition was mostly polyethylene, followed by polypropylene. This pollution problem must be addressed by responsible authorities to avoid pellet deposition in oceans and on beaches around the world. PMID:26082422