Artículos de revistas: "Sandy beaches, littoral macrofauna"

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Petracco, Marcelo, Ricardo Silva Cardoso y Alexander Turra. "Patterns of sandy-beach macrofauna production". Journal of the Marine Biological Association of the United Kingdom 93, n.º 7 (8 de abril de 2013): 1717–25. http://dx.doi.org/10.1017/s0025315413000246.

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Using data available from the literature, patterns of biomass, production and productivity of sandy-beach macrofauna populations were examined, considering environmental (temperature, exposure, grain size and beach slope) and biological variables (life span and mean body mass) and feeding and taxonomic groups. A total of 102 estimates of both production and biomass and 105 estimates of P/B ratios were collected from 52 studies carried out between 42°46′S and 54°05′N, for 83 sandy-beach macrofauna populations. The negative relationship between P/B ratio and beach slope for the supralittoral amphipods agrees with the Habitat Safety Hypothesis, according to which these forms would show higher mortality in dissipative than in reflective beaches. The observed higher production of filter-feeders in exposed than in sheltered beaches suggests that more food is available for filter-feeders in exposed beaches. The higher production of filter-feeders (represented by bivalves and decapods), than of scavengers/predators (peracarids and gastropods) showed the importance of filter-feeders in the food web of sandy beaches. The P/B ratios were strongly related to life span, but weakly or not related to the mean body mass. The high amphipod P/B ratio was attributed to the short life span of these crustaceans; conversely, gastropods showed the lowest P/B ratio, in accordance with their longer life span. The observed differences in biomass, production and P/B ratios within crustaceans and molluscs were attributed to differences in life-history traits and feeding mode.

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Costa, Leonardo Lopes, Phillipe Mota Machado y Ilana Rosental Zalmon. "Do natural disturbances have significant effects on sandy beach macrofauna of Southeastern Brazil?" Zoologia 36 (31 de julio de 2019): 1–10. http://dx.doi.org/10.3897/zoologia.36.e29814.

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The role of morphodynamic features such as grain size, swash climate and wave action on the macrofauna of beaches are well-known. However, few studies have investigated natural disturbances as potential drivers of temporal community variations. In southeastern Brazil, we sampled the intertidal macrofauna of two sandy beaches to test whether seasonal disturbances as the frequency of storm wave events (SWE) and rainfall have significant influence on their composition and abundance. The macrofauna assemblage differed significantly between the rainy and the dry seasons, but rainfall was not the main driver of community changes, although both beaches are in the vicinity of extensive river plumes. Actually, SWE explained most macrofauna richness overtime, with positive effects. Our results point to the importance of learning more about the effects of poorly studied disturbances on macrofaunal communities, and based on them we strongly recommend including these seasonal phenomena when monitoring sandy beaches.

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Ferreira, Giulianne Sampaio, Danilo Augusto Almeida dos Santos y Edson Varga Lopes. "Richness, abundance and microhabitat use by Ardeidae (Aves: Pelecaniformes) during one seasonal cycle in the floodplain lakesof the lower Amazon River". Zoologia 36 (31 de julio de 2019): 1–9. http://dx.doi.org/10.3897/zoologia.36.e30475.

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The role of morphodynamic features such as grain size, swash climate and wave action on the macrofauna of beaches are well-known. However, few studies have investigated natural disturbances as potential drivers of temporal community variations. In southeastern Brazil, we sampled the intertidal macrofauna of two sandy beaches to test whether seasonal disturbances as the frequency of storm wave events (SWE) and rainfall have significant influence on their composition and abundance. The macrofauna assemblage differed significantly between the rainy and the dry seasons, but rainfall was not the main driver of community changes, although both beaches are in the vicinity of extensive river plumes. Actually, SWE explained most macrofauna richness overtime, with positive effects. Our results point to the importance of learning more about the effects of poorly studied disturbances on macrofaunal communities, and based on them we strongly recommend including these seasonal phenomena when monitoring sandy beaches.

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4

Mattos, Gustavo, Ricardo S. Cardoso y André Souza Dos Santos. "Environmental effects on the structure of polychaete feeding guilds on the beaches of Sepetiba Bay, south-eastern Brazil". Journal of the Marine Biological Association of the United Kingdom 93, n.º 4 (14 de junio de 2012): 973–80. http://dx.doi.org/10.1017/s0025315412000707.

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Several studies have been conducted to explain patterns of the abundance, richness and diversity of sandy-beach macrofauna; however, such analyses have ignored the overall functional structure of macrofauna communities. Few studies have examined polychaete feeding guilds on sandy beach environments. To examine the effects of environmental factors on polychaete feeding guilds on sandy beaches, 12 sandy beaches from five islands in Sepetiba Bay were sampled. A total of 24 polychaete morphospecies, grouped among 21 families, were identified in these sandy beaches. The polychaete species were classified into 10 feeding guilds, and the SDT guild (suspended-deposit feeders, discretely motile, with tentacles) was the most abundant feeding guild, with 34.2% of total number of organisms. The highest trophic importance index and index of trophic diversity values were recorded on the sheltered beaches. A canonical correspondence analysis showed that the exposure rate, beach length, and grain size of the beach sediment significantly affected the polychaete feeding guild distribution and abundance. We can conclude that sheltered beaches have a higher diversity of feeding guilds than exposed beaches and that the biological descriptors of the feeding guilds are directly associated with the grain size of the sediment.

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Petracco, Marcelo, Ricardo Silva Cardoso, Thais Navajas Corbisier y Alexander Turra. "Brazilian sandy beach macrofauna production: a review". Brazilian Journal of Oceanography 60, n.º 4 (diciembre de 2012): 473–84. http://dx.doi.org/10.1590/s1679-87592012000400006.

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

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Coutinho, Mariane Silva y Angelo Fraga Bernardino. "Spatial and seasonal changes in benthic macrofauna from two dissipative sandy beaches in eastern Brazil)". Brazilian Journal of Oceanography 65, n.º 4 (diciembre de 2017): 666–77. http://dx.doi.org/10.1590/s1679-87592017115806504.

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Abstract Sandy beaches are dynamic ecosystems with strong interaction of sediments, waves and tidal energy, with marked effects on benthic assemblages. Although there are numerous efforts in understanding spatial-temporal variation of benthic macrofauna on sandy beaches along the southern and southeastern Marine Ecoregions in Brazil, there is poor sampling along beaches of the Eastern Marine Ecoregion (EME). Here we examined spatial and temporal scales of variability in benthic macrofauna (> 500 µm) through a hierarchical sampling of two dissipative sandy beaches within the EME between two seasons (winter 2011 and summer 2012). We tested the hypothesis that spatial changes (i.e., meters to hundreds of meters scales) in the structure of benthic assemblages will be more pronounced compared to the weak seasonal fluctuations at this tropical region. We found weak temporal and spatial changes in sediment grain size and beach slope, but differences in macrofaunal assemblages were evident. Contrary to our hypothesis, hierarchical sampling indicated significant changes in macrofaunal composition and density at multiple local scales (meters to hundreds of meters) and on seasonal scales. The macrofauna density and composition was directly related to changes on the sediment organic matter and grain size.

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Afghan, Afghan, Carlo Cerrano, Giorgia Luzi, Barbara Calcinai, Stefania Puce, Torcuato Pulido Mantas, Camilla Roveta y Cristina Gioia Di Camillo. "Main Anthropogenic Impacts on Benthic Macrofauna of Sandy Beaches: A Review". Journal of Marine Science and Engineering 8, n.º 6 (3 de junio de 2020): 405. http://dx.doi.org/10.3390/jmse8060405.

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Sandy beaches provide several ecosystem services such as coastal protection and resilience, water filtration and nutrient mineralization. Beaches also represent a hub for social, cultural and economic relationships as well as educational activities. Increasing urbanization, recreational activities and mechanical beach cleaning represent major anthropogenic disturbances on sandy beaches leading to loss of biodiversity as well as good and services. Information about the impacts of anthropogenic pressures on benthic macrofaunal communities could be useful to assess the environmental status of sandy beaches and to promote a sustainable use of beach ecosystem. Here, scientific articles about three major anthropogenic impacts on sandy beach macrofauna were reviewed to provide the state of knowledge about these impacts, to highlight gaps, to supply considerations about the methodologies and the used indicators and to give insights for future studies. The stressors considered in our review are: 1) trampling, 2) breakwater barriers, 3) mechanical beach cleaning. This review underlined that there are few studies regarding individual human disturbances on sandy beach macrofauna and specifically, there is a lack of sufficient indicator species for the assessment of such stressors. Similarly, the researches have covered specific regions, highlighting the need for such studies in other parts of the world. In particular, the impacts of breakwater barriers on surrounding communities has been found to be given less attention in the literature and there is enough that could be explored.

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Veloso, Valéria Gomes y Ricardo Silva Cardoso. "Effect of morphodynamics on the spatial and temporal variation of macrofauna on three sandy beaches, Rio de Janeiro State, Brazil". Journal of the Marine Biological Association of the United Kingdom 81, n.º 3 (junio de 2001): 369–75. http://dx.doi.org/10.1017/s0025315401003976.

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Three exposed sandy beaches were selected to compare fluctuations in density of the most abundant species, and to verify the influence of spatial and temporal variations on the community structure. Sampling was carried out every three months, from June 1993 to May 1995, on Fora, Prainha, and Boqueirão Beaches. The first two beaches were classified by Dean's morphodynamic index (Ω) as intermediate, and the last as reflective. Slope, beach width and median grain size were significantly different among the beaches. Two-way analysis of variance revealed significant differences in species richness only among the beaches. No significant differences in density of the macrofauna between beaches and season were observed. However, Prainha Beach showed a higher temporal variation of the density of the macrofauna (and higher standard deviation) than the other two beaches. Emerita brasiliensis (Crustacea: Decapoda), Excirolana braziliensis (Crustacea: Isopoda), and Pseudorchestoidea brasiliensis (Crustacea: Amphipoda) were the most abundant species. Canonical correspondence analysis calculated the influence of the temporal variation as 27·5%; the influence of the environmental variation on community structure was 20·9%. The results suggest that in spite of the long-term fluctuations in species density, the beaches did not have temporal differences in the species richness and total density macrofauna during the study period.

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Neves, Frederico Monteiro y Carlos Emílio Bemvenuti. "Spatial distribution of macrobenthic fauna on three sandy beaches from northern Rio Grande do Sul, southern Brazil". Brazilian Journal of Oceanography 54, n.º 2-3 (septiembre de 2006): 135–45. http://dx.doi.org/10.1590/s1679-87592006000200004.

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The spatial distribution of benthic macrofauna on the beaches of Tramandaí, Jardim do Éden and Harmonia, was investigated over five consecutive days in April, 2003. The distribution pattern was also analyzed along with environmental parameters. Three transects were set on each beach, 50 m apart, with four sample stations set along each transect. On every station, three samples of benthic macrofauna were taken daily, with a core sampler with 20 cm diameter. In the midlittoral zone, the polychaete Euzonus furciferus and the isopod Excirolana armata dominated. In the swash zone, tidal migrators, Emerita brasiliensis,Donax hanlevanus and Mesodesma mactroides, were the most abundant species and, on some days, the polychaete Scolelepis gaucha. In the lower zones of the beaches, D. hanleyanus,M. mactroides and the amphipod Puelche orensani dominated. This zonation pattern was found for all three studied beaches, based on the average density of each species, over the five days period. Horizontal variation in the fauna was not found, either inter or intra the studied beaches, possibly due to little variability in slope and homogeneity of sediment grain size presented in the three beaches.

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Kotwicki, Lech, Maria Szymelfenig, Marleen De Troch, Barbara Urban-Malinga y Jan Marcin Węsławski. "Latitudinal biodiversity patterns of meiofauna from sandy littoral beaches". Biodiversity and Conservation 14, n.º 2 (febrero de 2005): 461–74. http://dx.doi.org/10.1007/10531-004-6272-6.

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Alves, Eliana dos Santos y Paulo Ricardo Pezzuto. "Effect of cold fronts on the benthic macrofauna of exposed sandy beaches with contrasting morphodynamics". Brazilian Journal of Oceanography 57, n.º 2 (junio de 2009): 73–94. http://dx.doi.org/10.1590/s1679-87592009000200001.

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The aim of this study was to determine the short-term environmental changes caused by the simultaneous passage of a high energy event on two sandy beaches with different morphodynamic states and their influence on the richness, abundance and distribution of the benthic macrofauna. Two microtidal exposed sandy beaches with contrasting morphodynamics were simultaneously sampled before, during and after the passage of two cold fronts in Santa Catarina. The reflective beach showed a higher susceptibility to the increase in wave energy produced by the passage of cold fronts and was characterized by rapid and intense erosive processes in addition to a capacity for rapid restoration of the beach profile. As regards the dissipative beach, erosive processes operated more slowly and progressively, and it was characterized further by a reduced capacity for the recovery of its sub-aerial profile. Although the intensity of the environmental changes was distinct as between the morphodynamic extremes, changes in the composition, richness and abundance of macrobenthos induced by cold fronts were not evident for either of the beaches studied. On the other hand, alterations in the distribution pattern of the macrofauna were observed on the two beaches and were related to variations in sea level, position of the swash zone and moisture gradient, suggesting that short-term accommodations in the spatial structure of the macrobenthos occur in response to changes in environmental conditions in accordance with the temporal dynamics characteristic of each morphodynamic state.

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Di Camillo, Cristina Gioia Di, Giorgia Luzi, Afghan Danial, Luciano Di Florio, Barbara Calcinai, Sabrina Lo Brutto, Jéssica Luana Santana Mendonça de Oliveira, Agnese Fumanti y Carlo Cerrano. "Characterization of Intertidal Macrofaunal Communities of Two Sandy Beaches under Different Anthropogenic Pressures". Journal of Marine Science and Engineering 10, n.º 12 (12 de diciembre de 2022): 1976. http://dx.doi.org/10.3390/jmse10121976.

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The macrofauna in the intertidal zone of sandy beaches provides the trophic connectivity between land and sea, by linking microbiome, meiofauna, and megafauna, representing a food source for several terrestrial animals, including shorebirds and mammals. However, the macrozoobenthos in urbanised beaches is subjected to intense disturbances, such as breakwater barriers and tourism, which limit or impede the energy transfer from the marine to the terrestrial habitats. Because the information about diversity and abundance of the macrozoobenthos of the intertidal zone on the Mediterranean sandy coasts is scant, the main objective of this study is to increase the knowledge on the macrofauna living in this habitat and to identify taxa sensitive to cumulative human-induced stresses. To achieve this purpose, the structure and dynamics of macrozoobenthic communities from (1) a highly frequented beach characterized by breakwater barriers and (2) a marine protected area (MPA) in the Adriatic Sea were compared. The hypotheses that macrofauna composition and abundance changed in the two sites and over time were tested. Results highlighted that the macrozoobenthos in the MPA is mainly dominated by juvenile bivalves, which peaked from autumn to winter, and to a lesser extent by ostracods and mysids. Conversely, ostracods and the bivalve Lentidium mediterraneum (O. G. Costa, 1830) are particularly abundant in the highly disturbed beach, while the gastropod Tritia neritea (Linnaeus, 1758) increased only during summer. A possible combined effect of breakwater barriers and intense trampling has been theorized to explain the main differences between the two sites especially in the summer.

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T. Frost, Matthew, Martin J. Attrill, Ashley A. Rowden y Andrew Foggo. "Abundance - occupancy relationships in macrofauna on exposed sandy beaches: patterns and mechanisms". Ecography 27, n.º 5 (octubre de 2004): 643–49. http://dx.doi.org/10.1111/j.0906-7590.2004.03860.x.

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Clayton, D. A. "Ghost Crabs of Oman ( Crustacea : Brachyura :Ocypodidae)". Sultan Qaboos University Journal for Science [SQUJS] 1, n.º 1 (1 de enero de 1996): 27. http://dx.doi.org/10.24200/squjs.vol1iss1pp27-35.

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The sandy beaches of the coasts of Oman support five species of Ocypode ghost crabs. Ocypode cordimanus is found on supra-littoral sand dunes while O. saratan O. rotundata, and O. platytarsis occur on the open beaches. O. jousseamei is largely restricted to marine inlets or khawrs. The present records represent range extensions for all five species. The species composition of the Ocypode assemblages of Oman is unique and clearly distinct from that of either East Africa or India. A description of the Species. including at key for their identification is provided.

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Lastra, M., R. de La Huz, A. G. Sánchez-Mata, I. F. Rodil, K. Aerts, S. Beloso y J. López. "Ecology of exposed sandy beaches in northern Spain: Environmental factors controlling macrofauna communities". Journal of Sea Research 55, n.º 2 (febrero de 2006): 128–40. http://dx.doi.org/10.1016/j.seares.2005.09.001.

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Bayed, Abdellatif. "Influence of morphodynamic and hydroclimatic factors on the macrofauna of Moroccan sandy beaches". Estuarine, Coastal and Shelf Science 58 (octubre de 2003): 71–82. http://dx.doi.org/10.1016/s0272-7714(03)00050-7.

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Santos, Marcos Eduardo Miranda y Camila Nascimento Ferreira. "Influência das variáveis ambientais sobre a macrofauna bêntica de praias arenosas". Ciência e Natura 41 (16 de julio de 2019): 5. http://dx.doi.org/10.5902/2179460x34849.

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The beach environment is undoubtedly one of the most dynamic systems that existe. The beaches connect continents and oceans and harbor a wide range of terrestrial and marine species, many of which are used for human consumption and other purposes of great ecological and economic importance. They are formed by several minerals originated from the wear of terrestrial rocks by the action of the waves; wind or river transport; or even produced by living organisms. In addition, they are unstable environments that undergo interference from a wide range of abiotic factors, which in turn have a broad spectrum of variations on short (diurnal) or long (annual) time scales. There is already a wide range of information about the sandy beaches, however, they are scattered confusing students and researchers in this area. Therefore, a brief synthesis of the knowledge already produced about this environment is presented, focusing on the influence of environmental variables on the macrofauna benthic these ecosystems.

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Defeo, Omar y Gastón Martínez. "The habitat harshness hypothesis revisited: life history of the isopod Excirolana braziliensis in sandy beaches with contrasting morphodynamics". Journal of the Marine Biological Association of the United Kingdom 83, n.º 2 (20 de marzo de 2003): 331–40. http://dx.doi.org/10.1017/s0025315403007161h.

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Demographic and life history characteristics of the intertidal isopod Excirolana braziliensis (Isopoda: Cirolanidae) were compared between populations of two exposed sandy beaches with contrasting morphodynamics (reflective vs dissipative) during 22 consecutive months. Most population processes and life history traits did not give support for the ‘habitat harshness hypothesis’ (HHH): abundance of males, females, ovigerous females and juveniles was significantly higher at the reflective beach population, which also presented higher growth rates in size and weight with respect to the dissipative beach population. No significant differences in weight-at-length were found between beaches. Among the compared parameters, only the lower natural mortality rates at the dissipative beach gave support for the HHH. The results were not consistent with a previous analysis of Excirolana braziliensis along Pan-American beaches, which showed that this isopod occurs almost invariably in fine sands of tropical and temperate beaches. The results give strong support to recent findings that show that in macrofauna species capable of sustaining large populations across a wide spectrum of physical conditions, such as Excirolana braziliensis, beach morphodynamics should not be considered the primary factor affecting abundance and life history traits. Instead, our results reinforce the view that sandy beach populations are controlled by the intertwined forces of biotic and abiotic factors operating together.

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Alves, Eliana dos Santos y Paulo Ricardo Pezzuto. "Effect of morphodynamics on annual average zonation pattern of benthic macrofauna of exposed sandy beaches in Santa Catarina, Brazil". Brazilian Journal of Oceanography 57, n.º 3 (septiembre de 2009): 189–203. http://dx.doi.org/10.1590/s1679-87592009000300003.

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This study investigated the effect of environmental factors on the annual average zonation pattern of benthic macrofauna of sub-aerial profile of three exposed sandy beaches of Santa Catarina with different morphodynamic characteristics. Sampling was carried out between March 2000 and March 2001, with monthly frequency on reflective and dissipative morphodynamic extremes and bimonthly frequency on the intermediate state. Results showed that macrobenthic zonation presented marked differences across the morphodynamic spectrum. The main differences observed from reflective to dissipative conditions were: a) increase in the number of species in lower zones of the beach; b) expansion of zones characterized by high water content of sediment and c) increase in the overlapping of zones, mainly on lower levels of the beach. Canonical Correspondence Analysis related these differences to distinctive cross-shore gradients in sediment moisture levels, sediment reworking and mean grain size that exist across the morphodynamic spectrum, showing that it is important to analyze these environmental factors in studies conducted to investigate zonation on microtidal exposed sandy beaches.

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Jiménez-Pérez, L. C. "Effects Of Waste Waters On Benthic Macrofauna Of Sandy Beaches In Todos Santos Bay". Ciencias Marinas 18, n.º 1 (1 de febrero de 1992): 35–54. http://dx.doi.org/10.7773/cm.v18i1.884.

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Bessa, Filipa, Sílvia C. Gonçalves, João N. Franco, José N. André, Pedro P. Cunha y João Carlos Marques. "Temporal changes in macrofauna as response indicator to potential human pressures on sandy beaches". Ecological Indicators 41 (junio de 2014): 49–57. http://dx.doi.org/10.1016/j.ecolind.2014.01.023.

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Sibaja-Cordero, Jeffrey A., Yolanda E. Camacho-García, Juan Carlos Azofeifa-Solano y Bárbara Alvado-Arranz. "Ecological patterns of macrofauna in sandy beaches of Costa Rica: A Pacific-Caribbean comparison". Estuarine, Coastal and Shelf Science 223 (julio de 2019): 94–104. http://dx.doi.org/10.1016/j.ecss.2019.04.032.

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Tarragô, Luana D., Pedro M. A. Ferreira y Laura R. P. Utz. "Benthic Marine Ciliate Assemblages from Southern Brazil and Their Relationship with Seasonality and Urbanization Level". Diversity 12, n.º 1 (31 de diciembre de 2019): 16. http://dx.doi.org/10.3390/d12010016.

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Sandy beaches represent two-thirds of littoral zones worldwide. Complex factors such as winds, waves, and sediment characterize this environment. Ciliophora is one of the most diversified unicellular eukaryotic phyla and, in marine sediments, can reach 40 species per cm³. Despite its importance, knowledge about interstitial communities is still lacking. In the present work, we characterized the assemblage of interstitial ciliates from sandy beaches in the north coastal area of Rio Grande do Sul state, southern Brazil. Fourteen sampling sites distributed along the swash zone of seven beaches with different degrees of urban development were sampled over the course of one year. At each site, eight sediment samples were taken, and a total of 51 species distributed in 37 ciliate genera were identified. Classes Spirotrichea (29%) and Karyorelictea (21%) accounted for 50% of ciliate species richness, with the highest richness being observed within the context of an intermediately urbanized setting. Community analyses revealed that ciliate community is influenced by urbanization degree and season, with distinct assemblages occurring in highly urbanized areas. In beaches affected by a high level of human activity, disturbance effects increased diversity, while in areas showing a milder influence of urbanization, the level of disturbance may be low, resulting in lower richness.

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Pombo, Maíra y Alexander Turra. "Variation in the body growth parameters of the ghost crab Ocypode quadrata from morphodynamically distinct sandy beaches". Brazilian Journal of Oceanography 65, n.º 4 (diciembre de 2017): 656–65. http://dx.doi.org/10.1590/s1679-87592017114606504.

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Abstract Investigations of patterns of distribution of sandy beach macrofauna show that dissipative beaches tend to concentrate higher richness and biomass at the intertidal zone, as well as better fitness and larger sizes of a species, than reflective beaches. For supralittoral crustaceans, these trends are inverted, as predicted by the habitat safety hypothesis (HSH). For ghost-crabs, however, higher population abundance has been observed on dissipative beaches, but their life-history traits and the response to different beach morphologies were not well defined. Here, variation in crab size and growth was evaluated over a one year period using indirect measures from three low-impact beaches on the northern coast of São Paulo State, southeastern Brazil. These beaches represent the three basic types of morphodynamics: dissipative (Costa beach), intermediate (Felix beach) and reflective (Puruba beach). At each site, five 2m wide transects were randomly selected each month, and assessed across the crabs' entire area of occurrence. The fit of the von Bertalanffy body growth model was compared among sites. For all three beaches, a main mode due to the settlement of juveniles (mm) was identified in August and September. In the following summer, according to growth estimates, the settlement group would be approximately the same size as the main mode (mm) that was recorded during the previous summer. Specifically, the growth parameters estimated were: Costa (dissipative) L∞= 46.36mm, K= 0.90year-1 and t0= -0.19; Félix (intermediate) L∞= 57.95mm, K= 0.87year-1 and t0= -0.12; Puruba (reflective) L∞= 53.01mm, K= 1.11year-1 and t0= -0.07. The body growth adjustments were similar between Puruba and Felix, but distinct from Costa. Growth performance indexes ranged from 3.29 (Costa) to 3.46 (Félix) and 3.49 (Puruba), indicating both the homogeneity of this parameter among distinct beaches and close agreement between the intermediate and reflective beaches. This study suggests that variations in the development of ghost crabs concur with those observed for other supralittoral, crustaceans and the habitat safety hypothesis, with higher individual fitness for reflective beaches.

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Santos, Marcos Eduardo Miranda, Cláudia Costa e Silva y Andrea Christina Gomes de Azevedo-Cotrim. "SPATIAL-TEMPORAL DISTRIBUTION OF POLYCHAETA IN URBANIZED SANDY BEACHES OF NORTHEASTERN BRAZIL: TOOLS FOR ENVIRONMENTAL ASSESSMENT". Oecologia australis 25, n.º 04 (15 de diciembre de 2021): 834–45. http://dx.doi.org/10.4257/oeco.2021.2504.04.

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In the last years, the use of Polychaeta as indicators of marine pollution has intensified, due to the sensitivity of these organisms to environmental variations and their significant presence in quantitative and qualitative terms when compared to other benthic fauna organisms. We aimed to analyze the Polychaeta assemblage of two urbanized beaches in São Luís – Maranhão (Brazil), focusing on spatial-temporal distribution and look for the relation of the species sampled and possible contamination to indicate if they are suitable for environmental assessment. Sediment collection was carried out in the intertidal zone of both beaches in dry (September and November/2015) and rainy periods (March and May/2016). The samples were screened for extraction of the species, which were classified at the lowest possible taxonomic level. The samples revealed the following taxa: Lumbrineridae (Scoletoma tetraura), Nereididae (Laeonereis culveri) and Spionidae (Scolelepis sp.). The diversity and abundance of Polychaeta were greater on Caolho Beach. On these beaches, organic enrichment is not the determining variable in the structure of the Polychaeta assembly. Other studies are needed to improve the knowledge on other macrofauna species of the studied areas, comparing the richness among microhabitats and seasons, and thus elaborate conservation strategies for these ecosystems; and to test the hypothesis of the influence of tourism on this assemblage.

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26

Rodil, I. F. y M. Lastra. "Environmental factors affecting benthic macrofauna along a gradient of intermediate sandy beaches in northern Spain". Estuarine, Coastal and Shelf Science 61, n.º 1 (septiembre de 2004): 37–44. http://dx.doi.org/10.1016/j.ecss.2004.03.016.

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27

Silva, Pedro de Sá Rodrigues da, Luciano Peyrer das Neves y Carlos Emílio Bemvenuti. "Temporal variation of sandy beach macrofauna at two sites with distinct environmental conditions on Cassino Beach, extreme southern Brazil". Brazilian Journal of Oceanography 56, n.º 4 (diciembre de 2008): 257–70. http://dx.doi.org/10.1590/s1679-87592008000400001.

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Temporal variations of the macrofauna of sandy beaches have been related to variations in the beach morphodynamics and also to the population dynamics of dominant species. The aim of this article is to describe the temporal variation of the intertidal macrofauna at two sites with distinct environmental condition on Cassino Beach, extreme southern Brazil. At each site three transect lines 50 m apart were defined perpendicular to the shore line, from which samples were collected monthly in triplicate at 4 intertidal levels (10 m apart) from June 2004 to May 2005. During winter a generally low density was observed, due to the absence of recruitments and to the mud deposition, which occurred just before sampling (in April 2004), and to low intensity stranding events. Spring witnessed a population explosion of Scolelepis gaucha, a migration of Mesodesma mactroides adults from the subtidal zone, and a strong stranding event. In the summer, recruitment of M. mactroides, Donax hanleyanus and Emerita brasiliensis was observed. Fall was characterized by low densities, except for D. hanleyanus recruitment. The macrofauna at both sites showed a striking seasonal variation in density and diversity, perhaps attributable to the recruitment of numerically dominant species and physical disturbances (stranding and mud deposition).

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28

Alcaraz, Francisco, Segundo Ríos, María José Delgado y Cristina Inocencio. "SENECIO GLAUCUS L. SUBSP. GLAUCUS, AN EASTERN MEDITERRANEAN TAXON IN THE SANDY SHORES OF SOUTHEASTERN SPAIN". Israel Journal of Plant Sciences 46, n.º 4 (13 de mayo de 1998): 331–35. http://dx.doi.org/10.1080/07929978.1998.10676743.

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Senecio glaucus L. subsp. glaucus, a taxon considered native to the Eastern Mediterranean (Israel and Egypt), has been recognized for the first time in littoral sand beaches and dunes of southeastern Spain. A comparative study between Senecio glaucus subsp. glaucus, Senecio glaucus subsp. coronopifolius, and Senecio gallicus was made with herbarium material from Spain and Eastern Mediterranean countries. A line drawing of the Spanish plant and tables of samples of vegetation to show the ecology of this taxon in southeastern Spain are given.

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29

Abecasis, Carlos Krus. "LITTORAL DRIFT PROBLEMS IN PORTUGAL WITH SPECIAL REFERENCE TO THE BEHAVIOR OF INLETS ON SANDY BEACHES". Coastal Engineering Proceedings 1, n.º 6 (29 de enero de 2011): 23. http://dx.doi.org/10.9753/icce.v6.23.

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After a brief description of the littoral drift regimen in the west and south coasts of Portugal, review is made of the behavior of the works performed in three lagoon inlets located on these coasts and some general principles are inferred which are felt to be valid in the treatment of any similar problems.

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30

BAMBER, ROGER y YOSHIE TAKAHASHI. "Some littoral sea spiders (Arthropoda: Pycnogonida) from Ecuador, with a new species of Anoplodactylus Wilson, 1878 (Phoxichilidiidae)". Zootaxa 815, n.º 1 (14 de enero de 2005): 1. http://dx.doi.org/10.11646/zootaxa.815.1.1.

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Five species of pycnogonid from shallow-water sampling of the hyperbenthos on some sandy beaches in Ecuador in 2001 and 2002 are discussed. Three of the species, Tanystylum isthmiacum Stock, 1955, Anoropallene palpida (Hilton, 1939) and Anoplodactylus californicus Hall, 1912, have been recorded previously from Ecuador waters; one species, Ammothella symbia Child, 1979, is newly recorded for Ecuador; one species of Anoplodactylus is described herein as new. The currently known pycnogonid fauna of Ecuador is listed.

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31

de la Huz, Rosario y Mariano Lastra. "Effects of morphodynamic state on macrofauna community of exposed sandy beaches on Galician coast (NW Spain)". Marine Ecology 29, s1 (julio de 2008): 150–59. http://dx.doi.org/10.1111/j.1439-0485.2008.00230.x.

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32

Scapini, Felicita, Lucia Fanini, Simone Gambineri, Delphine Nourisson y Claudia Rossano. "Monitoring changes in sandy beaches in temperate areas through sandhoppers’ adaptations". Crustaceana 86, n.º 7-8 (2013): 932–54. http://dx.doi.org/10.1163/15685403-00003206.

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Sandhoppers (Amphipoda, Talitridae) are keystone species of sandy beach ecosystems in temperate areas. Several traits have been studied and proposed as bioindicators of impacts on sandy beaches, at individual (physiology and behaviour), population (life cycle, abundance, population dynamics and structure, morphometry and fluctuating asymmetry) and species (genetic structure and variation) levels. Sandy beaches, where these species spend their whole life cycle, are dynamic environments, subject to periodic changes (night-day, tides and seasons), as well as to impacts that may cause erosion or accretion of the littoral zone. The first response of an animal to potentially injuring factors is shown by its avoidance behaviour regarding the potential stress. This behaviour may be a rapid escape reaction, shown by single individuals, the whole or part of the population. Activity rhythms, changes in zonation, burrowing, escape reactions, orientation towards the optimal zone on the beach, are all adaptations to environmental changes, increasing the survival chances of the individuals and populations that express such behaviours. In this paper we present case studies of the talitrid species’ behavioural adaptations related to natural and human impacts on sandy beaches in the Mediterranean: (1) erosion/accretion dynamics of a Tyrrhenian beach in central Italy (Maremma Regional Park), and (2) increasing urbanisation on a beach in north-western Morocco (Oued Laou river mouth). The best behavioural adaptation was shown by the populations from more stable coastlines. For the survival value of rapid and possibly anticipatory responses to stressful factors, behavioural variation may be proposed as an early-warning indicator of environmental changes. The adaptation at higher levels (population and species) may reflect, on the one hand, the evolvability of the species and, on the other hand, the changeability of the environment. Adaptations at population level may be used as bioindicators of past changes over generations and evolutionary times.

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33

Corbisier, Thais Navajas. "Benthic macrofauna of sandy intertidal zone at Santos estuarine system, São Paulo, Brazil". Boletim do Instituto Oceanográfico 39, n.º 1 (1991): 01–13. http://dx.doi.org/10.1590/s0373-55241991000100001.

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Species composition, faunal density, species diversity and zonation patterns of benthic macrofauna, as well as its relation to sediment characteristics were examined and compared in three sandy beaches on the polyhaline area at Santos estuarine system in the State of São Paulo. Samples were collected quarterly during one year (July/1977 - May/1978). Low, mean and high intertidal levels were sampled. Polyehaetes dominated the fauna, both in terms of numbers of species and numbers of individuals. The community structure of Ponta da Praia beach was characterized by high density, low diversity (H') and evenness (J'), due to the dominance of the spionid Scolelepis squamata. At Vicente de Carvalho the fauna was characterized by the dominance of the polyehaetes Laeonereis acuta and Capitella capitata and presented low density, high diversity and evenness. At Bertioga Channel, intermediate values were observed and the fauna was dominated by Scololepis squamata andLaeonereis acuta. The sediment texture was responsible for those figures, although some differences in diversity may be explained by differences in wave energy. The low number of crustaceans and molluscs suggests the effect of the estuarine pollution upon the fauna. The zonation pattern of both species distribution and community structure differed at the studied sites; it was not correlated with sediment characteristics which were relatively uniform down shore; however, the lowest diversity was observed at the high level in all sites.

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34

Gambineri, S., C. Rossano, V. Durier, L. Fanini, C. Rivault y F. Scapini. "Orientation of littoral amphipods in two sandy beaches of Brittany (France) with wide tidal excursions". Chemistry and Ecology 24, sup1 (junio de 2008): 129–44. http://dx.doi.org/10.1080/02757540801966322.

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35

Tessier, Bernadette, Isabelle Billeaud y Patrick Lesueur. "The Bay of Mont-Saint-Michel northeastern littoral: an illustrative case of coastal sedimentary body evolution and stratigraphic organization in a transgressive/highstand context". Bulletin de la Société Géologique de France 177, n.º 2 (1 de marzo de 2006): 71–78. http://dx.doi.org/10.2113/gssgfbull.177.2.71.

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Abstract The aim of the present paper is primarily of pedagogic order. It presents the landscapes of the northeastern littoral of the Bay of Mont-Saint-Michel and explains how these landscapes can be understood in terms of stratigraphic organization and evolution. The northeastern coast of the Bay displays contrasted landscapes and morphodynamic processes along a restricted area. This coast consists in an elongated sandy barrier made of beaches and aeolian dunes, and back barrier tidal flats. A wide estuarine channel-and shoal system migrates in front of the beaches. Because of direct wave attack, the barrier experiences a severe retreat in the north whereas in the south, due to sufficient sediment supply, beaches and dunes tend to prograde. These contrasted processes give rise to different sedimentary bodies and surfaces, the nature, geometry, extension, and time-scale of which are described and discussed through examination of the landscapes. The present-day depositional system can be thus used to illustrate and test sequence stratigraphic concepts such as system tracts, ravinement surfaces and process time-scales.

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36

Barboza, Carlos A. M., Tatiana Cabrini, Gustavo Mattos, Viviane Skinner y Ricardo Cardoso. "Variability of macrofauna distribution along a dissipative log-spiral sandy beach in Rio de Janeiro, Southeastern Brazil". Scientia Marina 81, n.º 1 (27 de marzo de 2017): 111. http://dx.doi.org/10.3989/scimar.04467.03a.

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Log-spiral beaches display defined physical gradients alongshore. However, the majority of studies focus on the variability of a single population of macrofauna species. We aimed to investigate the variation in species distribution and in community structure along ten transects on a log-spiral beach. Principal component analysis indicated a clear physical gradient alongshore. Redundancy analysis showed that the sheltered end was related to smaller particle sizes, higher organic matter content and high densities of polychaetes. The exposed end was characterized by coarser sand, lower organic matter content and a high presence of crustaceans. Model selection indicated that the “best fit” to explain the variability in the number of individuals included grain size and beach slope. Variability of the polychaete Scolelepis squamata was best explained by grain size, slope and sediment sorting. The best model for the cirolanid Excirolana armata only included sediment sorting. The physical gradient in sediment texture and the beach slope explained more than one-third of the variability in community structure. The physical variables were also correlated with the distribution of the individual species. We showed that the physical gradient on log-spiral coasts may be an important driver of macrofauna variability, even at mesoscales and in dissipative conditions.

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37

Covazzi Harriague, Anabella, Cristina Misic, Ilaria Valentini, Eleonora Polidori, Giancarlo Albertelli y Antonio Pusceddu. "Meio- and macrofauna communities in three sandy beaches of the northern Adriatic Sea protected by artificial reefs". Chemistry and Ecology 29, n.º 2 (febrero de 2013): 181–95. http://dx.doi.org/10.1080/02757540.2012.704911.

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38

Bezuidenhout, K., R. Nel, DS Schoeman y L. Hauser. "Historic dispersal barriers determine genetic structure and connectivity in a supratidal sandy-beach brooder". Marine Ecology Progress Series 674 (16 de septiembre de 2021): 1–13. http://dx.doi.org/10.3354/meps13839.

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The supralittoral zones of sandy beaches are particularly vulnerable to coastal development and other activities that cause localised habitat destruction. Supratidal species, such as peracarid crustaceans, which lack a pelagic larval phase and tend to avoid direct contact with the swash, are therefore expected to be distributed as isolated populations, with implications for their long-term survival. Genetic population structure of one such species, the pill bug Tylos capensis, was investigated based on mitochondrial cytochrome c oxidase subunit I (COI) haplotype sequences, to assess demographic history and regional population connectivity in the presence of potential dispersal barriers (an estuary, coastal cliffs) along the Indian Ocean coast of South Africa. Here, pill bugs demonstrated strong and significant genetic structure at the regional scale, with 3 distinct clades across the species’ geographic distribution. At a localised spatial scale, coastal cliffs intersecting the high shore appeared to be a strong barrier to gene flow between adjacent populations, while a permanently open estuary did not limit gene flow. Estimates of historic gene flow and patterns of COI differentiation coincided with greater habitat continuity during the Pleistocene glaciations at sea levels between -75 and -120 m, when the African south coast was probably dominated by sandy beaches. While gene flow among low-dispersing pill bug populations is unlikely to benefit from a network of closely spaced coastal protected areas, the isolated nature of this species, coupled with the cryptic diversity inherent in this taxon, emphasizes the need for their protection. The importance of protecting the intact littoral active zone of beaches is highlighted.

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39

Keppel, Gunnar. "Coastal Vegetation of Taunovo Bay, Pacific Harbour, Viti Levu, Fiji - A Proposed Development Site". South Pacific Journal of Natural and Applied Sciences 20, n.º 1 (2002): 25. http://dx.doi.org/10.1071/sp02006.

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Using four 100 � 10 m transects, the coastal vegetation types and their horizontal stratification at Taunovo Bay, Pacific Harbour, were investigated. The common stratification pattern of herb zone, shrub zone (dominated by the invasive species Chrysobalanus icaco) and tree zone was observed. Littoral forest composed of species commonly associated with sandy beaches and species commonly associated lowland rainforest was observed. This vegetation type is here reported for the first time from Fiji and is probably caused by siliceous deposits from a nearby river. A detailed study of the extend, composition and distribution of this unique vegetation type should be conducted before the development project (planned at the study site) is approved.

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40

Topp, Werner y Richard A. Ring. "Adaptations of Coleoptera to the marine environment. I. Observations on rove beetles (Staphylinidae) from sandy beaches". Canadian Journal of Zoology 66, n.º 11 (1 de noviembre de 1988): 2464–68. http://dx.doi.org/10.1139/z88-365.

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The sandy beaches of British Columbia are inhabited by a small number (11 species) of indigenous Staphylinidae which live near the drift line in the mid to upper littoral zone. They prefer fine-grained sandy beaches and most species feed on other intertidal invertebrates. All species investigated survived submersion in seawater by becoming quiescent, thereby reducing their metabolic rate. Oxygen consumption in seawater was greatly reduced. On re-exposure to air, a large overshoot in oxygen consumption occurred (in Thinopinus pictus), signifying a prior oxygen debt. In Cafius canescens, Cafius seminitens, and Hadrotes crassus the time required to reach full recovery was directly related to the duration of submersion, with 50% mortality in the population when recovery time exceeded 25 min. At a seawater temperature of 10 °C, LT50 was reached at 12–16 h submersion and at 20 °C, after 6.5 h. In Thinopinus pictus, however, recovery time was independent of duration of submersion, although the mortality curves were almost the same as for the three previously mentioned species, with LT50 occurring at 13 h at 10 °C and 7–8.5 h at 20 °C. Bledius monstratus showed symptoms of oxygen depletion only after a considerable time lag. Experimental submersion of this beetle resulted in an LT50 of 18 h at 20 °C.

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41

Dugan, Jenifer E., David M. Hubbard, Michael D. McCrary y Mark O. Pierson. "The response of macrofauna communities and shorebirds to macrophyte wrack subsidies on exposed sandy beaches of southern California". Estuarine, Coastal and Shelf Science 58 (octubre de 2003): 25–40. http://dx.doi.org/10.1016/s0272-7714(03)00045-3.

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42

Boye, Cynthia Borkai, Peter Ekow Baffoe y John Nyamekye Ketibuah. "Assessment of Shoreline Change Along The Sandy Beach of Ellembelle District of Ghana". Geoplanning: Journal of Geomatics and Planning 9, n.º 1 (15 de noviembre de 2022): 17–24. http://dx.doi.org/10.14710/geoplanning.9.1.17-24.

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Sandy beaches are most popular tourists and fish landing sites, and serve as habitat for several endangered species. However, sandy beaches more vulnerable to coastal erosion, particularly those along open oceans. Assessment of shoreline change using reliable dataset aid in understanding the morphology of coastal landforms, the processes associated with their occurrence and support decision making. This paper analysed available multi-temporal spatial dataset and field observations using GNSS techniques to assess the shoreline change along the study area. The shoreline features were extracted from 1974 topographic map and 2005 orthophotographs using the High Water Line (HWL) in conjunction with 2020 spatial data. Shoreline change statistics were computed using DSAS. A geodatabase was created, transects were cast and the shoreline change rates computed using EPR, LRR and WLR methods. Both accretion and erosion were recorded with mean erosion rate of 0.97 m/year. It was observed that sections of the shoreline nourished by Ankobra and Amunzuri rivers were experiencing some accretion, particularly the mouth of the Amuzuri river. The estuary of Amunzuri river was found to be drifting eastwards at a rate of 5.4m/year possibly due to tides, waves and currents. The study concludes that in spite of the littoral drift eastwards, fluvial sediment supplied by coastal rivers accounts for the relative stability of shoreline in the area. Policy formulation regarding possible damming of coastal rivers by government under the ‘one district one dam’ agenda must be carefully considered to avert high levels of erosion along the western coast of Ghana.

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43

Cabrini, Tatiana M. B., Carlos A. M. Barboza, Viviane B. Skinner, Rachel A. Hauser-Davis, Rafael C. Rocha, Tatiana D. Saint'Pierre, Jean L. Valentin y Ricardo S. Cardoso. "Investigating heavy metal bioaccumulation by macrofauna species from different feeding guilds from sandy beaches in Rio de Janeiro, Brazil". Ecotoxicology and Environmental Safety 162 (octubre de 2018): 655–62. http://dx.doi.org/10.1016/j.ecoenv.2018.06.077.

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44

Laurino, Ivan Rodrigo Abrão, Helio Herminio Checon, Guilherme Nascimento Corte y Alexander Turra. "Flooding affects vertical displacement of intertidal macrofauna: A proxy for the potential impacts of environmental changes on sandy beaches". Estuarine, Coastal and Shelf Science 245 (octubre de 2020): 106882. http://dx.doi.org/10.1016/j.ecss.2020.106882.

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45

SCHÖNFELD, JOACHIM y JULIA LÜBBERS. "Checklist, assemblage composition, and biogeographic assessment of Recent benthic foraminifera (Protista, Rhizaria) from São Vincente, Cape Verdes". Zootaxa 4731, n.º 2 (5 de febrero de 2020): 151–92. http://dx.doi.org/10.11646/zootaxa.4731.2.1.

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We describe for the first time subtropical intertidal foraminiferal assemblages from beach sands on São Vincente, Cape Verdes. Sixty-five benthic foraminiferal species were recognised, representing 47 genera, 31 families, and 8 superfamilies. Endemic species were not recognised. The new checklist largely extends an earlier record of nine benthic foraminiferal species from fossil carbonate sands on the island. Bolivina striatula, Rosalina vilardeboana and Millettiana milletti dominated the living (rose Bengal stained) fauna, while Elphidium crispum, Amphistegina gibbosa, Quinqueloculina seminulum, Ammonia tepida, Triloculina rotunda and Glabratella patelliformis dominated the dead assemblages. The living fauna lacks species typical for coarse-grained substrates. Instead, there were species that had a planktonic stage in their life cycle. The living fauna therefore received a substantial contribution of floating species and propagules that may have endured a long transport by surface ocean currents. The dead assemblages largely differed from the living fauna and contained redeposited tests deriving from a rhodolith-mollusc carbonate facies at <20 m water depth. A comparison of the Recent foraminiferal inventory with other areas identified the Caribbean and Mediterranean as the most likely source regions. They have also been constrained as origin points for littoral to subtidal macroorganisms on other Cape Verdean islands. Micro-and macrofaunal evidences assigned the Cape Verde Current and North Equatorial Current as the main trajectories for faunal immigrations. The contribution from the NW African coast was rather low, a pattern that cannot be explained by the currently available information.

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46

Weaver, M. J., J. J. Magnuson y M. K. Clayton. "Distribution of littoral fishes in structurally complex macrophytes". Canadian Journal of Fisheries and Aquatic Sciences 54, n.º 10 (1 de octubre de 1997): 2277–89. http://dx.doi.org/10.1139/f97-130.

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By considering patchiness in the littoral vegetation, we were able to distinguish within-lake distributions among species and between young-of-the-year and yearling-and-older fishes. We characterized the macrophytes in Lake Mendota, Wisconsin, along transects using rake grabs to estimate species diversity and sonar charts to estimate the patchiness at 1-m intervals. We discerned two distinct littoral fish assemblages, one characterized by rock bass (Ambloplites rupestris) and smallmouth bass (Micropterus dolomieu) in unvegetated areas and another by a diverse assemblage in vegetated areas. Patchiness of macrophytes, not simply abundance, determined variations in the specific structure of the fish assemblage: e.g., yellow perch (Perca flavescens) were more dominant and abundant where vegetation was species rich and structurally complex as well as abundant. Young-of-the-year and yearling-and-older fishes differed in their distribution patterns: e.g., age 0 bluegill (Lepomis macrochirus) were more abundant where Eurasian watermilfoil was abundant and patchy and yearling-and-older bluegill where vegetation was more dense and species rich. Furthermore, yearling-and-older black bullhead (Ameiurus melas) and brown bullhead (Ameiurus nebulosus) were more common in patchy macrophyte beds than in species-rich vegetation. The largest catches of age 0 white bass (Morone chrysops) occurred at sites with sandy shallow beaches and patchy milfoil beds farther offshore. These patterns were discerned because we assessed macrophyte structural complexity at multiple scales and we separated young-of-the-year from older fishes.

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47

NADERLOO, REZA y MICHAEL TÜRKAY. "Decapod crustaceans of the littoral and shallow sublittoral Iranian coast of the Persian Gulf: Faunistics, Biodiversity and Zoogeography". Zootaxa 3374, n.º 1 (4 de julio de 2012): 1. http://dx.doi.org/10.11646/zootaxa.3374.1.1.

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A total of 150 species belonging to five infraorders (Caridea, Stenopodidea, Thalassinidea, Anomura and Brachyura) are recorded from the Iranian coast of the Persian Gulf. About 17% (26 species) are new records for the area. The infraorder Brachyura shows the highest species richness with 83 species. The Anomura and Caridea, with 29 and 27 species, respectively, follow. The Thalassinidea is represented by 10 species, whereas Stenopodidea only by one. The species with the highest occurence are ranked as follows: Nanosesarma sarii Naderloo & Türkay, 2009 (Brachyura), Alpheus lobidens De Haan, 1850 (Caridea), Metopograpsus messor (Forskål, 1775) (Brachyura), Coenobita scaevola (Forskål, 1775) (Anomura), Diogenes avarus Heller, 1865 (Anomura), Pilumnopeus convexus Maccagno, 1936 (Brachyura) and Portunus segnis (Forskål, 1775) (Brachyura). Among the surveyed habitats, mixed rocky/cobble show the highest diversity with 99 (66%) recorded species, followed by sedimentary muddy-sandy substrates and mangroves with 40 (26%) and 24 species (16%), respectively. The least diverse habitat is sandy beaches with 6 species. The decapod fauna shows a predominance of wide ranging Indo-West Pacific species (43%) and a small degree of endemism (5%). A considerable number of species is restricted to the northwestern Indian Ocean (27%), supporting the presence of a zoogeographical subregion within the western Indian Ocean Province.

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48

Santos, T. M. T. y D. Aviz. "Macrobenthic fauna associated with Diopatra cuprea (Onuphidae: Polychaeta) tubes on a macrotidal sandy beach of the Brazilian Amazon Coast". Journal of the Marine Biological Association of the United Kingdom 99, n.º 4 (25 de septiembre de 2018): 751–59. http://dx.doi.org/10.1017/s0025315418000711.

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AbstractTube-building polychaetes are an important group of marine bioengineers in soft-bottom habitats, where they provide structures that potentially influence the composition of the benthic community. The present study investigated the effects of Diopatra cuprea tubes on the structure of the macrobenthic fauna found on a sandy beach of the Amazon coast. Samples were collected in June (rainy season) and September (dry season) 2012 in two different areas: (1) an area in which D. cuprea tubes were present, and (2) a control area, in which worm tubes were absent. A total of 53 taxa were found, of which 30 were associated exclusively with D. cuprea tubes. While large aggregations of D. cuprea were not found in the study area, the presence of even a single tube may have a significant influence on the environmental conditions available for other organisms, especially those adapted to consolidated or muddy substrates. The two areas presented different seasonal patterns. A significant increase in the abundance and richness of the macrofauna was observed in area 1 in the rainy season, when the density of worm tubes increased and the hydrodynamic conditions were less intense. The results of the study highlight the importance of this organism as an ecosystem engineer on the sandy beaches of the Amazon coast.

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49

Peterson, Curt D. y Maureen Walczak. "Recent Transport and Deposition of Littoral Sand Across the Inner-Shelf of Central Oregon: Further Constraints on Estimating Depths of Closure (30–34 m) during Future Sea Level Rise in the Pacific Northwest Region, USA". Journal of Geography and Geology 14, n.º 2 (7 de junio de 2022): 1. http://dx.doi.org/10.5539/jgg.v14n2p1.

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In this article, geologically recent sedimentation rates across a high wave- and wind-energy inner-shelf are used to constrain depths of closure, which are needed to estimate potential offshore displacements of littoral (beach) sand that could result from future sea level rise (SLR). Seven shallow vibracores (1.0–2.3 m subsurface depth) were analyzed from a single transect across the inner-shelf (19–72 m water depth) at the South PacWave study site in the high-wave energy (peak wave Hs= 10–15 m) coast of Central Oregon. The vibracores were 14C dated to establish 1) near-modern mixing depths and 2) net sedimentation rates that equaled or exceeded rates of coeval SLR (10 cm century-1) during very latest-Holocene time (≤1.0 ka). Sedimentation rates of 17 cm century-1 and 31 cm century-1 for vibracore P1-2A22 in 34 m water depth do exceed coeval SLR, even after accounting for apparent mixing depths of 60–100 cm. But sedimentation rates in deeper core sites (47–53 m water depth) do not approach coeval SLR rates. These results support a proposed near future (one century) 30 m depth of closure in the innermost-shelf of northern Oregon. Vibracore sand grain sizes (mean 0.20±0.03 mm 1σ, n=18) are similar across the inner-shelf, but heavy-mineral sand tracers confirmed that the latest-Holocene inner-shelf sand accumulations were supplied from seaward transport of littoral sand. The net loss of littoral sand to the inner-shelf sand sink accounts for the narrowing and thinning of beach deposits in northern Oregon during latest-Holocene time. A 1.0 m thickness of littoral sand displaced across the innermost-shelf (5–30 m water depth) following a 1.0 m SLR, or equivalent increase in offshore accommodation space, would yield a cross-sectional area of 1.5x103 m2. That value is three times larger than the mean cross-sectional area of the modern adjacent beaches (mean 4.8x102 m2) in the South PacWave study area. Following a possible near future SLR of 1.0 m, the popular sandy beaches of northern Oregon could be converted to intertidal gravel/algae covered bedrock platforms.

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Stoica, Elena, Magda Nenciu, Silvia Mădălina Creangă, Mihaela Cosmina Tănase, Dragoș Marin, Andreea Mădălina Ciucă y Vasile Pătrașcu. "Assesment of the Marine Litter on the Romanian Black Sea Beaches". Cercetări Marine - Recherches Marines 51, n.º 1 (12 de enero de 2021): 49–63. http://dx.doi.org/10.55268/cm.2021.51.49.

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"The paper presents the results of seasonal marine litter surveys carried out during the period 2018 – 2019 along the Romanian littoral of the Black Sea on 3 sandy beaches differing in their touristic exploitation and urbanisation. The assessment of abundance and composition of macrolitter (> 2.5 cm) and microplastics (1-5 mm) followed the monitoring methodology described in the EU MSFD TG10 guidance (Galgani et al., 2013). Out of the fifty-five litter types mostly monitored, cigarettes buts and plastic/polystyrene pieces (2.5 cm - 50 cm) made up the highest contribution with more than 50% in all years. The mean abundance of total microplastics ranged from 4 and 272 particles/m2 among sites; the microplastics were mostly expanded polystyrene (EPS), fragments and films. The microplastic abundance in touristic beaches of Mamaia resort (Marina Regia and Malibu) was between 2 and 30 times higher than in protected wild areas (Vadu). Overall, the different types and quantities of marine litter found during our study were related to differences in human activities set up in all three locations in touristic and post-touristic season 2018 and 2019. The highest macrolitter and microplastic concentrations were recorded in the southern area of Mamaia summer resort (Malibu beach) indicating that beside the level of coastal infrastructure development, the seasonal tourists and local population density are important factors affecting marine litter pollution level on the Romanian beaches. Key-Words: marine litter, macrolitter, microplastics, beach sediment, Black Sea "

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