Artículos de revistas: "Littoral macrofauna"

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Vaghela, A., P. Bhadja, J. Ramoliya, N. Patel y R. Kundu. "Seasonal variations in the water quality, diversity and population ecology of intertidal macrofauna at an industrially influenced coast". Water Science and Technology 61, n.º 6 (1 de marzo de 2010): 1505–14. http://dx.doi.org/10.2166/wst.2010.503.

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Present communication reports the physico-chemical and biological quality of seawater and status of benthos of a highly industrialized shore of the north-western coastline of India. The coastal area considered for the present study, encircled by a variety of industries, was divided into two sampling sites and monitored for two consecutive years. Results of the water quality suggest that the obtained values of the physical and chemical parameters of seawater were comparable with data reported earlier. However, data obtained in the biological parameters of the seawater showed a declining trend. Results of the intertidal macrofaunal diversity studies revealed that the muddy upper littoral zones were represented by few species of coelenterata, porifera, arthropoda and mollusca. In the rocky—muddy middle littoral zones, gastropods, stars fishes, corallites, crabs, polychetes and tubeworms were present, whereas, predominantly rocky lower littoral zones were comparatively rich in macrofaunal diversity with small patches of coral colonies. However, when the results obtained in the present study was compared with that of earlier reported data, it was clear that the macrofaunal diversity indeed declined considerably over the years. This may be due to habitat destruction and habitat alteration in the coastline caused by increased anthropogenic activities in the area. Seasonal variations in the population density and abundance were observed in most of the faunal groups except in sessile corals and sponges. This may be due to local migration of the faunal groups towards deeper regions of the Gulf, as supported by the analysis of similarity, to avoid influx of freshwater during monsoon, and high temperature during summer and post monsoon seasons. The overall assessment of different parameters of this study revealed that though the physico- chemical characteristics of the seawater did not varied much from the earlier reported status, the biological characteristics of the seawater and intertidal zone was affected possibly by a high degree of anthropogenic pressure.

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Hampton, Stephanie E. y Ian C. Duggan. "Diel habitat shifts of macrofauna in a fishless pond". Marine and Freshwater Research 54, n.º 7 (2003): 797. http://dx.doi.org/10.1071/mf02165.

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Most studies of pond animals are undertaken during the daytime, despite evidence that many pond organisms demonstrate marked nocturnal changes in behaviour. Nocturnal studies of animals in fishless ponds are particularly rare, probably because diel changes in aquatic animal behaviour are often found to be a response to visual predation by fish. We used non-metric multidimensional scaling (MDS) and analysis of similarity (ANOSIM) to detect patterns of similarity in the community composition of macroinvertebrates and amphibians in samples taken from vegetated and unvegetated areas during the day and night in a fishless Vermont pond. We tested the hypotheses that (i) macrofaunal activity increased at night near the pond surface, and (ii) horizontal movement of the pond community was occurring on a diel cycle. At night, many taxa were more abundant in the surface waters and the community showed a general habitat expansion or shift from the littoral zone towards the edge and central waters. Our results challenge the assumptions that one would make about pond animal habitat use and interactions based solely on daytime studies. Even in fishless systems, where diel changes are unexpected, habitat use and behaviour might change at night and affect the strength and variety of species interactions.

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CALLISTO, M., F. A. R. BARBOSA y P. MORENO. "The influence of Eucalyptus plantations on the macrofauna associated with Salvinia auriculata in Southeast Brazil". Brazilian Journal of Biology 62, n.º 1 (febrero de 2002): 63–68. http://dx.doi.org/10.1590/s1519-69842002000100008.

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The influence of Eucalyptus plantations on the structure and composition of macroinvertebrate communities associated with the aquatic fern Salvinia auriculata Aublet were investigated in a high altitude lake bordered by either secondary Atlantic forest or Eucalyptus plantations. Comparisons of the diversity of Chironomidae (Diptera, Insecta) larvae in the littoral zone between these two vegetation types showed higher diversity of larvae in waters bordered by Eucalyptus. The results demonstrated that the predominance of carnivorous taxa among the macroinvertebrate fauna appears to be the major controlling factor for limiting diversity in lake areas bordered by Eucalyptus.

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Berezina, N. A. "Spatial distribution of macrofauna in a littoral zone with drifting macroalgae in the Neva estuary". Estonian Journal of Ecology 57, n.º 3 (2008): 198. http://dx.doi.org/10.3176/eco.2008.3.03.

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Farrapeira, Cristiane Maria Rocha, Arthur Vinícius de Oliveira Marrocos de Melo, Débora Ferreira Barbosa y Karla Maria Euzebio da Silva. "Ship hull fouling in the port of Recife, Pernambuco". Brazilian Journal of Oceanography 55, n.º 3 (septiembre de 2007): 207–21. http://dx.doi.org/10.1590/s1679-87592007000300005.

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Ports of big coastal cities are exposed to exotic species as a consequence of shipping traffic. As the Port of Recife receives an annual average of 491 ships from other regions of Brazil and from all over the world, this work was aimed at knowing which marine animals were passively transported on such vessels hulls, in order to map and monitor new bioinvasions in the area. Thus, 32 vessels of several origins were investigated between November 2005 and March 2006, samples were taken and the macrofauna identified. Sixty species of associated animals were identified, consisting of 28 sessile species, particularly the Cirripedia Balanomorpha and Lepadomorpha as dominants, 8 sedentary animals, namely Mytillidae and Dreissenidae and 23 free-living species, particularly, Caprellidae, Gammaridae, Tanaidacea, Turbellaria, Nemertea and Polychaeta. The first occurrence of Conchoderma virgatum was recorded with exact location for the Brazilian littoral, and Conchoderma auritum, Amphibalanus subalbidus and Haliplanella lineata were recorded for the first time at the littoral of Pernambuco State. The invasion pathway was confirmed for Amphibalanus reticulatus and Mytilopsis leucophaeta, invader species of the estuarine area of Recife's city. Megabalanus coccopoma was considered as a risk invader species for the region.

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Barnes, David K. A. "Marine colonization and biodiversity at Ascension Island and remote islands". Journal of the Marine Biological Association of the United Kingdom 97, n.º 4 (28 de septiembre de 2015): 771–82. http://dx.doi.org/10.1017/s0025315415001526.

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Little is known about colonization of remote island coasts by marine invertebrates, other than corals. The structure of hard substrata assemblages was investigated across Ascension Island's littoral zone in comparison with other sites. Arrays of acrylic panels were deployed at two sites for 2 years at Ascension Island to measure subtidal recruitment. Colonization of panels at Ascension I. was low, though space occupation, abundance and richness varied considerably. After ~1 and 2 years Ascension panels were <17 and <37% covered by fauna and each had <22 recruits and 54 recruits (per 100 cm2) respectively, amongst the lowest density of recruits reported. Recruitment rates of corals (25 m2 year−1) at Ascension I. were also similar to the lowest levels reported elsewhere (e.g. at Bermuda or Midway islands). Less dispersive animal types, e.g. cheilostome bryozoans, were poorly represented. Panels immersed in Tanzania and Scotland were >30% covered, with >76 recruits per 100 cm2 and with bryozoans well represented after 1 year. Across-littoral surveys of established macrofauna at five remote islands (Ascension I., Easter I., Azores, South Georgia and Signy I., Antarctica) revealed similar trends of a rich sublittoral and lower littoral reducing drastically up-shore; molluscs dominating abundance and species numbers, whilst polychaetes, crustaceans and echinoderms were well represented. Established sessile animals occurred patchily at a mean density of 8.26 m−2 but recruits had mortality levels >99%. Polar or remote temperate/tropical sites are typically less colonized than at non-remote, low latitudes but the lowest levels reported are at remote polar sites. Reduced colonization at Ascension island reflects remoteness.

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Thorp, James H. "Linkage between Islands and Benthos in the Ohio River, with Implications for Riverine Management". Canadian Journal of Fisheries and Aquatic Sciences 49, n.º 9 (1 de septiembre de 1992): 1873–82. http://dx.doi.org/10.1139/f92-207.

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Anthropogenic reductions in braiding, meandering, and snag abundance have diminished habitat heterogeneity of regulated rivers, factors directly influencing island formation, retentive capacity of the ecosystem, and community diversity. Habitat heterogeneity associated with riverine islands should, therefore, be of paramount importance to the ecosystem and may require special management protection. To understand the influence of these alluvial formations on riverine benthos, macroinvertebrate assemblages were sampled near three islands in the Ohio River above Louisville, Kentucky, USA. Benthos was collected along six bank-to-bank transects located 1 km above and below islands and near the head, middle, and foot of islands. Islands have significant positive effects on invertebrate density and diversity that appear related to changes in physical habitat characteristics. Current velocity and substrate particle size are diminished in narrow channels between islands and shore, and areal extent of the littoral zone is enhanced within an otherwise deepwater region. Shallow water and slower currents promote growth of submerged vascular plants and macrophytic algae. Because of a relatively low exploitation by humans, islands probably enhance snag formation and input of organic matter, both factors having positive effects on macrofauna. Creation of selected riverine preserves near islands as a management tactic is recommended.

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Bernem, Karl-Heinz van, Agmar Müller y Jürgen Dörjes. "ENVIRONMENTAL OIL SENSITIVITY OF THE GERMAN NORTH SEA COAST". International Oil Spill Conference Proceedings 1989, n.º 1 (1 de febrero de 1989): 239–45. http://dx.doi.org/10.7901/2169-3358-1989-1-239.

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ABSTRACT A contiguous region of tidal flats about 448 km (280 miles) long and up to 21 km (13 miles) wide extends along the North Sea coasts of the Federal Republic of Germany, The Netherlands, and Denmark. This region is called the Wadden Sea. It is of enormous value as a cleansing site for the North Sea water, as a nursery for young fishes, and as a feeding grounds for nearly all Palearctic species of wading birds and waterfowl. The proximity of important shipping routes and ports is a permanent threat, especially to the German part of the region, which became a national park in 1986. The results of several field surveys, conducted from 1976 through 1986, revealed the necessity of an ecologically based sensitivity map for oil spill contingency planning. To evaluate properly the great variety of possible conditions resulting from the interrelationships of biotic and abiotic parameters, a system was developed to encompass such features, including the persistence of oil in the sediment, and the vulnerability and regenerative capability of a large proportion of the biota. Species of halophytes, mammals, fishes, birds, macrofauna, meiofauna, and microphytobenthos were evaluated to determine their physiological and ecological sensitivities to oil contamination. The evaluation was made considering autecological and synecological parameters. To test the applicability of the technique, a map was made of the littoral zone between the Weser and Elbe Rivers. The results were accepted by the West German organization for the control of oil spills at sea (ÖSK). Mapping will be continued under the direction of the Geesthacht Research Center until 1992. Eventually the project will cover the entire German part of the Wadden Sea through the financial support of the GKSS, the Umweltbundesamt (UBA), the ÖSK, and the national park authorities. A data processing system is being established by the GKSS so that the results can be used not only for oil spill control but also for the analysis of the ecosystem and to help the national park bureaus fulfill their obligations.

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Mariani, Simone, Susana Pinedo, Marc Terradas, Maria Elena Cefalì, Eglantine Chappuis y Enric Ballesteros. "Habitat structure and zonation patterns of northwestern Mediterranean shoreline strands". Scientia Marina 81, n.º 2 (14 de junio de 2017): 269. http://dx.doi.org/10.3989/scimar.04445.09a.

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We studied the habitat structure (macrofaunal assemblages and bottom types) and zonation patterns of 29 unvegetated shoreline strands along the 900-km coast of Catalonia (NW Mediterranean Sea). Organisms were sampled with grabs, pitfall traps, sticky traps, clam nets and spades to ensure capture of the different proportions of macrofaunal assemblages from the supra-, medio- and infralittoral levels. We collected 211 taxa: 194 animals and 17 algae. The most abundant and dominant organisms collected with van Veen grabs were Nematoda, Oligochaeta and Collembola at the supralittoral level; the polychaetes Saccocirrus spp. and Pisione remota, the amphipod Corophium orientale, Nematoda, and Turbellaria at the mediolittoral level; and Nematoda at the upper infralittoral level. SIMPER analysis revealed great dissimilarity between the organisms inhabiting the supralittoral and the other littoral levels. Regarding the epifauna, the sticky traps used at the supralittoral level mainly collected Collembola, which were nearly absent in pitfall traps. The qualitative study performed with a clam net and a small spade revealed that Nematoda, Saccocirrus spp., Turbellaria, Nemertea and the polychaete P. remota were the most abundant animals at both the medio- and the infralittoral levels and no differences were found between these levels. Different qualitative sampling methodologies showed that in fine sediments the bivalves Donax trunculus and D. semistriatus determined more than 97% of dissimilarity from coarse-sand sites. Richness increased in protected sandy and cobble shores. Littoral level and bottom-type features were only to a certain extent valid indicators of specific biotic components for a specific habitat.

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10

Armonies, Werner y Monika Hellwig-Armonies. "Synoptic patterns of meiofaunal and macrofaunal abundances and specific composition in littoral sediments". Helgoländer Meeresuntersuchungen 41, n.º 1 (marzo de 1987): 83–111. http://dx.doi.org/10.1007/bf02365101.

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11

Malm, Torleif, Sonja Råberg, Sabine Fell y Per Carlsson. "Effects of beach cast cleaning on beach quality, microbial food web, and littoral macrofaunal biodiversity". Estuarine, Coastal and Shelf Science 60, n.º 2 (junio de 2004): 339–47. http://dx.doi.org/10.1016/j.ecss.2004.01.008.

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12

Henninger, T. O. y P. W. Froneman. "Macrofaunal Community Structure in the Littoral Zone of a Freshwater-Deprived, Permanently Open Eastern Cape Estuary". African Zoology 46, n.º 2 (octubre de 2011): 263–79. http://dx.doi.org/10.3377/004.046.0206.

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13

Henninger, T. O. y P. W. Froneman. "Macrofaunal community structure in the littoral zone of a freshwater-deprived, permanently open Eastern Cape estuary". African Zoology 46, n.º 2 (octubre de 2011): 263–79. http://dx.doi.org/10.1080/15627020.2011.11407500.

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14

Massé, Henri L. "Les carbonates associés à la macrofaune des sables fins littoraux en Méditerranée nord-occidentale". Oceanologica Acta 22, n.º 4 (julio de 1999): 413–20. http://dx.doi.org/10.1016/s0399-1784(00)88724-1.

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15

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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Diedrich, Cajus. "Palaeoecology, facies and stratigraphy of shallow marine macrofauna from the Upper Oligocene (Palaeogene) of the southern Pre-North Sea Basin of Astrup (NW Germany)". Open Geosciences 4, n.º 1 (1 de enero de 2012). http://dx.doi.org/10.2478/s13533-011-0051-1.

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AbstractThe 22 meter thick marine carbonate Upper Oligocene series of Astrup (NW Germany) is correlated with the Chattian type section of Doberg. It indicates a more constrained palaeogeographical and biostratigraphical position ranging from the biozones of Chlamys (C.) decussata (upper Chattian A) to Chlamys (C.) semistriatus (lower Chattian C). The macrofauna can be subdivided into three main benthic communities: A. the „coarse gravel spondylid beach fauna“ of the shore zone with „pebble beach facies“ dominated by sessile brachiopods, large balanids, spondylids, oysters or small regular echinoids. Borings are common in pebbles; B. the „glauconite fine gravel brachiopod-bryozoan littoral fauna“ of the shallow subtidal zone where a terebratulid/lithothamnid dominated fauna/flora is present. The rhodophyceans were most possibly anker stones and substrates for cirripeds and serpulids; C. the „glauconite carbonate sand phytal fauna“ of the shallow subtidal zone with a rich benthic mollusc dominated fauna. Indirect evidence for seagrass and macroalgae occurs on the attachment negatives of balanids and oysters, and also on Cibicides foraminifera or bryozoans like Cellepora. The facies types along the Wiehengebirge Island and Teutoburger Wald Peninsula coasts of the southern Pre-North Sea Basin differ with respect to their benthic communities to that of the siliciclastic Leipziger and the Rhenish Bay facies.

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17

"Oil pollution studies of the Solbergstrand mesocosms". Philosophical Transactions of the Royal Society of London. B, Biological Sciences 316, n.º 1181 (16 de septiembre de 1987): 641–54. http://dx.doi.org/10.1098/rstb.1987.0043.

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Two medium-scale ecosystems (mesocosms) were built on the Oslofjord: one a hard-bottom intertidal system and the other a subtidal soft-sediment system. The hard-bottom mesocosm consists of four basins, two controls and two which were dosed with diesel-oil (129 μg 1 -1 a high oil (HO) dose and 29 μg 1 -1 a low oil (LO) dose). Both oil doses caused high mortality of Mytilus edulis and growth was reduced in the macroalgae Ascophyllum nodosum and Laminaria digitata . Recruitment of Littorina littorea was also affected by oil so that populations declined over time. Subtidal benthic communities have been established in the mesocosm and show variations in sediment chemistry within the range found in the field. Although recruitment of benthic macrofauna is reduced, dominant species and species structure remain closely similar to that in the field over six months. Bioturbation effects studied in the mesocosm have shown the important influence of large, rare species in structuring benthic communities, a finding which would not be possible in nature by diving or by the use ofsubmersibles. Preliminary results from a community taken from 200 m depth and established in the mesocosm suggest that it is now possible to do detailed manipulation experiments on communities simulating the whole continental shelf.

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Artículos de revistas sobre el tema "Littoral macrofauna"

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