139 research outputs found

    Especies de priapúlido, foronídeos y pogonóforos de la Península Ibérica y mares adyacentes

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    A contribution to the knowledge of the phylum Sipuncula in the Maltese Islands (Central Mediterranean)

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    Specimens of the phylum Sipuncula collected through a span of eleven years from around the Maltese Islands have revealed the existence of fifteen species and subspecies. The majority of these animals are new records for the Maltese Islands.peer-reviewe

    Sipuncula de la región magallánica comparada con zonas adyacentes de la Antártida

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    The Magellan sipunculan fauna includes 4 families, 7 genera and 16 species. A comparison between this fauna and that from adjacent regions of Antarctica has been made. A total of 8 species and 3 genera are shared by the compared areas. Univariate analyses show no significant statistical differences among the investigated faunas, whereas a multivariate analysis corroborates that the effects of the Antarctic Convergence are stronger at the level of genera than species. Only 3 genera were able to cross over this zoogeographical boundary. However, these 3 genera succeeded in the new biotopes of Antarctica, since a total of 16 species have been recorded, compared with the 8 species only found in the Magellan region.La fauna magallánica de sipuncúlidos presenta 4 familias, 7 géneros y 16 especies. Se lleva a cabo una comparación entre esta fauna y la procedente de zonas adyacentes de la Antártida. Un total de 8 especies y 3 géneros están presentes en ambas zonas. Los resultados del análisis univariante indican la ausencia de diferencias estadísticas significativas entre las faunas investigadas, mientras que el análisis multivariante revela que los efectos de la Convergencia Antártica son más importantes a nivel de género que de especie. Sin embargo, estos géneros tuvieron cierto éxito en la colonización progresiva de los nuevos biotopos antárticos, dado que se han encontrado un total de 16 especies frente a las 8 exclusivas del área magallánica

    Biomass size-spectra of macrobenthic assemblages along water depth in Antarctica

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    Several biomass size spectra of benthic assemblages were constructed along a water depth gradient on the southern coast of Livingston Island (South Shetland Islands, Antarctica). The size-spectrum for shallow bottoms (200 m) zones showed unimodal spectra with biomass peaks in the 1-2 and 0.5-1 g weight ranges respectively. Filter-feeders also affected the larger size classes at intermediate depths, whereas they were almost absent in deeper waters. The slope of the normalized size-spectrum at shallower bottoms (-0.76) was different from those of intermediate (-1.25) and deeper (-1.31) zones. This clearly indicated 2 contrasting faunal strategies: a biomass increase with size in shallow waters, whereas the biomass decreased with size in deep waters. Estimates of total secondary production were calculated using allometric equations published in the literature. Results indicated a decrease of total secondary production along water depth, with 15 g C m-2 yr-1 in shallow waters, 9 g C m-2 yr-1 at intermediate bottoms and 8 g C m-2 yr-1 at deep bottoms. The pattern of the biomass size spectrum for shallower waters suggested that there was a predictable and regular supply of food, which allowed accumulation of biomass in the larger size classes corresponding to filter-feeder organisms. Conversely, the concentration of biomass in smaller size classes of the spectra for intermediate and deeper waters pointed to more unpredictable and fluctuating food conditions arriving from the overlying layer to the deeper sea floor. Sufficient evidence exists in the literature to indicate that a tight pelagic-benthic coupling was causing biological enhancement of a suspension-feeding macrofauna at shallow bottoms, and that below 100 m depth the effects of the coupling were rather weak.Versión del editor2,483

    Will improving wastewater treatment impact shorebirds? Effects of sewage discharges on estuarine invertebrates and birds

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    Human communities often discharge wastewaters into estuaries, influencing their organic and pollutant loading, benthic community and trophic structure. The implementation of the Water Framework Directive has encouraged the treatment of wastewater discharges across European estuaries, but the implications for invertebrate and waterbird communities are poorly understood. We explore the effects of untreated sewage discharges on the distribution and abundance of foraging black-tailed godwits Limosa limosa and their main benthic prey (bivalves and polychaetes) on the Tejo estuary in Portugal, a major European Special Protection Area with ongoing wastewater improvements. Patches of mudflat in close proximity to sewage streams (70 m), and godwits foraging in these areas can attain the highest intake rates recorded for the estuary. However, high intake rates can also be attained on bivalve prey, and bivalve biomass and density increase slightly with distance from sewage streams. As the organic input from sewage outfalls influences invertebrate abundance and godwit foraging rates over relatively small areas, the ongoing implementation of a sewage treatment network on the Tejo estuary seems likely to have only a limited impact on the wintering godwit population. The localized effect of untreated sewage discharges on benthic communities suggests that the implications for predatory birds are relatively minor where alternative prey are available, but may be more severe in locations with more depauperate, polychaete-dominated invertebrate communities

    Macrozoobenthic changes on rocky shores of the Bight of Bilbao: 14 years of monitoring biological recovery

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    Benthic communities on rocky shores from the Bight of Bilbao, known as the Abra de Bilbao (northern Spain) and the adjacent coast have been studied during 14 years (1984-1998) within the framework of an environmental monitoring programme for both subtidal and intertidal zones. The study area is now experiencing a process of generalised environmental improvement in its water quality, as a result of the region's industrial recession and the implementation of a comprehensive renovation sewage system, which is still in progress. Biological recovery has been analysed with uni- and multivariate techniques, which make it possible to differentiate several recovery stages, grouped according to the littoral zone sampled. A total of 12 taxa have been selected as characteristics of different environmental situations in space and time, the most sensitive of which are Sagartiidae, Mytilidae, Patellidae and Chthamalidae. The need to use alternative analyses in long term studies of hard bot- tom macrozoobenthos is highlighted. A three-phase conceptual model based on own results and previous works is proposed, which describes the current situation, as well as the recorded or expected changes. The model comprises two parts: a) one for the subtidal and lower intertidal levels, where biotic strategies related to the inverse patterns of fauna and flora dominance are emphasised; b) another for the upper intertidal level, where the appearance and development of a barnacle belt play a crucial role. The model is intended to serve as an environmental tool able to detect changes in the recovery process of the Bight of Bilbao and similar bays elsewhere.Se han estudiado las comunidades bénticas de sustrato rocoso del abra de Bilbao y su costa adyacente durante 14 años (1984-1998), dentro de un programa de seguimiento biológico de los medios submareal e intermareal. El área de estudio se encuentra en un proceso de mejora de la calidad ambiental de sus aguas como consecuencia de la recesión industrial y del Plan Integral de Saneamiento, actualmente en desarrollo. Se ha constatado la recuperación biológica por medio de técnicas univariantes y multivariantes, proponiéndose una serie de etapas en dicha recuperación, diferentes según el nivel litoral. Se ha seleccionado un total de doce taxones como los máximos responsables de discriminar situaciones en el espacio y en el tiempo, entre los que destacan por su mayor sensibilidad: Sagartiidae, Mytilidae, Patellidae y Chthamalidae. Se demuestra, asimismo, la necesidad de utilizar diferentes tipos de análisis en los estudios a largo plazo del macrozoobentos de sustrato rocoso. Con base en estos resultados y en trabajos previos, se articula un modelo conceptual en tres fases, describiendo la situación actual del bentos y los cambios registrados o previsibles. El modelo consta de dos partes: a) el correspondiente a los niveles submareal e intermareal inferior, donde se enfatizan las estrategias relacionadas con los patrones inversos de dominancia de la fauna y la flora; b) el concerniente al nivel intermareal superior, donde desempeñan un papel fundamental la aparición y el desarrollo del cinturón de cirrípedos. De este modo, se pretende dotar a los planes de seguimiento ambiental, tanto del abra de Bilbao como de otras áreas similares, de una herramienta para la detección de cambios en sus planes de recuperación.Instituto Español de Oceanografí

    Detection of blaCTX-M-15 in an integrative and conjugative element in four extensively drug-resistant Haemophilus parainfluenzae strains causing urethritis

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    Haemophilus parainfluenzae is a commensal organism with rising numbers of multidrug-resistant (MDR) strains. This pathogen is of increasing clinical relevance in urogenital infection. The aim of this work was to identify and characterise the molecular mechanisms of resistance associated with four cephalosporin-resistant H. parainfluenzae strains collected from patients with urethritis. Antimicrobial resistance was determined by microdilution following European Committee on Antimicrobial Susceptibility Testing cri-teria. Strains were then analysed by whole-genome sequencing to determine clonal relationship and the molecular basis of antimicrobial resistance. Finally, a phylogenetic analysis was performed on all urogen-ital MDR strains of H. parainfluenzae previously isolated in our hospital. All strains were resistant to ,B- lactams, macrolides, tetracycline, fluoroquinolones, chloramphenicol, cotrimoxazole, and aminoglycosides. The resistance profile was compatible with the presence of an extended-spectrum ,B-lactamase (ESBL). Whole-genome sequencing detected blaCTX-M-15 that conferred high minimum inhibitory concentrations to cephalosporins in two novel integrative and conjugative elements (ICEHpaHUB6 and ICEHpaHUB7) that also harboured a blaTEM-1 ,B-lactamase. This study shows a novel bla CTX-M-15 ESBL carried in an integrative conjugative element in four extensively drug-resistant H. parainfluenzae strains. This resistance determi-nant could be transmitted to other sexually transmitted pathogens and this is a cause for concern. (c) 2023 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/

    Morphodynamic Study of a 2018 Mass-Stranding Event at Punta Umbria Beach (Spain): E ect of Atlantic Storm Emma on Benthic Marine Organisms

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    Very few mass stranding events of invertebrates have been reported. In this paper, we report a mass stranding of multiple benthic organisms occurred at Punta Umbría beach (S Spain) after the passage of storm Emma (28 February to 5 March 2018). The most abundant organisms were identified, and exceptional meteorological and oceanographic events were analyzed, as a basis to understand the causes of stranding. The morphodynamic changes a ecting the beach profile during the storm were inferred using a cross shore depth-integrated and time averaged numerical model (CSHORE). Among the stranded species, decapods (Upogebia spp., Atelecyclus undecimdentatus), sipunculids (Sipunculus nudus), starfish (Astropecten sp.), and sessile tunicates were dominant. Storm Emma involved extreme significant wave heights of up to 7.27 m, low pressures, strong SW winds, precipitations and spring tides that modified the seabed elevation to depth as deep as 10 m. Simulations suggest that benthic organisms living at a water depth between 10 to 0.3 m were buried under a layer of sediment of up to ca. 10 cm deposited during the storm. This burial preceded the transport of intertidal and subtidal benthic organisms to the dry beach, causing their stranding. Impacts on the quality of habitat, biodiversity and the productivity of coastal ecosystems are discussed
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