53 research outputs found

    Use of ecological indices to assess the health status of Posidonia oceanica meadows in Eastern Liguria.

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    Posidonia oceanica (L.) Delile is an endemic Mediterranean seagrass and a key species of coastal marine ecosystems listed among the priority habitats in the European Directive 92/43 / EEC. P. oceanica is a good biological indicator to define the quality of coastal marine ecosystem, because its high sensitivity to environmental conditions changes. The aim of this study is 1) to investigate if the health status of some P.oceanica meadows located in different sites influences the ability of the system to stock natural capital and 2) to quantify changes in natural capital value in both biophysical and monetary terms. Health status of five different meadows along Liguria coast was evaluated by means of different indicators such as: Conservation Index, Substitution Index, Phase Shift Index and Posidonia Rapid Easy Index. Natural capital has been assessed through emergy analysis, a biophysical approach able to account the resources directly and indirectly used up to reach a certain product or mantain a system. Results showed that healthier meadows are located in marine protected areas or far from main sources of anthropic pressures and that higher values of natural capital is stored in healthy seagrass

    Consequences of the marine climate and ecosystem shift of the 1980-90s on the Ligurian Sea biodiversity (NW Mediterranean Sea)

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    A rapid temperature increase in the 1980-90s has been accompanied by dramatic and unprecedented changes in the biota and communities of the Ligurian Sea. This review uses existing historical series (a few of which have been purposely updated) to assess extent and consequences of such changes. A number of warm-water species, previously absent or occasional in the comparatively cold Ligurian Sea, has recently established thanks to warmer winters. Occurrence among them of invasive alien species is causing concern because of their capacity of outcompeting autochthonous species. Summer heatwaves, on the other hand, caused mass mortalities in marine organisms, some of which found refuge at depth. New marine diseases appeared, as well as other dysfunctions such as the formation of mucilage aggregates that suffocated and entangled benthic organisms. Human pressures have combined with climate change to cause phase shifts (i.e., abrupt variations in species composition and community structure) in different habitats, such as the pelagic environment, seagrass meadows, rocky reefs, and marine caves. These phase shifts implied biotic homogenization, reduction of diversity, and dominance by invasive aliens, and may be detrimental to the resilience of Ligurian Sea ecosystems. Another phase of rapid warming has possibly started in the 2010s and there are clues pointing to a further series of biological changes, but data are too scarce to date for proper assessment. Only well addressed long-term studies will help understanding the future dynamics of Ligurian Sea ecosystems and their possibilities of recovery

    Guidelines for Posidonia oceanica restoration

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    Report Cooperation agreement Mediterranean Posidonia Network (MPN), French Biodiversity Agency (OFB) & University of Corsica Pasquale Paoli (UCPP) N°OFB-22-1310: 29 p. + Appendices.Peer reviewe

    Recarga artificial en Bajos Submeridionales

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    Se presenta la experiencia en desarrollo en un sector de Bajos Submeridionales próximo a Tostado, para monitorear los efectos de la recarga artificial de acuíferos. El objetivo del estudio es mejorar la disponibilidad de agua en calidad y cantidad para uso ganadero y evaluar una obra de recarga a partir de un pozo doble propósito recarga – bombeo para mejorar su eficiencia, y difundir estas prácticas.El área piloto se ubica en un paleocauce arenoso del río Salado. En el mismo se han realizado numerosos estudios geoeléctricos, de infiltración, sedimentológicos, químicos recuperación de niveles, de suelos y de recarga. Además se dispone de una estación meteorológica automática, caudalímetro y freatímetros. Se realizó un análisis de eventos de recarga y su efecto sobre el sistema natural y en la obra. Se concluye que ha resultado exitosa y puede ser transferida a otros ambientes de paleocauces del chaco-santafesino.This work describes an artificial recharge experience of groundwater as source for animal beverage, de veloped on a livestock demonstrative unit, placed in Bajos Submeridionales, Santa Fe province, Argentina. The aim of this study is to improve quality and quantity of water for livestock use, analyze a recharge-pumping well efficiency, and finally to spread this practice in the region. The study area is located in a antique sandy channel of the Salado river, where have been conducted geoelectric studies, sedimentologic, soil and water analysis, pumping and recharge, and infiltration tests. Additionally, it counts with metheorological on-line data from an automatic station, flowmeter, and water-level measurements from digital and analogical devises. An analysis of a recharge event has been conducted in order to assess environmental changes and response of facilities. This successful experience suggests that these kinds of facilities could be applied in similar environments of chaco-santafesino region.Universidad Nacional de La Plat

    Language production impairments in patients with a first episode of psychosis

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    The 2014-2017 outburst of the young star ASASSN-13db: A time-resolved picture of a very low-mass star between EXors and FUors

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    ASASSN-13db is a M5-type star with a protoplanetary disk, the lowest mass star known to experience accretion outbursts. Since its discovery in 2013, it has experienced two outbursts, the second of which started in November 2014 and lasted until February 2017. We use high- and low-resolution spectroscopy and time-resolved photometry from the ASAS-SN survey, the LCOGT and the Beacon Observatory to study the lightcurve and the dynamical and physical properties of the accretion flow. The 2014-2017 outburst lasted for nearly 800 days. A 4.15d period in the lightcurve likely corresponds to rotational modulation of a star with hot spot(s). The spectra show multiple emission lines with variable inverse P-Cygni profiles and a highly variable blueshifted absorption below the continuum. Line ratios from metallic emission lines (Fe I/Fe II, Ti I/Ti II) suggest temperatures of \sim5800-6000 K in the accretion flow. Photometrically and spectroscopically, the 2014-2017 event displays an intermediate behavior between EXors and FUors. The accretion rate (\.{M}=1-3×\times107^{-7}M_\odot/yr), about 2 orders of magnitude higher than the accretion rate in quiescence, is not significantly different from the accretion rate observed in 2013. The absorption features in the spectra suggest that the system is viewed at a high angle and drives a powerful, non-axisymmetric wind, maybe related to magnetic reconnection. The properties of ASASSN-13db suggest that temperatures lower than those for solar-type stars are needed for modeling accretion in very low-mass systems. Finally, the rotational modulation during the outburst reveals that accretion-related structures settled after the begining of the outburst and can be relatively stable and long-lived. Our work also demonstrates the power of time-resolved photometry and spectroscopy to explore the properties of variable and outbursting stars. (Abridged)

    A multi-element psychosocial intervention for early psychosis (GET UP PIANO TRIAL) conducted in a catchment area of 10 million inhabitants: study protocol for a pragmatic cluster randomized controlled trial

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    Multi-element interventions for first-episode psychosis (FEP) are promising, but have mostly been conducted in non-epidemiologically representative samples, thereby raising the risk of underestimating the complexities involved in treating FEP in 'real-world' services
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