155 research outputs found

    Unraveling Past Submarine Eruptions by Dating Lapilli Tuff-Encrusting Coralligenous (Actea Volcano, NW Sicilian Channel)

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    none7noThe dating of young submarine volcanic eruptions, with their potential generation of tsunamigenic waves, is essential for a reliable hazard assessment. This is particularly relevant in highly populated coastal areas. The scarce knowledge of the underwater environment makes however, this reconstruction challenging. Our study is focused on the NW sector of the Sicilian Channel, where several small- and medium-size volcanic edifices are present. The only documented Surtseyan-type eruption occurred in A.D. 1831, forming the ephemeral Ferdinandea Island. Late Pleistocene to mid-Holocene eruptions have been up to now only hypothesized, and based solely on indirect data. Here we present the first radiocarbon dates of a coralligenous bioconstruction sampled at 34 m water depth from the summit of the Actea volcano, grown up progressively (up to nowadays) on a lapilli tuff deposit. Actea volcano is a recently discovered pyroclastic cone located at only four nautical miles off the SW coast of Sicily. The oldest age of the bioconstructions that started to encrustate the shallow water pyroclastics shortly after their emplacement (7,387 ± 175 cal years B.P.) represents a terminus ante quem, thus testifying a mid-Holocene submarine eruption in this sector of the Sicilian Channel. This method may be effectively used to bridge the gap between historical accounts and the geological record and thus may contribute to a better volcanic hazard assessment of submarine eruption and related phenomena such as tsunamis.openLodolo E.; Renzulli A.; Cerrano C.; Calcinai B.; Civile D.; Quarta G.; Calcagnile L.Lodolo, E.; Renzulli, A.; Cerrano, C.; Calcinai, B.; Civile, D.; Quarta, G.; Calcagnile, L

    Radiocarbon Dating of Marine Samples: Methodological Aspects, Applications and Case Studies

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    none4Radiocarbon dating by AMS (Accelerator Mass Spectrometry) is a well-established absolute dating technique widely used in different areas of research for the analysis of a wide range of organic materials. Precision levels of the order of 0.2–0.3% in the measured age are nowadays achieved while several international intercomparison exercises have shown the high degree of reproducibility of the results. This paper discusses the applications of 14C dating related to the analysis of samples up-taking carbon from marine carbon pools such as the sea and the oceans. For this kind of samples relevant methodological issues have to be properly addressed in order to correctly interpret 14C data and then obtain reliable chronological frameworks. These issues are mainly related to the so-called “marine reservoirs effects” which make radiocarbon ages obtained on marine organisms apparently older than coeval organisms fixing carbon directly from the atmosphere. We present the strategies used to correct for these effects also referring to the last internationally accepted and recently released calibration curve. Applications will be also reviewed discussing case studies such as the analysis of marine biogenic speleothems and for applications in sea level studies.openGianluca Quarta; Lucio Maruccio; Marisa D’Elia; Lucio CalcagnileQuarta, Gianluca; Maruccio, Lucio; D'Elia, Marisa; Calcagnile, Luci

    Left ventricular mass and intrarenal arterial stiffness as early diagnostic markers in cardiorenal syndrome type 5 due to systemic sclerosis

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    Background: Cardiorenal syndrome type 5 (CRS-5) includes a group of conditions characterized by a simultaneous involvement of the heart and kidney in the course of a systemic disease. Systemic sclerosis (SSc) is frequently involved in the etiology of acute and chronic CRS-5 among connective tissue diseases. In SSc patients, left ventricular mass (LVM) can be used as a marker of nutritional status and fibrosis, while altered intrarenal hemodynamic parameters are suggestive of early kidney involvement. Methods: Forty-two consecutive patients with a diagnosis of SSc without cardiac and/or renal impairment were enrolled to assess whether cardiac muscle mass can be related to arterial stiffness. Thirty subjects matched for age and sex were also enrolled as healthy controls (HC). All patients performed echocardiography and renal ultrasound. Results: Doppler indices of intrarenal stiffness and echocardiographic indices of LVM were significantly increased in SSc patients compared to HC. A positive correlation exists between LVM/body surface area and pulsatile index (p < 0.05, r = 0.36), resistive index (p < 0.05, r = 0.33) and systolic/diastolic ratio (p < 0.05, r = 0.38). Doppler indices of intrarenal stiffness and LVM indices were significantly higher in SSc patients with digital ulcers than in SSc patients without a digital ulcer history. Conclusions: SSc is characterized by the presence of microvascular and multiorgan injury. An early cardiac and renal impairment is very common. LVM and intrarenal arterial stiffness can be considered as early markers of CRS onset. The clinical use of these markers permits a prompt identification of organ damage. An early diagnosis allows the appropriate setting of pharmacological management, by slowing disease progression

    The sub-fossil red coral of Sciacca (Sicily Channel, Mediterranean Sea): colony size and age estimates

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    AbstractThe Mediterranean red coral, Corallium rubrum (L.), has been a valuable economic resource for more than 2000 years. The Sicily Channel and surrounding areas are one of the most famous red coral fishing grounds of the whole region, hosting the deepest ever found living colonies and large sub-fossil red coral deposits; the so-called Sciacca banks are a unique location in the whole Mediterranean Sea. In this paper, a morphometric description of this sub-fossil population is presented for the first time from studies of colonies in the collection of several coral factories from Torre del Greco (Naples), with radiocarbon age estimations and growth rate evaluations. From the results of this study, after several thousand years Sciacca red coral colonies maintained the organic matrix structure with evident annual discontinuities, allowing estimations of the annual growth rate (about 0.3 mm/year) and the average population age (about 33.5 years). These resulting data are similar to the values determined for deep-dwelling living red coral populations. The radiocarbon dating evidenced a range of ages, from 8300 to 40 years before 1950 CE, mostly falling between 2700 and 3900 YBP, suggesting that colonies accumulated over a wide span of time. In view of the tectonically active nature of the area, several catastrophic events affected these ancient populations, maintaining them in a persistent state of early-stage, structurally similar to the those in current over-exploited areas

    Sand Ridges on Rocky Coastal Platforms as Markers of Tsunami Impact: A Multi-Disciplinary Analysis along the Ionian Coast of Southern Apulia (Italy)

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    Along the Ionian coast of Southern Apulia, a sand ridge has been detected at the inner border of a wide, low-elevated rocky platform. A multi-disciplinary analysis was carried out to define the main geomorphological and sedimentological features of this dune-like coastal deposit, to clarify its nature as well as to obtain chronological constraints for its development. The geomorphological survey reveals that the sand ridge is about 40\u201360 m wide, reaching a maximum elevation of 3.9 m above m.s.l., whereas its thickness can be estimated between 1.0 and 2.8 m. The sand ridge is in some places associated with large-size boulders. Grain size analysis shows that it is made up of poorly sorted coarse-medium sands with a gravelly fraction, without significant sedimentary structures, as confirmed by Ground Penetrating Radar survey. The micro and macro-faunal assemblage sampled in the sand ridge can be related to shallow-water environments with Posidonia oceanica meadows occurring offshore. The development of the studied sand ridge can be ascribed to a tsunami event able to mix up very coarse bioclastic sands placed at submerged platforms, storm beach deposits covering the low-elevated coastal platform in patches, and possibly older tsunami deposits. Accelerator Mass Spectrometry radiocarbon age determinations on mollusc shells sampled from the sand ridge span from 929\u20131168 AD to 1707\u20131950 AD and cluster around the 18th\u201319th centuries, suggesting a possible association with a recent tsunami event. Data reported in the Euro-Mediterranean Tsunami Catalogue would indicate as the most likely event that one of the 25th April 1836, produced by a strong earthquake with its epicenter near Rossano village, on the Ionian coast of the Calabria region

    The Longevity of Fruit Trees in Basilicata (Southern Italy): Implications for Agricultural Biodiversity Conservation

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    In the Mediterranean basin, agriculture and other forms of human land use have shaped the environment since ancient times. Intensive and extensive agricultural systems managed with a few cultured plant populations of improved varieties are a widespread reality in many Mediterranean countries. Despite this, historical cultural landscapes still exist in interior and less intensively managed rural areas. There, ancient fruit tree varieties have survived modern cultivation systems, preserving a unique genetic heritage. In this study, we mapped and characterized 106 living fruit trees of ancient varieties in the Basilicata region of southern Italy. Tree ages were determined through tree ring measurements and radiocarbon analyses. We uncovered some of the oldest scientifically dated fruit trees in the world. The oldest fruit species were olive (max age 680 +/- 57 years), mulberry (647 +/- 66 years), chestnut (636 +/- 66 years), and pear (467 +/- 89 years). These patriarchs hold a unique genetic resource; their preservation and genetic maintenance through agamic propagation are now promoted by the Lucan Agency for the Development and Innovation in Agriculture (ALSIA). Each tree also represents a hub for biodiversity conservation in agrarian ecosystems: their large architecture and time persistence guarantee ecological niches and micro-habitats suitable for flora and fauna species of conservation significance

    Autochthonous fermentation starters for the industrial production of Negroamaro wines

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    Abstract The aim of the present study was to establish a new procedure for the oenological selection of Saccharomyces cerevisiae strains isolated from natural must fermentations of an important Italian grape cultivar, denoted as "Negroamaro". For this purpose, 108 S. cerevisiae strains were selected as they did not produce H2S and then assayed by microfermentation tests. The adopted procedure made it possible to identify 10 strains that were low producers of acetic acid and hydrogen sulphide and showed that they completed sugar consumption during fermentation. These strains were characterized for their specific oenological and technological properties and, two of them, strains 6993 and 6920, are good candidates as industrial starter cultures. A novel protocol was set up for their biomass production and they were employed for industrial-scale fermentation in two industrial cellars. The two strains successfully dominated the fermentation process and contributed to increasing the wines' organoleptic quality. The proposed procedure could be very effective for selecting "company-specific" yeast strains, ideal for the production of typical regional wines. "Winery" starter cultures could be produced on request in a small plant just before or during the vintage season and distributed as a fresh liquid concentrate culture

    Radiocarbon dating of mortars from the baptismal font of the San Lorenzo cathedral of Alba (Cuneo, Italy):Comparison with thermoluminescence dating of related bricks and pipes

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    The San Lorenzo Cathedral of Alba is a Romanesque church (rebuilt in Gothic epoch) located in northwest Italy. Since 2007, this church has been subjected to renovations and archaeological excavations that led to the finding of the lower part of the basin and the water drainage pipe of a baptismal font of unknown age. Thermoluminescence and radiocarbon dating have been carried out respectively on some ceramic elements and lime mortar samples used in both the pipe and basin of the font. Thermoluminescence results suggest that some of the bricks may have been reused from previous structures while 14C results suggest that the font was built between the 9th and the 11th centuries AD, most probably in the 10th century AD

    Facies created by the yellow coral Dendrophyllia cornigera (Lamarck, 1816): Origin, substrate preferences and habitat complexity

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    The yellow coral Dendrophyllia cornigera (Lamarck, 1816) is a NE Atlantic-Mediterranean scleractinian. It is considered a typical hard bottom species, generally reported on outcropping rocks from mesophotic to upper bathyal depths. Several evidences suggest that this species is able to tolerate a broad range of temperatures, which allows it to colonize numerous environments in a wide depth range. In the present study, we first provided a detailed ecological characterization of the D. cornigera dense aggregation thriving on the Mantice Shoal (NW Ligurian Sea, Mediterranean Sea). Information on substrate type and inclination, average extension and density, colonies size-class frequency distribution and associated fauna are reported. Then, we presented an extensive review of the available information on the ecology of this species, including 142 new ROV records from the Italian coast (40–1820 m). Results indicated that D. cornigera occurs on a wide range of substrates, including soft bottoms and hardgrounds (outcropping rocks, coralligenous rock and dead cold-water coral frameworks), with significant differences in colony density and size among different substrates. Dendrophyllia cornigera creates three main facies, each characterized by a specific combination of substrate, inclination, depth, and associated fauna. Scattered living colonies, as well as large thanatocoenoses, display a wide geographical and bathymetric distribution. Differently, the facies represented by dense meadows on horizontal soft-bottoms results rare, being reported only from the Mantice Shoal and the Amendolara Bank (Ionian Sea). The radiocarbon age of the thanatocoenoses varies between 400 (Corsica Channel) and 13000 (Vercelli Seamount) years before present. This study highlights the wide adaptability of D. cornigera in terms of environmental settings, changing the current view on the ecology of this species and providing essential insights for the implementation of international deep-sea habitat classification schemes and conservation measures
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