Organochlorine compounds in tissues of swordfish (Xiphias gladius) from Mediterranean Sea and Azores islands     

Stefanelli P  Ausili A  Di Muccio A  Fossi C  Di Muccio S  Rossi S  Colasanti A 《Marine pollution bulletin》2004,49(11-12):938-950

Polychlorobiphenyls (PCB) and organochlorine (OC) pesticides are endocrine-disrupting chemicals (EDCs). The Italian Ministry of Environment has undertaken a program (1999-2001) to measure levels of contaminants in top marine predators and to develop sensitive biomarkers for the evaluation of toxicological risk in these species. In 1999, 15 swordfishes (Xiphias gladius) taken from the Mediterranean Sea along the Sicilian coast (Strait of Messina, Italy) and in the Atlantic Ocean along the Azores Islands, and analysed for 34 congeners of PCBs and 27 organochlorine (OC) pesticides in gonad, muscle, liver and blubber tissues. In the tissues of Mediterranean swordfishes the sum of the determined PCBs congeners ranged from 4.61 to 4651.17 ng g(-1) on fresh tissue basis. Among organochlorine pesticides DDE, DDT and DDD (TDE) predominated with an overall range of 2.37-4734.56 ng(-1) w.w. In particular p,p'-DDE had concentrations appearing up to 3900 ng(-1), with the highest values found in fatty tissues, such as blubber. In the liver of Azores Island swordfishes lower levels of summation PCBs (8.43-294.17 ng/g w.w.) and summation DDTs (<0.01-217.44 ng/g w.w.) were determined.  相似文献   

Le domaine Tariquide (arc de Gibraltar,Espagne et Maroc) : succession sédimentaire et événements structuraux au Lias et au Dogger     

Michel Durand-Delga  Silvia Gardin  Manuel Esteras  Hélène Paquet 《Comptes Rendus Geoscience》2005,337(8):787-798

The Lias–Dogger successions of the Tariquide units in the Gibraltar Arc differ from the series of tectonically adjacent units, the Penibetic (Iberia margin) and the Limestone ‘Dorsale’ (Alboran Domain). Lower Lias limestones are eroded and covered by the Domerian, which starts by deposits of open sea, continuous up to the Dogger (J. Musa-type successions), and elsewhere (Los Pastores-type successions) by a thin series (Upper Lias to Upper Dogger), starting by a manganesiferous episode (Ras Leona) and including marls deposited into three episodes, dated by calcareous nannofossils. Faulting events occurred before the Domerian and during the Late Toarcian (Los Pastores). To cite this article: M. Durand-Delga et al., C. R. Geoscience 337 (2005).  相似文献   

Mesospheric bore events in the equatorial middle atmosphere     

J. Fechine  A.F. Medeiros  R.A. Buriti  H. Takahashi  D. Gobbi 《Journal of Atmospheric and Solar》2005,67(17-18):1774

An all-sky CCD imager designed to measure wave structure of the OH, O₂b(0,1) and OI557.7 nm airglow emission layers in the mesosphere and lower thermosphere (MLT) region has been operated near the equatorial region at São João do Cariri (Cariri), Brazil, (7.5°S, 36.5°W). A large number of gravity wave was observed from September 2000 to September 2002 and among them 64 wave events were identified as mesospheric bores. The bore front shows a horizontal extension greater than 1000 km, and observed in the airglow layers as a complementary brilliance between the three emissions. At the first time mesospheric bore events were observed and analyzed in the equatorial region. Their predominant characteristics, occurrence, local time dependency, morphology and propagation direction will be presented and discussed.  相似文献   

Dicarinella imbricata (MORNOD 1949): First SEM documentation of the lost holotype and foraminiferal assemblage from the type horizon (Upper Cretaceous, Switzerland)     

Michele Caron  Silvia Spezzaferri 《Eclogae Geologicae Helvetiae》2006,99(3):295-299

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Importance of orographic precipitation to the water resources of Monteverde,Costa Rica     

Andrew J. Guswa  Amy L. Rhodes  Silvia E. Newell 《Advances in water resources》2007

Monteverde, Costa Rica harbors montane forests that exemplify the delicate balances among climate, hydrology, habitat, and development. Most of the annual precipitation to this region arrives during the wet season, but the importance of orographic precipitation during the dry and transitional seasons should not be underestimated. Development associated with ecotourism has put significant stress on water resources, and recent work has shown evidence that changes in regional land-cover and global climate may lead to reduced precipitation and cloud cover and a subsequent decline in endemic species.  相似文献   

Coronal Density Structures and CMEs: Superior Solar Conjunctions of Mars Express, Venus Express, and Rosetta: 2004, 2006, and 2008     

Martin Pätzold  Matthias Hahn  Silvia Tellmann  Bernd Häusler  Michael K. Bird  G. Leonard Tyler  Sami W. Asmar  Bruce T. Tsurutani 《Solar physics》2012,279(1):127-152

Coronal radio-sounding experiments were carried out using the S-band (2.3 GHz) and X-band (8.4 GHz) signals of the ESA Mars Express, Venus Express, and Rosetta spacecraft during five superior conjunctions occurring in 2004, 2006 (3×), and 2008/2009. Differential frequency and propagation delay (ranging) observations were recorded during these opportunities over the better part of a solar cycle, yielding information on the large-scale structure of the coronal electron-density distribution and its variations, including fluctuations on time scales from seconds to hours. These results concern primarily regions of slow solar wind because the radio propagation path is generally confined to the low heliolatitude regions by the conjunction. The mean frequency fluctuation and total electron content are determined as a function of heliocentric distance, and, with a few exceptions caused by streamers and CMEs, are found to be consistent with previous results from experiments on Ulysses. Dense coronal streamers and several coronal mass ejection (CME) events were identified in the radio-frequency data, some of which were observed in white light by the LASCO coronagraphs onboard SOHO. For those events with sufficient mutual coverage, good correlations are found between the electron-content fluctuations and structure imaged by the LASCO instrument.  相似文献   

Millennial-scale shifts in microtidal ecosystems during the Holocene: dynamics and drivers of change from the Po Plain coastal record (NE Italy)     

Veronica Rossi  Giulia Barbieri  Stefano Claudio Vaiani  Marco Cacciari  Luigi Bruno  Bruno Campo  Marco Marchesini  Silvia Marvelli  Alessandro Amorosi 《第四纪科学杂志》2021,36(6):961-979

Framed into a robust stratigraphic context, multivariate analyses on the Holocene palaeobiological record (pollen, benthic foraminifers, ostracods) of the Po coastal plain (NE Italy) allowed the investigation of microtidal ecosystems variability and driving parameters along a 35-km-long land–sea transect. Millennial-scale ecosystem shifts are documented by coeval changes in the meiofauna, reflecting variations in organic matter–water depth (shallow-marine environments) and degree of confinement-salinity (back-barrier settings). In-phase shifts of vegetation communities track unsteady water-table levels and river dynamics in freshwater palustrine areas. Five environmental–ecological stages followed one another crossing four tipping points that mark changes in relative sea level (RSL), climate and/or fluvial regime. At the culmination of Mediterranean RSL rise, after the 8200 event, remarkable growth of peatlands took place in the Po estuary, while low accumulation rates typified the shelf. At the transgressive–regressive turnaround (~7000 cal a bp ), the estuary turned into a delta plain with tidally influenced interdistributary embayments. River flow regime oscillations after the Climate Optimum (post-5000 cal a bp ) favoured isolation of the bays and the development of brackish wetlands surrounded by wooded peatlands. The youngest threshold (~800 cal a bp ), which led to the establishment of the modern delta, reflects a major avulsion of the Po River.  相似文献   

The Planktonic foraminifera <Emphasis Type="Italic">Globigerinoides eoconglobatus</Emphasis> n. sp. in a glacial–interglacial context: IODP359 Sites U1467 and U1468     

Stephanie Stainbank  Silvia Spezzaferri  Dick Kroon  Erica S. de Leau  Andres Rüggeberg 《Swiss Journal of Geoscience》2018,111(3):511-522

Here we define a new morphospecies of planktonic foraminifera Globigerinoides eoconglobatus n. sp., identified from International Ocean Discovery Program (IODP) expedition 359 samples from drift deposits of the Maldives, Inner Sea. Through biostratigraphic analysis, we infer it may be the direct ancestor of Globigerinoides conglobatus evolving from Globigerinoides obliquus in the Late Miocene (Subzone M13a). Globigerinoides eoconglobatus n. sp. can be distinguished from G. conglobatus through both its morphological traits and stable isotopic signature (δ¹⁸O and δ¹³C) in pre-adult and adult specimens. The most defining characteristic being its aperture height (AH). A variance in adult stable isotopic signals shows a possible difference in life strategies, possibly related to symbionts (presence/absence or concentration) and/or depth habitat. This work also tentatively shows G. eoconglobatus n. sp. and G. conglobatus abundances are linked to glacial–interglacial stages. Its low abundances and similarities to its descendent Globigerinoides conglobatus has likely accounted for it being unreported, until present, in both modern and fossil studies.  相似文献   

Presence of plastic debris in loggerhead turtle stranded along the Tuscany coasts of the Pelagos Sanctuary for Mediterranean Marine Mammals (Italy)     

Tommaso Campani  Matteo Baini  Matteo Giannetti  Fabrizio Cancelli  Cecilia Mancusi  Fabrizio Serena  Letizia Marsili  Silvia Casini  Maria Cristina Fossi 《Marine pollution bulletin》2013

This work evaluated the presence and the frequency of occurrence of marine litter in the gastrointestinal tract of 31 Caretta caretta found stranded or accidentally bycaught in the North Tyrrhenian Sea. Marine debris were present in 71% of specimens and were subdivided in different categories according to Fulmar Protocol (OSPAR 2008). The main type of marine debris found was user plastic, with the main occurrence of sheetlike user plastic. The small juveniles showed a mean ± SD of marine debris items of 19.00 ± 23.84, while the adult specimens showed higher values of marine litter if compared with the juveniles (26.87 ± 35.85). The occurrence of marine debris observed in this work confirms the high impact of marine debris in the Mediterranean Sea in respect to other seas and oceans, and highlights the importance of Caretta caretta as good indicator for marine litter in the Marine Strategy Framework Directive (MSFD) of European Union.  相似文献   

Particulate Thiol Peptides Along a Salinity Gradient of a Metal-Contaminated Estuary     

Silvia K. Kawakami  Eric P. Achterberg 《Estuaries and Coasts》2012,35(2):658-664

The thiol peptide phytochelatins (PC2; the polymer with n = 2) are efficient metal-chelating compounds produced by phytoplankton and higher plants. Both PC2 and their precursor glutathione (GSH) are related to detoxification mechanisms. GSH and PC2 were quantified using liquid chromatography with fluorescent detection and observed in the particulate phase along a salinity gradient of the Tamar Estuary (SW UK), a heavily metal impacted site, at concentrations up to 274 and 16.5 μmol (g chl a)⁻¹, respectively. The peptides predominated within low (0–5) and mid-salinities (5–20). Down-estuary, at sites farther from metal sources and salinities higher than 20, PC2 showed a sharp decrease or were not detected. High PC2/GSH ratios indicated areas with augmented concentrations of bioavailable metals at the tidal limit, near Cu mines and the mid-estuary where resuspension of sediments occurs. By following typical partitioning patterns previously reported for dissolved Cu and Zn, the production of thiol peptides, notably PC2, reflected a rapid interaction between the particulate and dissolved phases.  相似文献