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21.
Daniele Andronico Stefano Branca Sonia Calvari Michael Burton Tommaso Caltabiano Rosa Anna Corsaro Paola Del Carlo Gaetano Garfì Luigi Lodato Lusia Miraglia Filippo Murè Marco Neri Emilio Pecora Massimo Pompilio Guiseppe Salerno Letizia Spampinato 《Bulletin of Volcanology》2005,67(4):314-330
The 2002–03 Mt Etna flank eruption began on 26 October 2002 and finished on 28 January 2003, after three months of continuous explosive activity and discontinuous lava flow output. The eruption involved the opening of eruptive fissures on the NE and S flanks of the volcano, with lava flow output and fire fountaining until 5 November. After this date, the eruption continued exclusively on the S flank, with continuous explosive activity and lava flows active between 13 November and 28 January 2003. Multi-disciplinary data collected during the eruption (petrology, analyses of ash components, gas geochemistry, field surveys, thermal mapping and structural surveys) allowed us to analyse the dynamics of the eruption. The eruption was triggered either by (i) accumulation and eventual ascent of magma from depth or (ii) depressurisation of the edifice due to spreading of the eastern flank of the volcano. The extraordinary explosivity makes the 2002–03 eruption a unique event in the last 300 years, comparable only with La Montagnola 1763 and the 2001 Lower Vents eruptions. A notable feature of the eruption was also the simultaneous effusion of lavas with different composition and emplacement features. Magma erupted from the NE fissure represented the partially degassed magma fraction normally residing within the central conduits and the shallow plumbing system. The magma that erupted from the S fissure was the relatively undegassed, volatile-rich, buoyant fraction which drained the deep feeding system, bypassing the central conduits. This is typical of most Etnean eccentric eruptions. We believe that there is a high probability that Mount Etna has entered a new eruptive phase, with magma being supplied to a deep reservoir independent from the central conduit, that could periodically produce sufficient overpressure to propagate a dyke to the surface and generate further flank eruptions.Editorial responsibility: J. Donnelly-Nolan 相似文献
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Michael R. Talbot Niels Bo Jensen Tine Lærdal Maria Letizia Filippi 《Journal of Paleolimnology》2006,35(3):467-489
Bulk organic matter (OM) in sediments that accumulated in Lakes Victoria, Albert and Tanganyika during the major transgression
that transformed these basins from a desiccated or lowstand condition at the time of the Last Glacial Maximum to highstand
with overflow in the terminal Pleistocene and early Holocene, show some striking compositional trends. Sediment OM content
(TOC) and Rock-Eval Hydrogen Index (HI) both rise markedly, reflecting increasing primary productivity during the transgression
and enhanced conditions for the preservation of labile OM, In Lake Victoria rising sedimentary sulphur content tracks the
change in HI. Over the same time interval in all three lakes, δ13COM shows a falling trend of 5–8‰ . Nitrogen isotopic and C/N trends are, in contrast, more variable. Relatively high δ15N values at an early stage in the transgression may reflect isotopic effects associated with ammonia loss from an alkaline
waterbody, while high δ15N later in the transgression was probably due to periods when stratification-related denitrification had a particularly strong
impact upon the lakes' N cycle. The observed changes are attributed to the influence of the landscape drowned during the transgression
upon the nutrient budget of the lake, a rise in river-supplied nutrients as the climate became wetter, and an increasing tendency
to stable chemical stratification as the water column deepened. In the case of δ13C, additional contributory factors were changes in the amount and isotopic composition of river-supplied dissolved inorganic
carbon (DIC) as runoff and soil–moisture turnover rates increased, and the replacement of a C4-grassland dominated flora by
mixed woodland-grassland and forest with a significant presence of C3 plants. Distinct geochemical changes are also apparent
in Lakes Victoria and Albert sediments at the end of the transgression which are consistent with a reduction in nutrient loading.
In the case of N this resulted in biological N fixation becoming a major part of the lakes' N cycle, Some of the observed
geochemical variations may be generally applicable as proxy indicators of major transgressions in large lakes.
IDEAL Contribution No. 152. 相似文献
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Roberto Carlucci Lembo Giuseppe Maiorano Porzia Capezzuto Francesca Marano Chiara Alessandra Sion Letizia Spedicato Maria Teresa Ungaro Nicola Tursi Angelo Gianfranco D'Onghia 《Estuarine, Coastal and Shelf Science》2009,83(4):529-538
The spatial pattern of the nursery areas of red mullet (Mullus barbatus), hake (Merluccius merluccius) (Linnaeus, 1758) and deep-water rose shrimp (Parapenaeus longirostris) (Lucas, 1846) was studied in the South Adriatic and North Ionian Seas (Eastern-Central Mediterranean) applying geostatistical techniques and data from time series trawl surveys conducted in the area. The analysed variables were: R (number of recruits/km2) and R/Tot (fraction of recruits on the total sampled population). The structural analysis showed a spatial pattern of both variables characterized by continuity on a small scale. Predictions of nursery area localization with probability of finding recruits at different threshold values were obtained through median indicator kriging. For the red mullet the nurseries were mainly identified in the South Adriatic Sea off the Gargano peninsula and between Molfetta and Monopoli within 50 m in depth. The main concentration of hake juveniles was found to be between 100 and 200 m in depth along the Gargano peninsula and between Otranto and Santa Maria di Leuca, where a nursery of deep-water rose shrimp was also detected. An overlapping depth, between 100 and 200 m, was identified for hake and deep-water rose shrimp nurseries. Protection of these areas through limitations of fishing pressure is discussed. 相似文献
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The need to develop powerful tools to detect exposure and effects of POPs and emerging contaminants in Mediterranean cetaceans led us to develop a suite of sensitive non-lethal biomarkers in integument biopsies of free-ranging animals. In order to propose induction of CYP1A1 and CYP2B, detected by Western blot analysis, as biomarkers of exposure to OCs, PAHs and PBDEs, a three-phase experimental protocol (in vitro experiments, calibration experiments and field applications) was followed using fibroblast cell cultures and biopsies of Mediterranean Stenella coeruleoalba and Tursiops truncatus. This methodology was confirmed to be sensitive and stable in comparison to previous methods used to detect CYP1A1 in biopsies, enabling analysis of several inducible proteins in non-lethal samples and analysis of material from stranded animals. 相似文献
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Sartirana Davide Rotiroti Marco Bonomi Tullia De Amicis Mattia Nava Veronica Fumagalli Letizia Zanotti Chiara 《Hydrogeology Journal》2022,30(4):1157-1177
Hydrogeology Journal - The significant increase in urbanization has resulted in greater use of the subsurface in urban planning and, therefore, increased interaction between groundwater and... 相似文献
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Exploring composition and behaviour of fish fauna by in situ observations in the Bari Canyon (Southern Adriatic Sea,Central Mediterranean) 
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下载免费PDF全文 Gianfranco D'Onghia Francesca Capezzuto Angela Carluccio Roberto Carlucci Agnese Giove Francesco Mastrototaro Michele Panza Letizia Sion Angelo Tursi Porzia Maiorano 《Marine Ecology》2015,36(3):541-556
Canyons play a fundamental role in enhancing the abundance and diversity of marine organisms through the transport of organic matter and food resources, the presence of complex physical habitats and the absence of trawl fishing. During four baited lander deployments carried out in the Bari Canyon (Southern Adriatic Sea, Central Mediterranean), at depths of 443–788 m, about 43 h of video records were taken, for a total of 619,200 video frames. A total of 12 benthopelagic fish species (five chondrichthyes and seven osteichthyes) were identified. The blackspot seabream (Pagellus bogaraveo) was the most often observed fish species. The depth of 787 m represents a new depth record for this fish in the Adriatic Sea. Groups of up to 40 individuals of P. bogaraveo were attracted to the bait and were shown in single frames. The individuals were observed both exploring the area and feeding actively on the bait. The European conger (Conger conger) was recorded at each deployment. Clear scavenger behaviour was also observed in this teleost fish and in the shark Etmopterus spinax. The shark species Centrophorus granulosus and Hexanchus griseus, which are considered ‘vulnerable’ on the published IUCN Mediterranean Regional Red List, were also recorded but, although attracted by the bait, they were never seen feeding on it. Other fish species, harvested on fishing grounds, such as Merluccius merluccius, Helicolenus dactylopterus and Polyprion americanus, were also recorded. This study represents the first in situ documentation, at very low impact, of the fish fauna in the Bari Canyon, providing new insights into its small scale distribution and behaviour, the first in situ direct observation of the variable feeding behaviour of P. bogaraveo and its gregarious habits, as well as indicating that this canyon could act as a refuge area for species that are vulnerable to fishing on the open slope. 相似文献
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Alessandra?CellettiEmail author Letizia?Stefanelli Elena?Lega Claude?Froeschlé 《Celestial Mechanics and Dynamical Astronomy》2011,109(3):265-284
We perform an analysis of the dynamics of the circular, restricted, planar three-body problem under the effect of different
kinds of dissipation (linear, Stokes and Poynting–Robertson drags). Since the problem is singular, we implement a regularization
technique in the style of Levi–Civita. The effect of the dissipation is often to decrease the semi-major axis; as a consequence
the minor body collides with one of the primaries. In general, it is quite difficult to find non-collision orbits using random
initial conditions. However, by means of the computation of the Fast Lyapunov Indicators (FLI), we obtain a global view of
the dynamics. Precisely, we detect the regions of the phase space potentially belonging to basins of attraction. This investigation
provides information on the different regions of the phase space, showing both collision and non-collision trajectories. Moreover,
we find periodic orbit attractors for the case of linear and Stokes drags, while in the case of the Poynting–Robertson effect
no other attractors are found beside the primaries, unless a fourth body is added to counterbalance the dissipative effect. 相似文献
30.
Maurizio Maugeri Letizia Buffoni Barbara Delmonte Adriana Fassina 《Climatic change》2002,53(1-3):119-149
Daily meteorological observations have been made at the Brera astronomical observatory in Milan since 1763. Even if the data have always been collected at this observatory, the Milan series are far from being homogeneous as several changes were made to instruments, station location and observation methods. Within this context, the purpose of the paper is to discuss data homogenisation. Homogenisation is based both on objective information extracted from the station history (direct methodology) and on some statistical estimates (indirect methodology). Homogenisation by indirect methodology is mainly performed by comparison with other series whereas, if no other homogeneous series are available, it is based on the hypothesis that some statistics, such as the daily temperature range or the day to day variability, have no significant trends within some selected periods. Besides homogenisation also the completion of the series is discussed. Theresulting series are complete and homogenised daily minimum, mean and maximum temperatures and complete and homogenised daily mean pressures. They all cover the period 1763–1998. 相似文献