The contribution of marine geology to the knowledge of marine coastal environment off the Campania region (southern Italy): the geological map n. 502 “Agropoli” (southern Campania)     

Gemma Aiello  Ennio Marsella 《Marine Geophysical Researches》2013,34(2):89-113

The marine geological map n. 502 “Agropoli”, located offshore the Cilento Promontory, southern Italy, is here described and the regional geology interpreted, particularly referring to water depths between the 30 and 200 m isobaths. The geologic map has been constructed in the frame of a research program financed by the National Geological Survey of Italy (CARG Project), finalized to the construction of up-to-date cartography of the Campania region. Geological and geophysical data on the continental shelf and slope offshore of the Southern Campania region have been collected in the study area, bounded northwards by the Salerno Gulf and southwards by the Policastro Gulf. A high resolution multibeam bathymetry allowed for the construction of a marine digital elevation map; sidescan sonar profiles also have been collected and interpreted. The latter, merged to the bathymetry, have represented the base for the marine geologic cartography. The integrated geologic interpretation of seismic, bathymetric and sidescan sonar data has been calibrated by sea-bottom samples. The morpho-structures and the seismic sequences overlying the outcrops of acoustic basement reported in the cartographic representation have been studied in detail using single-channel seismics. The interpretation of seismic profiles has been a support for the reconstruction of the stratigraphic and structural setting of the Quaternary continental shelf successions and the outcrops of rocky acoustic basement in correspondence to the Licosa Cape morpho-structural high. These areas result from the seaward prolongation of the stratigraphic and structural units, widely cropping out in the surrounding emerged sector of the Cilento Promontory. The cartographic approach is based on the recognition of laterally coeval depositional systems, interpreted in the frame of the system tracts of the Late Quaternary depositional sequence. We present evidence of now subaqueous terraces inferred to be palaeoshorelines representing past sea-level positions and tentatively correlated these to oxygen isotopic stratigraphy.  相似文献   

Rural tourism in Spain: an analysis of recent evolution   总被引：6，自引：0，他引：6  

Gemma Cnoves  Montserrat Villarino  Gerda K. Priestley  Asuncin Blanco 《Geoforum》2004,35(6):755-769

The aim of this paper is to analyse the evolution of Rural Tourism¹ (RT) in Spain within a European context. The first step is to examine the development of different “models” of RT and trace some experiences of the application of European policy. In order to set the scene and understand this evolution, the collective imagery on which RT is based is also analysed. This is followed by a study of the development of tourist products and services in rural Spain since the 1980s, as diversification of the traditional sun/sand/sea (3S) tourist economy is sought. The analysis underlines the importance of the role of women, and the consequences of the activity for the economy of rural areas. The purpose is to identify differences in the pattern of evolution with more northern European countries, understand their causes and formulate recommendations for future development.  相似文献   

Effects of 17β-estradiol exposure in the mussel Mytilus galloprovincialis     

Gemma Janer  Ramon Lavado  Rmi Thibaut  Cinta Porte 《Marine environmental research》2004,58(2-5):443

Mussels Mytilus galloprovincialis were exposed to different concentrations of estradiol (20, 200, and 2000 ng/l) in a semi-static regime (1-day dosing intervals) for up to 7 days in an attempt to see how mussels dealt with exogenous estrogenic compounds. Sex hormone levels were determined in whole tissue. Free-estradiol was only significantly elevated at the highest exposure dose (up to 10-fold). Most of the estradiol was in the tissues as fatty acid esters (>78%), which sharply increased in a dose-dependent manner (from 4 ng/g in controls to 258 ng/g at the high exposure group). In contrast, neither free nor esterified testosterone levels showed significant differences between control and exposure groups. The results suggest the existence of mechanisms that allow mussels to maintain their hormonal status, and the important role that fatty acid esterification may play within those mechanisms. Synthesis and conjugation rates of estradiol were further investigated by measuring the activity of P450 aromatase, and palmitoyl-CoA:estradiol acyltransferase, in digestive gland microsomal fractions. Overall, the study contributes to the better knowledge of molluscan endocrinology, and defines new mechanisms of regulation of free steroid-levels in mussels.  相似文献   

Effects of 17beta-estradiol exposure in the mussel Mytilus galloprovincialis     

Janer G  Lavado R  Thibaut R  Porte C 《Marine environmental research》2004,58(2-5):443-446

Mussels Mytilus galloprovincialis were exposed to different concentrations of estradiol (20, 200, and 2000 ng/l) in a semi-static regime (1-day dosing intervals) for up to 7 days in an attempt to see how mussels dealt with exogenous estrogenic compounds. Sex hormone levels were determined in whole tissue. Free-estradiol was only significantly elevated at the highest exposure dose (up to 10-fold). Most of the estradiol was in the tissues as fatty acid esters (> 78%), which sharply increased in a dose-dependent manner (from 4 ng/g in controls to 258 ng/g at the high exposure group). In contrast, neither free nor esterified testosterone levels showed significant differences between control and exposure groups. The results suggest the existence of mechanisms that allow mussels to maintain their hormonal status, and the important role that fatty acid esterification may play within those mechanisms. Synthesis and conjugation rates of estradiol were further investigated by measuring the activity of P450 aromatase, and palmitoyl-CoA:estradiol acyltransferase, in digestive gland microsomal fractions. Overall, the study contributes to the better knowledge of molluscan endocrinology, and defines new mechanisms of regulation of free steroid-levels in mussels.  相似文献   

Linking pattern to process in reef sediment dynamics at Lady Musgrave Island,southern Great Barrier Reef   总被引：1，自引：0，他引：1       下载免费PDF全文

Sarah M. Hamylton  Rafael C. Carvalho  Stephanie Duce  Chris M. Roelfsema  Ana Vila‐Concejo 《Sedimentology》2016,63(6):1634-1650

Linking surficial sediment patterns in reef environments to the processes that underlie their depositional dynamics enables predictions to be made of how environmental changes will influence reef‐associated sedimentary landforms, such as islands and beaches. Geomorphic linkages between sediment deposition patterns and the biophysical processes that drive them are often poorly resolved, particularly at broad landscape scales where tangible statements can be made about structural changes to landforms. The present study applies geospatial techniques to link patterns in reef sediment dynamics at Lady Musgrave Island to the underlying processes driving them. In situ calcification is characterized by developing a high resolution map of the surficial calcium carbonate producing communities inhabiting the reef platform, and associated sediments across the reef flat are analysed for grain size, kurtosis, sorting and threshold bed shear stress to explore transport pathways across the reef flat and lagoon. Wave energy is modelled across the entire reef platform as a potential driver of sediment dynamics, and morphometric linkages are empirically defined between wave energy and grain size. Findings indicate that carbonate sediments are primarily sourced from calcifying communities colonizing the outer periphery of the reef platform and that sediment grain size can be reliably linked to wave energy by virtue of a linear model.  相似文献   

Influence of rock‐pool characteristics on the distribution and abundance of inter‐tidal fishes          下载免费PDF全文

Gemma E. White  Grant C. Hose  Culum Brown 《Marine Ecology》2015,36(4):1332-1344

Rock pools can be found in inter‐tidal marine environments worldwide; however, there have been few studies exploring what drives their, fish species composition, especially in Australia. The rock‐pool environment is highly dynamic and offers a unique natural laboratory to study the habitat choices, physiological limitations and adaptations of inter‐tidal fish species. In this study rock pools of the Sydney region were sampled to determine how the physical (volume, depth, rock cover and vertical position) and biological (algal cover and predator presence) parameters of pools influence fish distribution and abundance. A total of 27 fish species representing 14 families was observed in tide pools at the four study locations. The five most abundant species were Bathygobius cocosensis, Centropogon australis, Enneapterygius atrogulare, Lepidoblennius haplodactylus and Microcanthus strigatus, which together represented 71% of the total number of fish recorded. Larger rock pools containing more algal and rock ledge cover hosted a larger and more diverse population of fish. Furthermore, certain species were only found in pools with specific characteristics, such as the presence of loose shells, a variety algae or rock cover, suggesting a high degree of habitat specificity. By contrast, some species were ubiquitous and thus can likely tolerate a wide variety of physical conditions.  相似文献   

Survival of the Jovian planets with the Sun a Red Giant     

Samuel C. Vila 《Earth, Moon, and Planets》1985,33(3):219-221

The survival of the Jovian planets and their satellites as the Sun becomes a Red Giant is considered. It is found that the Jovian planets would not lose any matter - not even hydrogen. The satellites would lose their gaseous or volatile envelopes. Their rocky cores would resist melting and survive. Both the planets and the satellites would be unsuited to support human life.  相似文献   

Survival of the Earth and the future evolution of the Sun     

Samuel C. Vila 《Earth, Moon, and Planets》1984,31(3):313-315

The question of the survival of the planet Earth as the Sun becomes a red giant and possibly a planetary nebula depends on the maximum extent of the Sun's envelope. This study shows that if the Earth is reached by this envelope, it will be destroyed; but if it is not, it will survive. Present stellar evolution calculations imply that the Earth will be destroyed.  相似文献   

The ROSAT International X-ray/Optical Survey (RIXOS): source catalogue     

K. O. Mason  F. J. Carrera  G. Hasinger  H. Andernach  A. Aragon-Salamanca  X. Barcons  R. Bower  W. N. Brandt  G. Branduardi-Raymont  J. Burgos-Martín  F. Cabrera-Guerra  R. Carballo  F. Castander  R. S. Ellis  J. I. González-Serrano  E. Martínez-González  J. M. Martín-Mirones  R. G. McMahon  J. P. D. Mittaz  K. L. Nicholson  M. J. Page  I. Pérez-Fournon  E. M. Puchnarewicz  E. Romero-Colmenero  A. D. Schwope  B. Vila  M. G. Watson  D. Wonnacott 《Monthly notices of the Royal Astronomical Society》2000,311(3):456-484

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Analysis of the Temporal Occurrence of Seismicity at Deception Island (Antarctica). A Nonlinear Approach   总被引：1，自引：0，他引：1  

A. M. Correig  M. Urquizu  J. Vila  J. Marti 《Pure and Applied Geophysics》1997,149(3):553-574

—Deception Island is characterized by small magnitude local events with constant energy flux and very low stress drop. To obtain information about its origin, an interevent time series of 546 events, corresponding to an observational period of two month, has been analyzed. From a statistical point of view, data satisfies a Weibull distribution and presents clustering. A rescaled range analysis reveals that data are not independent, i.e. have memory, and the correlation dimension saturates at 2.2; as a consequence, the system can be modeled as a nonlinear iterative equation with three degrees of freedom that presents chaotic behavior. Taking into account that the average interevent time is of the order of 130 minutes, too short to be only due to tectonic activity, the above results indicate that some other mechanism may coexist with the regional tectonic one. According to several geological and geophysical observations, we suggest that most of the local events may be originated by pressure waves generated by a sudden change of phase, of sea and fresh water infiltrated into the main fractures and faults and also from shallow and confined water-saturated layers.  相似文献