Ecological evaluation of an experimental beneficial use scheme for dredged sediment disposal in shallow tidal waters     

van der Wal D  Forster RM  Rossi F  Hummel H  Ysebaert T  Roose F  Herman PM 《Marine pollution bulletin》2011,62(1):99-108

An experiment was performed to test an alternative dredging strategy for the Westerschelde estuary. Clean sand dredged from the navigation channel was disposed seawards of an eroding intertidal flat in order to modify morphology and hydrodynamics, improving the multi-channel system with ecologically productive shallow water habitat. Five years of intensive monitoring revealed that part of the disposed sediment moved slowly towards the flat, increasing the very shallow subtidal and intertidal area, as planned. The sand in the impact zone became gradually finer after disposal, possibly due to reduced current velocities. Nevertheless, no changes in macrobenthic biomass, density, species richness and composition were detected in the subtidal zone, also demonstrating rapid macrobenthic recovery. In the intertidal zone, no ecological effects could be revealed superimposed on trends associated with long-term sediment fining. Thus, despite morphological success and absence of detected negative ecological impacts of the experiment, new beneficial habitat was not created.  相似文献   

Seismic characterization of rigid sites in the ITACA database by ambient vibration monitoring and geological surveys     

Domenico Pileggi  David Rossi  Enrico Lunedei  Dario Albarello 《Bulletin of Earthquake Engineering》2011,9(6):1839-1854

The problem of seismic characterization of rock-mass or stiff-soil outcrops by the use of passive seismic prospecting techniques is discussed. Difficulties in the application of this kind of procedure in the presence of rugged morphology, high surface wave velocities and low ambient vibration powers, typical of stiff-soil/rock-mass sites are examined. A methodology to face these problems is here proposed, which is based on the strict synergy of detailed geologic surveys and application of robust seismic prospecting techniques, jointly considering single-station and multi-station tools. The application of this approach for the characterization of a number of sites belonging to the Italian Accelerometric Network is described, focusing on two representative case histories.  相似文献   

The application of foraminifera to reconstruct the rate of 20th century sea level rise, Morbihan Golfe, Brittany, France     

Veronica Rossi  Benjamin P. Horton  Eduardo Leorri  Bruce C. Douglas 《Quaternary Research》2011,75(1):24-35

Foraminiferal assemblages preserved within salt-marsh sediment can provide an accurate and precise means to reconstruct relative sea level due to a strong relationship with elevation, which can be quantified using a transfer function. We collected a set of surface samples from two salt marshes in the Morbihan Golfe, France to determine foraminiferal distribution patterns. Dominant taxa included Jadammina macrescens, Trochammina inflata, Haplophragmoides spp. and Miliammina fusca. We developed a foraminifera-based transfer function using a modern training set of 36 samples and 23 species. The strong relationship between observed and predicted values (r²_jack = 0.7) indicated that foraminiferal distribution is primarily controlled by elevation with respect to the tidal frame and precise reconstructions of former sea level are possible (RMSEP_jack = 0.07 m). The application of the transfer function to a short salt-marsh core (0.32 m) allowed the reconstruction of former sea levels, which were placed in a chronological framework using short-lived radionuclides (²¹⁰Pb and ¹³⁷Cs). The agreement between the foraminifera-based sea level curve and the Brest tide-gauge record confirms the reliability of transfer function estimates and the validity of this methodology to extend sea level reconstructions back into the pre-instrumental period. Both instrumental and microfossil records suggest an acceleration of sea level rise during the 20th century.  相似文献   

Neutron-loaded outflows in gamma-ray bursts     

Elena M. Rossi  rei M. Beloborodov  Martin J. Rees 《Monthly notices of the Royal Astronomical Society》2006,369(4):1797-1807

The force-free limit of magnetohydrodynamics (MHD) is often a reasonable approximation to model black hole and neutron star magnetospheres. We describe a general relativistic force-free (GRFFE) formulation that allows general relativistic magnetohydrodynamic (GRMHD) codes to directly evolve the GRFFE equations of motion. Established, accurate and well-tested conservative GRMHD codes can simply add a new inversion piece of code to their existing code, while continuing to use all the already-developed facilities present in their GRMHD code. We show how to enforce the   E · B = 0  constraint and energy conservation, and we introduce a simplified general model of the dissipation of the electric field to enforce the   B ²− E ² > 0  constraint. We also introduce a simplified yet general method to resolve current sheets, without much reconnection, over many dynamical times. This formulation is incorporated into an existing GRMHD code ( harm ), which is demonstrated to give accurate and robust GRFFE results for Minkowski and black hole space–times.  相似文献   

The Crati Submarine Fan, Ionian Sea     

Franco Ricci Lucchi  Albina Colella  Gianni Gabbianelli  Sergio Rossi  William R. Normark 《Geo-Marine Letters》1984,3(2-4):71-77

The Crati Fan is located in the tectonically active submerged extension of the Apennines chain and foretrough. The small fan system is growing in a relatively shallow (200 to 450 m), elongate nearshore basin receiving abundant input from the Crati River. The fan is characterized by a short, steep, channelized section (inner or upper fan) and a smooth, slightly bulging distal section (outer or lower fan). The numerous subparallel channels head in the shelf or littoral zone and do not form branching distributary patterns. Sand and mud depositional lobes of the outer fan stretch over more than 60% of fan length. Margin setting represents fan and/or source area  相似文献   

The redshift distribution of Swift gamma-ray bursts: evidence for evolution     

Frédéric Daigne  Elena M. Rossi †  Robert Mochkovitch 《Monthly notices of the Royal Astronomical Society》2006,372(3):1034-1042

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The polarization of afterglow emission reveals γ-ray bursts jet structure     

Elena M. Rossi  Davide Lazzati  Jay D. Salmonson  Gabriele Ghisellini 《Monthly notices of the Royal Astronomical Society》2004,354(1):86-100

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Geospatial web services pave new ways for server-based on-demand access and processing of Big Earth Data     

Julia Wagemann  Oliver Clements  Ramiro Marco Figuera  Angelo Pio Rossi  Simone Mantovani 《International Journal of Digital Earth》2018,11(1):7-25

ABSTRACT

Big Earth Data has experienced a considerable increase in volume in recent years due to improved sensing technologies and improvement of numerical-weather prediction models. The traditional geospatial data analysis workflow hinders the use of large volumes of geospatial data due to limited disc space and computing capacity. Geospatial web service technologies bring new opportunities to access large volumes of Big Earth Data via the Internet and to process them at server-side. Four practical examples are presented from the marine, climate, planetary and earth observation science communities to show how the standard interface Web Coverage Service and its processing extension can be integrated into the traditional geospatial data workflow. Web service technologies offer a time- and cost-effective way to access multi-dimensional data in a user-tailored format and allow for rapid application development or time-series extraction. Data transport is minimised and enhanced processing capabilities are offered. More research is required to investigate web service implementations in an operational mode and large data centres have to become more progressive towards the adoption of geo-data standard interfaces. At the same time, data users have to become aware of the advantages of web services and be trained how to benefit from them most.  相似文献   

Environmental tracers and indicators bringing together groundwater,surface water and groundwater-dependent ecosystems: importance of scale in choosing relevant tools     

G. Bertrand  D. Siergieiev  P. Ala-Aho  P. M. Rossi 《Environmental Earth Sciences》2014,72(3):813-827

Groundwater–surface water (GW–SW) interactions cover a broad range of hydrogeological and biological processes and are controlled by natural and anthropogenic factors at various spatio-temporal scales, from watershed to hyporheic/hypolentic zone. Understanding these processes is vital in the protection of groundwater-dependent ecosystems increasingly required in water resources legislation across the world. The use of environmental tracers and indicators that are relevant simultaneously for groundwater, surface water and biocenoses–biotope interactions constitutes a powerful tool to succeed in the management task. However, tracer type must be chosen according to the scale of interest and tracer use thus requires a good conceptual understanding of the processes to be evaluated. This paper reviews various GW–SW interaction processes and their drivers and, based on available knowledge, systemises application of conservative tracers and semi-conservative and reactive environmental indicators at different spatial scales. Biocenoses–biotopes relationships are viewed as a possible transition tool between scales. Relation between principal application of the environmental tracers and indicators, examples and guidelines are further proposed for examining GW–SW interactions from a hydrogeological and biological point of view by demonstrating the usability of the tracers/indicators and providing recommendations for the scientific community and decision makers.  相似文献   

Multi-methodological investigation of kunzite, hiddenite, alexandrite, elbaite and topaz, based on laser-induced breakdown spectroscopy and conventional analytical techniques for supporting mineralogical characterization     

Manuela Rossi  Marcella Dell’Aglio  Alessandro De Giacomo  Rosalba Gaudiuso  Giorgio Saverio Senesi  Olga De Pascale  Francesco Capitelli  Fabrizio Nestola  Maria Rosaria Ghiara 《Physics and Chemistry of Minerals》2014,41(2):127-140

Gem-quality alexandrite, hiddenite and kunzite, elbaite and topaz minerals were characterized through a multi-methodological investigation based on EMPA-WDS, LA-ICP-MS, and laser-induced breakdown spectroscopy (LIBS). With respect to the others, the latter technique enables a simultaneous multi-elemental composition without any sample preparation and the detection of light elements, such as Li, Be and B. The criteria for the choice of minerals were: (a) the presence of chromophore elements in minor contents and/or as traces; (b) the presence of light lithophile elements (Li, Be and B); (c) different crystal chemistry complexity. The results show that LIBS can be employed in mineralogical studies for the identification and characterization of minerals, and as a fast screening method to determine the chemical composition, including the chromophore and light lithophile elements.  相似文献