An in-depth look at the lunar crater Copernicus: Exposed mineralogy by high-resolution near-infrared spectroscopy     

Roberto Bugiolacchi  Urs Mall  Susan McKenna-Lawlor  Kjell Brønstad  Finn Søraas  Rolf B. Pedersen 《Icarus》2011,213(1):43-63

Newly acquired, sequentially spaced, high-resolution near-infrared spectra across the central section of crater Copernicus’ interior have been analyzed using a range of complementary techniques and indexes.We have developed a new interpretative method based on a multiple stage normalization process that appears to both confirm and expand on previous mineralogical estimations and mapping. In broad terms, the interpreted distribution of the principle mafic species suggests an overall composition of surface materials dominated by calcium-poor pyroxenes and minor olivine but with notable exceptions: the southern rim displays strong ca-rich pyroxene absorption features and five other locations, the uppermost northern crater wall, opposite rim sections facing the crater floor, and the central peak Pk1 and at the foot of Pk3, show instead strong olivine signatures.We also propose impact glass an alternative interpretation to the source of the weak but widespread olivine-like spectral signature found in low-reflectance samples, since it probably represents a major regolith constituent and component in large craters such as Copernicus.The high quality and performance of the SIR-2 data allows for the detection of diagnostic key mineral species even when investigating spectral samples with very subdued absorption features, confirming the intrinsic high-quality value of the returned data.  相似文献   

Particulate organic matter uptake rates of two benthic filter-feeders (Sabella spallanzanii and Branchiomma luctuosum) candidates for the clarification of aquaculture wastewaters     

Cavallo D  Pusceddu A  Danovaro R  Giangrande A 《Marine pollution bulletin》2007,54(5):622-625

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Sulphate reduction in the sediment of the Venice canals (Italy)     

Zaggia L  Rosso J  Zonta R 《Marine pollution bulletin》2007,55(10-12):415-424

The sulphur cycle in the sediment of the Venice canal network was investigated by considering the sulphate reduction rate (SRR) and the distribution of sulphur compounds, in both pore water and sediment. Sulphate reduction (SR) is the main process in the metabolism of the organic matter supplied to the network by untreated urban effluents. Although it might account for the decomposition of only a limited percentage of the total organic-C inputs, the estimated rates are among the highest observed in coastal sediments. Measured rates range from 0.26 to 0.99 micromolcm(-3)d(-1), while mean annual values, estimated by a diagenetic model, vary from 0.16 to 0.43 micromolcm(-3)d(-1). The speciation of S in the sediment reveals that pyrite-S is the most abundant component of the total reduced S pool, whereas acid volatile sulphides and elemental sulphur together account for less than 45%. A preliminary budget indicates that the rate of burial of solid-phase S is small compared to the S produced by SR (from 10 to 25%). A large amount of reduced S is then lost from the canal deposits to be re-oxidised at the sediment-water interface or in the overlying water column.  相似文献   

A comparative analysis of three habitat suitability models for commercial yield estimation of Tapes philippinarum in a North Adriatic coastal lagoon (Sacca di Goro, Italy)   总被引：1，自引：0，他引：1  

Vincenzi S  Caramori G  Rossi R  De Leo GA 《Marine pollution bulletin》2007,55(10-12):579-590

Habitat Suitability (HS) models have been extensively used by conservation planners to estimate the spatial distribution of threatened species and of species of commercial interest. In this work we compare three HS models for the estimation of commercial yield potential and the identification of suitable sites for Tapes philippinarum rearing in the Sacca di Goro lagoon (Italy) on the basis of six environmental factors. The habitat suitability index (HSI) is based on expert opinion while the habitat suitability conditional (HSC) is calibrated on observational data. The habitat suitability mixed (HSM) model is a two-part model combining expert knowledge and regression analysis: the first component of the model uses logistic regression to identify the areas in which clams are likely to be present; the second part applies the same parameter-specific suitability functions of the HSI model only in the areas previously identified as productive by the logistic component. The HS models were validated on an independent data set and estimates of potential yield of the Goro lagoon were compared. The effectiveness of the three approaches is then discussed in terms of predicted yield and identification of suitable sites for farming.  相似文献   

Measuring and managing changes in estuaries and lagoons: morphological and eco-toxicological aspects   总被引：1，自引：0，他引：1  

Zonta R  Guerzoni S  Pérez-Ruzafa A  de Jonge VN 《Marine pollution bulletin》2007,55(10-12):403-406

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Alpine tectonics in the Calabrian–Peloritan belt (southern Italy): New 40Ar/39Ar data in the Aspromonte Massif area     

Thomas Heymes  Patrick Monié  Nicolas Arnaud  Arnaud Pêcher  Jean-Pierre Bouillin  Roberto Compagnoni 《Lithos》2010,114(3-4):451-472

This study provides new ⁴⁰Ar/³⁹Ar geochronological constraints on the age of the Alpine tectonics in the Aspromonte Massif (southern part of the Calabrian–Peloritan belt). This massif exposes the upper units of the Calabride Complex which originated from the European continental margin. The Calabride Complex was incorporated in the Alpine orogenic wedge and then integrated into the Apennines and Maghrebides fold-and-thrust belts. Throughout the Calabride Complex there is evidence for a two stage tectonic history, which remains however rather poorly dated: Alpine nappe stacking is followed by extensional reworking along the former thrust contacts or along new detachment surfaces. Our new ages suggest that exhumation of the uppermost units, which accompanied nappe stacking, probably started at 45 Ma and that the deepest units were almost completely exhumed at 33 Ma. This kinematics probably corresponds to syn-orogenic extension while the end of exhumation is clearly related to the extensional tectonics dated at 28.6 Ma along detachment structures.Our geochronological data reveal a very short lag time between accretional and extensional processes in this part of the Mediterranean Alpine orogenic belt. The direction of extension, when the units are restored to their initial position (i.e. before the opening of the Western Mediterranean basins and the bending of the arc) is NNE–SSW. Such a direction does not fit with the eastward slab-retreat model generally put forward to explain extension in the Western Mediterranean. In contrast, we provide evidence for roughly N–S middle Oligocene extension in the accretionary prism, not previously described in this part of the Mediterranean domain.  相似文献   

The Late Holocene to Pleistocene tephrostratigraphic record of Lake Ohrid (Albania)     

Benoît Caron  Roberto Sulpizio  Giovanni Zanchetta  Giuseppe Siani  Roberto Santacroce 《Comptes Rendus Geoscience》2010,342(6):453-466

We present in this work a tephrostratigraphic record from a sediment piston core (JO 2004) from Lake Ohrid. Five tephra layers were recognised, all from explosive eruptions of southern Italy volcanoes. A multidisciplinary study was carried out, including stratigraphy, AMS ¹⁴C chronology and geochemistry. The five tephra layers were correlated with terrestrial proximal counterparts and with both marine and lacustrine tephra layers already known in the central Mediterranean area. The oldest is from Pantelleria Island (P11, 131 ka BP). Other three tephra layers are from Campanian volcanoes: X6, Campanian Ignimbrite-Y5 and SMP1-Y3 (107, 39 and 31 ka BP respectively). The youngest tephra layer corresponds to the FL eruption from Etna Volcano (3.4 ka BP). In three cases these recognitions confirm previous findings in the Balkans, while two of them were for the first time recognised in the area, with a significant enlargement of the previous assessed dispersal areas.  相似文献   

A roadmap for a dedicated Earth Science Grid platform     

Roberto Cossu  Monique Petitdidier  Julian Linford  Vincent Badoux  Luigi Fusco  Benoit Gotab  Ladislav Hluchy  Giuditta Lecca  Fabrizio Murgia  Camiel Plevier  Philippe Renard  Horst Schwichtenberg  Wim Som de Cerff  Viet Tran  Gerald Vetois 《Earth Science Informatics》2010,3(3):135-148

Due to its intensive data processing and highly distributed organization, the multidisciplinary Earth Science applications community is uniquely positioned for the uptake and exploitation of Grid technologies. Currently Enabling Grids for E-sciencE, and other large Grid infrastructures are already deployed and capable of operational services. So far however, the adoption and exploitation of Grid technology throughout the Earth Science community has been slower than expected. The Dissemination and Exploitation of GRids in Earth sciencE project, proposed by the European Commission to assist and accelerate this process in a number of different ways, had between its main goals the creation of a roadmap towards Earth Science Grid platform. This paper presents the resulting roadmap.  相似文献   

Water quality and relationship between superficial and ground water in Rome (Aniene River basin,central Italy)   总被引：1，自引：1，他引：0  

Francesco La Vigna  Simone Ciadamidaro  Roberto Mazza  Laura Mancini 《Environmental Earth Sciences》2010,60(6):1267-1279

Chemical, physical, and biological features of streams and ground water of the North-Eastern area of Rome are jointly analyzed in order to assess the status of water resources. Ground water was investigated with classical survey methods (pH, temperature, and electric conductivity). Microbiological pollution, faunal composition, and stream surrounding area conditions of surface waters were studied, in order to quantify the residual value of these ecosystems from both a human and an environmental point of view. Results show a general impairment of the system and the comparison between superficial waters and shallow ground waters makes it possible to detect the presence of a connection between the two levels. This relationship occurs as an exchange from superficial waters (streams and rivers) to the shallow aquifers. Where superficial waters are contaminated, as in the Tor Sapienza stream, pollutants move to the shallow aquifers too, due to the decreased pressure of the over-exploited aquifer. Moreover, uncontrolled drilling activity, diffused in urban areas, makes it possible the connection between shallow and deep ground water. Notwithstanding this, the mixing between superficial and deep ground water system in Rome is not very widespread and, apparently, limited to restricted areas.  相似文献   

Changes in extremes and hydroclimatic regimes in the CREMA ensemble projections   总被引：2，自引：0，他引：2  

Filippo Giorgi  Erika Coppola  Francesca Raffaele  Gulilat Tefera Diro  Ramon Fuentes-Franco  Graziano Giuliani  Ashu Mamgain  Marta Pereira Llopart  Laura Mariotti  Csaba Torma 《Climatic change》2014,125(1):39-51

We analyze changes of four extreme hydroclimatic indices in the RCP8.5 projections of the Phase I CREMA experiment, which includes 21st century projections over 5 CORDEX domains (Africa, Central America, South America, South Asia, Mediterranean) with the ICTP regional model RegCM4 driven by three CMIP5 global models. The indices are: Heat Wave Day Index (HWD), Maximum Consecutive Dry Day index (CDD), fraction of precipitation above the 95th intensity percentile (R95) and Hydroclimatic Intensity index (HY-INT). Comparison with coarse (GPCP) and high (TRMM) resolution daily precipitation data for the present day conditions shows that the precipitation intensity distributions from the GCMs are close to the GPCP data, while the RegCM4 ones are closer to TRMM, illustrating the added value of the increased resolution of the regional model. All global and regional model simulations project predominant increases in HWD, CDD, R95 and HY-INT, implying a regime shift towards more intense, less frequent rain events and increasing risk of heat wave, drought and flood with global warming. However, the magnitudes of the changes are generally larger in the global than the regional models, likely because of the relatively low “climate sensitivity” of the RegCM4, especially when using the CLM land surface scheme. In addition, pronounced regional differences in the change signals are found. The data from these simulations are available for use in impact assessment studies.  相似文献