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31.
Intrinsic vulnerability assessment of Saturnia thermal aquifer by means of three parametric methods: SINTACS,GODS and COP 总被引：2，自引：1，他引：1
Enrico Guastaldi Luca Graziano Giovanni Liali Fabio Nunzio Antonio Brogna Alessio Barbagli 《Environmental Earth Sciences》2014,72(8):2861-2878
Three different parametric methods for the evaluation of intrinsic vulnerability to pollution have been applied in a hydrothermal carbonate aquifer located in central-northern Italy and the results obtained were compared with each other. The study area, large, approximately 152 km2, lies in an area of the northern Apennines. The investigated aquifer feeds the hot thermal springs of Saturnia. The vulnerability assessment methods used are: SINTACS, GODS and COP. The vulnerability maps obtained were first individually examined, and then they were compared with each other by means of spatial analysis. These maps show similar results for the estimation of the vulnerability just in some areas. SINTACS yields areas potentially vulnerable to pollution along the Albegna River and its major tributaries in the northern part of the study area. The GODS index map reflects the great importance that this method gives to the lithological characteristics of the unsaturated zone in the subdivision of areas with different vulnerability. GODS and COP methods agree in classifying low vulnerability in the most part of central-southern study area, where the aquifer is confined by the Pliocene clay deposits. Based on the conceptual model of groundwater flow developed for the aquifer under investigation, COP seems the most appropriate method among those applied in this work, in particular with regard to the assessment of the vulnerability of the recharge area of thermal groundwater. Located in the northern part of the study area, where karst carbonate formations of the Tuscan Nappe outcrop, this recharge area is classified by the COP method as highly vulnerable to pollution. 相似文献
32.
Caterina Gozzi Roberta Sauro Graziano Francesco Frondini Antonella Buccianti 《Environmental Earth Sciences》2018,77(16):579
Chemical reactions in aqueous geochemical systems are driven by nonequilibrium conditions, and their dynamics can be deduced through the distributional analysis (identification of probability laws) of complex compositional indices. In this perspective, compositional data analysis offers the possibility to investigate the behavior of the composition as a whole instead of isolated chemical species, with the awareness that multispecies systems are characterized by the simultaneous interactions among all their parts. We addressed this problem using D???1 isometric log-ratio coordinates describing the D compositional dataset of the river chemistry of the Alpine region (D number of variables), thus working in the \({{\mathbb{R}}^{D - 1}}\) statistical sample space. The D???1 coordinates were chosen using the decreasing variance criterion so that each one could provide information about different space–time properties for the investigated geochemical system. Coordinates dominated by heterogeneity appear to be able to capture regime shifts only on a long-time period and monitor processes on a very wide scale. On the other hand, coordinates characterized by lower variability present multimodality, thus capturing the presence of alternative states in the analyzed spatial domain also for the current time. Further developments are needed to determine the ranges of conditions for which variability and other statistics can be useful indicators of regime shifts on different time–space scales in geochemical systems. 相似文献
33.
Alessandro?Zini Sergio?GrausoEmail author Vladimiro?Verrubbi Luca?Falconi Gabriele?Leoni Claudio?Puglisi 《Landslides》2015,12(5):847-859
Debris flows represent dangerous occurrences in many parts of the world. Several disasters are documented due to this type of fast-moving landslides; therefore, natural-hazard assessment of debris flows is crucial for safety of life and property. To this aim, much current work is being directed toward developing geotechnical-hydraulic models for the evaluation of debris flow susceptibility. A common base for such current models is parameterization of background predisposing and triggering factors such as inherent characteristics of geo-materials, topography, landscape and vegetation cover, rainfall regime, human activities, etc. which influence the occurrence of these processes on slopes. The same factors are also taken into account in soil erosion prediction models. Consequently, it seems worth investigating the effectiveness of the soil erosion index as debris flows susceptibility indicator. To this aim, a logistic regression analysis was carried out between the erosion index assessed by means of the Revised Universal Soil Loss Equation (RUSLE) model and the inventory of debris flows that have occurred in an area in Sicily (Southern Italy). Model assumptions were verified and validated by means of a series of statistical tools. Different possible scenarios were also evaluated by considering hypothetical changes in soil erosion rate under different rain erosivity conditions. Notwithstanding the rough approximations in model data collection, the outcomes appear encouraging. 相似文献
34.
35.
Andrea Boattini Germano D’Abramo Giovanni B. Valsecchi Andrea Carusi Andrea Di Paola Fabrizio Bernardi Robert Jedicke Alan W. Harris Elisabetta Dotto Fiore De Luise Davide Perna Riccardo Leoni 《Earth, Moon, and Planets》2007,100(3-4):259-271
The Campo Imperatore Near Earth Object Survey (CINEOS) is an Italian survey dedicated to the search and follow-up of Near Earth Objects (NEOs). It is operated with the 90 cm f/3 Schmidt telescope at the Campo Imperatore of the Rome Astronomical Observatory (INAF-OAR) as a joint project with the Istituto di Astrofisica Spaziale and Fisica Cosmica (INAF-IASF) in Rome. Since the end of 2001 CINEOS has covered about 4,250 sq. deg to 20th magnitude in the course of about 160 nights. This effort led to the discovery of 7 Near Earth Asteroids (NEAs), 1 comet (167P/CINEOS; a member of the Centaur group) and a few other unusual objects including 2004 XH50 with a unique comet-like orbit. CINEOS has also contributed almost 2,200 preliminary designations and over 30,000 detections to the Minor Planet Center. About 20% of the survey effort was carried out at low solar elongations (LSE), although no object with an orbit interior (Inner Earth Objects, IEO class) or nearly interior to the Earth (Aten class) was found. The work at LSE was, however, very important to test survey strategies implemented with larger telescopes. We also provide the results of a CINEOS simulation on a reliable NEO population model based on the results of two larger scale surveys, Spacewatch and LINEAR. 相似文献
36.
P. Calosi S.P.S. Rastrick M. Graziano S.C. Thomas C. Baggini H.A. Carter J.M. Hall-Spencer M. Milazzo J.I. Spicer 《Marine pollution bulletin》2013
To reduce the negative effect of climate change on Biodiversity, the use of geological CO2 sequestration has been proposed; however leakage from underwater storages may represent a risk to marine life. As extracellular homeostasis is important in determining species’ ability to cope with elevated CO2, we investigated the acid–base and ion regulatory responses, as well as the density, of sea urchins living around CO2 vents at Vulcano, Italy. We conducted in situ transplantation and field-based laboratory exposures to different pCO2/pH regimes. Our results confirm that sea urchins have some ability to regulate their extracellular fluid under elevated pCO2. Furthermore, we show that even in closely-related taxa divergent physiological capabilities underlie differences in taxa distribution around the CO2 vent. It is concluded that species distribution under the sort of elevated CO2 conditions occurring with leakages from geological storages and future ocean acidification scenarios, may partly be determined by quite subtle physiological differentiation. 相似文献
37.
S. Businger T. M. Graziano M. L. Kaplan R. A. Rozumalski 《Meteorology and Atmospheric Physics》2005,88(1-2):65-90
Summary On 24–25 February 1989 a storm brought high winds and moderate to heavy snow to the U.S. East Coast. The storm is noteworthy for its rapid mesoscale development within a polar air mass at relatively low latitudes and for the difficulty experienced by operational NWP models and forecasters in predicting the storms impact. This paper investigates the mesoscale structure and evolution of the cold-air cyclone through analysis of enhanced data sets collected during the
xperiment on
apidly
ntensifying
yclones over the
tlantic (ERICA). Results are presented from numerical sensitivity studies of the impact of diabatic heating on storm structure and track using the Mesoscale Atmospheric Simulation System (MASS) model.The following conclusions are drawn from the research. Differential surface fluxes in the vicinity of the Gulf Stream led to the development of a well-defined baroclinic zone at low levels that extended parallel to the axis of the Gulf-Stream front. The baroclinic zone strengthened and assumed the characteristics of a shallow warm front as the cyclone matured. Enhanced cyclonic vorticity, moisture-flux convergence, clouds, and precipitation accompanied the front. Early in the event a series of shallow, thermally forced vortices of small wavelength (200km) formed along the baroclinic zone in the area of maximum surface-heat fluxes offshore of the Carolinas. Baroclinic instability associated with a vigorous short-wave trough aloft resulted in the outbreak of deep convection surrounding and rapid intensification of the northernmost vortex.Numerical sensitivity experiments were conducted to investigate the nonlinear response of the mass field to the convection. The results show that latent heating in deep convection surrounding the surface low produced a mesoscale height perturbation aloft. The subsequent acceleration of the flow aloft substantially increased the integrated mass divergence above the surface cyclone, leading to deepening on the scale observed. The observed track of the low followed the axis of the warm front, which in turn followed the axis of maximum SST gradient associated with the Gulf-Stream front. Accurate simulation of the storm track required a high-resolution, full-physics run that included high-resolution SST data in the initial condition and moisture nudging during the early hours of the simulation.Current affiliation: NWS Office of Climate, Water, and Weather Services, 1325 East-West Highway, Silver Spring, MD 20910.Current affiliation: NWS UCAR/COMET, Boulder, CO 80307-3000. 相似文献
38.
Heavy metal and arsenic distributions in sediments of the Elba-Argentario basin, southern Tuscany, Italy 总被引：2，自引：0，他引：2
Arsenic, chromium, cobalt, copper, lead, nickel, vanadium and zinc distributions in surficial and core sediments of the Elba-Argentario
marine basin (southern Tuscany, central-western Italy) are reported. Analysis of such distributions compared with grain size
and mineralogical data allowed the identification of areas showing trace element enrichments with respect to natural background.
These enrichments are moderate and essentially restricted to Pb and Zn; only As shows a widespread, though not high, positive
anomaly. This general pattern is in good agreement with the minor industrialization affecting the basin's watershed. An unexpected
anomaly, concerning Co, Pb, and As, as well as Fe and Ti, has been pointed out close to Montecristo Island. This has been
ascribed to illegal local dumping of chemical waste.
Received: 12 January 1996 / Accepted: 9 September 1996 相似文献
39.
Summary About 90 samples of mortars from historical buildings in Pisa have been analysed and compared with some samples of ancient mortars characterized by pozzolanic aggregates. Chemical (XRF), mineralogical (XRD) and petrographical (optical microscopy) data have been collected on bulk samples. An X-ray energy-dispersive system (EDS) attached to a SEM was used to determine the chemical compositions of binder, clots and pozzolanic grains (whenever present). The binder components which could not be directly assessed (CO2, H2O+) have been indirectly derived through a computation method.Data collected suggest that the main stock of analysed samples (i.e., mortars from Pisa monuments) contains two principal types of binder: the first type corresponds to a common carbonated lime; the second type is a hydraulic lime, where the carbonate component is associated with an important silicate fraction, which constitutes 13 to 89 wt% of the total binder (on average 47%). This hydraulic type had a widespread application in the construction of ancient monuments in Pisa; for example, it was constantly employed in the building of the famous Leaning Tower. This study shows that the silicate fraction of such hydraulic mortar, which is amorphous to X-ray diffraction, is made up by a hydrated calcium alumino-silicate having a very low Al2O3/SiO2 ratio (on average 0.125). On the basis of chemical and optical characteristics of hydraulic mortar binders from Pisa and the results of laboratory tests, as well as through comparison with the characteristics of ancient hydraulic mortars having pozzolanic aggregates, it is concluded that such mortars were prepared most likely by mixing slaked lime with a reactive, highly siliceous material such as a diatomaceous earth.
Über Bindemittel in antiken Mörteln
Zusammenfassung Etwa 90 Mörtelproben von historischen Gebäuden in Pisa wurden analysiert und mit Proben von antiken Mörteln, die durch pozzolanische Aggregate charakterisert sind, verglichen. Chemische (XRF), mineralogische (XRD) und petrographische (optische Mikroskopie) Daten wurden an den Gesamtproben ermittelt. Ein an ein SEM angeschlossenes energiedispersives System (EDS) wurde für die Bestimmung der chemischen Zusammensetzung des Bindemittels, der Mörtelklümpchen und der pozzolanischen Körner (sofern vorhanden) verwendet. Die Komponenten des Bindemittels, die nicht direkt gemessen werden konnten (CO2, H2O+) wurden indirekt durch ein Berechnungsverfahren ermittelt.Die gesammelten Daten belegen, dass die meisten untersuchten Proben (i.e. Mörtel von Monumenten aus Pisa) zwei Typen von Bindemittel enthalten: Der erste Typ entspricht einem gewöhnlichen karbonatisierten Kalk. Der zweite Typ ist ein hydraulischer Kalk, in dem die Karbonatkomponente mit einer mengenmäßig bedeutenden Silikatfraktion assoziiert ist, die 13–89 Gew.% des gesamten Bindemittels ausmachen kann (durchschnittlich 47%). Dieser zweite Typ wurde häufig beim Bau alter Monumente in Pisa verwendet, z.B. wurde er ständig beim Bau des Schiefen Turms herangezogen. Diese Studie zeigt, dass die Silikatfraktion dieses hydraulischen Mörtels, die röntgenamorph ist, aus einem hydratisierten Aluminosilikat mit einem niedrigen Al2O3/SiO2 Verhältnis (im Durchschnitt 0.125) besteht.Auf Basis der chemischen und optischen Charakteristika des hydraulischen Mörtel, die pozzolanische Aggregate führen, schließen wir, dass diese Mörtel höchstwahrschein lich durch Mischung von Löschkalk mit sehr reaktivem, silikatischen Material, wie etwa Diatomeenerde hergestellt wurden.相似文献
40.
Patti Graziano Grassi Sabrina Morreale Gabriele Corrao Mauro Imposa Sebastiano 《Natural Hazards》2021,108(3):2467-2492
Natural Hazards - The occurrence of strong and abrupt rainfall, together with a wrong land use planning and an uncontrolled urban development, can constitute a risk for infrastructure and... 相似文献