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241.
Assessing the environmental impact due to consumption of goods and services is a pivotal step towards achieving the sustainable development goal related to responsible production and consumption (i.e. SDG 12). Household appliances plays a crucial role and should be assessed in a systemic manner, namely considering all life cycle stages, technological efficiency, and affluence aspects. The present study assess the impact of such household appliances used in Europe, and tests scenarios of potential impact reduction at various scales. Life cycle assessment is applied to 14 different household appliances (ranging from dishwashers to television devices) selected to build a set of representative products, based on their economic value and diffusion in households in Europe. Related impacts are calculated with the Environmental Footprint method for calculating a Consumer Footprint “appliances” for the baseline year 2010. A number of scenarios encompassing eco-solutions on a technical level, changes in consumption pattern, behavioral changes, as well as the combination of all these aspects are run to estimate the Consumer Footprint related to household appliances for the year 2030, compared against this baseline scenario. The baseline Consumer Footprint is confirming the importance of the use phase in leading the impacts in almost all impact categories. Testing different scenarios concludes that there is a reduction of the impact for most of the categories (with up to 67% for the ozone depletion potential, and still around 35% for the global warming potential), while two of the here examined impact categories (i.e. land-use and mineral resource depletion) show an overall potential that is even negative – i.e. the results of all scenarios are higher than the ones of the 2010 baseline scenario. The increase in purchase and use of such appliances may offset energy efficiency benefits in some of the examined categories. Hence, the assessment of sustainability of appliances consumption should always include several scales, from the efficiency of the products (micro scale), to the improvement of the energy mix (meso scale), up to accounting for socio-economic drivers and patterns of consumption affecting the overall appliances stock (macro scale).  相似文献   
242.
The climatology and interannual variability of winter phytoplankton was analyzed at the Long Term Ecological Research Station MareChiara (LTER-MC, Gulf of Naples, Mediterranean Sea) using data collected from 1985 to 2006. Background winter chlorophyll values (0.2–0.5 μg chl a dm−3) were associated with the dominance of flagellates, dinoflagellates, and coccolithophores. Winter biomass increases (<5.47 μg chl a dm−3) were often recorded until 2000, generally in association with low-salinity surface waters (37.3–37.9). These blooms were most often caused by colonial diatoms such as Chaetoceros spp., Thalassiosira spp., and Leptocylindrus danicus. In recent years, we observed more modest and sporadic winter biomass increases, mainly caused by small flagellates and small non-colonial diatoms. The resulting negative chl a trend over the time series was associated with positive surface salinity and negative nutrient trends. Physical and meteorological conditions apparently exert a strict control on winter blooms, hence significant changes in winter productivity can be foreseen under different climatic scenarios.  相似文献   
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Probabilistic landslide hazard assessment at the basin scale   总被引:32,自引:9,他引:32  
We propose a probabilistic model to determine landslide hazard at the basin scale. The model predicts where landslides will occur, how frequently they will occur, and how large they will be. We test the model in the Staffora River basin, in the northern Apennines, Italy. For the study area, we prepare a multi-temporal inventory map through the interpretation of multiple sets of aerial photographs taken between 1955 and 1999. We partition the basin into 2243 geo-morpho-hydrological units, and obtain the probability of spatial occurrence of landslides by discriminant analysis of thematic variables, including morphological, lithological, structural and land use. For each mapping unit, we obtain the landslide recurrence by dividing the total number of landslide events inventoried in the unit by the time span of the investigated period. Assuming that landslide recurrence will remain the same in the future, and adopting a Poisson probability model, we determine the exceedance probability of having one or more landslides in each mapping unit, for different periods. We obtain the probability of landslide size by analysing the frequency–area statistics of landslides, obtained from the multi-temporal inventory map. Assuming independence, we obtain a quantitative estimate of landslide hazard for each mapping unit as the joint probability of landslide size, of landslide temporal occurrence and of landslide spatial occurrence.  相似文献   
245.
In situ U–Pb dating of zircons from five samples of Calabrian augen gneisses shows that their protoliths are Latest Precambrian to Early Cambrian in age (562 ± 15, 547 ± 7, 540 ± 4, 539 ± 16 and 526 ± 10 Ma), and contain Archaean (3.1 Ga), Palaeoproterozoic (1.7–2.4 Ga) and Neoproterozoic (0.6–0.9 Ga) inheritance. Geochemical signature of augen gneisses is typical of high-K calc-alkaline post-collisional magmatism. Their Sr–Nd isotopic compositions [0.7093 < (87Sr/86Sr)i < 0.7139; −3.2 < ɛNd(t) < −5.4; 1.5 < T DM < 1.7 Ga] indicate the involvement of a crustal component in significant proportions. The Calabrian augen gneisses have, therefore, to be distinguished from the orthogneisses of Sardinia and northern Algeria, and from the porphyroids of Sicily, which are Middle Ordovician. By contrast, the Calabrian augen gneisses show a close similarity to the Pan-African post-collisional granitoids of the northern edge of the West African craton (e.g. the Moroccan Anti-Atlas). This suggests a peri-Gondwana origin and corroborates previous palaeogeodynamic reconstructions attributing the Alboran microplate to the northern margin of the West African craton.  相似文献   
246.
Spectral ground motion (1 to 15 Hz) as a function of distance is modeled for events spanning 3.0 <Mw ≤ 7.0 in Switzerland. The parameters required to simulate ground motion with a stochastic approach are inverted from 2958 horizontal and vertical component waveforms of small to moderate size events (2.0 ≤ M{L} ≤ 5.2) in the distance range 10 to 300 km recorded on hard rock sites. Using a Monte Carlo simulation, we establish a significantly different amplification of about a factor of 1.9 between the Alpine Foreland and the Alps. To assess the trade-off between the free parameters of our stochastic model and their influence on the predictive ground motion relationship, we perform a grid search over the five-dimensional solution space. The uncertainties are separated into epistemic and aleatory parts; the main epistemic uncertainty is attributed to the lack of data forM > 5. To constrain the viable models at large magnitudes, results from worldwide scaling studies are evaluated in light of the Swiss data. The model that explains best the low observed stress drops at small magnitudes (Δσ ≅ 3 bar) yet matches observed intensities of historical earthquakes assumes a stress drop increasing with moment asM00.25. For three sites in Switzerland we evaluate the sensitivity of the epistemic uncertainty by computing probabilistic hazard curves. Our model offers the most comprehensive and detailed study of spectral ground motion for Switzerland to date.  相似文献   
247.
248.
We present the results of a detailed spectral analysis of optically faint hard X-ray sources in the Chandra deep fields selected on the basis of their high X-ray to optical flux ratio (X/O). The stacked spectra of high X/O sources in both Chandra deep fields, fitted with a single power-law model, are much harder than the spectrum of the X-ray background (XRB). The average slope is also insensitive to the 2–8 keV flux, being approximately constant around Γ≃ 1 over more than two decades, strongly indicating that high X/O sources represent the most obscured component of the XRB. For about half of the sample, a redshift estimate (in most of the cases a photometric redshift) is available from the literature. Individual fits of a few of the brightest objects and of stacked spectra in different redshift bins imply column densities in the range  1022–1023.5 cm−2  . A trend of increasing absorption towards higher redshifts is suggested.  相似文献   
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250.
In the Central Apennines (Italy) three major domains can be recognized: the Umbria and Marche pelagic domains and the Lazio-Abruzzi carbonate platform. Their Mesozoic-Tertiary sequences are separated by major low-angle thrust systems, which superpose the Umbria domain onto both the Marche and Lazio-Abruzzi domains, the Lazio-Abruzzi platform onto the Marche sequence, and all of them onto the Apulia foreland.From Lias to Cretaceous times the Lazio-Abruzzi platform was a fault-controlled uplifted domain separating the Umbria basin to the west from the Marche basin to the east, but closed to the north. The Umbria and Marche basins evolved distinctly with the onset of the terrigenous infilling, beginning with the Serravallian-Tortonian «Marnoso-Arenacea» Formation in the inner Umbria basin and with the Messinian-Early Pliocene Laga Flysch in the outer Marche basin. From Tortonian till Early Pliocene times there was a progressive deformation of the Umbria sequence, with its emplacement onto the Lazio-Abruzzi platform, and the deformation of the Lazio-Abruzzi and Marche zones. In Early-Middle Pliocene times, both the Umbria and Lazio-Abruzzi domains were emplaced onto the previously deformed Marche domain, with passive transport of that portion of Umbria stacked on top of the Lazio-Abruzzi platform. The final stages in Middle-Late Pliocene times caused further motion of the Lazio-Abruzzi platform along the arc-shaped Gran Sasso-Morrone thrust front. Folding and thrusting persisted in the outermost zones till Early Pleistocene times.This reconstruction means that in this area the model of a regularly forward migrating fold-thrust belt is not applicable. It also suggests a large northward displacement of the Lazio-Abruzzi platform, whose differential advancement may be dynamically related to a left-lateral discontinuity to the west and a right-lateral discontinuity to the east. According to our interpretation, the left-lateral discontinuity is not coincident with the «Ancona-Anzio» line of the Italian literature, but rather is buried underneath the Umbria stacked sequences.
Zusammenfassung Der Zentralappennin (Italien) besteht aus drei Hauptbereichen: die pelagialen Gebiete Umbriens und der Marche sowie die Karbon-Platte Latiums und der Abruzzen. Die Formationsgruppen des Mesozoikum-Tertiär dieser drei Gebiete werden durch große Überschiebungsbahnen getrennt, welche die umbrische Zone auf die Zone der Marche sowie Latiums und der Abruzzen schieben, die Zone Latiums und der Abruzzen ihrerseits auf die Formation der Marche und alle zusammen auf das Vorland Apuliens.Die ursprüngliche paleogeographische Struktur der drei Gebiete läßt darauf schließen, daß die Latium-Abruzzen-Platte vom Lias bis zur Kreidezeit eine aktive, erhobene Zone darstellt, die das Umbrische Becken im Westen vom Becken der Marche im Osten trennt, wobei sich die Platte nach Norden hin schließt, was ein Ineinandergreifen der beiden pelagialen Gebiete mit sich bringt. Beide Becken weisen eine getrennte Evolution auf, mit dem Beginn einer terrigenen Zufuhr, bestehend aus der Marnoso-Arenacea-Formation des Serravall-Tortons im Inneren des Umbrischen Beckens und mit dem Laga Flysch des Messin und Unter-Pliozän im äußeren Umbrischen Becken. Vom Torton bis zum Unteren Pliozän hat eine progressive Deformation der Umbrischen Sequenz stattgefunden, die auf dem Gebiete Latiums und der Abruzzen abgelagert wurde, was wiederum zur Deformation in der Zone Latiums und der Abruzzen sowie der Marche führte. Im unteren Mittel-Pliozän wurden sowohl die Formationen Umbriens als auch die der Zonen von Latium und der Abruzzen auf die schon deformierte Formationsgruppe der Marche aufgeschoben, mit nachfolgend passivem Transport des schon auf der Latium-Abruzzen-Platte aufgelagerten Teils der Umbrischen Formation. Die letzten Ereignisse im mittleren Ober-Pliozän führten zu einem weiteren Vorschub der Latium-Abruzzen-Platte längs der bogenförmigen Verwerfungsfront Gran Sasso-Morrone, sowie zu nachfolgenden Falten und Verwerfungen in den äußersten Gebieten bis zum unteren Pleistozän.Diese Rekonstruktion bedeutet vor allen Dingen, daß in diesem Gebiet das Modell einer regelmäßig voranschreitenden Überschiebungsfront nicht anwendbar ist. Sie deutet ferner auf eine große, nordwärts gerichtete Verschiebung der Latium-Abruzzen-Platte hin, deren differenzierter Vorschub dynamisch in Bezug zu einer links-lateralen Verschiebung nach Westen und einer rechts-lateralen Verschiebung nach Osten zu bringen ist. Gemäß unserer Auslegung stimmt die links-laterale Verschiebung nicht mit der «Ancona-Anzio» Linie der einschlägigen italienischen Fachliteratur überein, sondern ist eher unter den überlagernden Sequenzen Umbriens zu suchen.

Résumé On peut distinguer trois domaines dans la partie centrale des Apennins (Italie): le domaine pélagique des Marches, celui de l'Ombrie et la plate-forme carbonatée du Latium-Abruzzes. Les séries stratigraphiques mésozoïques-tertiaires de ces trois domaines sont séparées par d'importants systèmes de chevauchement qui ont provoqué la superposition du domaine ombrien sur ceux des Marches et du Latium-Abruzzes, la superposition de la plate-forme du Latium-Abruzzes sur la série des Marches, et enfin la superposition de toute la chaîne sur l'avantpays de l'Apulie.Du Lias au Crétacé, la plate-forme du Latium-Abruzzes constituait un domaine soulevé par des failles actives; ce domaine séparait le bassin de l'Ombrie à l'ouest du bassin des Marches à l'est et était limité au nord, permettant ainsi la communication des deux régions pélagiques. Ces deux bassins ont présenté une évolution distincte débutant par un remplissage terrigène; celui-ci est représenté, dans le bassin ombrien plus interne par la Formation Marnoso-Arénacéa (Serravalien-Tortonien), et dans le bassin externe des Marches par la formation du Flysch de la Laga (Messinien-Pliocène inférieur). A partir du Tortonien jusqu'au début du Pliocène, la série ombrienne a subi une déformation progressive, et à été charriée sur le domaine du Latium-Abruzzes, provoquant la déformation de ce dernier, ainsi que du domaine des Marches. Au cours du Pliocène inférieur et moyen, les domaines de l'ombrie et du Latium-Abruzzes ont été charriés sur la série des Marches ainsi déformée, entraînant de ce fait le transport passif de la portion de la séquence ombrienne préalablement charriée sur la plate-forme du Latium-Abruzzes. Plus tard, des mouvements méso- à tardi-pliocènes ont provoqué un dernier charriage de la plate-forme du Latium-Abruzzes le long de l'arc de chevauchement Gran Sasso-Morrone; enfin, les plissements et les charriages ont persisté dans les zones les plus externes jusqu'au Pléistocène inférieur.Cette reconstitution signifie que le modèle d'une chaîne plissée et charriée se déplaçant régulièrement vers l'avant-pays ne peut pas être appliqué à cette région. Elle indique également un vaste déplacement vers le Nord de la plate-forme du Latium-Abruzzes, transport qui peut être dynamiquement mis en relation avec un décrochement sénestre à l'ouest et un décrochement dextre à l'est. Selon notre interprétation, le décrochement sénestre ne coïncide pas avec la ligne «Ancona-Anzio» de la littérature italienne, mais est enterré sous l'édifice charrié de l'Ombrie.

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