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A life cycle assessment (LCA) of a domestic cooker hood was conducted. Cradle-to-grave analysis was performed using the GaBi software with Eco-Indicator 99 (Egalitarian Approach). The most polluting phases were “manufacturing” and “use”, the environmental impact being affected especially by production materials and the electricity consumed during the product’s lifespan. The study also highlighted that the hood’s environmental impact is closely related to the local power grid mix. This aspect was further analyzed by entering the data for operating it both in Italy and in France. Finally, the improvements obtained by replacing the single-phase electrical motor with an inverter-driven three-phase induction one and the halogen lamps with Light Emitting Diode (LED) lamps were assessed with the LCA. These changes entail an improvement of the environmental impact of 36% in Italy and of 24% in France.  相似文献   
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The sustainability of large dams has been questioned on several grounds. One aspect that has been less explored is that the development of dams and reservoirs often enables agricultural expansion and urban growth, which in turn increase water consumption. As such, dam development influences, while being influenced by, the spatial and temporal distribution of both supply and demand of water resources. In this paper, we explore the interplay between large dams, patterns of population growth and agricultural expansion in the United States over the past two centuries. Based on a large-scale analysis of spatial and temporal trends, we identify three distinct phases, in which different processes dominated the interplay. Then, we focus on agricultural water use in the Southwest region (Arizona, California and Nevada) and explore chicken-and-egg dynamics where water supply partly meets and partly fuels water demand. Lastly, we show that the legacy of dams in the United States consists of a lock-in condition characterized by high levels of water consumption, especially in the Southwest, which leads to severe water crises and groundwater overexploitation when droughts occur.  相似文献   
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Zooplankton samples, collected in autumn 1996 from two stations in the Gulf of Rapallo, Ligurian Sea (Rapallo Harbour and Prelo Bay, which is a more open site with lower human impacts) were analysed. at both stations, the community was dominated by copepods (mainly juveniles and adults of different species of Acartia and Oithona) and meroplankton (mainly polychaete larvae). Total zooplankton abundance in the harbour waters was significantly higher than in the nearby bay. the occurrence of Acartia grani in Rapallo Harbour and Pteriacartia josephinae in Prelo Bay is noteworthy, as they are reported for the first time in the Ligurian Sea, and A. grani has not previously been recorded to the Italian coastline. A three-day benthic chamber experiment aimed to quantify nutrient fluxes between the sediment and water column was performed in the Rapallo Harbour: the profound effects of confinement on the composition and abundance of zooplankton within the incubation chamber are discussed.  相似文献   
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Data on the indicators of environmental impact of tire debris, originated from the tire abrasion on roads, are extremely scarce, while it is well known that tires may produce deleterious effects. Tire debris contains significant quantities of zinc (Zn) which may be released by tire rubber. We have used tire particles (TD) produced in laboratory from new rubber. Two sets of experiments were set up to obtain eluates. One set used 50 and 100 g/L TD to produce eluates at pH 3-7. The Zn quantity was measured with a Inductively Coupled Plasma-Atomic Emission Spectrometry. The eluates at 1%,10%,50%,100% concentrations in culture media were tested on Raphidocelis subcapitata, Daphnia magna and Xenopus laevis embryos (FETAX test). The other set of experiments was performed putting 250 mg/L TD in a column with glass beads to control particle dispersion during the elution process. We demonstrate that factors such as pH, size and particles aggregation deeply influence the elution process, that the amount of Zn leached from particles is related to their aggregation rather than their quantity. These results, even though do not reflect the real environmental toxicity of the leachates, can be successfully used for comparative purposes allowing an initial assessment of the potential effect of tire derived particles.  相似文献   
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Polychlorinated biphenyls (PCBs), dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and hexaclorobenzene (HCB) were determined in three sediment cores of the Venice Lagoon: I1, from the San Giuliano Canal that is likely the main source of pollutants for the study area; E, representing the lagoon sediment of the zone of Campalto; and M3, typical of a salt marsh environment and mostly subject to atmospheric inputs. Maximum concentrations were found in core I1: 25-1858 ngI-TE kg(-1) (PCDD/Fs), 1.7-13 microg kg(-1) (HCB), and 107-717 microg kg(-1) (PCBs) are surficial and peak values, respectively. The lagoon sediment (E), is much less contaminated: 24-47 ngI-TE kg(-1) for PCDD/Fs, 2.3-3.6 microg kg(-1) for HCB, and 56-203 microg kg(-1) for PCBs, whereas M3 shows the lowest values: 1.6-6.0 ngI-TE kg(-1) for PCDD/Fs, 0.3-0.6 microg kg(-1) for HCB, and 7.1-39 microg kg(-1) for PCBs. In any case, the recent trend is toward a decrease of pollutant concentration. The chronology of cores E and M3 is based on both 210Pb and 137Cs activity-depth profiles. The maximum concentrations of PCDD/Fs, HCB, and PCBs correspond to the years 1949, 1980, and 1968, respectively. The homologue profiles of PCDD/Fs confirm that I1 has been subject to an industrial source while the other sites also recorded significant contributions, changing over time, of octachlorinated dioxin from combustion. A comparison of the pollutant inventories, all normalised to 210Pb inventories, suggests that the atmospheric contribution to the contamination of the area of Campalto is low: the upper limits range from 6% (PCDD/Fs) to 17% (HCB).  相似文献   
19.
The use of mosses as environmental metal pollution indicators   总被引:13,自引:0,他引:13  
The possibility of using mosses as environmental indicators of metal pollution has been investigated. Mosses of the species Bryum argenteum were collected from different parts of Piedmont (Italy), ranging from highly polluted areas to nearly uncontaminated mountain areas. Periodical samplings were planned in every site on a monthly base, in order to check variations of metal uptake throughout one year; correlations with pluviometric and thermal patterns were investigated for all sampling stations. On every moss sample 20 elements, ranging from major (K, P, Al, Ca, Fe and Mg) to minor (Mn, Na, Ti and Zn) and trace (As, Ba, Cd, Co, Cr, Cu, Li, Ni, Pb and Sr), were quantitatively determined by inductively coupled plasma-atomic emission spectrometry or graphite furnace-atomic absorption spectrometry, depending on the needed sensitivity. Statistical analyses, carried out with principal component analysis and cluster analysis methods, revealed that a good correlation exists between metal content in mosses and pollution degree in the areas sampled.  相似文献   
20.
Prey that are capable of continuously learning the identity of new predators whilst adjusting the intensity of their responses to match their level of risk, are often at a substantive advantage. Learning about predators can occur through direct experience or through social learning from experienced individuals. Social learning provides individuals with an effective means of acquiring information while reducing the costs associated with direct learning. Under a natural setting, social learning is likely to occur between more than two individuals. As such, investigating the effect that group size has on the ability of individuals to acquire information is vital to understanding social learning dynamics. Given the characteristics of coral reefs and the biology of coral reef fishes, these habitats are an ideal medium to test whether group size affects the transmission of information. Using newly settled damselfish (Pomacentrus amboinensis), we examined whether the number of observers present influences transmission of information. We showed that: (1) predator recognition is socially transmitted from predator-experienced to predator-naïve individuals regardless of group size, and that (2) the level of response displayed by the observer does not differ following learning in different sized groups. Our study highlights that information on predator identities is able to be passed onto group members quickly without a dilution of information content.  相似文献   
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