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91.
This paper explores sovereign risk preferences against direct and indirect natural disasters losses in industrialized countries. Using Australia as a case study, the analysis compares expected disaster losses and government capacity to finance losses. Utilizing a national disaster loss dataset, extreme value theory is applied to estimate an all-hazard annual loss distribution. Unusually but critically, the dataset includes direct as well as indirect losses, allowing for the analysis to consider the oft-ignored issue of indirect losses. Expected annual losses (direct, and direct plus indirect) are overlaid with a risk-layer approach, to distinguish low, medium and extreme loss events. Each risk layer is compared to available fiscal resources for financing losses, grounded in the political reality of Australian disaster financing. When considering direct losses only, we find support for a risk-neutral preference on the part of the Australian government for low and medium loss levels, and a risk-averse preference in regard to extreme losses. When indirect losses are also estimated, we find that even medium loss levels are expected to overwhelm available fiscal resources, thereby violating the available resources assumption underlying arguments for sovereign risk neutrality. Our analysis provides empirical support for the assertion that indirect losses are a major, under-recognised concern for industrialized countries. A risk-averse preference in regard to medium and extreme loss events recommends enhanced investment in both corrective and prospective risk reduction in relation to these risks level, in particular to reduce indirect losses.  相似文献   
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Journal of Material Cycles and Waste Management - The substitution of standard clays to residues, in this case copper smelter slag and fly ashes coming from the incineration process of MSW in...  相似文献   
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The paper presents results of natural radioactivity levels in the atmosphere obtained for a 5 years period (1994-1999) at the Bucharest Environmental Radioactivity Surveillance Station (BERSS). The variability of radon and thoron progeny activity concentrations is analysed in relation to the local dynamics of the meteorological parameters (wind speed, air temperature, air pressure, cloud cover, relative humidity). The radon and thoron progeny concentrations display a daily and seasonal variation, with the highest values in the early morning and the lowest values in the afternoon. The outdoor radon progeny concentrations show maximum values in autumn and minimum values in spring-summer. The outdoor thoron progeny concentrations display maximum values in autumn and minimum values in winter. Significant statistical correlations with the meteorological parameters were obtained. The study on the temporal variability of natural atmospheric radioactivity near Bucharest is a starting point for further assessment of the radiological consequences resulting from human activities.  相似文献   
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Vergés A  Paul NA  Steinberg PD 《Ecology》2008,89(5):1334-1343
Intraspecific variation in resistance to herbivory among genders and life-history phases of primary producers can significantly alter the ecological and evolutionary consequences of plant-herbivore interactions. Seaweeds (macroalgae) with complex life histories have multiple distinct phases with associated variation in traits that can potentially lead to differences in resistance to consumers and provide a unique system in which to simultaneously test the effects of sex and life-history stage on herbivory. We tested the susceptibility to grazing of the three life-history stages and separate sexes of the chemically defended red alga Asparagopsis armata against the sea hare Aplysia parvula, and we related this to the plant quality traits of different stages and genders. Differences in nutrient content and halogenated secondary metabolites between life-history phases were highly sex dependent. Male gametophytes had a low concentration of secondary metabolites and the highest nutrient content. The highest secondary metabolite content was found within the female gametophyte, in the wall of the reproductive structures (cystocarps) that contain the microscopic carposporophyte phase. Feeding choices by A. parvula were consistent with differences in algal quality and defense and resulted in the haploid male gametophytes being the most preferred food type. The diploid carposporophyte found inside the chemically rich cystocarps was the least consumed life-history stage. Selective herbivory of male gametophytes by A. parvula is consistent with an observed shift in gametophyte sex ratio in the field from unity at the beginning of the reproductive season to female bias at the end. The variation in susceptibility to herbivory found between sex and life-history stages of A. armata represents the first example of sex-biased consumption in seaweeds and may contribute to the maintenance of complex life histories such as those found in red algae.  相似文献   
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The objective of this work is to analyze and interpret the components or hydrogeological, physical, and chemical variables of the San Diego aquifer to describe it and explain its influence on the sustainable use of groundwater for the providing of this locality. The San Diego municipality covers most of the area of the aquifer and is an area of high urban development that currently needs the contribution of groundwater due to the deficit presented by the main supply from the Central Regional System. Said aquifer is a set of geological strata located within the limits of the San Diego River basin, in the state of Carabobo, which are capable of storing groundwater and transmitting it. Data on lithology, porosity, and pumping level were investigated, which allows calculating an estimate of the volume of water available in the aquifer. Regarding the quality of the water, the data on hardness, chlorides, sulfates, nitrates, conductivity, calcium, magnesium, and pH, show that the water towards the center and north of the aquifer is of good quality, being able to classify it as type 1A, while toward the southern end—this is of lower quality, where the mineral parameters are higher, which is related to the probable intrusion of brackish water from Lake Valencia. It is concluded by establishing that the volume of groundwater, its availability, extraction feasibility, and its quality, make it suitable for urban supply and that said extraction is sustainable. But a better-integrated type of management must be designed, considering the contribution of the Regional System of the Center and the adequacy of the distribution networks.  相似文献   
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