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331.
332.
Climate change severely impacts on the natural and socio-economic systems of the Pacific Islands. Samoa, a small insular state of the region, is characterized by widespread awareness of climate change reflected by its leading international role. This also makes Samoa a potentially exemplary reference for the Pacific Islands. Against this backdrop, the overall aim of this article is to investigate the notion of social vulnerability and measure its dimensions in Samoa through a specific index: the Samoa Social Vulnerability Index (SSVI). The SSVI may yield better understanding of the characteristics and dynamics of social vulnerability, as well as information for fostering adaptation strategies in Samoa and in the Pacific Islands. In particular, the article first outlines the major vulnerabilities to climate change in Samoa and then analyses the composite notion of social vulnerability. On this basis, the article methodologically specifies, designs and constructs the SSVI. Afterwards, it uses such index for measuring the dimensions of social vulnerability in Samoa’s districts. Finally, some considerations are made concerning the policy relevance of the SSVI and its potential regional role.  相似文献   
333.
Sustainable provision of seafood from wild-capture fisheries and mariculture is a fundamental component of healthy marine ecosystems and a major component of the Ocean Health Index. Here we critically review the food provision model of the Ocean Health Index, and explore the implications of knowledge gaps, scale of analysis, choice of reference points, measures of sustainability, and quality of input data. Global patterns for fisheries are positively related to human development and latitude, whereas patterns for mariculture are most closely associated with economic importance of seafood. Sensitivity analyses show that scores are robust to several model assumptions, but highly sensitive to choice of reference points and, for fisheries, extent of time series available to estimate landings. We show how results for sustainable seafood may be interpreted and used, and we evaluate which modifications show the greatest potential for improvements.  相似文献   
334.
Human biomonitoring (HBM), defined as the measurement of concentrations of chemicals or of their metabolites in human biological matrices, is considered the method of choice for determining internal exposures in individuals. HBM is part of environmental exposure surveillance systems in several countries. In 2007, the Ministry of Agriculture, Food and Environment promoted BIOAMBIENT.ES project, a national-level HBM study on environmental pollutants carried out in Spain to estimate levels of heavy metals, persistent organic pollutants, and other substances on the Spanish active workforce. BIOAMBIENT.ES is a nationwide cross-sectional study, with a stratified cluster sampling designed to cover all geographical areas, sex and occupational sectors, and aimed to obtain a representative sample of the Spanish workforce. Participants were recruited among people residing in Spain for 5 years or more, which underwent their annual occupational medical check-up in the health facilities of the Societies for Prevention of IBERMUTUAMUR, MUTUALIA, MC-PREVENCIÓN, MUGATRA, UNIMAT PREVENCIÓN, and PREVIMAC (March 2009–July 2010). A total of 1,892 subjects fulfilled the criteria for inclusion, donated biological samples (1,880 blood, 1,770 urine, and 577 hair) and completed a short self-administrated epidemiological questionnaire on environmental and lifestyle-related exposures. Additionally, clinical information from participant’s health exams was obtained. This project will provide a first overview of the body burden of selected pollutants in a representative sample of the Spanish-occupied population. This information will be useful to establish reference values of the studied population and, eventually, to evaluate temporal trends and the effectiveness of environmental and health policies.  相似文献   
335.
Enchytraeus crypticus as model species in soil ecotoxicology   总被引:1,自引:0,他引:1  
Enchytraeids are ecologically relevant soil organisms, due to their activity in decomposition and bioturbation in many soil types worldwide. The enchytraeid reproduction test (ERT) guidelines ISO 16387 and OECD 220 are exclusive to the genus Enchytraeus and recommend using the species E. albidus with a 6-week test period. The suggested alternative, E. crypticus has a shorter generation time which may enable the ERT to be twice as fast. To confirm the suitability of a 3-week test period for E. crypticus, the toxicity of five chemicals, with distinct properties and modes of action, was assessed in LUFA 2.2 soil. In all controls the validity criteria were met, as survival of E. crypticus was above 92% and more than 772 juveniles were produced. The good performance supports its appropriateness as model species. Reproduction was more sensitive than survival, with only cadmium and 3,5-dichloroaniline causing significant lethal effects in the tested concentration ranges. The effect concentration causing 50% reduction in the number of juveniles (EC50) was 35 mg kg−1 for cadmium, <1.0 mg kg−1 for carbendazim, 145 mg kg−1 for phenanthrene, 275 mg kg−1 for pentachloroaniline and 102 mg kg−1 for 3,5-dichloroaniline. To evaluate the sensitivity of E. crypticus, the present results were compared to literature data for E. albidus. In conclusion, E. crypticus is a suitable model species in soil ecotoxicology, with advantages such as good control performance and speed, leading to a reliable and faster ERT.  相似文献   
336.
Observation-based methods are useful tools to explore the sensitivity of ozone concentrations to precursor controls. With the aim of assessing the ozone precursor sensitivity in two locations: Paterna (suburban) and Villar del Arzobispo (rural) of the Turia river basin in the east of Spain, the photochemical indicator O3/NOy and the Extent-of-Reaction (EOR) parameter have been calculated from field measurements. In Paterna, the O3/NOy ratio varied from 0 to 13 with an average value of 5.1 (SD 3.2), whereas the averaged value for the EOR was 0.43 (SD 0.14). In Villar del Arzobispo, the O3/NOy ratio changed from 5 to 30 with a mean value of 13.6 (SD 4.7) and the EOR gave an averaged value of 0.72 (SD 0.11). The results show two different patterns of ozone production as a function of the location. The suburban area shows a VOC-sensitive regime whereas the rural one shows a transition regime close to NOx-sensitive conditions. No seasonal differences in these regimes are observed along the monitoring campaigns. Finally, an analysis of the influence of the measurement quality of NOy, NOx and O3 on the uncertainty of the O3/NOy ratio and the EOR was performed showing that the uncertainty of O3/NOy is not dependent on either its value or the individual values of O3 and NOy but just on the quality of O3 and NOy measurements. The maximum uncertainty is 26% as long as the combined uncertainties of O3 and NOy remain below the 7.5%. The case of the EOR is different and its uncertainty depends on both the value of the EOR parameter and the individual concentration values of NOy and NOx. The uncertainty of the EOR estimation can be very high (>200%) if the combined uncertainties of both NOy and NOx are high (>7.5%), or especially, if u(NOy) and u(NOx) differ considerably from each other (>3.5%).  相似文献   
337.
The aim of this study was to measure, 6 years after regular operations, the concentrations of a number of organic substances in blood and urine of 19 workers employed at a hazardous waste incinerator (HWI) in Spain, and to establish the temporal variation with respect to baseline data and previously performed surveys. This facility was the first, and so far the only HWI in that country. The levels of hexachlorobenzene (HCB), polychlorinated biphenyls (PCB 28, 52, 101, 138, 153 and 180) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were analyzed in six composite plasma samples, while concentrations of di-, tri, and pentachlorophenols, as well those of 1-hydroxypyrene were measured in the urine of these workers. The current mean PCDD/F concentration, 10.4 ng I-TEQ/kg lipid, was significantly lower than that found in the baseline survey, 26.7 ng I-TEQ/kg lipid and similar to that found in the previous (2004) study (7.7 ng I-TEQ/kg lipid). PCDD/F levels in plasma were similar or even lower than those recently reported for various non-exposed populations. For the remaining analyzed substances in plasma and urine, there was not any significant increase in comparison with the levels found in the baseline survey. On the other hand, no marked differences between the concentrations of organic substances in plasma or urine were found according to the respective workplace (plant, laboratory and administration). The results of the present survey indicate that after 6 years of regular operation, the workers at the HWI are not occupationally exposed to PCDD/Fs and other organic substances in their workplaces.  相似文献   
338.
Accelerated carbonation of municipal solid waste incineration fly ashes   总被引:3,自引:0,他引:3  
As a result of the EU Landfill Directive, the disposal of municipal solid waste incineration (MSWI) fly ash is restricted to only a few landfill sites in the UK. Alternative options for the management of fly ash, such as sintering, vitrification or stabilization/solidification, are either costly or not fully developed. In this paper an accelerated carbonation step is investigated for use with fly ash. The carbonation reaction involving fly ash was found to be optimum at a water/solid ratio of 0.3 under ambient temperature conditions. The study of ash mineralogy showed the disappearance of lime/portlandite/calcium chloride hydroxide and the formation of calcite as carbonation proceeded. The leaching properties of carbonated ash were examined. Release of soluble salts, such as SO4, Cl, was reduced after carbonation, but is still higher than the landfill acceptance limits for hazardous waste. It was also found that carbonation had a significant influence on lead leachability. The lead release from carbonated ash, with the exception of one of the fly ashes studied, was reduced by 2-3 orders of magnitude.  相似文献   
339.
In 2005, the concentrations of various metals and organic pollutants were analyzed in soils collected in different areas of Tarragona (Catalonia, Spain), where an important chemical/petrochemical complex is located. The levels of seven elements (As, Cd, Cr, Hg, Mn, Pb and V), as well as those of polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs) and polycyclic aromatic hydrocarbons (PAHs) were determined in soils, and compared with those obtained in a background study carried out in 2002. Only Cd and Pb showed significant higher concentrations in the petrochemical zone, while no significant differences were found for the remaining elements. In turn, vanadium was the only element showing a significant increase in the concentration between 2002 and 2005. With regard to the organic pollutants, no significant differences were found according to the area of sampling. However, an increase in naphthalene levels was observed during the period 2002-2005 in soils of the chemical and petrochemical areas. According to the present results, it is suggested that the levels of vanadium must be periodically monitored to assure that the important industrialization of Tarragona does not mean health risks for the population living near the complex.  相似文献   
340.
A neural-fuzzy approach to classify the ecological status in surface waters   总被引:2,自引:0,他引:2  
A methodology based on a hybrid approach that combines fuzzy inference systems and artificial neural networks has been used to classify ecological status in surface waters. This methodology has been proposed to deal efficiently with the non-linearity and highly subjective nature of variables involved in this serious problem. Ecological status has been assessed with biological, hydro-morphological, and physicochemical indicators. A data set collected from 378 sampling sites in the Ebro river basin has been used to train and validate the hybrid model. Up to 97.6% of sampling sites have been correctly classified with neural-fuzzy models. Such performance resulted very competitive when compared with other classification algorithms. With non-parametric classification-regression trees and probabilistic neural networks, the predictive capacities were 90.7% and 97.0%, respectively. The proposed methodology can support decision-makers in evaluation and classification of ecological status, as required by the EU Water Framework Directive.  相似文献   
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