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241.
Public support for biodiversity conservation is shaped by people's values and their knowledge, beliefs, and attitudes toward the environment. We conducted the first multinational representative survey of the general public's perceptions of river fish biodiversity in France, Germany, Norway, and Sweden. For the online survey, 1000 respondents per country were randomly selected from large panels following country-specific quotas set on age, gender, and educational level. Questions covered people's level of knowledge, beliefs, values, and attitudes toward river fish, environmental threats, and conservation measures. We found that the public had limited knowledge of freshwater fishes. Two non-native species, rainbow trout (Oncorhynchus mykiss) and brook trout (Salvelinus fontinalis), were widely perceived as native, whereas native Atlantic salmon (Salmo salar) was mostly classified as native in Scandinavia and largely as non-native in central Europe. These results suggest an extinction of experience paralleling the extirpation or decline of salmon stocks in countries such as Germany and France. Respondents thought pollution was the dominant threat to riverine fish biodiversity. In reality, habitat loss, dams, and the spread of non-native fishes are equally important. Despite limited biological knowledge, respondents from all countries held an overwhelmingly proecological worldview, supported conservation stocking, and appreciated native fishes, although only a minority interacted with them directly. Differences among the 4 countries related to several conservation issues. For example, threats to biodiversity stemming from aquaculture were perceived as more prevalent in Norway compared with the other 3 countries. Promoting fish conservation based on charismatic species and use values of fishes may work well in countries with a strong economic and cultural link to the freshwater environment, such as Norway. In countries where people rather abstractly care for nature, focusing conservation messaging on broader ecosystem traits and non-use values of fishes is likely to win more support.  相似文献   
242.
The magnitude of damage due to a vapor cloud explosion can be estimated in many ways, ranging from look-up tables to quantitative risk analysis. An explosion overpressure analysis is a routine part of compliance with the American Petroleum Institute (API) Recommended Practice (RP) 752 when evaluating occupied buildings in a facility that processes flammable or reactive materials. In many cases, a risk-based approach is useful because consequence modeling studies often indicate major problems for buildings at existing facilities. One of the most common risk-based methods, overpressure exceedance, incorporates a wide range of potential explosion scenarios coupled with the probability of each event to develop the probability of exceeding a given overpressure at specific locations. But this and other methods that only use overpressure may not represent an accurate building response. By combining the risk-based methodology of the exceedance analysis with pressure and impulse data in the form of pressure–impulse (P–I) curves, a better measure of building damage can be generated. P–I curves for blast loading determination have been in use for decades, and allow the user to determine levels of damage based on a predicted overpressure and its corresponding impulse. Curves have been published for entire buildings, individual structural members, window breakage, and even consequences to humans. This paper will explore application of P–I curves for building damage, and will highlight some of the benefits, as well as some of the potential problems, of using P–I curves.  相似文献   
243.
244.
River systems are increasingly under stress and pressure from agriculture and urbanization in riparian zones, resulting in frequent engineering interventions such as bank stabilization or flood protection. This study provides guidelines for a more sustainable approach to river management based on hydrogeomorphology concepts applied to three contrasted rivers in Quebec (Canada). Mobility and flooding spaces are determined for the three rivers, and three levels of “freedom space” are subsequently defined based on the combination of the two spaces. The first level of freedom space includes very frequently flooded and highly mobile zones over the next 50 years, as well as riparian wetlands. It provides the minimum space for both fluvial and ecological functionality of the river system. On average for the three studied sites, this minimum space was approximately 1.7 times the channel width, but this minimum space corresponds to a highly variable width which must be determined from a thorough hydrogeomorphic assessment and cannot be predicted using a representative average. The second level includes space for floods of larger magnitude and provides for meanders to migrate freely over a longer time period. The last level of freedom space represents exceptional flood zones. We propose the freedom space concept to be implemented in current river management legislation because it promotes a sustainable way to manage river systems, and it increases their resilience to climate and land use changes in comparison with traditional river management approaches which are based on frequent and spatially restricted interventions.  相似文献   
245.
We identified factors that are important determinants of body burdens (breast milk levels) of polychlorinated biphenyls (PCBs), dioxins (polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs)) and polybrominated diphenyl ethers (PBDEs). PCBs, PCDD/Fs and PBDEs were analysed in breast milk from up to 325 first-time mothers in Uppsala, Sweden, who delivered between 1996 and 2006. Hierarchical clustering was used as a method for identification of groups of compounds with common sources of exposure and similar toxicokinetics. Based on correlations between levels of single compounds/congeners in breast milk, distinctly separated clusters were formed, strongly dependent on structural similarities of the organohalogen molecules. In a multiple regression model, levels of PCBs (except PCB 28), PCDD/Fs and BDE-153 were positively associated with age of the mother and weight loss after delivery and inversely associated with pre-pregnancy BMI (body mass index) and weight gain during pregnancy. Higher levels of mono-ortho PCB TEQ, non-ortho PCB TEQ and BDE-153 in milk were found among women with high physical activity. Women who were breastfed during infancy and grew up on the Baltic coast of Sweden, with high availability of contaminated fish from the Baltic sea, had higher levels of PCBs and PCDD/Fs in breast milk indicating that exposure early in life from breast milk and contaminated fish may still affect body burdens at the time of pregnancy. The importance of current consumption of fatty Baltic fish as a source of exposure was supported by the positive association with breast milk levels of mono-ortho PCB TEQ, PCDF TEQ and BDE-153. The results show that, in contrast to the lower brominated PBDE congeners, the hexa-brominated BDE-153 resembles the chlorinated compounds with regards to determinants in breast milk. This suggests that some of the PBDEs may have toxicokinetic properties and that are similar to the PCBs and PCDD/Fs. Our results show that a few simple advices to women regarding weight changes in connection with pregnancy and consumption of contaminated fatty fish during the whole lifetime may lower the levels of dioxins in breast milk by up to 60%.  相似文献   
246.
As it is often difficult to obtain sufficient numbers of measurements to adequately characterise exposure levels, occupational exposure models may be useful tools in the exposure assessment process. This study aims to refine and validate the inhalable dust algorithm of the Advanced REACH Tool (ART) to predict airborne exposure of workers in the pharmaceutical industry. The ART was refined to reflect pharmaceutical situations. Largely task based workplace exposure data (n = 192) were collated from a multinational pharmaceutical company with exposure levels ranging from 5 × 10(-5) to 12 mg m(-3). Bias, relative bias and uncertainty around geometric mean exposure estimates were calculated for 16 exposure scenarios. For 12 of the 16 scenarios the ART geometric mean exposure estimates were lower than measured exposure levels with on average, a one-third underestimation of exposure (relative bias -32%). For 75% of the scenarios the exposure estimates were, within the 90% uncertainty factor of 4.4, as reported for the original calibration study, which may indicate more uncertainty in the ART estimates in this industry. While the uncertainty was higher than expected this is likely due to the limited number of measurements per scenario, which were largely derived from single premises.  相似文献   
247.
Laforce, Serge, Marie‐Claude Simard, Robert Leconte, and François Brissette, 2011. Climate Change and Floodplain Delineation in Two Southern Quebec River Basins. Journal of the American Water Resources Association (JAWRA) 47(4):785‐799. DOI: 10.1111/j.1752‐1688.2011.00560.x Abstract: A methodology is presented for mapping the flooded extent of rivers under projected climate change. The methodology follows a top‐down modeling approach, where future climate projections generated by global climate models (GCMs) are downscaled to the watershed scale and used as input to hydrological and hydrodynamic models for predicting future river flows and associated open water levels. A range of possible future climate responses are taken into account, allowing quantification of flood‐mapping uncertainties resulting from GCM structure and greenhouse gas emission scenarios (GHGES). Probabilistic projections of future flood zones are developed by assuming that all GCMs and GHGES be equally weighted. The proposed methodology was applied to two river basins located in southern Quebec, Canada, for the time horizons 2020 and 2080. Twenty‐ and hundred‐year floods were computed and corresponding flood maps have been produced. Results indicate that there is a general trend toward an increased spring peak discharge for the Châteauguay River Basin and a decrease for the du Nord River Basin at the 2020 horizon. A less obvious trend was observed for the 2080 horizon, some GCM‐GHGES producing an increase in spring peak flows, whereas others would result in a less severe spring flood. These uncertainties in flood flows have cascaded into uncertainties in the corresponding flooded extent and represented as probabilistic flood maps.  相似文献   
248.
Prior research supports a link between organizational culture and performance but generally falls short of establishing causality or determining the direction of a culture–performance (C‐P) relationship. Using data collected from 95 franchise automobile dealerships over 6 years, we studied longitudinal culture–performance relationships to determine whether culture or performance has causal priority, or alternatively, whether a reciprocal relationship exists. Results from cross‐lagged panel analyses indicate that culture “comes first,” consistently predicting subsequent ratings of customer satisfaction and vehicle sales. Furthermore, the positive effect of culture on vehicle sales is fully mediated by customer satisfaction ratings. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
249.
A field and laboratory geotechnical characterization study of a Municipal Solid Waste Incineration Ash disposed of at the Carleton Farms monofill in Michigan was performed. Field characterization consisted of field observations, collection of four bulk samples and performance of shear wave velocity measurements at two locations. Laboratory characterization consisted of basic geotechnical characterization, i.e., grain size distribution, Atterberg limits, specific gravity tests, compaction tests as well as moisture and organic content assessment followed by direct shear and triaxial shear testing. The test results of this investigation are compared to results in the literature. The grain size distribution of the samples was found to be very similar and consistent with the grain size distribution data available in the literature, but the compaction characteristics were found to vary significantly. Specific gravities were also lower than specific gravities of silicic soils. Shear strengths were higher than typically reported for sandy soils, even for MSWI ash specimens at a loose state. Strain rate was not found to impact the shear resistance. Significant differences in triaxial shear were observed between a dry and a saturated specimen not only in terms of peak shear resistance, but also in terms of stress–strain response. In situ shear wave velocities ranged from 500 to 800 m/s at a depth of about 8 m, to 1100–1200 m/s at a depth of 50 m. These high shear wave velocities are consistent with field observations indicating the formation of cemented blocks of ash with time, but this “ageing” process in MSWI ash is still not well understood and additional research is needed. An improved understanding of the long-term behavior of MSWI ash, including the effects of moisture and ash chemical composition on the ageing process, as well as the leaching characteristics of the material, may promote unbound utilization of the ash in civil infrastructure.  相似文献   
250.
The environmental assessment of potential effects of contaminated harbor sediments stabilized with hydraulic binders and the determination of remediation endpoints require the determination of pollutants leaching potentials. Moreover, little information about the speciation and mobility of inorganic contaminants in these specific solid matrices is available in the literature. The objective of this paper is to investigate the relationship between mineralogy and leachability of contaminants (copper, lead, and zinc) present in a French harbor sediment stabilized with quicklime and Portland cement. Batch equilibrium leaching tests at various pH, chemical analysis of leachates, and mineralogical studies (X-ray diffraction, scanning electron microscopy–energy dispersive spectroscopy, and diffuse reflectance infrared Fourier transform) have been combined in the present investigation. The acid neutralization capacity of the stabilized matrix studied is first controlled by the dissolution of portlandite (pH?~12), followed by the dissolution of C–S–H (pH?~11) and the dissolution of ettringite (pH?~10). Finally, a very high buffering capacity of this stabilized sediment is observed for pH values around 6. This equilibrium is mainly controlled by the dissolution of iron sulfides and carbonate minerals. Consequently, the mobilization of inorganic contaminants as a function of pH remains very low (<0.1 wt%) for pH values above 6 and significantly increases for pH below these values. This research confirms the importance of a combined methodology for the intrinsic characterization of potential mobilization of contaminants in a stabilized sediment and for a better understanding of geochemical processes that affect contaminant fate, transformation, and transport in the subsurface environment.  相似文献   
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