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131.
Sagy Cohen G. Robert Brakenridge Albert Kettner Bradford Bates Jonathan Nelson Richard McDonald Yu‐Fen Huang Dinuke Munasinghe Jiaqi Zhang 《Journal of the American Water Resources Association》2018,54(4):847-858
Information on flood inundation extent is important for understanding societal exposure, water storage volumes, flood wave attenuation, future flood hazard, and other variables. A number of organizations now provide flood inundation maps based on satellite remote sensing. These data products can efficiently and accurately provide the areal extent of a flood event, but do not provide floodwater depth, an important attribute for first responders and damage assessment. Here we present a new methodology and a GIS‐based tool, the Floodwater Depth Estimation Tool (FwDET), for estimating floodwater depth based solely on an inundation map and a digital elevation model (DEM). We compare the FwDET results against water depth maps derived from hydraulic simulation of two flood events, a large‐scale event for which we use medium resolution input layer (10 m) and a small‐scale event for which we use a high‐resolution (LiDAR; 1 m) input. Further testing is performed for two inundation maps with a number of challenging features that include a narrow valley, a large reservoir, and an urban setting. The results show FwDET can accurately calculate floodwater depth for diverse flooding scenarios but also leads to considerable bias in locations where the inundation extent does not align well with the DEM. In these locations, manual adjustment or higher spatial resolution input is required. 相似文献
132.
Fisheries catches are known to be widely underreported, and much of their value flows in informal markets. Goods and services that are not directly sold in a market also have a corresponding economic value, here termed ‘shadow value’, which can apply to discarded fish—or those that are consumed but not sold (e.g., subsistence catches). Here, we estimate the monetary value of fisheries catches in Panama that are landed but not reported, or that are discarded at sea; this includes catches from artisanal and industrial fleets, as well as recreational and subsistence fisheries. Based on available data, we estimate that the market and shadow value of unreported catches in Panama in 2010 was around US$92 million, equal to approximately 43% of the total reported landed value. In the case of discarded fish, the shadow value represents the potential but entirely unrealized economic benefit of landing such fish; in the case of unreported landings, unreported market value represents only the first link in the potentially sophisticated informal seafood economy. One must be careful in considering these results for policy. It is possible that, rather than seeking to capture these ‘lost’ benefits, fish that are discarded or unreported should not have been caught at all, for example, if they are juveniles or of threatened species; conversely, unreported subsistence catches are crucial for food security throughout the world. These results help contextualize the scale of unreported fisheries in economic terms, and can inform subsequent policies and strategies to ensure social, ecological, and economic sustainability. 相似文献
133.
The aim of this paper is to propose a method for coupling national energy models, to identify the dividends of international cooperation in atmospheric pollution abatement and efficient energy use. It indicates, also, how to solve the resulting large‐scale multinational model. It simulates finally a cooperation of four European countries for curbing their carbon dioxide (CO2) emissions. 相似文献
134.
The present study deals with the development of an efficient and reliable process for safe disposal of coal fly ash to remove arsenic that has been found to be the most easily leachable and hazardous heavy metal in coal fly ash. Pre‐leaching of fly ash prior to disposal by a natural chelating agent, sodium gluconate (SG), was proposed and studied. Several operational factors influencing arsenic leachability, such as concentration of SG solution, liquid to solid ratio, pH, length of leaching time and leaching temperature were examined. Arsenic was found to leach out substantially with SG, but almost no further release was observed from the ash pre‐leached by SG. After the pre‐leaching treatment, the desirable high buffering capacity of the ash was well sustained. SG solution was effectively regenerated by activated alumina adsorption so that it could be successfully reused for multiple leaching/adsorption cycles. 相似文献
135.
MARINO BONAIUTO ANTONIO AIELLO MARCO PERUGINI MIRILIA BONNES ANNA PAOLA ERCOLANI 《Journal of environmental psychology》1999,19(4):353
This study tests a path model in which residential satisfaction, operationalized in terms of multidimensional perceived residential environment quality (PREQ), predicts neighbourhood attachment considered as the final criterion. Socio-demographic (age, sex, socio-economic level) and residential (length of residence both in the neighbourhood and in Rome, number of persons living together) variables are also included in the theoretical model as predictors of both PREQ and neighbourhood attachment. Using a multidimensional questionnaire for the measurement of PREQ and a unidimensional scale for the measurement of neighbourhood attachment, the study focuses on a sample of 497 inhabitants from 20 different neighbourhoods in the city of Rome. The multidimensional PREQ questionnaire comprises 20 different scales covering four main areas: architectural and town-planning features (six scales); social relations features (three scales); punctual and in-network services (six scales); context features (five scales). First, the path model is tested separately in each area using structural equation analysis. Then, the best predictors emerging from each area, together with all socio-demographic and residential variables, are included in a final model. This model shows both the relevance of predictors from all four areas in predicting attachment, and also a hierarchy between the areas in the power of the prediction (context area giving the most powerful predictors, services giving the weakest ones, architectural and town-planning, and social relations having intermediate importance). Length of residence in the neighbourhood and socio-economic level are the most relevant of the residential and socio-demographic variables. Results are discussed with reference to the multicomponential nature of the process of neighbourhood attachment. 相似文献
136.
Jonathan I. Eisen‐Hecht Randall A. Kramer 《Journal of the American Water Resources Association》2002,38(2):453-465
ABSTRACT: The primary objective of this study was to perform a cost‐benefit analysis of maintaining the current level of water quality in the Catawba River basin. Economic benefits were estimated using a stated preference survey method designed to value respondents' willingness to pay for a management plan to protect water quality in the Catawba basin over time. From the surveys conducted with 1,085 area residents, we calculated an annual mean willingness to pay of $139 for the management plan, or more than $75.4 million for all taxpayers in the area. Over the five‐year time horizon in which respondents were asked to pay for the management plan, this resulted in a total economic benefit of $340.1 million. The Watershed Analysis Risk Management Framework model was used to estimate the amount of management activities needed to protect the current level of water quality in the basin over time. Based on the model results, the total cost of the management plan was calculated to be $244.8 million over a ten‐year period. The resulting cost‐benefit analysis indicated that the potential benefits of this management plan would outweigh the costs by more than $95 million. 相似文献
137.
Precarious work or sustainable livelihoods? Aligning Prestea's Programme with the development dialogue on artisanal and small‐scale mining 下载免费PDF全文
Alternative livelihoods programmes (ALPs) are extensively executed in mining communities, often as models of development dialogue on artisanal and small‐scale mining (ASM). This paper assesses whether Prestea's ALP aligns with the development dialogue on artisanal mining. The conceptual design of ALP in Ghana's Prestea is based on the notions of substitution, homogenous community, and impact scalability. This paper argues that the Prestea ALP is not aligned with the development dialogue on artisanal mining, and therefore it is difficult to understand the role and function of environmentally‐damaging behaviours within livelihood strategies. The paper contends that it would be appropriate to concentrate on improving the existing artisanal miners’ operation of those most susceptible to resource access restrictions. Further, it may be more prudent to utilize livelihood‐centered interventions that create strong connections with sustainable development as a way of creating regular community engagements. Additionally, this paper argues that the term for the intervention programme on artisanal mining should be replaced with the broader term ‘livelihood‐centered intervention’. The replacement of the term ‘ALP’ avoids the tacit belief that ALP can adequately replace artisanal mining operations. Livelihood‐centered intervention should not necessarily utilize alternative livelihoods as direct behavioural change instruments. 相似文献
138.
There is extensive research on employee attitudes regarding employers and unions, but these studies have underemphasized social and affective forces. Most studies also examine attitudes toward either the union or the employer without considering how these attitudes might relate to one another. The present study of faculty (N = 306) at a large public research university demonstrated that perceptions of union support were positively related to union participation and perceptions of administration support were negatively related to union participation. Subjective norms and general union attitudes were related to perceptions of union support, and subjective norms were related to perceived organizational support. Taken together, an individual's participation in a union recognition effort depends not only on union instrumentality, but also upon social relationships with the union and administration. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
139.
Donna K. McNeese‐Smith 《组织行为杂志》1999,20(2):243-259
This ex‐post facto/correlational study examines the relationships among the following variables: nurse manager motivation for power, achievement and affiliation (N=19), managerial leadership behaviors, staff nurse outcomes of job satisfaction, productivity and organizational commitment (N=221) and patient satisfaction (N=299). Results show that managerial motivation for power is negatively correlated with manager use of leadership behaviors and staff nurse job satisfaction but positively correlated with patient satisfaction. Managerial motivation for achievement is positively correlated with use of leadership behaviors as well as nurse job satisfaction, productivity and organizational commitment, and generally to patient satisfaction. Managerial motivation for affiliation reveals few significant positive or negative relationships with other variables. The researcher concludes that both power and achievement motivation of the manager influence staff and patient outcomes in health care in the 1990s. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
140.
The emerging transactional or protean employment contract appears to have precipitated the development of a careerist orientation on the part of employees. This study examined the generalizability of the construct in a collectivist culture and the potential moderating influence of career growth opportunities on the careerist orientation–work attitude relationships. The results tend to support the generalizability of careerist orientation across cultures and, importantly, showed an absence of a moderating influence for career growth opportunities, suggesting that organizations cannot effectively counter the negative effects of careerist orientation on work attitudes. Limitations of the study, directions for future research, and implication of the findings for organizational dependence on employees as a competitive resource are discussed. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献