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91.
Peter J. Pizor Sandra M. Holler 《Journal of the American Water Resources Association》1987,23(5):889-896
ABSTRACT: The growing concern for public participation in water resource decision-making has invited researchers to improve and develop reliable, quick, and inexpensive techniques for measuring public preferences. It is increasingly clear that traditional participation mechanisms, though useful, are no longer sufficient in providing the level of participation desired by many. A combination of microcomputer technology with Nominal Group Process (a step-by-step process ending in ranked recommendations) offers numerous possibilities for active participatory planning. Efforts at participation occurring through a well developed and defined process cannot be successful without a sensitivity to the conceptual, methodological, and pragmatic problems involved. This paper prefaces presentation of an alternative active process technique with discussion of the theoretical basis of participatory democracy and the frustration with practical implementation procedures. 相似文献
92.
Curtis A. Brown Wayne J. Graham 《Journal of the American Water Resources Association》1988,24(6):1303-1309
ABSTRACT: To facilitate decisions regarding the need for modification of potentially unsafe dams, the U.S. Bureau of Reclamation developed procedures for assessing the threat to human lives posed by the failure of individual dams. The procedures provide a conceptual model of the variables influencing the loss of life from dam failure and a method for predicting loss of life based on the size of the population at risk from failure and the amount of warning time available for that population. The prediction equations are based on an analysis of 24 dam failures and major flash floods occurring since 1950. Adjustments to the predictions to reflect special local conditions are also discussed. 相似文献
93.
This study explored the effects of union membership versus nonmembership on role based stress (i.e. ambiguity, overload, and interrole conflict), somatic complaints, and on the relationship between role stress and somatic complaints. The data analyzed came from the 1977 Quality of Employment Survey (Quinn and Staines, 1979). Only those respondents (N = 251) who held full-time nonsupervisory jobs in manufacturing were included in our sample. On the average, relative to nonmembers, union members reported higher levels of ambiguity and interrole conflict, but similar levels of overload and of somatic complaints. Union membership moderated the relationship between overload and somatic complaints. For union members, higher perceived performance of the union was associated with lower perceived stress and strain. We discuss the implications of those findings for further research on the impact of unions on stress, strain, and their interrelationship. 相似文献
94.
95.
Development of a bird integrity index: using bird assemblages as indicators of riparian condition 总被引:7,自引:0,他引:7
We describe the development of a bird integrity index (BII) that uses bird assemblage information to assess human impacts
on 13 stream reaches in the Willamette Valley, Oregon, USA. We used bird survey data to test 62 candidate metrics representing
aspects of bird taxonomic richness, tolerance or intolerance to human disturbance, dietary preferences, foraging techniques,
and nesting strategies that were affected positively or negatively by human activities. We evaluated the metric responsiveness
by plotting each one against a measure of site disturbance that included aspects of land use/land cover, road density, riparian
cover, and stream channel and substrate conditions. In addition, we eliminated imprecise and highly correlated (redundant)
metrics, leaving 13 metrics for the final index. Individual metric scores ranged continuously from 0 to 10, and index scores
were weighted to range from 0 to 100. Scores were calibrated using historical species information to set expectations for
the number of species expected under minimally disturbed conditions. Site scores varied from 82 for the least disturbed stream
reach to 8.5 for an urban site. We compared the bird integrity index site scores with the performance of other measures of
biotic response developed during this study: a fish index of biointegrity (IBI) and two benthic macroinvertebrate metrics.
The three assemblages agreed on the general level of disturbance; however, individual sites scored differently depending on
specific indicator response to in-stream or riparian conditions. The bird integrity index appears to be a useful management
and monitoring tool for assessing riparian integrity and communicating the results to the public. Used together with aquatic
indicator response and watershed data, bird assemblage information contributes to a more complete picture of stream condition. 相似文献
96.
Treatment of perchlorate‐contaminated groundwater using highly selective, regenerable ion‐exchange technology has been recently demonstrated at Edwards Air Force Base, California. At an influent concentration of about 450 μg/l ClO4?, the bifunctional anion‐exchange resin bed treated approximately 40,000 empty bed volumes of groundwater before a significant breakthrough of ClO4? occurred. The presence of relatively high concentrations of chloride and sulfate in site groundwater did not appear to affect the ability of the bifunctional resin to remove ClO4?. The spent resin bed was successfully regenerated using the FeCl3?HCl regeneration technique recently developed at the Oak Ridge National Laboratory, and nearly 100 percent of sorbed ClO4? was displaced or recovered after elution with as little as about two bed volumes of the regenerant solution. In addition, a new methodology was developed to completely destroy ClO4? in the FeCl3?HCl solution so that the disposal of perchlorate‐containing hazardous wastes could be eliminated. It is therefore anticipated that these treatment and regeneration technologies may offer an efficient and cost‐effective means to remove ClO4? from contaminated groundwater with significantly reduced generation of waste requiring disposal. © 2002 Wiley Periodicals, Inc. 相似文献
97.
Peggy A. Johnson Richard D. Hey Eric R. Brown David L. Rosgen 《Journal of the American Water Resources Association》2002,38(1):55-67
ABSTRACT: The number of stream restoration and enhancement projects being implemented is rapidly increasing. At road crossings, a transition must be created from the restored channel through the bridge or culvert opening. Given conflicting design objectives for a naturalized channel and a bridge opening, guidance is needed in the design of the transition. In this paper we describe the use of vanes, cross vanes, and w‐weirs, commonly used in stream restoration and enhancement projects, that may provide an adequate transition at bridges. Laboratory experiments were conducted on vanes and cross vanes to provide a transition for single span bridge abutments and on w‐weirs to provide a transition for double span bridges which have a pier in mid‐channel. The results of the experiments provided design criteria for transitions using each of the three structures. Prior field experience provided guidance on appropriate applications in terms of the stream and bridge characteristics. 相似文献
98.
Modeling the relationships between land use and land cover on private lands in the Upper Midwest, USA 总被引:4,自引:0,他引:4
This paper presents an approach to modeling land-cover change as a function of land-use change. We argue that, in order to model the link between socio-economic change and changes in forest cover in a region that is experiencing residential and recreational development and agricultural abandonment, land-use and land-cover change need to be represented as separate processes. Forest-cover change is represented here using two transition probabilities that were calculated from Landsat imagery and that, taken together, describe a Markov transition matrix between forest and non-forest over a 10-year period. Using a three-date land-use data set, compiled and interpreted from digitized parcel boundaries, and scanned aerial photography for 136 sites (c. 2500 ha) sampled from the Upper Midwest, USA, we test functional relationships between forest-cover transition probabilities, standardized to represent changes over a decade, and land-use conditions and changes within sample sites. Regression models indicated that about 60% of the variation in the average forest-cover transition probabilities (i.e. from forest to non-forest and vice versa) can be predicted using three variables: amount of agricultural land use in a site; amount of developed land use; and the amount of area increasing in development. In further analysis, time lags were evaluated, showing that agricultural abandonment had a relatively strong time-lag effect but development did not. We demonstrate an approach to using forest-cover transition probabilities to develop spatially-constrained simulations of forest-cover change. Because the simulations are based on transition probabilities that are indexed to a particular time and place, the simulations are improved over previous applications of Markov transition models. This modeling approach can be used to predict forest-cover changes as a result of socio-economic change, by linking to models that predict land-use change on the basis of exogenous human-induced drivers. 相似文献
99.
100.
This study assessed the incremental validity of different media for representing landscapes with significant dynamic elements. The experimental design independently varied the presence of motion and sound in different representations of a wild and scenic river in order to evaluate the adequacy or sufficiency of the surrogate to reflect physical changes in the landscape. Three representational conditions were identified: (1) video/sound, (2) video/no sound, and (3) static/no sound. A pilot study assessed the ability of the static images to represent river flow levels per se, and confirmed comparability with prior results (Brown & Daniel, 1989, Journal of Environmental Psychology, 7, 233–250). Scenic beauty judgments were then collected within each representational condition. Multiple regression analyses were used to determine the relationship of flow level to perceived scenic beauty for each representation condition. The results demonstrated that motion and sound, individually and conjointly, influenced judgements of scenic beauty for a landscape with a significant dynamic element. 相似文献