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71.
Scott D. Lindsey Robert W. Gunderson J. Paul. Riley 《Journal of the American Water Resources Association》1992,28(5):865-875
ABSTRACT: Many hydrologic models have input data requirements that are difficult to satisfy for all but a few well-instrumented, experimental watersheds. In this study, point soil moisture in a mountain watershed with various types of vegetative cover was modeled using a generalized regression model. Information on sur-ficial characteristics of the watershed was obtained by applying fuzzy set theory to a database consisting of only satellite and a digital elevation model (DEM). The fuzzy-c algorithm separated the watershed into distinguishable classes and provided regression coefficients for each ground pixel. The regression model used the coefficients to estimate distributed soil moisture over the entire watershed. A soil moisture accounting model was used to resolve temporal differences between measurements at prototypical measurement sites and validation sites. The results were reasonably accurate for all classes in the watershed. The spatial distribution of soil moisture estimates corresponded accurately with soil moisture measurements at validation sites on the watershed. It was concluded that use of the regression model to distribute soil moisture from a specified number of points can be combined with satellite and DEM information to provide a reasonable estimation of the spatial distribution of soil moisture for a watershed. 相似文献
72.
Environmental planning,ecosystem science,and ecosystem approaches for integrating environment and development 总被引:3,自引:0,他引:3
D. Scott Slocombe 《Environmental management》1993,17(3):289-303
Currently popular concepts such as sustainable development and sustainability seek the integration of environment and development
planning. However, there is little evidence that this integration is occurring in either mainstream development planning or
environmental planning. This is a function of the history, philosophies, and evolved roles of both. A brief review of the
experience and results of mainstream planning, environmental planning, and ecosystem science suggests there is much in past
scientific and professional practice that is relevant to the goal of integrated planning for environment and development,
but still such commonly recommended reforms as systems and multidisciplinary approaches, institutional integration, and participatory,
goal-oriented processes are rarely achieved. “Ecosystem approaches,” as developed and applied in ecology, human ecology, environmental
planning, anthropology, psychology, and other disciplines, may provide a more transdisciplinary route to successful integration
of environment and development. Experience with ecosystem approaches is reviewed, their advantages and disadvantages are discussed,
and they are compared to traditional urban and regional planning, environmental planning, and ecosystem science approaches.
Ultimately a synthesis of desirable characteristics for a framework to integrate environment and development planning is presented
as a guide for future work and a criterion for evaluating existing programs. 相似文献
73.
Inconsistent findings have been reported in the few studies investigating the relationship between the perceived value of pay and incentive performance. One hundred and seventy-eight female incentive employees with a nine-week, non-judgmental performance measure responded to a developed valence of pay scale. This measure used items assessing the perceived ability of pay to address employee needs. Three factor-scales were found within these items. Support for the hypothesized positive relationship between pay valence and incentive performance was found, dependent on which of the three scales was used. These findings provide initial insight into the means by which pay, with its ability to address different needs, might provide differential employee motivation and performance levels. This study and future research issues are discussed. 相似文献
74.
75.
Dane Scott 《Journal of Agricultural and Environmental Ethics》2003,16(6):569-582
In 2001, it was announced thattransgenic DNA had introgressed intotraditional strains of maize in Mexico. Acontroversy erupted and raged throughout 2001and 2002. This episode represents an acutebreakdown in scientific discourse. Given thestakes in the genetically modified organismdebate, a breakdown in scientific discourse isalarming. The following inquiry looks into thecauses of this breakdown. Ultimately, it willbe argued that the underlying problem is thecurrent institutional structure of science,particularly in the United States. If thediagnosis is correct, then the proper course oftreatment is to pursue a program ofinstitutional reconstruction. 相似文献
76.
The opacity and emission performance of two “identical” cold-side precipitators at a power plant utilizing a Western coal source was investigated through an extensive test program. The test program included establishment of outlet emission versus opacity correlations for the two “identical” units, correlation of rapper strategy (frequency and amplitude) with opacity, and correlation of power-off rapping strategy with opacity. Analysis of the test program data demonstrates that the opacity-emission correlations from the two “identical” units can be significantly different. The potential reasons for the differences between the two units are identified and examined in light of the test program data. Strong correlation of opacity with rapping strategy was developed from the test program. Results demonstrate that an automatic power-off rapping technique can significantly enhance precipitator performance on ash from Western coal. 相似文献
77.
Problem: California's graduated driver licensing (GDL) program was implemented to reduce the high crash risk of teenage drivers. The program enhancements made in 1998 were evaluated in this study using methods that rule out the noticeable downward trend in California teen's fatal/injury crash rates as a possible explanation for any observed crash reductions that could otherwise be mistaken for program effects. Method: Monthly per capita fatal/injury crash rates for 15-to-17-year-olds and proportional representations of 16–17-year-olds' nighttime and passenger crashes were analyzed using intervention time series analysis. Results: After removing trend, seasonality, and transition effects in the data, no overall reductions in fatal/injury crashes for 15–17-year-olds or 16-year-olds (separately) were found to be associated with the 1998 program enhancements, suggesting no overall exposure reduction effect of the longer instruction permit period nor increased competency associated with the higher number of required practice hours. However, the 12-month nighttime and 6-month passenger restrictions were found to be associated with annual savings of 55 and 816 fatal/injury crashes, respectively. Discussion: Finding no overall impact of the 1998 GDL enhancements was not surprising given findings of an earlier survey suggesting that California teens and parents were largely already practicing program requirements prior to implementation and were not fully complying with the program requirements afterwards. Though the observed crash savings associated with the restrictions were of modest size, this is the first study to evidence a direct positive impact of the passenger restriction component of GDL programs. Larger reductions could be realized if the nighttime restriction started earlier and parents/law enforcement could be motivated to better enforce these restrictions. Impact on Industry: The findings provide support for passenger and nighttime restriction components of GDL programs. 相似文献
78.
79.
A safety self-management intervention for mining operations 总被引:4,自引:0,他引:4
PROBLEM: This quasi-experimental field study examined the efficacy of a safety self-management process to increase safety-related work practices in mining operations. METHODS: After a 7-week baseline, 15 miners participated in a safety self-management training and education presentation. The participants in a prebehavior condition (n=8) recorded their intentions to engage in specific percentages of safety-related work behaviors before starting their shift for the day. In contrast, participants in a postbehavior condition (n=7) recorded their percentages of safety-related work behaviors after their shift for the day. RESULTS: During withdrawal (4 weeks), the miners did not complete any self-monitoring forms. Based on 10,905 behavioral observations, safety self-management was effective at increasing the frequency of safety-related behavior (p<.05). For the prebehavior condition, the mean percent safe score across three target behaviors increased 34.8% during intervention. Similarly, in the postbehavior condition, the mean percent safe score across three target behaviors increased 40.1% during intervention. IMPACT ON INDUSTRY: The results suggest that employees who work in relative isolation or have little oversight, compared to traditional industrial workers, may benefit from a process by which they can systematically observe themselves. 相似文献
80.
Measuring Plant Diversity in the Tall Threetip Sagebrush Steppe: Influence of Previous Grazing Management Practices 总被引:2,自引:0,他引:2
In July 2000, a 490-ha wildfire burned a portion of a long-term grazing study that had been established in 1924 at the US Sheep Experiment Station north of Dubois, Idaho, USA. Earlier vegetation measurements in this tall
threetip sagebrush (Artemisia tripartita spp. tripartita) bunchgrass plant community documented significant changes in vegetation due to grazing and the timing of grazing by sheep. A study was initiated in May 2001 using 12 multiscale modified Whittaker plots to determine the consequences of previous grazing practices on postfire vegetation composition. Because there was only one wildfire and it did not burn all of the original plots, the treatments are not replicated in time or space. We reduce the potential effects of psuedoreplication by confining our discussion to the sample area only. There were a total of 84 species in the sampled areas with 69 in the spring-grazed area and 70 each in the fall- and ungrazed areas. Vegetation within plots was equally rich and even with similar numbers of abundant species. The spring-grazed plots, however, had half as much plant cover as the fall- and ungrazed plots and the spring-grazed plots had the largest proportion of plant cover composed of introduced (27%) and annual (34%) plants. The fall-grazed plots had the highest proportion of native perennial grasses (43%) and the lowest proportion of native annual forbs (1%). The ungrazed plots had the lowest proportion of introduced plants (4%) and the highest proportion of native perennial forbs (66%). The vegetation of spring-grazed plots is in a degraded condition for the environment and further degradation may continue, with or without continued grazing or some other disturbance. If ecosystem condition was based solely on plant diversity and only a count of species numbers was used to determine plant diversity, this research would have falsely concluded that grazing and timing of grazing did not impact the condition of the ecosystem. 相似文献