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91.
J. L. Sullivan R. J. Roberts 《Journal of the Air & Waste Management Association (1995)》2013,63(4):353-361
Environmental legislation is developing rapidly. In addition, considerable attention is being given to the environmental impact of new technological developments. Governments as well as citizens, often through organized groups are placing unprecedented pressures on many industries and even on other parts of the government. Popular feeling has been extremely strong on such matters and resistance so far has not been strong. This is likely to change substantially and the future may see a rapid increase in the number of environmental suits especially if the continued existence of certain industries is threatened. Expert evidence will be needed to support government legislation and to support actions to preserve the environment. Such measures will have inevitable economic implications and will evoke predictable responses. Reconciling these viewpoints will provide a challenge for the community which will probably depend to a larger extent on interpretation in courts of -law. The ability of various experts to give advice through the legal process will be essential if the most effective compromises are to be found. It is the purpose of this paper to discuss the gathering and use of such scientific evidence in environmental lawsuits. 相似文献
92.
John J. Roberts Edward J. Croke Samuel Booras 《Journal of the Air & Waste Management Association (1995)》2013,63(5):500-520
A study of the potential effectiveness of several strategies for reducing pollutant emissions from aircraft at a busy metropolitan airport has been carried out. This work is based on a model of emission-producing activities at the Hartsfield Atlanta International Airport and emissions from additional sources in the region surrounding the airport. A steady-state Gaussian plume dispersion model, developed previously,1-4 was used to determine pollutant concentrations at selected receptor sites. The model of the Atlanta airport was assembled to evaluate the results of a field test of one of the strategies (engine shutdown during taxiing) performed there in late 1973. The results of that field test are reported elsewhere.5,6 A full discussion of the interpretation of the comparison between modeled and monitored pollutant concentrations during the field test and the examination of alternative strategies noted, here are contained in the final report of this project.7 相似文献
93.
E.M. Roberts 《Journal of the Air & Waste Management Association (1995)》2013,63(6):632-637
In the field of air pollution control, the rare event is often of more significance than the common event. This is evidenced by the content of air quality standards which define acceptable upper limits of air pollution concentrations and acceptable frequencies with which such concentrations can be exceeded. The principles of extreme value statistics provide important tools for analyzing air quality data in an appropriately significant context. The purpose of this paper is twofold. First the principles of extreme value statistics are reviewed. The presentation is decidedly utilitarian; no attempt is made to derive more than the simplest propositions. The underlying assumptions of the theory are carefully pointed out and discussed. Particular emphasis is placed on the second largest value and its relation to the largest value. Exact probability distributions, and approximations to them, are derived in terms of the total population probability function. The more familiar and useful asymptotic distributions and their uses are presented and discussed. Part II of the paper will present applications of the theory to air quality data. 相似文献
94.
E.M. Roberts 《Journal of the Air & Waste Management Association (1995)》2013,63(7):733-740
In the field of air pollution control, the rare event is often of more significance than the common event. This is evidenced by the content of air quality standards which define acceptable upper limits of air pollution concentrations and acceptable frequencies with which such concentrations can be exceeded. The principles of extreme value statistics provide important tools for analyzing air quality data in an appropriately significant context. Part II of the paper presents applications of the theory to air quality data. First, application is made to decisions regarding the length of air monitoring experiments and the length of data records for dis-person analyses. The theory is then applied to the analysis of long term air pollution data collected by the South Coast Air Pollution Control District. The interrelations between extremes from monthly and annual samples are noted and are shown to be consistent with theory. 相似文献
95.
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97.
Yuki Hamada Douglas A. Stow Dar A. Roberts Janet Franklin Phaedon C. Kyriakidis 《Environmental monitoring and assessment》2013,185(4):3173-3190
Arid and semi-arid shrublands have significant biological and economical values and have been experiencing dramatic changes due to human activities. In California, California sage scrub (CSS) is one of the most endangered plant communities in the US and requires close monitoring in order to conserve this important biological resource. We investigate the utility of remote-sensing approaches—object-based image analysis applied to pansharpened QuickBird imagery (QBPS/OBIA) and multiple endmember spectral mixture analysis (MESMA) applied to SPOT imagery (SPOT/MESMA)—for estimating fractional cover of true shrub, subshrub, herb, and bare ground within CSS communities of southern California. We also explore the effectiveness of life-form cover maps for assessing CSS conditions. Overall and combined shrub cover (i.e., true shrub and subshrub) were estimated more accurately using QBPS/OBIA (mean absolute error or MAE, 8.9 %) than SPOT/MESMA (MAE, 11.4 %). Life-form cover from QBPS/OBIA at a 25?×?25 m grid cell size seems most desirable for assessing CSS because of its higher accuracy and spatial detail in cover estimates and amenability to extracting other vegetation information (e.g., size, shape, and density of shrub patches). Maps derived from SPOT/MESMA at a 50?×?50 m scale are effective for retrospective analysis of life-form cover change because their comparable accuracies to QBPS/OBIA and availability of SPOT archives data dating back to the mid-1980s. The framework in this study can be applied to other physiognomically comparable shrubland communities. 相似文献
98.
Bird Communities of Prairie Uplands and Wetlands in Relation to Farming Practices in Saskatchewan 总被引:1,自引:0,他引:1
Abstract: Modern farm practices can vary in their emphasis on tillage versus chemicals to control weeds, and researchers know little about which emphasis has greater ecological benefits. We compared avifaunas of uplands and wetlands in four treatments: conventional farms, conservation farms (contrasting those that minimized frequency of tillage [minimum tillage] with those that eliminated chemical inputs [organic]), and restored or natural (wild) sites in Saskatchewan, Canada. Of 37 different upland bird species encountered during surveys, one made greater use of farms, four made greater use of wild sites, and the remaining species showed no preference. When all upland species were combined, higher relative abundance occurred on wild than on farm sites, and on minimum tillage than on conventional farms. Wild upland sites also had more species than did conventional farms. Of 79 different species encountered during surveys of wetlands and their margins, most had similar encounter probabilities among treatments, although seven were more common on either organic farms or wild sites. Higher relative abundances were documented in wetland habitat of wild sites and organic farms than of minimum tillage or conventional farms. Wetlands of wild sites had more species than did minimum tillage or conventional farms. Overall, in terms of both avifaunal density and diversity, small treatment effects could be ascribed to differences between conventional and conservation farms, whereas larger effects were due to differences between farms and wild sites. Wetlands were heavily used by birds in all treatments, suggesting high conservation priority regardless of context. 相似文献
99.
100.
Belinda McFadgen Dave Huitema 《Journal of Environmental Planning and Management》2017,60(10):1765-1784
Environmental changes are increasing the need to understand complex cross-scale feedbacks in social–ecological systems. However, consistent conceptualisation of learning associated with environmental governance is lacking, and research mainly centres on individual variables. This paper identifies a typology of such learning, and theorises about configurations of variables. Focusing on experimentation as an intervention geared towards learning, it proposes a definition of policy experiment. A theoretical framework is presented, summarising a typology of experiments based on learning-related variables embedded in design choices, and reflected in institutional rule aggregations. The framework facilitates systematic analysis of real-world cases and testing of hypotheses on the effects of different types of experiment on learning. A case study demonstrates application of the framework. Results suggest future research paths that include attention to additional relevant variables. The findings have relevance for scholars interested in experimentation and learning, and environmental policy-makers considering experimentation to assess policy innovations. 相似文献