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401.
Miller JJ Handerek BP Beasley BW Olson EC Yanke LJ Larney FJ McAllister TA Olson BM Selinger LB Chanasyk DS Hasselback P 《Journal of environmental quality》2004,33(3):1088-1097
Southern Alberta, which has a cold climate dominated by strong chinook winds, has the highest density of feedlot cattle in Canada. However, the quantity and quality of runoff from beef cattle (Bos taurus) feedlots in this unique region has not been investigated. Our objectives were to compare runoff quantity (1998-2002) with catch-basin design criteria; determine concentrations of selected inorganic chemical parameters (1998-2000) in runoff in relation to water quality guidelines and the potential implications of irrigating adjacent crop-land; and determine if total heterotrophs, total coliforms, and Escherichia coli (1998-2000) persisted in the catch-basin water and soil. Runoff (< 0.1 to 42.5 mm) for a 24-h duration that included maximum peak discharge was less than the recommended design criteria of 90 mm based on runoff from 24 h of rainfall with a 30-yr return period. We found that curve numbers between 52 and 96 (mode of 90) were required to match the USDA Natural Resources Conservation Service predicted runoff and actual runoff volumes. Total P posed the greatest threat to water quality guidelines, and K posed the greatest threat for exceeding crop fertilizer requirements if catch-basin effluent was used as irrigation water. Water in the catch basin had continually high populations of E. coli throughout the study, with values ranging between log10 2 and log10 8 100 mL(-1). In contrast, soil in the catch basin generally had low populations of E. coli that were < log10 2 g(-1) wet wt., but at times higher populations between log10 2 and log10 6 g(-1) wet wt. were also found. 相似文献
402.
Brown JE King FG Mitchell WA Squier WC Harris DB Kinsey JS 《Journal of the Air & Waste Management Association (1995)》2002,52(4):388-395
In response to lingering concerns about the utility of dynamometer data for mobile source emissions modeling, the U.S. Environmental Protection Agency (EPA) has constructed an on-road test facility to characterize the real-world emissions of heavy-duty trucks. The facility was designed to effectively demonstrate the full range of vehicle operation and to measure the emissions produced. Since it began operation, the facility has been continuously upgraded to incorporate state-of-the-art technology. Its potential uses include collecting modal emissions data, validating dynamometer test parameters and results, and demonstrating new emission control technologies. 相似文献
403.
Scott MJ Brandt CA Bunn AL Engel DW Eslinger PW Miley TB Napier BA Prendergast EL Nieves LA 《Environmental management》2005,35(1):84-98
The Groundwater Protection Project at the US Department of Energy Hanford Site in Washington State is currently developing the means to assess the cumulative impact to human and ecological health and the regional economy and cultures from radioactive and chemical waste that will remain at the Hanford Site after the site closes. This integrated system is known as the System Assessment Capability (SAC). The SAC Risk/Impact Module discussed in the article uses media- and time-specific concentrations of contaminants estimated by the transport models of the integrated system to project potential impacts on the ecology of the Columbia River corridor, the health of persons who might live in or use the corridor or the upland Hanford environment, the local economy, and cultural resources. Preliminary Monte Carlo realizations from the SAC modeling system demonstrate the feasibility of large-scale uncertainty analysis of the complex relationships in the environmental transport of contaminants on the one hand and ecological, human, cultural, and economic risk on the other. Initial impact results show very small long-term risks for the 10 radionuclides and chemicals evaluated. The analysis also helps determine science priorities to reduce uncertainty and suggests what actions matter to reduce risks. 相似文献
404.
Wetland ecological and compliance assessments in the San Francisco Bay Region, California, USA 总被引:2,自引:0,他引:2
Breaux A Cochrane S Evens J Martindale M Pavlik B Suer L Benner D 《Journal of environmental management》2005,74(3):217-237
The San Francisco Bay Region of the California Regional Water Quality Control Board (SFB CRWQCB) and the San Francisco District of the US Army Corps of Engineers (US ACOE) are looking for an expeditious means to determine whether regulated wetland projects produce ecologically valuable systems and remain in compliance with their permits (i.e. fulfill their legal requirements) until project completion. A study was therefore undertaken in which 20 compensatory wetland mitigation projects in the San Francisco Bay Region were reviewed and assessed for both permit compliance and habitat function, and this was done using a rapid assessment method adapted for this purpose. Thus, in addition to determining compliance and function, a further goal of this study was to test the efficacy of the assessment method, which, if useful, could be applied not only to mitigation projects, but also to restoration projects and natural wetland systems. Survey results suggest that most projects permitted 5 or more years ago are in compliance with their permit conditions and are realizing their intended habitat functions. The larger restoration sites or those situated between existing wetland sites tend to be more successful and offer more benefits to wildlife than the smaller isolated ones. These results are consistent with regulatory experience suggesting that economies of scale could be realized both with (1) large scale regional wetland restoration sites, through which efforts are combined to control invasive species and share costs, and (2) coordinated efforts by regulatory agencies to track project information and to monitor the increasing number and size of mitigation and restoration sites. In regard to the assessment methods, we find that their value lies in providing a consistent protocol for evaluations, but that the ultimate assessment will rely heavily on professional judgment, regulatory experience, and the garnering of pre-assessment information. 相似文献
405.
Using longitudinal data collected in two waves, nine months apart, from 372 employees, this research is an empirical assessment of individual‐level change within an organizational setting. Specifically, strategies used by change implementers were operationalized as six transformational leader behaviors, and then hypothesized to influence employees' cynicism about organizational change (CAOC). A combination of social learning theory, and communication research served as the theoretical rationale to explain transformational leadership's hypothesized effects. As posited, transformational leader behaviors (TLB) generally were associated with lower employee CAOC. Further, the direction of causality was consistent in suggesting that the TLB reduced employee CAOC. A discussion concerning the ethical use of TLBs and recommendations for future research are provided. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
406.
E. Bruce Harrison 《环境质量管理》1992,1(3):225-231
Too often in the past, public relations professionals were consulted only when there was a problem—or a crisis—that needed explaining. The author provides a model for a process-oriented approach to environmental communication that focuses on building and sustaining positive public relationships over time. The key is dialogue with critical publics as well as links with other important actors in the environmental drama that can help position you as part of the solution, not the problem. 相似文献
407.
Bruce H. Kemelgor 《组织行为杂志》1982,3(2):147-160
This study represents an attempt to individualize values and job satisfaction. Using a specifically designed Value Scale and the J.D.I., a sample of 48 supervisors and 337 subordinates in six production organizations was investigated. It was found that those subordinates who indicate high job satisfaction tend to have value structures more similar to their superiors than do subordinates who evidence lower satisfaction. The implications of this value homogeneity within work groups were advanced and further research suggested. 相似文献
408.
Bruce L. Umminger 《Die Naturwissenschaften》1978,65(3):144-150
The known cases elucidating the role of hormones in the regulation of physiological and biochemical changes which occur when fish are acclimated to low temperatures are sparse, but evidence is accumulating to implicate prolactin, glucagon, insulin and perhaps thyroxine and cortisol in at least some of the physiological adjustments observed in some species. The need for further research on hormonal control mechanisms at work during low-temperature acclimation is discussed, with special emphasis placed on neuroendocrine relationships. 相似文献
409.
Bourgeois TG Hedman B Zalcman F 《Environmental pollution (Barking, Essex : 1987)》2003,123(3):451-462
Combined heat and power (CHP) is the simultaneous production of electrical or mechanical power and thermal energy from in a single process. Because thermal output from the generation of electricity is captured and utilized onsite, CHP systems can achieve efficiencies from 60% to as high as 90%. In contrast generation of electric power at sites remote from the loads served often results in efficiencies of 33% or less due to losses in generation and transmission and distribution of the power to ultimate end users. A well designed CHP system is the essence of energy efficiency. It may also provide significant environmental benefits. However, the full promise of CHP for improving the efficiency and productivity of businesses and the quality of the environment is unlikely to be realized given the current market structure and regulatory environment in which CHP projects are forced to compete. This paper examines the market structure and regulatory obstacles that hinder the development of more robust markets for CHP in New York State. 相似文献
410.
Bruce Vondracek Julie K. H. Zimmerman John V. Westra 《Journal of the American Water Resources Association》2003,39(5):1005-1015
ABSTRACT: The Agricultural Drainage and Pesticide Transport model was used to examine the relationship between fish and suspended sediment in the context of a proposed total maximum daily load (TMDL) in two agricultural watersheds in Minnesota. During a 50‐year simulation, Wells Creek, a third‐order cold water stream, had an estimated 1,164 events (i.e., one or more consecutive days of estimated sediment loading) and the Chippewa River, a fourth‐order warm water stream, had 906 events of measurable suspended sediment. Sublethal thresholds were exceeded for 970 events and lethal levels for 194 events for brown trout in Wells Creek, whereas adult nonsalmonids would have experienced sublethal levels for 923 events and lethal levels for 241 events. Sublethal levels were exceeded for 756 events and lethal thresholds were exceeded for 150 events in the Chippewa River. Nonsalmonids would have experienced 15 events of mortality between 0 and 20 percent in Wells Creek. In the Chippewa River, there were 35 events of mortality between 0 and 20 percent and one event in which mortality could have exceeded 20 percent. The Minnesota Pollution Control Agency has proposed listing stream reaches as being impaired for turbidity at 25 NTU, which is approximately 46 mg suspended sediment/1. We estimated that 46 mg/1 would be exceeded approximately 30 days in a year (d/yr) in both systems. A TMDL of 46 mg SS/1 may be too high to ensure that stream fishes are not negatively affected by suspended sediment. We recommend that an indicator incorporating the duration of exposure be applied. 相似文献