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641.
Stephen A. Watson 《环境质量管理》1996,6(1):51-62
The ISO 14000 standards for environmental management systems (EMS) are voluntary standards intended to aid companies that wish to improve their environmental performance. The standards owe their existence, at least in part, to three widely shared views: (1) that existing environmental management systems are either inadequate or ineffective; (2) that companies will want to improve environmental performance for economic or social reasons; and (3) that governments and stakeholders will require companies to exercise greater control of the impacts to the environment through new regulations. ISO 14000 offers a solution—an ?integrated”? EMS, with components designed to effect sound management in any size organization and in any country. The standards are an embodiment of both the policy and practice of environmental management. This article is a consideration of the business implications of the ISO 14000 series of standards. How will a movement toward an integrated EMS be realized? Who will be in the best position to respond? ISO 14000 is a management system, and it carries with it business consequences. 相似文献
642.
Joseph E. Odencrantz Jeffrey G. Johnson Stephen S. Koenigsberg 《补救:环境净化治理成本、技术与工艺杂志》1996,6(4):99-114
An “oxygen barrier” was formed by depositing an oxygen-releasing compound in a series of wells that were placed perpendicular to the direction of groundwater flow at a site in Belen, New Mexico. The objective was to enhance the intrinsic bioremediation of dissolved phase BTEX contamination in the aquifer and to quantify the results. The oxygen was supplied by a controlled release formulation of magnesium peroxide called Oxygen Release Compound (ORC®), a virtually insoluble powder that is packaged in polyester filter socks. The areal distributions of the initial concentrations of dissolved oxygen and BTEX were measured and compared to the concentration changes at various times in the first 93 days of system operation. The concomitant reduction in BTEX can be seen in a series of contour plots. In 93 days, dissolved oxygen had dispersed at least 20-feet downgradient from the ORC source wells based on the pattern of decreasing BTEX concentrations. 相似文献
643.
644.
Older workers re-entering the workforce and those changing jobs are coming to play an increasingly important role in the labor force, especially as part-time workers. Yet the work orientation and job satisfaction of these workers has not been studied. Do ‘situational’ factors such as skill and pay matter for this subgroup of workers, and if so, which ones? If significant factors exist, can their effect be explained by the mediating influence of ‘dispositional’ factors like work values? This paper explores these questions in a study of 198 older workers who had begun new, mostly part-time jobs. Regression analysis shows that the intrinsic indicators for skill and autonomy have a positive effect on job satisfaction. No extrinsic factor was significantly related to satisfaction, indicating that these workers are more than ‘instrumentally’ oriented. This support for a ‘situational’ interpretation of the impact of work, especially intrinsic features, was sustained in analyses which incorporated work values. To the extent that the growing number of part-time jobs are relatively low-skilled, and to the extent that older workers in new jobs are influenced most by intrinsically rewarding work, there appears to be a growing mismatch between an occupational niche and those who are being sought to fill it. 相似文献
645.
The term overfishing is being used with increasing frequency to designate an undesirable level of fisheries exploitation. All too often, however, the term is taken as being self-evident. This article demonstrates that many definitions of overfishing are possible, depending essentially on what objective is being pursued for the fishery. Various possible biological and economic objectives are considered, both in a static and dynamic model of the fishery. Consideration is given to the best utilization of the fish stock from the viewpoint of the individual fishermen as well as that of society. It is shown that overfishing by one definition may be underfishing by another, and it is concluded therefore that anyone using the term overfishing ought, as a matter of course, to define it. 相似文献
646.
Stephen R. Kessell 《Environmental management》1977,1(1):39-48
Managers of wilderness resources must maintain, preserve, and sometimes restore pristine ecosystems while providing for public use and enjoyment of these areas. These managers require a resource information system that can store, retrieve and integrate basic data, synthesize components to solve particular problems, and provide simulations and predictions of natural processes and management actions. Traditional information systems based on land classification and type-mapping do not provide these capabilities.Gradient modeling, a new approach to resource management and forest fire simulation, has been developed to meet these needs in Glacier National Park. The method links four major components: (1) a terrestrial site inventory coded from aerial photographs that offers 10-m resolution; (2) gradient models of vegetation and fuel that derive quantitative stand compositional data from the parameters stored in the coded inventory; (3) a fuel moisture and microclimate model that extrapolates basestation weather data to remote sites using the parameters stored in the inventory; and (4) fire behavior and fire ecology models that integrate the data from the inventory and models to calculate real-time fire behavior and ecological succession following a fire. 相似文献
647.
Predicting the multiple pathways of plant succession 总被引:4,自引:0,他引:4
Peter J. Cattelino Ian R. Noble Ralph O. Slatyer Stephen R. Kessell 《Environmental management》1979,3(1):41-50
Classical concepts view succession as a deterministic, mechanistic regeneration of the disturbed community, and thus have limited applicability to fire-prone ecosystems, A recently developed multiple pathway succession model appears to have more realism and applicability in frequently disturbed ecosystems. It includes a set of species-specific attributes that are vital to reproduction and survival, and permits variable succession pathways depending on the stand's age (and thus species composition) when disturbed. Examples from Australia and the northern Rocky Mountains (USA) are presented, as are approaches to refining and improving the model. 相似文献
648.
Stephen J. Burges 《Journal of the American Water Resources Association》1979,15(1):227-243
ABSTRACT: Components contributing to uncertainty in the location of the flood plain fringe of a mapped flood plain are identified and examined to determine their relative importance. First-order uncertainty analysis is used to provide a procedure for quantifying the magnitude of uncertainty in the location of the flood plain fringe. Application of the procedure indicated that one standard deviation of uncertainty in flood plain inundation width was about one third of the mean computed inundation width for several flood population-flood geometry combinations. Suggested mapping criteria, which directly incorporate uncertainty estimates, are given. While these criteria are more suitable for use in developing areas than in flood plains that have had extensive development, the analysis procedure can be used to accommodate property owners who challenge the validity of estimated flood fringe boundaries. Use of uncertainty analysis in flood plain mapping should enhance the credibility of the final plan. 相似文献
649.
Carolyn E. Gombert Stephen T. Lancaster Gordon E. Grant Rebecca L. Flitcroft 《Journal of the American Water Resources Association》2023,59(4):615-634
In the Willamette River, OR, main channel temperatures can be too warm for cold water fishes, causing fish to concentrate in secondary channel features that provide thermal refugia. However, temperature regimes vary among and within features. Improved understanding of physical processes controlling thermal regimes is needed. This study developed a dimensionless index for assessment of thermal refugia on the upper Willamette River. The novel hyporheic insolation (HIN) index uses minimal field measurements to predict thermal refugia resulting from buffering. Continuous water temperature measurements at one side channel, eight alcoves, and six beaver ponds provided data to ground truth calculated predictions. Water temperature records were first used to characterize stratification at sites. Calculation of the Richardson number, an index of stability, showed two well-mixed sites and 13 stratified sites. At stratified sites, calculated values characterized the ratio of cooling flux from hyporheic discharge to heat flux from incoming solar radiation. As increased, measured temperatures at sites decreased. Despite overall scatter, a logarithmic fit to bin-averaged values showed R2 = 0.91. Calculations suggest that secondary channel features characterized by stratification and cool hyporheic discharge can provide thermal refugia. Accordingly, the HIN index may serve as a practical tool grounded in physical processes governing temperature across a floodplain. 相似文献
650.
Stephen M. Barrager 《Journal of the American Water Resources Association》1974,10(4):759-765
ABSTRACT: A case study is used to demonstrate a methodology for measuring the residential property value benefit of water pollution abatement. Increases in the value of single-family homes attributable to improvement in the water quality of the nearby Willamette River (Clackamas County, Oregon) were measured using a regression analysis technique. Sales prices and tax assessment data were used to estimate the change in property values coincident with the changes in water quality. The percentage increase in property value due to pollution abatement is expressed as a function of the distance between properties and the river bank. 相似文献