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781.
Six major ways in which individuals define the activity of working are empirically identified among national samples of employed labor force members in Belgium, Federal Republic of Germany, Israel, Japan, the Netherlands and the U.S.A. Several types of exchanges being made between working individuals and their working environments are suggested. Primary emphasis is placed upon national similarities and differences in work definition pattern distributions in the six nations. Secondary emphasis is placed upon the influence of demographic context and organizational role context on work definition patterns. Finally, an argument is made for different levels of appropriateness for two specific work definition patterns in work forces of the future. 相似文献
782.
Recent years have seen the environment emerge as one of the most pressing issues facing American business. Eventually, environmental costs will affect the bottom line of every American company. A recent study in the National Law Journal estimates that cleanup of the nation's known hazardous wastes sites will cost $752 billion over thirty years under current environmental policies. Environmental legislation and regulations impose annual compliance costs estimated by the Environmental Protection Agency at more than $30 billion. In the near future, environmental expenses for cleanup, regulatory compliance, and management are anticipated to grow to between 2.5 and 3 percent of GNP. Corporations that wish to be competitive must successfully manage these costs while maintaining or improving their role as responsible corporate citizens. Implementing a comprehensive system for identifying and managing environmental costs requires a multidisciplinary team effort. Environmental costs impact product selection, design and pricing, capital budgeting, and future strategic direction. In order to make informed and meaningful managerial decisions on environmental programs, real cost data are vital. An environmental management systems (EMS) requires information to set goals and then monitor progress towards those goals over time. This article will discuss the current cost accounting systems (CASs) available to support the myriad goals of environmental management systems. In addition, the article will outline a framework for plotting the location of your current EMS on a matrix of regulatory and information requirements and evaluating whether your corporation's CAS is adequate to support the goals and objectives set by your environmental management program. By anticipating future regulatory and information requirements, flexible systems can be developed to adapt to new and more stringent regulations and more complex information requirements. 相似文献
783.
784.
Thomas R. Wentworth George P. Johnson Russell L. Kologiski 《Journal of the American Water Resources Association》1988,24(2):389-396
ABSTRACT: Weighted averages (WA) was investigated as a vegetation-based method for wetland designation, to be used in conjunction with the wetland indicator status of plants from Wetland Plants of the United States of America 1986 (Reed, 1986). Ecological indices were assigned to indicator groups and were used to compute weighted averages for quantitative data obtained from four studies of wetland vegetation conducted in various regions of the United States. Weighted averages of vegetation data proved to be a useful tool for assessing wetland status of the vegetation types included in our study: (1) rankings of vegetation stands or types by WA correlated well with their positions on environmental moisture gradients; and (2) the results of WA could be used, together with a wetland/upland break-point, to designate vegetation types as wetland or upland in a way that agreed well, in three of the four studies, with an alternative classification of wetland habitats. The variation of weighted averages among the sampling units representing a vegetation type was generally small relative to the range of ecological indices assigned. However, designations based on weighted average scores close to the break-point should be considered provisional and must be verified with supplementary data on soils and hydrology. 相似文献
785.
Ecological risk assessment provides a methodology for evaluating the threats to ecosystem function associated with environmental
perturbations or stressors. This report documents the development of a conceptual model for assessing the ecological risk
to the water quality function (WQF) of bottomland hardwood riparian ecosystems (BHRE) in the Tifton-Vidalia upland (TVU) ecoregion
of Georgia. Previus research has demonstrated that mature BHRE are essential to maintaining water quality in this portion
of the coastal plain. The WQF of these ecosystems is considered an assessment endpoit—an ecosystem function or set of functions
that society chooses to value as evidenced by laws, regulations, or common usage. Stressors operate on ecosystems at risk
through an exposure scenario to produce ecological effects that are linked to loss of the desired function or assessment end
point. The WQF of BHRE is at risk because of the ecological and environmental quality effects of a suite of chemical, physical,
and biological stressors. The stressors are related to nonpoint source pollution from adjacent land uses, especially agriculture;
the conversion of BHRE to other land uses; and the encroachment of domestic animals into BHRE. Potential chemical, physical,
and biological stressors to BHRE are identified, and the methodology for evaluating appropriate exposure scenarios is discussed.
Field-scale and watershed-scale measurement end points of most use in assessing the effects of stressors on the WQF are identified
and discussed. The product of this study is a conceptual model of how risks to the WQF of BHRE are produced and how the risk
and associated uncertainties can be quantified. 相似文献
786.
Russell Schoof 《Journal of the American Water Resources Association》1983,19(1):15-21
ABSTRACT: West Bitter Creek floodwater retarding structure site 3 in South Central Oklahoma was instrumented and records obtained and analyzed to obtain information concerning an impoundment water budget that is useful to landowners and designers of these impoundments. On-site loss of water from the impoundment was only 17 percent of the inflow during three years when the annual precipitation averaged 26 inches and the annual inflow averaged 1.4 inches. Runoff from an eroded area with no farm ponds was about 70 percent greater per unit area than from a portion of the watershed where 71 percent of the drainage area was controlled by farm ponds. A previous study indicated, however, that the ponds were reducing runoff only 13 percent. Loss of top soil increases runoff considerably. Only 24 percent of the total runoff into the impoundment was base flow. The flow rate into the impoundment was less than 0.05 cfs 70 percent of the time, and the inflow rate exceeded 10 cfs only 1 percent of the time. SCS runoff curve numbers varied between 57 and 96 for the impoundment watershed with an inverse relation between precipitation amount and curve number apprently caused by partial area runoff from impervious and semi-impervious areas. A comparison of measured event runoff versus event runoff computed by the SCS curve numbers gave an r2 of only 0.44. However, the total computed surface runoff for eight years of record was less than 1 percent below the measured runoff which indicated the curve number method was a good tool for predicting long term runoff for the watershed. 相似文献
787.
Water scarcity is increasing internationally and now is also affecting the natural water resources of New Zealand. This paper explores two solutions at a local level—water-storage and water-sharing regimes—that address the problems of water scarcity and competition for water, towards more sustainable development. Both systems show positive effects on the local economy and for the local community, providing additional jobs to the region and increasing the value added. Environmental benefits mostly relate to a lessening of the impacts of water abstraction by keeping flow volumes above minimum requirements. Locally operated water-storage and water-sharing schemes thus can provide excellent governance strategies for water management, ensuring that local interest and issues are addressed adequately. 相似文献
788.
M. Amine Dahmani Kunchang Huang George E. Hoag 《Water, Air, & Soil Pollution: Focus》2006,6(1-2):127-141
This study has been conducted at the University of Connecticut (UCONN) in connection with the USEPA Superfund Innovative Technology
Evaluation (SITE) program to evaluate a chemical oxidation technology (sodium persulfate) developed at UCONN. A protocol to
assess the efficacy of oxidation technologies has been used. This protocol, which consists of obtaining data from a treatability
study, tested two in-situ chemical oxidation technologies that can be used on soil and groundwater at a site in Vernon, Connecticut.
Based on the treatability report results and additional field data collected at the site, the design for the field implementation
of the chemical oxidation remediation was completed. The results indicate that both sodium persulfate and potassium permanganate
were able to effectively degrade the target VOCs (i.e., PCE, TCE and cis-DCE) in groundwater and soil-groundwater matrices.
In the sodium persulfate tests (120 hrs), the extent of destruction of target VOCs was 74% for PCE, 86% for TCE and 84% for
cis-DCE by Na2S2O8 alone and 68% for PCE, 76% for TCE, and 69% for cis-DCE by Fe(II)-catalyzed Na2S2O8. The results demonstrate the sodium persulfate's ability to degrade PCE, TCE and cis-DCE. It is expected that given sufficient
dose and treatment time, a higher destruction rate of the dissolved phase contamination can be achieved. The data also indicates
that the catalytic effect of the iron chelate on persulfate chemistry was much less pronounced in the soil-groundwater matrix.
This indicates an interaction between the iron chelate solution and the soil, which may have resulted in a lower availability
of the chelated iron for catalysis. The study showed that the remediation of the VOCs-contaminated soil and groundwater by
in-situ chemical oxidation using sodium persulfate is feasible at the Roosevelt Mills site. As a result, the USEPA SITE program
will evaluate this technology at this site. 相似文献
789.
Michael D. Lebowitz Mary Kaye O'Rourke Russell Dodge Catharine J. Holberg Gregory Corman Robert W. Hoshaw Jack L. Pinnas Robert A. Barbee Mark R. Sneller 《Environment international》1982,8(1-6)
Asthmatic and nonasthmatic families in a representative community population sample have been monitored over a 2-year period using daily diaries. Simultaneous micro-indoor and outdoor monitoring has been conducted in a representative sample of houses for air pollutants, pollen, fungi, algae, and climate. Macromonitoring of air pollutants and pollen was conducted simultaneously. The relationship of indoor to outdoor and micro to macro factors can be demonstrated. Acute symptoms were strongly related to age, weakly related to sex, and not related to smoking habits. The qualitative relationship of these micro and macro factors to symptoms in asthmatic and nonasthmatic families have been explored. Suspended particulate matter and pollen were related to symptoms in asthmatics and nonasthmatics. Fungi might be related to symptoms as well. The use of gas stoves is qualitatively related to symptoms. Algae and other contaminants of evaporative coolers do not appear to be important in producing symptoms. More complex statistical analyses are required to determine interactions of these factors. Distinction has to be drawn between infectious episodes, allergic episodes, nonallergic but similar episodes, and asthmatic attacks. This study demonstrates the need for further investigations in this area. 相似文献
790.