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271.
Editor's note: Companies embracing TQEM must evaluate and change their manufacturing processes to stay globally competitive in the nineties. This article shows how an environmentally conscious manufacturing program incorporating new approaches to waste reduction will help companies achieve their corporatewide TQEM and strategic goals.  相似文献   
272.
ABSTRACT: Most hydrologic models require input parameters which represent the variability found across an entire landscape. The estimation of such parameters is very difficult, particularly on rangeland. Improved model parameter estimation procedures are needed which incorporate the small-scale and temporal variability found on rangeland. This study investigates the use of a surface soil classification scheme to partition the spatial variability in hydrologic and interrill erosion processes in a sagebrush plant community. Four distinct microsites were found to exist within the sagebrush coppice-dune dune-interspace complex. The microsites explained the majority of variation in hydrologic and interrill erosion response found on the site and were discernable based on readily available soil and vegetation information. The variability within each microsite was quite low and was not well correlated with soil and vegetation properties. The surface soil classification scheme defined in this study can be quite useful for defining sampling procedures, for understanding hydrologic and erosion processes, and for parameterizing hydrologic models for use on sagebrush range-land.  相似文献   
273.
EG&G is a Fortune 200 company with annual sales of $2.7 billion. It designs and manufactures laboratory and field-test instruments and electronic and mechanical components for commercial customers. EG&G provides systems engineering, precision component manufacturing, and test-site operating and management services to many government agencies and laboratories. It employs 34,000 people worldwide. Recognizing the need to improve its business practices as they related to environmental excellence, EG&G initiated policies, procedures, and programs to establish itself as an environmentally responsible company. Waste reduction was designated priority number one in EGG's environmental program. Our major customers are also making waste reduction a high visibility program. For example, on August 3, 1993, the president signed Executive Order 12856 making pollution prevention at federal facilities a goal of this administration. This article describes the EG&G Waste Reduction Pays (WARP) program, developed for use by all its operating entities, and why it is a model program to implement Executive Order 12856. It also depicts how the implementation of the program at federal facilities differs, in some respects, from that at other EG&G operating units.  相似文献   
274.
There is some concern in the environmental quality management (EQM) community that small and mid-sized companies do not have the technical, economic, and personnel resources or expertise to carry out significant programs of pollution prevention or waste reduction in the way that large corporations do. Thus, a very significant proportion of the economy may not be contributing to or benefiting from EQM approaches. This article begins to clarify what small and mid-sized companies that are committed to EQM can actually do and how this compares with the efforts of larger plants or plants operated as part of large multiplant corporations.  相似文献   
275.
Summary In the present paper efforts have been made to identify an environmentally sustainable and economically gainful strategy for agricultural development in the Himalayan region in Uttar Pradesh State, India. In the underdeveloped rural habitat that exists, a strategy, where the economics of environmentally sustainable development can be studied, is urgently required. The findings have been based on an empirical investigation of 150 sampled households spread over fifteen villages. It was found that the state of Himalayan agriculture and allied activities was in a critical condition, requiring urgent attention in order to improve the human environment. Suggested viable improvements in Himalayan agricultural development may be grouped into four categories, viz., an expansion of the cultivated area, where the land use pattern and other factors are discussed; full utilisation of irrigation potentialities, in which water management is discussed; improvement in the cropping pattern, where the whole system of cropping is analysed; and modifications in the use of agricultural appliances, specially in hoeing, ploughing and inter-culturing implements. Based on a critical analysis of these four identified aspects, economically viable, ecologically sound and socially justified environmental planning may be effectively framed.Dr H.C. Pokhriyal is Head of the Department of Economics at Garhwal University Campus, Tehri, and Dr N.S. Bist is Professor and Head of the Department of Economics at Garhwal University, Srinagar Garhwal, Himalaya, U.P., India.  相似文献   
276.
Food habits of white-tailed deer (Odocoileus virginianus) were examined from January to November 1984 via fecal-pellet analysis at Valley Forge National Historical Park (VFNHP), which represents an island habitat for deer surrounded by extensive urbanization, in southeastern Pennsylvania. In addition, use of fields by deer was compared to food habits. Herbaceous vegetation (forbs, leaves of woody plants, and conifer needles) was the predominant food type in all seasons except fall. Acorns and graminoids (grasses and sedges) were important food resources in fall and spring, respectively. Use of woody browse (twigs) was similar among seasons. Field use was relatively high during fall, winter without snow cover (<20 cm), and spring when food resources in fields were readily available. In contrast, use of fields was lowest in summer when preferred woodland foods were available and in winter with snow cover when food in fields was not readily accessible. Patterns of food-type use by deer at VFNHP indicate the year-round importance of nonwoody foods and field habitats to deer populations on public lands such as national parks in the northeastern United States.  相似文献   
277.
ABSTRACT: A cross-sectional data set of 80 lakes and reservoirs in nine southeastern states was examined to specify and parameterize trophic state relationships. The relationships fitted are based on measurements of several limnological variables taken over the course of a growing season or year in each of the lakes. The trophic state models relate phosphorus and nitrogen loading to inlake phosphorus and nitrogen concentrations, which in turn are related to maximum chlorophyll level, Secchi disk depth, dominant algal species, and hypolimnetic dissolved oxygen status. Due to the empirical nature of the study, causal conclusions are limited; rather, the models are most useful for prediction of average growing season conditions related to trophic state.  相似文献   
278.
Assessing ecological risk on a regional scale   总被引:17,自引:0,他引:17  
Society needs a quantitative and systematic way to estimate and compare the impacts of environmental problems that affect large geographic areas. This paper presents an approach for regional risk assessment that combines regional assessment methods and landscape ecology theory with an existing framework for ecological risk assessment. Risk assessment evaluates the effects of an environmental change on a valued natural resource and interprets the significance of those effects in light of the uncertainties identified in each component of the assessment process. Unique and important issues for regional risk assessment are emphasized; these include the definition of the disturbance scenario, the assessment boundary definition, and the spatial heterogeneity of the landscape. Although the research described in this article has been funded wholly or in part by the United States Environmental Protection Agency (EPA) through Interagency Agreement Number DW89932112-01-2 to the U.S. Department of Energy, it has not been subjected to EPA review and therefore does not necessarily reflect the views of EPA and no official endorsement should be inferred.  相似文献   
279.
280.
This report describes a study of stairway risk factors based on video tape recordings of workers using 31 flights of stairs selected from among the industries with the highest frequency and severity rates for stair-related injuries. The video tapes were reviewed to identify all incidents, i.e., falls, trips, slips, missteps, and moments of temporary instability. The characteristics of the 98 stair users who were involved in an incident were compared to the characteristics of a matched group of stair users who did not have incidents. The factors that best discriminated between the incident group and the nonincident group were: (a) The incident group tended to be those whose movement was impeded by others and who were older; and (b) The nonincident group tended to be those who were wearing glasses and those who were very large or heavy individuals. The influence of stairway physical features on the risk of injury was examined using correlation analysis. The measure of risk was the incidence rate (observed incidents per number of observed uses) for each flight as well as for each tread. Among the several variables significantly correlated with higher incidence rate are: (a) higher effective riser height and less effective tread depth; the safest stairs have an effective riser height not greater than 7 in. (18 cm) and an effective tread depth no less than 11 in. (27 cm); and (b) for descent only (92% of the injuries), the size of the nosing projection; it appears that nosing projections that exceed 1116 in. (1.8 cm) are associated with higher incidence rates.  相似文献   
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