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811.
Agriculture's contribution to radiative forcing is principally through its historical release of carbon in soil and vegetation to the atmosphere and through its contemporary release of nitrous oxide (N2O) and methane (CHM4). The sequestration of soil carbon in soils now depleted in soil organic matter is a well-known strategy for mitigating the buildup of CO2 in the atmosphere. Less well-recognized are other mitigation potentials. A full-cost accounting of the effects of agriculture on greenhouse gas emissions is necessary to quantify the relative importance of all mitigation options. Such an analysis shows nitrogen fertilizer, agricultural liming, fuel use, N2O emissions, and CH4 fluxes to have additional significant potential for mitigation. By evaluating all sources in terms of their global warming potential it becomes possible to directly evaluate greenhouse policy options for agriculture. A comparison of temperate and tropical systems illustrates some of these options.  相似文献   
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As the U.S. auto industry tries to remain competitive in the face of evolving environmental rules, the new administration is presented with the opportunity to achieve environmental and economic goals through an industry-government partnership. The authors suggest a policy of total environmental quality as a starting point.  相似文献   
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The consideration of time in environmental research allows new insights into the fundamentals of environmental research and new pathways for perceiving and answering questions which might arise in environmental research. In order to take this all into account, one must realize that ecological systems have a history and that both the spatial aspects and the chronological expansion of these systems must be taken into consideration. Considering temporalities, rhythms and time scales as well as their interdependencies in environmental research and environmental protection enables us to obtain a better understanding. The significance of relationships and functions in ecological systems can be perceived better as well. The impact of pollutants as well as the outcome of human actions in ecology, and in economics and politics, is consequently mandatory for not only a spatial, but also for the involved temporal scales.  相似文献   
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Forum     
The State of Washington's Model Toxics Control Act cleanup standards, argues the author, provide the best available strategy for setting and achieving cleanup goals. Besides Protecting human health and the natural environnment, Washington's guidelines, which took effect March 1, 1991, incorporate enough flexibility to handle site-specific, finaical, and tehnological considerations. This column outlines the law's three approaches for defining cleanup levels for groundwater, surface water, air, industrial soils, and nonindustrial soils, comparing these methods with related methods in California, New Jersey, and New York.  相似文献   
819.
Is a company's in-house fitness center perceived as a place to engage in ‘leisure ’activities that are distinct from ‘work’, or as an extension of normal ‘work ’activities? This exploratory study examined the possibility that Protestant Work Ethic (PWE) beliefs might influence the frequency with which employees use their company's exercise programs and facilities. If exercise programs are regarded as ‘leisure’, then PWE endorsers would likely not participate, but the reverse might be true to the extent that such programs are seen as ‘work’. A short survey was completed by 335 employees of a large Canadian corporation which maintained an in-house fitness center that had been in operation for 16 months. The sample was almost evenly divided between users and non-users of the facilities. Results indicated that PWE endorsement was positively related both to the frequency with which respondents visited their company's fitness center, and to the perception that exercise provided work-related benefits, and these findings suggest that on-the-job fitness is regarded more as a component of ‘work ’than of ‘leisure’. ‘A corporate fitness program is the hottest perk since the executive washroom ’(Hoffman and Hobson, 1984, p. 110).  相似文献   
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