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This study focuses on two basic questions: Are voluntary programs effective in promoting higher environmental performance by participant firms? If so, which distinct areas of environmental performance are more likely to be improved by firms joining a voluntary environmental program? We address these questions by assessing the environmental effectiveness of the ski industry’s Sustainable Slopes Program in the western United States between 2001 and 2005. We found no evidence in our five-year analysis to conclude that ski areas adopting the SSP displayed superior performance levels than nonparticipants for the following areas of environmental protection: overall environmental performance, expansion management, pollution management, and wildlife and habitat management. SSP participants only appear to show a statistically significant correlation with higher natural resource conservation performance rates. For policymakers, these results suggest that caution is needed before a priori assuming that strictly voluntary programs can be effective in promoting comprehensive superior environmental performance. 相似文献
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The brick Chapel at St. Mary's City, Maryland, built around 1667, would have been an impressive structure on a colonial frontier where all the other buildings were built only of wood. While the building is no longer extant, the bricks remaining in the buried foundations hold information about the technologies and materials used by brickmakers in the 17th-century Chesapeake region. Instrumental neutron activation analysis (INAA) and petrographic analysis of thin sections were used to compare the Chapel bricks and other 17th-century bricks and tiles from several Chesapeake contexts to locally available clay sources. While the composition of the Chapel bricks is generally consistent with that of clays available in southern Maryland, these historic materials could not be linked to any one deposit, and may reflect the mixing of clays from multiple sources. In contrast, building materials from other 17th-century buildings at St. Mary's City could be more precisely “matched” to specific local clay deposits. This paper reports on our initial investigations toward understanding the technology of the Chapel bricks and their relationship to other bricks from St. Mary's City. 相似文献
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