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China has embarked on major economic and social changes to revitalize the Chinese economy, increase labor productivity, and improve the material standard of living of the Chinese people. This paper assumes that China will achieve its goal of a per capita income of US$800 in 2000, open-door policies will be maintained, and nonfuel mineral commodity consumption will increase as GDP per capita increases. Projections are made of production, trade and consumption of 14 nonfuel minerals for the period 1985–2005. China is projected to increase its net imports to these 14 minerals from about US$5000 million in 1985 to about US$12000 million in constant dollars in 2005. China's investment climate will become more favorable for those multinational companies that bring with them clear comparative advantages in minerals exploration, mining and processing technologies and marketing, and are prepared to develop in-depth Chinese expertise. 相似文献
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The flagship of the Environmental Protection Agency's regulatory reinvention initiative, Project XL has been touted as a regulatory
blueprint for a site-specific, performance-based pollution-control system, but widespread complaints about the costs of the
program beg the question of whether the costs of tailoring regulations to individual facilities are manageable. To address
this question, this paper presents original survey data on a sample of 11 XL projects. We find that the fixed costs of putting
in place XL agreements are substantial, averaging over $450,000 per firm. While stakeholder negotiations are widely cited
as the principal source for these costs, we find that they actually arise mainly from interaction between participating facilities
and the EPA. Moreover, EPA management problems are perceived by our survey respondents as having inflated project development
costs. Finally, we find that the key factors that explains differences in costs across XL projects are the scope and complexity
of the project proposal. These findings suggest that Project XL favors large firms that can afford to pay significant project
development costs, that EPA management problems must be resolved to reduce costs, and that there may be a significant economic
bias against complex and innovative proposals—precisely the type of proposals that Project XL was designed to foster in order
to improve the efficiency of the regulatory system. 相似文献
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Use of an Airborne Lidar System to Model Plant Species Composition and Diversity of Mediterranean Oak Forests 总被引:2,自引:0,他引:2
Abstract: Airborne lidar is a remote‐sensing tool of increasing importance in ecological and conservation research due to its ability to characterize three‐dimensional vegetation structure. If different aspects of plant species diversity and composition can be related to vegetation structure, landscape‐level assessments of plant communities may be possible. We examined this possibility for Mediterranean oak forests in southern Portugal, which are rich in biological diversity but also threatened. We compared data from a discrete, first‐and‐last return lidar data set collected for 31 plots of cork oak (Quercus suber) and Algerian oak (Quercus canariensis) forest with field data to test whether lidar can be used to predict the vertical structure of vegetation, diversity of plant species, and community type. Lidar‐ and field‐measured structural data were significantly correlated (up to r= 0.85). Diversity of forest species was significantly associated with lidar‐measured vegetation height (R2= 0.50, p < 0.001). Clustering and ordination of the species data pointed to the presence of 2 main forest classes that could be discriminated with an accuracy of 89% on the basis of lidar data. Lidar can be applied widely for mapping of habitat and assessments of habitat condition (e.g., in support of the European Species and Habitats Directive [92/43/EEC]). However, particular attention needs to be paid to issues of survey design: density of lidar points and geospatial accuracy of ground‐truthing and its timing relative to acquisition of lidar data. 相似文献
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