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21.
Curt Stern 《Die Naturwissenschaften》1932,20(12):193-201
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The accumulation of fire fuels in forests throughout the world contributes significantly to the severity of wildfires. To
combat the threat of wildfire, especially in the wildland-urban interface (WUI), US federal land management agencies have
implemented a number of forest restoration and wildfire risk reduction programs. In the spirit of revealed preference analyses,
the objective of this study is to investigate the pattern and determinants of National Fire Plan (NFP) expenditures for fuel
reduction treatments in northern New Mexico (USA). Estimation results from a set of Generalized Estimating Equations models
are mixed with respect to risk reduction hypotheses, and also raise issues regarding how risk reduction should be defined
for a region characterized by both pockets of urban sprawl into the WUI and large areas of chronic rural poverty. Program
preferences for project funding under the federal Collaborative Forest Restoration Program in New Mexico are shown to be distinctly
different (e.g., exhibiting greater concern for social equity) than for other NFP-funded projects. 相似文献
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It's about Time: Conservation Biology and History 总被引:1,自引:0,他引:1
Curt Meine 《Conservation biology》1999,13(1):1-3
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Anderson RR Martello DV White CM Crist KC John K Modey WK Eatough DJ 《Journal of the Air & Waste Management Association (1995)》2004,54(8):971-984
From October 1999 through September 2000, particulate matter (PM) with aerodynamic diameter > or =2.5 microm (PM2.5) mass and composition were measured at the National Energy Technology Laboratory Pittsburgh site, with a particle concentrator Brigham Young University-organic sampling system and a tapered element oscillating microbalance (TEOM) monitor. PM2.5 measurements had also been obtained with TEOM monitors located in the Pittsburgh, PA, area, and at sites in Ohio, including Steubenville, Columbus, and Athens. The PM data from all these sites were analyzed on high PM days; PM2.5 TEOM particulate mass at all sites was generally associated with transitions from locally high barometric pressure to lower pressure. Elevated concentrations occurred with transport of PM from outside the local region in advance of frontal passages as the local pressure decreased. During high-pressure periods, concentrations at the study sites were generally low throughout the study region. Further details related to this transport were obtained from surface weather maps and estimated back-trajectories using the hybrid single-particle Lagrangian integrated trajectory model associated with these time periods. These analyses indicated that transport of pollutants to the Pittsburgh site was generally from the west to the southwest. These results suggest that the Ohio River Valley and possible regions beyond act as a significant source of PM and its precursors in the Pittsburgh area and at the other regional sites included in this study. 相似文献
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