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611.
Larry Larsen Terri Morrell David Wood Meghan Gallione Bruce Guerard Judith Karinen Kip Petersen Frederick Steiner 《Environmental management》1991,15(4):531-548
This is the second of three articles prepared to explain the Teller County growth management process. As part of an ongoing
growth management process in Teller County, Colorado, opportunities and constraints for development and conservation were
identified. The scenic mountain county faces a number of issues because of growth. The recognition of those issues has resulted
in the goal to direct future growth to the most appropriate and cost-effective places. To determine those places that are
best for new development, thorough ecological inventories were conducted for the entire county as well as for the City of
Woodland Park area. From these inventories, environmentally sensitive areas were identified. The environmentally sensitive
areas were considered constraints in conducting suitability analyses for a variety of potential land uses. The suitability
analyses resulted in the identification of opportunities for future growth in Teller County generally as well as the more
specific Woodland Park planning area. This article, like the other two, is part of a reflective analysis by the planners who
were involved.
Paper 2 in a series 3. 相似文献
612.
Marybeth Buechner Christine Schonewald-Cox Raymond Sauvajot Bruce A. Wilcox 《Environmental management》1992,16(6):799-809
In recent years, cross-boundary management has become an essential part of park management. In this article we compare the
perspectives of managers of several US national parks to the advice on this issue presented in the published literature. Data
were obtained from interviews of the superintendents, assistant superintendents and resources managers of five major western
national parks and from a survey of participants in a NPS workshop attended by park superintendents, scientists, and resource
managers; law enforcement personnel; and interpreters. Three themes related to boundary management were consistently stressed
by park managers: (10 a lack of sufficient funds and personnel within the parks; (2) the need for reliable information on
both political and natural processes; and, (3) the importance of personal interactions between park staff and individuals
from the surrounding area. Basic data collection, the documentation of trends, cooperative groups and personal contacts, educational
programs, and land acquisition were the most useful strategies. A lack of funds and information, ineffective communication,
enforcement problems, and a lack of motivation for parties to reach a negotiated agreement were the most serious obstacles.
A wide range of valuable institutional knowledge concerning boundary management exists within the National Park Service; however,
there appears to be a gap between published strategies and the approaches that work “on the ground”. 相似文献
613.
Bruce Hicks Robert McMillen Robert S. Turner George R. Holdren Jr Timothy C. Strickland 《Environmental management》1993,17(3):343-353
Methods are discussed for describing patterns of current wet and dry deposition under various scenarios. It is proposed that
total deposition data across an area of interest are the most relevant in the context of critical loads of acidic deposition,
and that the total (i.e., wet plus dry) deposition will vary greatly with the location, the season, and the characteristics
of individual subregions. Wet and dry deposition are proposed to differ in such fundamental ways that they must be considered
separately. Both wet and dry deposition rates are controlled by the presence of the chemical species in question in the air
(at altitudes of typically several kilometers in the case of wet deposition, and in air near the surface for dry). The great
differences in the processes involved lead to the conclusion that it is better to measure wet and dry deposition separately
and combine these quantifications to produce “total deposition” estimates than to attempt to derive total deposition directly.
A number of options for making estimates of total deposition to be used in critical loads assessment scenarios are discussed
for wet deposition (buckets and source receptor models) and for dry deposition (throughfall, micrometeorology, surrogate surfaces
and collection vessels, inference from concentrations, dry-wet ratios, and source-receptor models).
The research described in this article has been funded by the US Environmental Protection Agency. This document has been prepared
at the EPA Environmental Research Laboratory in Corvallis, Oregon, through contract #68-C8-0006 with ManTech Environmental
Technology, Inc., and Interagency Agreement #1824-B014-A7 with the U.S. Department of Energy and at Oak Ridge National Laboratory
managed by Martin Marietta Energy Systems, Inc., under Contract DE-AC05-84OR21400 with the US Department of Energy. Environmental
Sciences Division Publication No. 3905. It has been subjected to the Agency’s peer and administrative review and approved
for publication. Mention of trade names or commercial products does not constitute endorsement or recommendation for use. 相似文献
614.
Socioeconomic, demographic, and attitudinal factors likely to influence individual initiative to use control measures against
gypsy moth infestation in New Hampshire are examined. Data were acquired through a mail survey from 629 individuals in three
targeted towns: Bow, Conway, and Exeter. Using logit regression analysis, numerous variables are shown to be statistically
significant in influencing an individual's willingness to use control measures. The influencing factors include: the individual
knowing the difference between the gypsy moth caterpillar and the eastern tent caterpillar; the individual being a homeowner
rather than a renter; the number of acres of land accompanying the individual's dwelling; the number of trees on the individual's
property; the individual's gender; and the individual's level of income. Aesthetic damage and the nuisance caused by gypsy
moth infestation were the primary reasons for individuals to use control measures. The results from this study indicate that
the motivation behind an individual's initiative to use control measures is influenced by diverse and varying factors. The
models, methodology, and results as applied and presented here are exploratory in nature, yet could prove informative for
researchers seeking a greater understanding of the interaction between humans and insect pests. 相似文献
615.
616.
617.
T Scott Rupp Mark Olson Layne G Adams Bruce W Dale Kyle Joly Jonathan Henkelman William B Collins Anthony M Starfield 《Ecological applications》2006,16(5):1730-1743
Caribou are an integral component of high-latitude ecosystems and represent a major subsistence food source for many northern people. The availability and quality of winter habitat is critical to sustain these caribou populations. Caribou commonly use older spruce woodlands with adequate terrestrial lichen, a preferred winter forage, in the understory. Changes in climate and fire regime pose a significant threat to the long-term sustainability of this important winter habitat. Computer simulations performed with a spatially explicit vegetation succession model (ALFRESCO) indicate that changes in the frequency and extent of fire in interior Alaska may substantially impact the abundance and quality of winter habitat for caribou. We modeled four different fire scenarios and tracked the frequency, extent, and spatial distribution of the simulated fires and associated changes to vegetation composition and distribution. Our results suggest that shorter fire frequencies (i.e., less time between recurring fires) on the winter range of the Nelchina caribou herd in eastern interior Alaska will result in large decreases of available winter habitat, relative to that currently available, in both the short and long term. A 30% shortening of the fire frequency resulted in a 3.5-fold increase in the area burned annually and an associated 41% decrease in the amount of spruce-lichen forest found on the landscape. More importantly, simulations with more frequent fires produced a relatively immature forest age structure, compared to that which currently exists, with few stands older than 100 years. This age structure is at the lower limits of stand age classes preferred by caribou from the Nelchina herd. Projected changes in fire regime due to climate warming and/or additional prescribed burning could substantially alter the winter habitat of caribou in interior Alaska and lead to changes in winter range use and/or population dynamics. 相似文献
618.
Conservation and the Social Sciences 总被引:16,自引:0,他引:16
619.
620.
D. Wilson Freshwater Andrew Hines Seth Parham Ami Wilbur Michelle Sabaoun Jennifer Woodhead Lad Akins Bruce Purdy Paula E. Whitfield Claire B. Paris 《Marine Biology》2009,156(6):1213-1221
Lionfish are popular aquarium fish from the Indo-Pacific that have invaded the western Atlantic. Two species, Pterois volitans and P. miles, were well established along the United States east coast before the first lionfish were reported from the Bahamas in 2004,
where they quickly dispersed throughout the archipelago by 2007. The source of the Bahamian lionfish invasion has been in
question because of the hypothesized low connectivity between Florida and Bahamas reef species as well as the temporal lag
in their arrival in the Bahamas. Mitochondrial control region haplotypes (680 bp) were determined and analyzed for lionfish
specimens from the Bahamas, North Carolina, and two sites within their native range (Indonesia and the Philippines). Exact
tests, pairwise F
st and AMOVA analyses all showed no significant differentiation between the Bahamas and North Carolina specimens. The similarity
between the Bahamas and North Carolina lionfish was also reflected in a minimum spanning network and neighbor-joining distance
tree generated from the data. Sequence analyses also revealed the presence of only Pterois volitans, as no P. miles were detected in the Bahamian sample. These results indicate that the source of the Bahamian lionfish is egg and larval dispersal
from the United States east coast population, and support previous models of reef fish dispersal that suggest a low level
of connectivity between the Bahamas and east coast of Florida. 相似文献