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- A core task of recreation research is to understand the relation between settings, scenery, and visitor experiences. This paper uses environmental psychology to describe four conceptual models underlying these relations: inherent/aesthetic, opportunity/goal-directed, symbolic, and expressive. The paper then describes some challenges to applying results to recreation resource management.AuthorsDaniel R. WilliamsKeywordsSourceIn: Kruger, Linda E.; Mazza, Rhonda; Lawrence, Kelly, eds. Proceedings: National workshop on recreation research and management. Gen. Tech. Rep. PNW-GTR-698. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station: 29-41Year2007
- Watersheds capture and deliver fresh water to streams, rivers, wetlands and lakes. They are fundamental landscape units for freshwater fisheries because they govern the characteristics of the annual hydrograph, the configuration and physical features of stream channels, and the input of organic matter and nutrients. Watersheds are also where we live, grow crops, and create various forms of industry, As the world's population grows, competition for water and the ecological goods and services that water provides grows more intense. Between 1900 and 1995, global consumption of fresh water...AuthorsPete Bisson, Timothy J. Beechie, George R. PessSourceAmerican Fisheries Society Symposium. 49: 1865-1880Year2007
- Chytridiomycosis (infection by the fungus Batrachochytrium dendrobatidis) is an emerging pathogen of amphibians that is associated with declines in at least four continents. We report results of disease screens from 271 field-sampled amphibians from Oregon and Washington. Chytridiomycosis was detected on 5 of 7 species and from 31 percent of all smaples, including sensitive species western toad (Bufo boreas), northern red-legged frog (Rana aurora), and Oregon spotted frog (R. pretiosa). We also detected chytridiomycosis in nonnative bullfrogs (R. catesbeiana) in western and central Oregon....AuthorsC.A. Pearl, E.L. Bull, D.E. Green, J. Bowerman, M.J. Adams, A. Hyatt, W.H. WenteKeywordsSourceJournal of Herpetology. 41(1): 145-149Year2007
- Place-related concepts are factors in public involvement, conflict, recreation management, recreation displacement, landscape planning and design. This has captured the attention of researchers and managers. We posit that planning and management of public lands requires an understanding of what it is about the lands that people value and care about. In this paper we discuss multiple uses of the term "place" and the various place-related concepts that have emerged, and how these concepts are used to inform public land planning and management.AuthorsLinda E. Kruger, Daniel R. WilliamsKeywordsSourceIn: Kruger, Linda E.; Mazza, Rhonda; Lawrence, Kelly, eds. Proceedings: National workshop on recreation research and management. Gen. Tech. Rep. PNW-GTR-698. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station: 83-88Year2007
- The work described in this report was initiated during the Interior Columbia Basin Ecosystem Management Project (ICBEMP). The ICBEMP produced a broad-scale scientific assessment of ecological, biophysical, social, and economic conditions for the interior Columbia River basin and portions of the Klamath and Great Basins. The broad-scale assessment made extensive use of potential vegetation (PV) information. This report (1) discusses certain concepts and terms as related to PV, (2) describes how a PV framework developed for the broad-scale ICBEMP assessment area was stepped down to the level...AuthorsDavid C. Powell, Charles G. Johnson, Elizabeth A. Crowe, Aaron Wells, David K. SwansonKeywordsSourceGen. Tech. Rep. PNW-GTR-709. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 87 pYear2007
- Mechanical harvesting and associated logging activities have the capacity to compact soil across large portions of harvest units. Two thinning treatments (felled only versus felled and skidded) in 70- to 80-year-old ponderosa pine stands were replicated at three sites with volcanic soils in central Oregon. Growth in diameter, height, and volume of residual trees were related to degree of soil compaction, measured as soil strength with a recording penetrometer. Felled and skidded plots had significantly higher soil strength values than felled-only plots (42 percent). Tree diameter, height,...AuthorsR.T. Parker, D.A. Maguire, D.D. Marshall, P. CochranKeywordsSourceWestern Journal of Applied Forestry. 22(2): 134-141Year2007
- We used spatial simulation models to evaluate how current and two alternative policies might affect potential biodiversity over 100 years in the Coast Ranges Physiographic Province of Oregon. This 2.3-million-ha province is characterized by a diversity of public and private forest owners, and a wide range of forest policy and management objectives. We evaluated habitat availability for seven focal species representing different life histories. We also examined how policies affected old-growth stand structure, age distributions relative to the historical range of variability, and landscape...AuthorsT.A. Spies, B.C. McComb, R. Kennedy, M.T. McGrath, K. Olsen, R.J. PabstKeywordsSourceEcological Applications. 17(1): 48-65Year2007
- 1. Deposition of nutrients owing to anthropogenic activities has the potential to change nutrient availability in nutrient-limited ecosystems with consequences for plant and ecosystem processes. 2. Species-specific and ecosystem responses to the addition of nutrients were studied in a field experiment conducted in a Savanna (Cerrado sensu stricto) on dystrophic soil in central Brazil. Three fertilization treatments (nitrogen [N], phosphorus [P], and N plus P additions) and unfertilized control were replicated in four 15- x 15-m plots per treatment. 3. Five of the dominant woody species...AuthorsA.R. Kozovits, M.M.C. Bustamante, C.R. Garofalo, S. Bucci, A.C. Franco, G. Goldstein, Frederick MeinzerSourceFunctional Ecology. 21: 1034-1043Year2007
- Silvicultural practices in the Douglas-fir region evolved through a combination of formal research, observation, and practical experience of forest managers and silviculturists, and changing economic and social factors. This process began more than a century ago and still continues. It has had a great influence on the economic well-being of the region and on the present characteristics of the region’s forests. This long history is unknown to most of the public, and much of it is unfamiliar to many natural resource specialists outside (and even within) the field of silviculture. We trace...AuthorsRobert O. Curtis, Dean S. DeBell, Richard E. Miller, Michael Newton, J. Bradley St. Clair, William I. SteinSourceGen. Tech. Rep. PNW-GTR-696. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 172 pYear2007
- In forests historically maintained by frequent fire, reintroducing fire after decades of exclusion often causes widespread overstory mortality. To better understand this phenomenon. we subjected 16 fire-excluded (ca. 40 years since fire) 10-ha longleaf pine (Pinus palustris Mill.) stands to one of four replicated burning treatments based on volumetric duff moisture content (VDMC): wet (115 percent VDMC): moist (85 percent VDMC); dry (55 percent VDMC); and a no-burn control. During the first 2 years postfire, overstory pines in the dry burns suffered the greatest mortality (mean 20.5...AuthorsJ.M. Varner, J.K. Hiers, Roger D. Ottmar, D.R. Gordon, F.E. Putz, D.D. WadeSourceCanadian Journal of Forest Research. 37: 1349-1358Year2007