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- Lands designated by Congress under the Wilderness Act of 1964 (Public Law 88-577) offer unique opportunities for social and biophysical research in areas that are relatively unmodified by modern human actions. Wilderness designation also imposes a unique set of constraints on the methods that may be used or permitted to conduct this research. For example, legislated restrictions on mechanical transport potentially make access difficult in large and remote wildernesses, while restrictions on motorized equipment and installations may prevent use of certain tools, data loggers, standard...AuthorsPeter B. Landres, Judy Alderson, David ParsonsKeywordsSourceGeorge Wright forum. 20(3): 42-49Year2003
- The Limits of Acceptable Change (LAC) and other indicator-based planning frameworks (e.g., VERP, Visitor Experience and Resource Protection; VIM, Visitor Impact Management) have been widely adopted by wilderness managers. A central feature of these frameworks is the selection of indicators of conditions that influence experience quality, and which managers can efficiently monitor.However, identifying meaningful influences on visitor experience quality and selecting appropriate indicators remains a persistent challenge. Managers often have little knowledge of which indicators are most...AuthorsBrian Glaspell, Alan E. Watson, Katie Kneeshaw, Don PendergrastKeywordsSourceGeorge Wright Forum. 20(3): 59-71Year2003
- White pine blister rust, Cronartium ribicola, has plagued the forests of North America for almost a century. Over past decades, eastern white pine (Pinus strobus) that appear to tolerate the disease have been selected and incorporated into breeding programs. Seeds from P. strobus with putative resistance were collected from Oconto River Seed Orchard, Nicolet National Forest, WI. Seedlings were grown for 5 months and artificially inoculated with basidiospores of C. ribicola in two replicated greenhouse experiments. Needles from infected seedlings were fixed, sectioned, and stained with a...AuthorsJoel A. Jurgens, Robert A. Blanchette, Paul J. Zambino, Andrew DavidSourcePlant disease. 87(9): 1026-1030Year2003
- A major challenge facing conservation biologists and wildlife managers is to predict how fauna will respond to habitat loss. Different species require different amounts of habitat for population persistence, and species’ reproductive rates have been identified as one of the major factors affecting these habitat-amount requirements. The purpose of this study was to test the prediction that species with higher reproductive rates require less habitat for population persistence than species with lower reproductive rates. We used 41 species of forest breeding birds to test for a relationship...AuthorsMelissa D. Vance, Lenore Fahrig, Curtis H. FlatherKeywordsSourceEcology. 84(10): 2643-2653Year2003
- Methods for restoring native plant communities on acidic mine spoils at high elevations were evaluated in a "demonstration area" in the New World Mining District of southern Montana. Research plots installed in 1976 were assessed for 22 years and compared with adjacent native reference plant communities. A 1.5-acre (0.61-ha) area of mine spoils was shaped and treated with hydrated lime, organic matter, and fertilizer. The area was then seeded heavily with five native grasses collected from adjacent native plant communities. Natural seed rain, transplanting, refertilization, and use of...AuthorsRay W. Brown, Michael C. Amacher, Walter F. Mueggler, Janice Kotuby-AmacherKeywordsSourceRMRS-RP-41. Ogden, UT: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. 49 p.Year2003
- Vegetative characteristics of swift fox (Vulpes velox) denning and foraging habitats were studied in southwestern South Dakota. We followed 14 radio-collared foxes over a two-year period and identified 17 den sites and 82 foraging sites. Height-density of vegetation (visual obstruction reading, VOR) was determined on each den and foraging site and on 81 randomly selected sites. Total vegetation VOR was higher (p=0.08) at den sites than on randomly selected sites (11.7±1.4 and 9.5±0.6cm (SE), respectively). Swift foxes used foraging areas with vegetation greater VOR (p=0.01) than that found...AuthorsDaniel Uresk, Kieth E. Severson, Jody JaversakKeywordsSourceResearch Paper RMRS-RP-38. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. 4 p.Year2003
- The ratio of leaf to sapwood area generally decreases with tree size, presumably to moderate hydraulic costs of tree height. This study assessed consequences of tree size and leaf area on water flux in Quercus garryana Dougl. ex. Hook (Oregon White Oak), a species in which leaf to sapwood area ratio increases with tree size. We tested hypotheses that Q. garryana individuals of greater size and leaf area show reduced leafspecific hydraulic conductance, crown water flux per leaf area, and carbon isotope discrimination.AuthorsN. Phillips, B. J. Bond, N. G. McDowell, Michael G. Ryan, A. SchauerKeywordsSourceFunctional Ecology. Vol. 17, no. 6 (Dec. 2003). p. 832-840.Year2003
- Metapopulation dynamics have emerged as a key consideration in conservation planning for salmonid fishes. Implicit to many models of spatially structured populations is a degree of synchrony, or correlation, among populations. We used a spatially and temporally extensive database of chinook salmon (Oncorhynchus tshawytscha) redd counts from a wilderness area in central Idaho to examine patterns in synchrony as these fish underwent a sixfold decrease in abundance. Our results suggested that populations became strongly synchronous as abundances decreased and that the range, or diversity of...AuthorsDaniel J. Isaak, Russ F. Thurow, B. E. Rieman, J. B. DunhamSourceCanadian Journal of Fisheries and Aquatic Sciences. 60: 840-848.Year2003
- We have conducted surveys of gullies that developed in a small, steep watershed in the Idaho Batholith after a severe wildfire followed by intense precipitation. We measured gully length and cross sections to estimate the volumes of sediment loss due to gully formation. These volume estimates are assumed to provide an estimate of sediment transport capacity at each survey cross section from the single gully-forming thunderstorm. Sediment transport models commonly relate transport capacity to overland flow shear stress, which is related to runoff rate, slope, and drainage area. We have...AuthorsErkan Istanbulluoglu, David G. Tarboton, Robert T. Pack, Charles H. LuceKeywordsSourceWater Resources Research. 39(4): 1103-1117.Year2003
- Over-estimation of willingness to pay in contingent markets has been attributed largely to hypothetical bias. One promising approach for avoiding hypothetical bias is to tell respondents enough about such bias that they self-correct for it. A script designed for this purpose by Cummings and Taylor was used in hypothetical referenda that differed in payment amount. In comparisons with behavior observed in otherwise identical real payment referenda, the script worked remarkably well at higher payment levels (dropping the likelihood of a yes vote to the level obtained in separate sample real...AuthorsThomas C. Brown, Icek Ajzen, Daniel HrubesKeywordsSourceJournal of environmental economics and management. 46(2): 353-361Year2003