A continental-scale study of historic wildfire data within and across ecoregion provinces was conducted and geographical gradients in seasonal measures of wildfire size and frequency were observed. In the conterminous United States, western ecoregion provinces show north-south gradients in duration of season (short-to-long) and peak of season (early-to-late). Across the continent a gradient of unimodal to bimodal seasonal distributions of wildfire size and frequency was shown: western ecoregions have a single summer fire season and eastern regions have spring and late-summer fire seasons separated by an intervening dip in wildfire activity. From the ecoregion provinces with the highest wildfire frequency, average size, and area burned values, eight federal land units (four from the western and four from the eastern conterminous United States) were selected for a study of geographical variation in interactions between wildfire variables and the Keetch-Byram Drought Index (KBDI). Daily KBDI values for each location were provided by the North American Land Data Assimilation System (NLDAS). Confidence intervals around the mean for both days on which wildfires ignited and for days on which no new wildfires ignited were generated for each location using a bootstrap resampling method. A greater difference existed between nonire and fire-start KBDI values in the western locations, indicating a stronger association between KBDI and wildfire potential. At eastern locations, the difference between mean nonire and fire-start KBDI was lower than the minimum western mean difference for three of the four locations. The exception, the Great Dismal Swamp National Wildlife Refuge, showed the second highest difference between nonire and fire-start KBDI values of all eight federal land units. These results indicate that across the southeastern United States, the soil moisture (and, by extension, fuel moisture) cycle from field capacity (saturation) to drought (wilting point) and back to field capacity does not follow the regular seasonal pattern shown in the western states, and neither do geographical characteristics of wildfires.

No description available.

Thesis (M.S.)--University of Montana, 2006. / Title from PDF t.p. (viewed on Mar. 14, 2007). Includes bibliographical references (p. 112-117).

Thesis (Ph. D.)--University of Oregon, 2003. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 453-468). Also available for download via the World Wide Web; free to University of Oregon users.

No description available.

Thesis (M.S.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 117-124). Also available on the World Wide Web.

The battle over federal Wilderness designation of Bureau of Land Management lands in southern Utah has entered its third decade. Throughout this lengthy debate numerous stakeholders have maintained involvement, including members of Utah's conservation community. Two of the most prominent wilderness advocacy groups in Utah are notable not only for their sustained involvement with the issue, but also for their divergent positions on how to resolve this public land dispute. This research examines those two organizations, the Utah Wilderness Association and the Southern Utah Wilderness Alliance, through an analysis of their respective structural, organizational, philosophical, and tactical perspectives. Ultimately, the background of each organization's leadership, their organizational structures, their ability to mobilize resources, and their distinctive wilderness philosophies offer an understanding of how each organization perceived its mission and its ability to provide a construct for resolution of the Utah Wilderness debate.

Social contact norms are used by managers to establish standards for regulating visitation of wilderness areas so that visitors can attain adequate experiences of solitude. This study expanded on current conceptions of social contact norms to provide a theoretical and empirical basis for understanding how such norms are formed. Using person perception, stereotyping, and socialization theory and the concept of cognitive schemata, a conceptual framework was built to explain how visitors come to judge certain groups as appropriate or inappropriate in a wilderness area. Seven research hypotheses were proposed and tested using a database consisting of responses to a mail questionnaire survey of 800 permit requestors and 95 interviews with visitors at Aravaipa Canyon Wilderness, Arizona. The first hypothesis, that wilderness visitors would regard some types of groups as appropriate and other types of groups as inappropriate in the wilderness area, was supported. Norms for encountering 13 types of groups were estimated from written questions and drawings, and paired picture comparisons allowed ranking of six types of groups. Encounters with lone hikers, small groups, medium-sized groups, birdwatchers, youth groups, school classes, and rangers were considered more appropriate than encounters with hunters, horseback riders, packstock users, and nude bathers. Logit and multinomial logit models were used to test the six remaining hypotheses, which concerned the influences of socialization and other processes on development of social contact norms. To test the hypotheses, norms for encountering six types for groups were predicted from demographic and other variables. The results indicated that norms for encountering small groups were not affected by social class or race; affiliation with a small group during a wilderness visit was associated with a dislike of large groups, membership in a conservation organization had no such association; members of conservation organizations preferred fewer encounters with hunters; membership in a conservation organization also prompted the respondents to dislike encounters with horseback riders; females, older visitors, and people with children disliked encountering nude bathers; and inexperienced and less self-reliant visitors enjoyed encounters with rangers. Theoretical, managerial, and social implications of these results were then discussed.

Throughout its eruptive history, Mount Hood has produced compositionally similar calc-alkaline andesite as lava flows and domes near the summit and basaltic andesitic flows from flank vents. Found within the andesite are slightly more mafic inclusions that are compositionally similar to the host andesite (or host lavas); no inclusions were found in the flank lavas. Host lavas and inclusions have the following mineral assemblage: plag + opx ± cpx ± amp + oxides. Flank lava mineralogy is similar to the inclusions and host lavas, but since they are more mafic they contain olivine instead of amphibole. Average silica content among samples analyzed ranges from 57.6 to 62.7 weight percent; however the incompatible trace element composition is more variable at lower silica contents and becomes less variable at higher silica contents. In terms of incompatible trace element composition, the host lavas and inclusions are either depleted (no amp) or enriched (amp± cpx).

Includes the full and summary reports of State of the Tasmanian Wilderness World Heritage Area: an evaluation of management effectiveness. / Title from home page (viewed on June 9, 2005). Full report also issued in print and CD.