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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Prehistoric caches in an intermittent wetlands environment : an analysis of the Nicolarsen Cave collection, Washoe County, Nevada /

Barnes, Robin Benson, January 2000 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 215-225). Available also in a digital version from Dissertation Abstracts.
42

Troublesome Children: Mormon Families, Race, and United States Westward Expansion, 1848-1893

Mayer, Eve 15 March 2013 (has links)
Debates over Mormons in the nineteenth century United States were rarely solely about Mormonism. This dissertation examines the ways in which Utah-oriented discourses of outsider groups influenced political debates at the local, regional, and national levels between 1848 and 1893. As recent studies by Sarah Barringer Gordon and Terryl Givens have shown, the conflicts around which these discourses developed pertained to Mormons and polygamy specifically, but also to broader questions of religious freedom, racial diversity, and the extent to which a community might operate autonomously within the United States. The dissertation expands on decades-old analyses of visual and literary representations of Mormons, considering intertextual dynamics and drawing on a broad source base including non-traditional artifacts such as government reports, objects, maps, and personal writing. My analysis of the changing attitudes towards and representations of Mormon settlement is informed by the growing historiographies of anti-polygamy, anti-Mormonism, and the relationship between gender, family and empire. Examining anti-polygamy discourse through the lens of settler colonialism offers a fresh perspective on the motives, anxieties, and priorities of United States policymakers seeking control of the resources and people of the Great Basin. I will argue that this analytical viewpoint, which has been used primarily in indigenous and subaltern studies, can also be meaningfully applied to a religious sect that was part of the racial majority. Exploring objections to Mormon settlement over time reveals the extent to which Mormon self-fashioning was seen as potentially destabilizing to Anglo-American categories of race and gender—and the profound implications of those categories in political and economic terms. Overall, my analysis reinforces the significance of monogamy as a means of maintaining political control and enforcing racial order. The resolution of the “Mormon Question” in favor of the prevailing kinship model contributed to gendered imperial practices of the United States in the subsequent period of overseas expansion. As a site of confrontation between United States expansionism and distinct social and cultural configurations, the Great Basin was a principal laboratory for the development and testing of issues of United States colonial policy prior to the Spanish-American War.
43

Amphibian Occurrence on South Okanagan Roadways: Investigating Movement Patterns, Crossing Hotspots, and Roadkill Mitigation Structure Use at the Landscape Scale

Crosby, Jonquil January 2014 (has links)
Road expansion and increased traffic likely exacerbates barriers to amphibian migration and dispersal. Within British Columbia’s south Okanagan valley there is particular concern that the COSEWIC-listed blotched tiger salamander (Ambystoma mavortium melanostictum) and Great Basin spadefoot (Spea intermontana) are vulnerable to road effects in their annual movements from upland overwintering habitat to lowland breeding areas. My study utilizes a before after control impact approach to assess amphibian movement and population threats across this highway-bisected landscape. Throughout the spring and summer of 2010-2012, fifty two kilometers of roadways (31 km of highway, 21 km of paved backroad) were repeatedly surveyed from the Canada-USA border to north of Oliver, BC; surveys were carried out utilising vehicles and on foot. Along Highway 97, a three kilometer four-lane highway expansion project was constructed through 2010 and open to traffic use in 2011. Adjacent to a floodplain, survey effort was focused throughout this transect for informed roadkill mitigation structure placement and ongoing ecopassage effectiveness monitoring. Automated camera trap monitoring of culverts within highly concentrated amphibian road hotspots during spring and summer 2011 (three culverts) and 2012 (two culverts) resulted in over eight hundred amphibian culvert events observed. Two sample Wilcoxon tests revealed differences between years in amphibian occurrence between 2010 and 2012 (W = 4679.5, p= 0.02), and mortalities among transect areas, with the largest differences between years within the Osoyoos passing lanes transect. Amphibian mortalities within the passing lanes transect were significantly reduced with the implementation of mitigation structures (x̅2010= 13.2 ± 32.5, x̅2011= 4.7 ± 12.8, x̅2012= 2.3 ± 7.3; 2010 vs. 2012: W= 1535.5, p< 0.001). Roadkill mitigation structures proved effective in observed amphibian occurrence of the entire passing lanes stretch as well as at distances 100 m and 200 m from observed culverts. Double fenced areas resulted in a 94% reduction in amphibian road occurrence. Five species of amphibians were observed over the three survey years (4051 road incidences over 657 survey hours): Pacific chorus frog (Pseudacris regilla), Western toad (Anaxyrus boreas), long-toed salamander (Ambystoma macrodactylum) plus blotched tiger salamander and Great Basin spadefoot. This study aims to provide a better understanding of amphibian hotspots on roadways and ecopassage use within the south Okanagan. It may act as a catalyst to further wildlife-vehicle interaction studies with improved mitigation solutions for amphibian roadway fatalities.
44

Climatic change and water supply in the Great Basin

Flaschka, Irmgard Monika. January 1984 (has links) (PDF)
Thesis (M.S. - Hydrology and Water Resources)--University of Arizona, 1984. / Includes bibliographical references (leaves 71-75).
45

Geology of the north Muddy Mountains, Clark County, Nevada and regional structural synthesis : fold-thrust and basin-range structure in southern Nevada, southwest Utah, and northwest Arizona /

Carpenter, Daniel G. January 1989 (has links)
Thesis (M. Sc.)--Oregon State University, 1989. / Plates were folded and placed in a pocket. Includes bibliographical references (leaves 128-140). Also available on the World Wide Web.
46

Structure of the southern Mormon Mountains, Clark County, Nevada and regional structural synthesis : fold-thrust and basin-range structure in southern Nevada, southwest Utah, and northwest Arizona /

Carpenter, James A. January 1989 (has links)
Thesis (M. Sc.)--Oregon State University, 1989. / Plates were folded and placed in a pocket. Includes bibliographical references (leaves 126-133). Also available on the World Wide Web.
47

Parowan pottery and Fremont complexity : late formative ceramic production and exchange /

Watkins, Christopher N., January 2006 (has links) (PDF)
Thesis (M.A.)--Brigham Young University. Dept. of Anthropology, 2006. / Includes bibliographical references (p. 118-136).
48

Parowan pottery and Fremont complexity late formative ceramic production and exchange /

Watkins, Christopher N., January 2006 (has links) (PDF)
Thesis (M.A.)--Brigham Young University. Dept. of Anthropology, 2006. / Includes bibliographical references (p. 118-136).
49

The Responses of Ants and Other Invertebrates to Fire and Rodent Activity in North American Deserts

Day, Joshua David 01 August 2018 (has links)
Human activities are increasing the size, frequency and severity of disturbance across earth’s ecosystems including deserts. Exotic annual grasses have altered fire regimes by increasing the size, frequency, and severity of fires in these systems. Invertebrates make up a large proportion of ecosystem diversity, provide a wide range of ecosystem functions, and are good indicators of ecosystem function and resilience. Ants are particularly good indicators of ecosystem stability. The ability of rodents to modify plant community structure post-fire, could result in rodent communities having important indirect effects on invertebrate communities. In chapter 1 we report changes in ant forager abundance and diversity with fire and rodent treatments over a three year period in the Great Basin. We found that while rodents had significant effects on the plant community in burned plots, this did not affect the ant community. Fire, however played a significant role in determining ant species richness and Shannon’s diversity index. Ant richness and diversity were reduced in burned areas compared to unburned areas. Total ant forager abundance was unaffected by fire, however, the abundance of the most common ant species, Pogonomyrmex occidentalis, increased in burned areas. The overall abundance of the other species was reduced in burned areas. We saw increases in the densities of P. occidentalis mounds in burned areas, but the average size of those discs decreased. The total area occupied by P. occidentalis mounds remained equal between burned and unburned plots. In chapter 2 we compare the abundances of different groups of invertebrates, as well as the abundances and diversity of the ant communities, between fire and rodent treatments. We then compared how those responses differed between sites in the Great Basin and Mojave deserts. In this study, we found that the abundances of most invertebrate groups remained unaffected by fire and rodent treatments. In the Great Basin, however, the abundance of flying-foragers was reduced in burned areas. At both locations, ant species richness and Shannon’s diversity were reduced in burned areas. Species richness and Shannon’s diversity were negatively correlated with invasive plant cover at both sites, and invasive plant cover was positively correlated with fire. The loss of diversity can spell losses in important ecosystem functions, and invasive grass fire cycles threaten to make these losses permanent.
50

Assessment of Great Basin Bristlecone Pine (Pinus longaeva D.K. Bailey) Forest Communities Using Geospatial Technologies

Burchfield, David Richard 20 July 2021 (has links)
Great Basin bristlecone pine (Pinus longaeva D.K. Bailey) is a keystone species of the subalpine forest in the Great Basin and western Colorado Plateau ecoregions in Utah, Nevada, and California. Bristlecone pine is also the world's longest-lived non-clonal organism, with individuals occasionally reaching ages up to 5,000 years old. Because of its longevity, bristlecone pine contains an important proxy record of climate data in its growth rings. Despite its ecological and scientific importance, bristlecone pine's distribution and associated environmental drivers are poorly understood. Geospatial technologies, including unmanned aircraft systems (UAS), remote sensing, geographic information systems (GIS), and spatial modeling techniques can be used to quantify and characterize biotic and abiotic factors that constrain the fundamental and realized niches of bristlecone pine and other subalpine forest species. In Chapter 1, we describe workflows and important technical and logistical considerations for collecting aerial imagery in mountainous areas using small UAS, enabling high-quality remotely sensed datasets to be assembled to study the ecology of subalpine forests. In Chapter 2, we discuss a unique outlier population of bristlecone pine found in the Stansbury Mountains, Utah. We used GIS to delineate boundaries for five small stands of bristlecone pine and examined two competing hypotheses that could explain the species' presence in the range: 1) that the current population is a relict from the Pleistocene, or 2) that long-distance dispersal mechanisms led to bristlecone pine's migration from other mountain ranges during or after the warming period of the Pleistocene/Holocene transition. Potential migration routes and barriers to migration were considered in our effort to understand the dynamics behind the presence of this unique disjunct population of bristlecone pine. Chapter 3 describes a comprehensive mapping effort for bristlecone pine across its entire distribution. Using data from historic maps, vegetation surveys, herbarium records, and an online ecological database, we compiled nearly 500 individual map polygons in a public-facing online GIS database representing locations where bristlecone pine occurs. Using these occurrence data, we modeled the suitable habitat of the species with Maximum Entropy (MaxEnt), examining the relative importance of 60 environmental variables in constraining the species distribution. A probability map was generated for bristlecone pine, and the environmental variables were ranked in order of their predictive power in explaining the species distribution. We found that January mean dewpoint temperature and February precipitation explained over 80% of the species distribution according to the MaxEnt model, suggesting that the species favors drier air conditions and increased snowfall during winter months. These three studies demonstrate that geospatial tools can be effectively used to quantify and characterize the habitat of bristlecone pine, leading to improved management and conservation of the species in the face of multiple threats, including mountain pine beetle (MPB), white pine blister rust (WPBR), and possible habitat constriction due to climate change.

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