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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.
1

Phylogeographic Patterns and Intervarietal Relationships within Lupinus lepidus: Morphological Differences, Genetic Similarities

Weitemier, Kevin Allen 01 January 2010 (has links)
Lupinus lepidus (Fabaceae) contains many morphologically divergent varieties and was restricted in its range during the last period of glaciation. A combination of phylogenetic (with the trnDT and LEGCYC1A loci) and population genetics approaches (with microsatellites and LEGCYC1A are used here to characterize intervarietal relationships and examine hypotheses of recolonization of areas in the Pacific Northwest affected by glaciation. Sequenced loci are not found to form a clade exclusive to L. lepidus, nor are any of the varieties found to form clades. Population genetics analyses reveal only negligible genetic structure within L. lepidus, with the majority of variation being found within populations. Isolation-by-distance analysis reveals some correlation between population genetic distances and geographic distance. Microsatellite and sequence results are consistent with a scenario whereby the Oregon and Washington regions were rapidly colonized from the south, with independent invasions along the eastern and western sides of the Cascade Mountains. A predicted disjunction between northern and southern populations is found within the microsatellite data but not the sequence data, suggesting that northern populations were recolonized via a process involving the spread of novel microsatellite mutations, perhaps through the persistence of a glacial refuge isolated from southern populations. Varieties are not shown to be genetically isolated, and are interpreted as representing ecotypes, with local selection outpacing the effects of migration.
2

The Recognition, Investigation, Interpretation, and Treatment of Landslides in the Pacific Northwest

Ludowise, Harry 01 January 1974 (has links)
Certain features unique to the Pacific Northwest influence landsliding in this region. Weakly consolidated sediments, dense vegetation and seasonally concentrated rainfall all contribute to the distinctive conditions that are encountered here. This study gathers together information applying to the recognition and correction of Pacific Northwest landslides. Treatment practices common to this region are discussed. A large slide located about 30 miles east of Portland, Oregon along the Clackamas River is used as an example. Exploration, instrumentation, analysis and corrective measures are illustrated.
3

William Hobson and the founding of Quakerism in the Pacific Northwest

Goldsmith, Myron Dee January 1962 (has links)
Thesis (Ph.D.)--Boston University / William Hobson (1820-1891) joined the ante bellum exodus of Quakers from North Carolina, migrating to Iowa in his late youth where he served as a pioneer minister of Friends until 1875. He then began the formation of a settlement of Quakers at Newberg, Oregon, which grew rapidly and eventually resulted in the establishment of Oregon Yearly Meeting of Friends. Because so little was known of the early life of William Hobson, and because nineteenth century revivalism radically altered the Quakerism of Hobson's lifetime, he is not well understood by contemporary Friends. This dissertation therefore attempts to describe his early years and ministry and their relation to trends within American Quakerism, and to estimate his significance as the founder of Quakerism in the Pacific Northwest. The study is based on Hobson's autobiography, his diaries and sources of information not previously considered. These latter are his correspondence and personal papers, the journals of his Quaker contemporaries, public documents, school records and the official minutes of Friends Meetings to which he belonged in North Carolina, Iowa and Oregon. The new sources have made possible a biographical synthesis which presents William Hobson in a truer perspective than he has heretofore been seen. William Hobson was reared in the back-country of North Carolina under the strict standards of the Society of Friends. Educational opportunities and literature were both very limited, and arter learning to read, he had little save the Scriptures and standard works or Quakerism to study. These, in addition to two years at New Garden Boarding School, confirmed him in the beliers and customs of his ancestors. Attracted by the agricultural prospects or the Trans-Mississippi Vest and moved by a hatred or slavery, he migrated to Iowa in 1847-1848. Throughout the third quarter or the nineteenth century Hobson was a pioneer farmer and minister of Friends, journeying throughout the Friends settlements or Iowa, to North Carolina and to Kansas during the troubled days or border warfare. As an itinerant minister of Friends, his work was carried on in the quietistic spirit typical of early nineteenth century Quakerism. He welcomed the evidences of new life which came to Quakerism with the Awakening of the 1860's and 1870's, but regretted and resisted the innovations which revivalism produced. Hobson made the first of his three journeys to the Far West in 1870-1871, spending seven months surveying the Pacific Coast in the interest of establishing a Quaker settlement. Discouragement led him to conclude that Friends should stay in the Midwest, but within two years his mind was again occupied with the need for a Friends community on the Pacific Coast. In 1875-1876 he made a second journey, determined to overcome all obstacles to his projected settlement. After studying six regions in Oregon and in Washington Territory, he eventually chose the Chehalem Valley, near Portland, Oregon. As a result of his enthusiastic correspondence with Quakers throughout the Far West and Midwest, settlers began pouring into the valley, and by the time of his death in 1891, the membership of Newberg Meeting was over five hundred. William Hobson was well qualified to establish a frontier religious settlement due to his rugged physique and lifetime of experience under frontier conditions. He had a keen awareness of the material basis of a happy society, and carefully studied the resources of the Pacific Northwest before founding a settlement. Possessing the sense of community normative to Quakerism, he frankly advertised the settlement as a religious community and made it succeed as such without limiting it to Friends. The permanent value of his work is indicated in the Quaker institutions of Church, school and civil order which developed in the Chehalem Valley and which became influential throughout the Pacific Northwest.
4

Potential for Speciation in Mammals Following Vast, Late Miocene Volcanic Interruptions in the Pacific Northwest

McKenna, Ryan Thomas 01 January 2011 (has links)
The impact of large-scale volcanic eruptions on landscapes can affect many processes ranging from interrupting or redirecting regional soil forming processes and hydrological systems to generating temporary changes in global climate. Though more studies exist every year, less is known of the direct impact of large-scale volcanic eruptions on ecosystems and extinction, while even less is known of their impact on speciation. In deposits throughout the Pacific Northwest a special combination and association of volcanic magnitude with palaeoecological yield frequently presents unique prospects for inquiry. In this study, particular attention is given to large, late Miocene ash-flow tuffs of central and eastern Oregon, the Rattlesnake Tuff among them. Additionally, a scenario is tested whereby populations become isolated from one another across the expanse of ash-flow tuff and enclosed by nearby physical barriers. Exploration into this scenario and the effects of ecological recovery on speciation in mammals are made through a cellular automaton created here and speciation modeling by H.A. Orr. The cellular automaton is validated by a small data set from New Zealand with results of all models compared to studies in ecology, the fossil record, genetics, and island evolution. Results suggest ecosystem recovery is much faster than mammalian species origination rates. Though evolution in mammals is known to occur over relatively short intervals of time (10 - 10 yrs), based on model comparisons, primary productivity generally returns to its carrying capacity two orders of magnitude (10 - 10 vs. ≥ 10 yrs) faster than mammalian speciation.
5

Propagule Pressure and Disturbance Drive the Spread of an Invasive Grass, Brachypodium sylvaticum

Taylor, Laura Alayna 01 January 2011 (has links)
The invasibility, or susceptibility of an ecosystem to biological invasion is influenced by changes in biotic and abiotic resistance often due to shifts in disturbance regime. The magnitude of invasive propagule pressure interacts with an ecosystem's invasibility to determine the extent of a biological invasion. I examined how propagule pressure, forest community structure and disturbance interact to influence the invasibility of temperate Pacific Northwest forests by the newly-invasive grass, Brachypodium sylvaticum. My goal was to identify which of these factors is most instrumental in enabling the shift from establishment to population growth in B. sylvaticum at the edge of its expanding range. Both observational and experimental studies were employed to identify the many ecological components of this problem. Ecological sampling methods were used to identify trends in B. sylvaticum habitat preference and signs of habitat disturbance. In addition, an experimental study was performed to test the effects of soil and vegetation disturbance on B. sylvaticum seedling propagation. I found that while soil disturbance did not have a significant effect on seedling propagation, vegetation disturbance was implicated in B. sylvaticum spread. Higher propagule pressure and coniferous forest type were also strong predictors of increased B. sylvaticum seedling propagation and survival within established sites. My study demonstrates how propagule pressure and plant community dynamics interact to shift the invasibility of Pacific Northwest forests and facilitate the transition from establishment to spread in the invasion of B. sylvaticum.
6

Subsistence variability on the Columbia Plateau

Atwell, Ricky Gilmer 01 January 1989 (has links)
Long-term human dietary change is a poorly understood aspect of Columbia Plateau prehistory. Faunal assemblages from thirty-four archaeological sites on the Plateau are organized into fifteen aggregate assemblages that are defined spatially and temporally. These assemblages are examined in terms of a focal-diffuse model using ecological measures of diversity, richness and evenness. Variability and patterning in the prehistoric subsistence record is indicated. Major trends in human diet and shifts in subsistence economies are documented and the relationship between subsistence and some initial semi-sedentary adaptations on the Plateau is clarified.
7

Status of Nutria (Myocastor coypus) Populations in the Pacific Northwest and Development of Associated Control and Management Strategies, with an Emphasis on Metropolitan Habitats

Sheffels, Trevor Robert 07 March 2013 (has links)
The nutria (Myocastor coypus) is a semi-aquatic rodent native to South America that was introduced to the Pacific Northwest, USA, in the 1930s. Primary damage categories from this invasive species include burrowing and herbivory, resulting in habitat degradation. Nutria have become well-established in metropolitan habitats, and anecdotal information suggests the problem has increased in recent years. However, little regional research on the species has been conducted. The scope of this research, which emphasizes metropolitan habitats, includes three primary foci in relation to nutria populations in the Pacific Northwest: modeling habitat suitability, assessing activity and movement patterns, and identifying and managing negative impacts. Large-scale management of any invasive species requires understanding of the current and potential future population distribution. Cold temperatures have been assumed to be a limiting factor for the geographic distribution of nutria populations, but this assumption had not been explicitly tested. A mechanistic habitat suitability model based on winter temperatures performed well in predicting nutria distribution in the Pacific Northwest and nationally. Regional results suggest nutria currently occupy most accessible suitable habitat. However, coupling the model with future climate change data suggests a much larger suitable habitat zone regionally and nationally in the near future. Management of an invasive species on a local scale requires region-specific information about behavior patterns. Radio-telemetry tracking of local nutria populations in metropolitan habitats suggested higher diurnal activity levels than reported elsewhere. Activity areas were also on the lower end of reported nutria home ranges, suggesting the studied metropolitan wetland sites represent core habitat for nutria in the region. Comparison of two transmitter attachment methods, a neck collar and a tail mount, did not identify a clearly superior attachment method for short-term nutria behavior studies. The presence of nutria in metropolitan habitats in the Pacific Northwest necessitates the need to expand the limited management techniques available for these habitats. Standard Vexar® plastic mesh tubes very effectively mitigated nutria herbivory damage to woody vegetation live stakes planted in a metropolitan habitat restoration site. A recently developed nutria multiple-capture cage trap captured larger nutria and reduced non-target captures compared to a standard cage trap. The design of the multiple-capture trap, however, prevented multiple-capture events because small nutria escaped the trap. This research contributes substantially to previously limited information about nutria in the Pacific Northwest and resulted in several new findings. Climate change modeling provides the first evidence that nutria ranges could expand in the near future. Evaluation of new radio-telemetry methods will benefit future behavior studies. The assessment of new damage prevention tools provides more options for the management of nutria in urban habitats. Management recommendations include creating regional nutria management plans, identifying and targeting priority monitoring regions, finding key stakeholders, focusing on public education, and initiating a pilot control program. Recommendations for research include evaluating effects on native fauna, conducting disease surveys, assessing the extent of damage, continuing habitat suitability analysis, and developing population indices.
8

Ancient Cataclysmic Floods in the Pacific Northwest: Ancestors to the Missoula Floods

Medley, Erica 05 January 2012 (has links)
Ancient Cataclysmic Floods were the Ice Age Floods that left erosional and depositional features and preceded the Missoula Floods (15-18,000 ka) in the Pacific Northwest of the United States (Allen et al., 2009). All previously studied ancient sites were visited (14) and new sites (11) were found; four Missoula Flood quarries were also visited; a total of 29 sites were studied in this thesis. The use of calcrete paleosols to provide relative age dates for flood deposits was analyzed in this thesis. Missoula Flood gravel pits were sampled in order to examine the degree of calcrete development in flood deposits of known ages. All of the Missoula Flood deposits tested contain Stage 1 calcrete soil development. Calcrete paleosols at sites with evidence for older floods were all analyzed. Eight sites have paleosols with Stage II development (3-12% CaCO3): Rulo Outcrop, Potholes Coulee, Leslie Road, Benge, E. Callaway Road, Collier Coulee, Palouse, and Connell. Five sites have paleosols with Stage II+ development (12-17% CaCO3): Brown Road, Leslie Road, Benge, Reese Coulee, and Connell. Fourteen sites have paleosols with Stage III development (17-35% CaCO3): The Dalles, Rulo Outcrop, Winans Road 1, Poplar Heights, Yakima Bluffs, Canal Outcrop, Othello Canal, Reese Coulee, Potholes Coulee, E. Callaway Road, Frenchmen Coulee, Macall, Ritzville, and East Connell. One site has a paleosol with Stage III+ development (35-50% CaCO3): Othello Canal. Ancient Cataclysmic flooding initiated in the Early Pleistocene, at least 1.5 Ma. Sixteen field sites show evidence for Early Pleistocene flooding, preserved in all six provinces: Othello Channels, Columbia River Gorge, Cheney-Palouse Scabland, Quincy Basin, Pasco Basin, and the Walla Walla Valley. There are 26 field sites with evidence for Middle Pleistocene flooding, present in all regions except Othello Channels. Eleven of those 26 sites also show evidence for Early Pleistocene floods. Evidence for Early and Middle Pleistocene floods is present over a wide distribution of elevations from 117 to 524 meters.
9

Phylogeography of Two Species of the Genus Apochthonius Chamberlin, 1929, in the Pacific Northwest (Arachnida, Pseudoscorpiones)

Welch, Brandi Lynn 09 February 2016 (has links)
I used mitochondrial COI sequence data from forty one individuals to investigate phylogenetic relationships among populations of two morphologically similar species of the pseudoscorpion genus Apochthonius, A. minimus and A. occidentalis, in western Washington, Oregon, and northern California. My goal was to assess whether genetic structure in the two species was congruent with geography. Many plant and animal species in the Pacific Northwestern United States have shown patterns of genetic differentiation that follow both north-south and east-west trends, indicating that geologic and climatic events in the past separated populations to the extent that they became genetically differentiated. A distinct geographic pattern emerged within A. occidentalis, with at least one northern and two southern populations. A clade containing all A. minimus sequences was recovered. However, this clade falls within the larger clade of A. occidentalis, rendering A. occidentalis paraphyletic. Furthermore, the A. minimus sequences showed north-south geographic structuring within the clade. Population genetic analyses were performed based on geographic location within the Pacific Northwest. I found high genetic differentiation coupled with low gene flow between most populations, with the exception of the Portland and North Coast Range populations. These data suggest the presence of more than two species of Apochthonius in the Pacific Northwest.
10

Examining Human Behavior and Tool Use through Experimental Replications and a Technological Analysis of Ground Stone in the Lower Columbia

Martinez, Kelley Prince 17 May 2019 (has links)
While ground stone tools represent diverse activities, the technology is analyzed at a coarse level in the Pacific Northwest. Conducting more detailed analyses of ground stone assemblages can inform on regional Indigenous raw material knowledge, resource use, and tool manufacturing and maintenance practices. In this thesis I addressed questions regarding ground stone technology, including manufacturing time investments, tool recycling, and how ground stone tools were used through the application of experimental tool replication, use studies, and in depth analyses. I replicated tools that are common in the region, including a banded and notched net weight, a maul, two bowls, and a pestle. The replicated tools were all produced with raw materials collected from nearby sources and all ground stone tools were manufactured with cobble choppers. I conducted use wear studies in two phases to examine the impacts of processing both hard and soft materials using the replicated bowl and pestle. The tools underwent an in-depth analysis before and after manufacture and the use wear study to assess manufacturing and use wear attributes. The experimental replications and use study resulted in associating specific attributes with known activities and actions. These insights were then applied to the analysis of ground stone artifacts from the 35CO2 Rylander assemblage, a private artifact collection from a contact-period archaeological site located in the Lower Columbia. I was able to identify manufacturing and use wear attributes to further explore how the ground stone tools were manufactured, used, and maintained. Additionally, I demonstrated a strong relationship between raw material selection, time investment, and tool recycling in the region through the experimental studies and comparative analysis with the Rylander assemblage. Furthermore, this study highlights the need for more robust ground stone analysis standards. Analyses that include in-depth examination at the attribute level will help expand our understanding of ground stone tool technology. Employing standardized vocabulary, terminology, and referencing attributes in photomicrographs builds more comparable datasets, giving researchers valuable insights into skill level, specialization, and time investment associated with ground stone technology.

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