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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.
541

Divergent anti-predator strategies and risk allocation in juveniles of three North Pacific flatfishes /

Boersma, Kate S. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 57-62). Also available on the World Wide Web.
542

Pacific Islands forum : facilitating regional security cooperation : a thesis submitted in fulfilment of the requirements for the degree of Master of Arts in Political Science in the University of Canterbury /

Boxall, Sheryl. January 2006 (has links)
Thesis (M.A.)--University of Canterbury, 2006. / Typescript (photocopy). Includes bibliographical references (leaves 222-233). Also available via the World Wide Web.
543

Vancouver service exports to the Asia Pacific and the role of local government in their promotion

Tate, Laura Ellen January 1991 (has links)
This thesis looks at the feasibility of promoting knowledge intensive service (KIS) exports to Asia as part of a local economic development strategy. To this end a two part study was conducted, consisting of a postal survey and a series of elite interviews. The study demonstrates that many Vancouver KIS firms have already established a presence in Pacific Rim markets; furthermore, future growth in these markets is likely. The study examines various characteristics of KIS exporters to Asia so as to enable policy makers to draft appropriate recommendations. The remainder of the thesis outlines current initiatives at senior and local levels of government. A case is made for increasing the scope of local government action in this sphere, and some potential initiatives are suggested. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate
544

A comparison of satellite winds and surface buoy winds

Bepple, Nancy January 1990 (has links)
This thesis investigates the relationship between open hexagonal cell cloud motion and surface winds in the northeast Pacific Ocean. Cloud targets are tracked using an automatic scheme fashioned after Barnea and Silverman's (1972) Sequential Similarity Detection Algorithm. The cloud motion vectors obtained are comparable to results obtained by tracking the same cloud targets manually. The well-organized character of open hexagonal cells permits a comparison of various methods of estimating the height of the cloud motion vectors. One method, which uses the minimum infrared pixel value, and a second method, which establishes an arbitrary minimum cloud top temperature, are both found to be unsuitable because of cirrus contamination and partially cloud filled pixels. The cloud motion winds for open hexagonal cells and disorganized cumulus clouds are compared with winds measured at collocated surface buoys. The lack of directional shears between open hexagonal cell movements and surface winds, and directional shears of 14° to 27° for the disorganized cumulus clouds, agree with other observations for the two types of clouds. The differences between the two cloud types suggests that any estimate of surface winds from cloud motion should include cloud type information. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
545

Major and trace element geochemistry of basalts from the Explorer area, Northeast Pacific Ocean

Cousens, Brian Lloyd January 1982 (has links)
Fifty fragments of young, fresh basalts from the Explorer Ridge, Paul Revere Ridge (Fracture Zone), Dellwood Knolls, and the J. Tuzo Wilson Knolls have been analysed for 12 major and minor elements, as well as 11 trace elements, by X-ray fluorescence spectrometry. Rare earth element concentrations in 25 of the samples have been determined by instrumental neutron activation, and Sr⁸⁷/Sr⁸⁶ ratios have been obtained for 11 of the basalts. The Explorer Ridge basalts have major element compositions similar to most mid-ocean ridge basalts (MORB), and can be classified as ferrobasalts, similar to those of the southern Juan de Fuca Ridge. The incompatible minor and trace elements K, Ti, Rb, Zr, and Nb are weakly to strongly enriched in the Explorer samples, with respect to MORB, part of which is the result of crystal fractionation. The observed trace element and light rare earth element (LREE) enrichment of many of the samples, particularly those from Explorer Deep, suggest that a weak hotspot may exist beneath the Explorer Deep. The adjacent ridge segments, Explorer Rift and the Southern Explorer Ridge, are erupting basalts both enriched and depleted in incompatible elements, which could be an indicator of a chemically heterogenous mantle source, or may be the result of intermittent injection of enriched magmas from the postulated hotspot beneath Explorer Deep into areas producing normal MORB. The enriched basalts do not have significantly different Sr⁸⁷/Sr⁸⁶ ratios from the depleted basalts. All the samples fall within the range of values typical for Juan de Fuca and Gorda Ridge basalts, and East Pacific Rise tholeiites in general. Thus, although the source areas for the 2 basalt types may differ chemically, they are similar radiogenically, unlike-other hypothetically plume-influenced areas such as the Mid-Atlantic Ridge at 45°N and the FAMOUS area. The basalts from the northwest and southeast Dellwood Knolls appear to be related by crystal fractionation, based on major element analysis. However, the very different REE patterns and Sr⁸⁷/Sr⁸⁶ ratios exhibited by the two knolls suggest that they have different mantle sources, one typically depleted (northwest knoll) and one chemically and radiogenically enriched (southeast knoll). In terms of their major and trace element chemistry, the J. Tuzo Wilson Knolls basalts are typical of late-stage volcanism on ocean islands associated with mantle plumes. The hawaiites strongly resemble alkali basalts dredged from several seamounts in the Pratt-Welker Chain, which are co-latitudinal with the J. Tuzo Wilson Knolls on a small circle about the Pacific-Hotspot pole of rotation. Geochronological evidence questions the hypothesis that the mantle plume responsible for Pratt-Welker volcanism is also the source for the J. Tuzo Wilson basalts. The existence of a second mantle plume, 300 km southeast of the first, would explain minor chemical and physiographical differences between the Knolls and the other Pratt-Welker seamounts, as well as the evidence for two phases of volcanism on the southeastern seamounts of the chain. A second plume also explains the coeval volcanism of Bowie Seamount and the J. Tuzo Wilson Knolls. Recent geophysical evidence suggests that the J. Tuzo Wilson Knolls are also part of the Explorer-Dellwood spreading system. Although the JTW basalts are plume-type basalts chemically, the situation appears to be somewhat analagous to other ridge segments where plumes are coincident with the ridge itself. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
546

Tracing change in Northwest Coast exhibit and collection catalogues, 1949-1998

Goudie, Tanya 11 1900 (has links)
This thesis explores changing perceptions, theory, structure and policy within art exhibit and collection catalogues of First Peoples' objects from the Pacific Northwest Coast. This work looks at emerging viewpoints on material culture and its display over forty years as they present themselves in catalogue entries, textual content and labeling of Native groups and individuals. Early concepts based on salvage anthropology such as Native cultural demise and the degeneration of remaining people weakened as scholarship changed from a predominantly anthropological understanding of the objects to an aesthetic understanding based in art history. Political actions by Native groups have demanded policy changes within Canadian museum structure that includes the Native voice in curatorial decisions and textual discussions on both old and new objects. These very policy changes bring with them increased responsibility for the museum as well as new challenges of representation of the objects and their makers. The theme explored in this thesis is the changing role and responsibility of academia in the representation of the Other. / Arts, Faculty of / Anthropology, Department of / Graduate
547

Contesting modernism : communities and the pacific salmon revitalization plan

Robertson, Stephen 05 1900 (has links)
This thesis explores the role for social work in addressing government policies that threaten the sustainability of small coastal communities. The response of government and industry to the globalization of trade and resource degradation is at odds with the needs of people. Utilizing a case study methodology the development and implementation of the Pacific Salmon Revitalization Plan is explored. This department of fisheries plan to rationalize the fishery was highly contested on the grounds that it took jobs out of small coastal communities. It was accused of benefiting the large fishing corporations and the urban based fishing fleet, which had the capital to profit from the plan. Concentrated opposition from coastal communities, fishers, advocacy groups and academics was unsuccessful in changing the plan. The assumptions of modernism - expert knowledge, scientific rationality and orthodox economics - as well as distorted communications, were postulated to be behind this lack of success. A post modern analysis suggests that a successful challenge to the plan would have incorporated the local knowledge of fishers and coastal communities within a process of fair and equitable public discourse aimed at reaching intersubjectively mediated understanding. For social work this demonstrates the need to work conjointly with communities and affected groups to identify the modernist assumptions on which policy decisions are based and develop locally derived alternatives to these assumptions. And most importantly, that the focus of social change efforts be on demanding a process for discussion and decision-making that ensures that the concerns of effected individuals will be fairly addressed. / Arts, Faculty of / Social Work, School of / Graduate
548

Spatial Segregation of the Sexes in a Salt Marsh Grass Distichlis spicata (Poaceae)

Mercer, Charlene Ashley 01 January 2010 (has links)
Understanding the maintenance of sexual systems is of great interest to evolutionary and ecological biologists because plant systems are extremely varied. Plant sexual systems have evolved to include not only complete plants with both male and female reproduction occurring on one plant (i.e., monoecious and hermaphroditic) but also plants with male and female function on separate plants (dioecious). The dioecious reproductive system can be used to test theories on niche differentiation given that having separate plants potentially allows for the exploitation of a broader niche. This increase in the realized niche is due to the ability for separate sexes to occupy different niches, which may occur in different physical habitats. Some dioecious plants have been shown to occur in areas biased to nearly 100% male or nearly 100% female, called spatial segregation of the sexes (SSS). Occupying a broader niche could increase fitness in some species when the separation is used for one sex to gain access to resources that increase reproductive success and/or if the separation inhibits deleterious competition. These two mechanisms have been previously proposed for the evolution of SSS in dioecious plants. The first mechanism suggests that males and females have evolved to occupy different niches due to differences in reproduction (sexual specialization). The hypothesis for the sexual specialization mechanism is that females should have higher fitness in female-majority sites and males should have higher fitness in male-majority sites. The second mechanism states that males and females occupy different niches due to competition between the sexes (niche partitioning). The hypothesis for niche partitioning states that inter-sexual competition should decrease fitness more than intra-sexual competition. These mechanisms are not mutually exclusive. In our research we use the salt-marsh grass Distichlis spicata as our study species because this plant is dioecious and because molecular markers have been developed to determine the sex of juvenile plants. These molecular markers are important for testing the niche partitioning hypothesis for SSS in juveniles. Furthermore, previous work in California has shown that plants occur in areas nearly 100% female and nearly 100% male called spatial segregation of the sexes (SSS). The previous research also showed that female-majority sites were higher in soil phosphorus than male-majority sites. We conduct all research, presented in the proceeding chapters, on Distichlis spicata in the Sand Lake estuary near Pacific City, Oregon and in the laboratory at Portland State University. In Chapter 1 we used field data to answer two questions: (1) Does Distichlis spicata exhibit SSS in Oregon, and (2) If SSS is occurring, do differences occur in plant form and function (sexual specialization) in reproductive female and male plants in female-majority and male-majority sites? We used a sex ratio survey and collected field data on reproductive males and females. Our results show that there are female-majority and male-majority areas and SSS is occurring in the Sand Lake Estuary. Results from our native plant data suggest that reproductive females perform better in female-majority sites compared to male-majority sites which could suggest that sexual specialization is occurring in females. We currently have a long term field reciprocal transplant experiment in place to further address this hypothesis. In Chapter 2 we use field dada to address the following questions: (1) Does site-specific soil nutrient content occur in August, when females have set seed? (2) Does sex-specific mycorrhizal colonization occur in reproductively mature plants? (3) Does sex-specific mycorrhizal colonization vary seasonally in natural populations? Inside the roots of D. spicata a symbiotic relationship is formed between plant and arbuscular mycorrhizal fungus (AM). The AM- plant relationship has been shown to thrive in phosphorus limited areas because the mycorrhizal fungus increases nutrient access to the plant. We analyzed the results of the field soil nutrient content and mycorrhizal colonization in roots of native Distichlis spicata from male-majority and female-majority sites. The root colonization included staining roots with trypan blue and viewing sections of the roots under the microscope. Our results show that female- majority sites are higher in phosphorus and are found to have higher AM colonization than male- majority sites in the field. In Chapter 3 we then reciprocally transplanted D. spicata plants in the field to address the following questions: (1) Does niche partitioning occur in D. spicata, and (2) If niche partitioning is occurring, which plants are competing more? Our reciprocal transplant experiment included seeds grown in intra-sexual, inter-sexual and no competition in cones, planted directly into the field, and allowed to grow for 15 months. After the 15 months was over we measured survival, dry weight and root/shoot ratio. The design of the experiment was to determine the effects of competition (intra-sexual and inter-sexual) and no competition on (single male and female) on survival, biomass and root/shoot ratios. Our results show that niche partitioning is occurring and plants in inter-sexual competition have significantly less biomass then intra-sexual competitors. In, Chapter 4, we conduct a laboratory experiment to address the following questions: (1) Do plants show plasticity in their response to root exudates of the competing plant in regards to the sexual phenotype of the competitor? (2) Do plants show plasticity in their response to root exudates of the competing plant with respect to the relatedness of the competitor? We use sterile seeds grown in 24-well plates containing liquid media. For each competing plant, we picked plants up out of the wells and into the competing plants wells so that plants only experienced media that the competing plant had grown. At no time do roots ever come into contact with one another. We measured primary root length, number of lateral roots, the number of root hairs, root/shoot ratio and total dry weight. We analyzed the study two different ways, one for sexual type competition (inter-sexual, intra-sexual, none) and for plant relationship (KIN, STRANGER and OWN). The results for the sexual type competition found that inter-sexual competition was greater for root/shoot ratio and dry weight. The results for plant relationship competition found that kin plants had a significantly greater number of lateral roots and a significantly longer primary root. The last chapter, Chapter 5, includes a summary of our conclusions. Our study found SSS occurring in the Sand Lake Estuary in Oregon with female-majority sites higher in phosphorus and root colonization higher in percent colonization of arbuscular mycorrhizal fungi compared to male-majority sites. Based on the sexual specialization hypothesis as a mechanism for SSS, we found that females had greater fitness in female-majority sites compared to male-majority sites, suggesting that sexual specialization is occurring in reproductive females. We then tested the niche partitioning hypothesis for SSS, and we found consistent lab and field results suggesting that niche partitioning due to inter-sexual competition is an explanation for why females and males D. spicata plants spatially segregate themselves at the juvenile life history stage. Furthermore, we found that plants that have the same mother had a significantly greater number of lateral roots and a significantly longer primary root. These results suggest that KIN plants respond differently to one another compared to plants paired with a plant not from the same mother (STRANGER) or when the plant is alone (OWN).
549

Age Determination of Modern and Archaeological Chinook Salmon (Oncorhynchus tshawytcha) Using Vertebrae

Hofkamp, Anthony Raymond 30 March 2015 (has links)
Incremental growth rings in X-rays of salmon vertebrae have been used since the 1980s to age Pacific salmon (Oncorhynchus spp.) remains from archaeological sites in the Pacific Northwest. These age estimates, paired with generalized life history patterns, have been used to determine salmon species, season of capture and in turn season of site occupation. This approach relies on a variety of assumptions, the most fundamental of which is that rings represent true years. Archaeologists using vertebral age determination techniques have failed to adequately test this assumption and present their methodologies. This thesis assesses the validity of using incremental growth structures in Chinook salmon (Oncorhynchus tshawytscha) vertebrae to determine the age at death of fish represented in archaeological sites. This project develops criteria and a protocol for the identification of true annuli and tests these identifications on a collection of modern Chinook salmon of known age. Finally, this protocol is applied to archaeological remains of Chinook from Cathlapotle (45CL1). Three collections of modern known age fish (N=121) were used to evaluate and test approaches to aging Chinook salmon with vertebrae. These collections contained juvenile and adult Chinook from throughout Washington and Oregon. I evaluated a variety of methods for viewing rings including magnified surface images, X-ray images and thin sections to determine which is the most accurate, reliable and efficient, also considering the extent of specimen destruction. Rings visible in X-rays were found to reflect the internal structure of vertebrae rather than annular growth. The number of these internal walls did not correspond to the known ages of fish and are therefore not true annuli. Criteria previously described by salmon fisheries biologist were used to isolate annuli (on the centrum surface) on the Hanford reach collection (N=46). In a test for accuracy 39 (85%) were aged correctly. In a test of reliability utilizing five additional readers all but 14 cases showed discrepancies among readers. Results of the test of reliability were not as successful as other researchers in fisheries biology but given the high accuracy rate the method remains valid. The final goal of this project was to determine the feasibility of applying the surface ring method of age determination to archaeological collections. Archaeological salmon vertebrae from Cathlapotle (45CL1) on the lower Columbia River, Washington state were utilized. One hundred salmon vertebrae were selected and classified to species according to Huber et al. (2011); 89 were identified as Chinook. Of these, 39 had sufficient preservation of the surface to view and interpret incremental rings. Three ages were identified 3, 4 and 5 year olds. This ageing protocol can be applied to archaeological Chinook salmon vertebrae to estimate age of ancient Chinook salmon. Additional work is needed on other salmon species to demonstrate the methods validity across all salmonid species. This analysis has great potential for modeling salmon paleo-life history by contributing data from salmon populations prior to the major impacts of the 19th and 20th century. This is particularly valuable for salmon conservation because information on size, the timing and duration of freshwater emigration as well as the age of spawning and death is critical to the management of hatchery and wild salmon populations.
550

Event Ecology: An Analysis of Discourses Surrounding the Disappearance of the Kah Shakes Cove Herring (Clupea pallasi)

Hebert, Jamie Sue 01 January 2011 (has links)
The conflict over the herring run at Kah Shakes is complicated. In 1991, the Alaska Department of Fish and Game (ADFG) expanded the commercial herring sac roe fishing boundary in the Revillagigedo Channel to include Cat and Dog Islands. Native and non-Native local residents of Ketchikan protested the boundary expansion, as did managers of the neighboring Annette Island Fishery managed by the local reservation. Using cultural anthropological research methods that include ethnographic data, semi-structured, qualitative interviews gathered in southeast Alaska in 2008, and a comprehensive literature review of historic data culled from newspapers and other texts, I examine the many political factors that contribute to this conflict, including the contest between anecdotal and scientific data, the construction of fisheries management boundaries, and issues of collective memory. Using Vayda and Walters' event ecology methodology, bolstered by discourse analysis, I identify three discourses (local ecological knowledge, management and environmental). I use these discourses as comparative units to show that little coincident data can be identified between these discourses. I examine two areas of dissident data, stock definition and measures of abundance, and recommend that local ecological knowledge (LEK) be used to expand the scientific database on which current management techniques depend, to question the accuracy of current ADFG management boundaries and stock identification, and to recalibrate guideline harvest levels by exposing the effects of shifting baselines. I then outline how Geographic Information Systems (GIS) may assist in the validation and integration of LEK into the current fisheries management paradigm to create a more holistic narrative of ecological change.

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