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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.
61

The Effects of Past Climate Change and Recent Agricultural Irrigation Recharge on the Sources, Ages, and Quality of Groundwater in the Columbia River Basalt Aquifers, Columbia Basin, Central Washington

Brown, Kyle January 2009 (has links)
This study uses multiple isotopic (2H, 18O, 13C, 15NNO3, 18ONO3, 87Sr/86Sr) and age tracers (3H, 14C, CFCs), in conjunction with elemental chemistry, to address the following research question: How have present day anthropogenic activities (i.e. surface water irrigation and fertilizer application) and past climatic events (i.e. cataclysmic flooding from glacial Lake Missoula and other modes of discharge from Cordilleran Ice Sheet) impacted the hydrology and geochemistry of the Columbia River Basalt Aquifers (CRBAs) in central Washington? Large-scale irrigated agriculture over the past ~60 years has resulted in the transport of high NO3- irrigation waters moving downward in the oxic CRBAs at rates of several meters per decade with a lack of denitrification. Deeper pristine regional groundwater in the CRBAs is Late Pleistocene in age and likely remnant Cordilleran Ice Sheet-related recharge waters (i.e. glacial Lake Missoula floodwaters).
62

Primary biomass and production processes in the Columbia River estuary

Lara-Lara, Ruben 09 August 1982 (has links)
Graduation date: 1983
63

Three-dimensional circulation dynamics of along-channel flow in stratified estuaries /

Musiak, Jeffery Daniel. January 1998 (has links)
Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [111]-116).
64

Seasonal and tidal influence of the estuarine turbidity maximum on primary biomass and production in the Columbia River estuary /

Morgan, Stacey Rose. January 1992 (has links)
Thesis (M.S.)--Oregon State University, 1993. / Typescript (photocopy). Includes bibliographical references (leaves 85-87). Also available on the World Wide Web.
65

Wave propagation processes at the mouth of the Columbia River /

Andes, Lisa January 1900 (has links)
Thesis (M.Oc.E.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 51-54). Also available on the World Wide Web.
66

Resolving Upper Mantle Seismic Structure Beneath the Pacific Northwest and Inferred Plume-Lithosphere Interactions During the Steens-Columbia River Flood Basalt Eruptions

Darold, Amberlee, Darold, Amberlee January 2012 (has links)
Cenozoic tectonics of the Pacific Northwest (PNW) and the associated mantle structures are remarkable, the latter revealed by EarthScope seismic data. In this thesis we model teleseismic body waves constrained by ambient-noise surface waves and teleseismic receiver function analysis in order to recover better-controlled higher resolution images of the PNW continuously from the surface of the crust to the base of the upper mantle. We focus on and have clearly imaged two major upper mantle structures: (1) the high-velocity Farallon slab (the "Siletzia curtain") extending vertically beneath the Challis-Kamloops-Absaroka volcanic flareup (~53-47 Ma) of western Idaho and central Washington; and (2) a high-velocity anomaly beneath the Wallowa Mountains of northeast Oregon associated with the main Columbia River flood basalts source region. The proximity of these two structures along with the tectono-magmatic history of the PNW leads us to reexamine the origin of the Columbia River Basalts ~ 16 Ma. This thesis includes co-authored material submitted for publication.
67

Planning for climatic variability

Rutgers, P. U. January 1977 (has links)
According to most climatologists the recent weather extremes are symptomatic of the return to a more variable climate after an unusually warm and stable thirty to forty years that came to an end in the early 1970s. This prolonged climatic stability has institutionalised the concept of a stable climate among most policy and decision makers and consequently, most life support systems, food, energy and water have been planned for too narrow a range of climatic variability. Recent events begin to illustrate the serious impacts that a more variable, but more normal, climate has on these systems. This thesis has attempted to: 1. Assess the impact of increased climatic variability on the generating capacity of the Mica and Revelstoke Dams projects and other components of B.C. Hydro's integrated power generation system. 2. Develop a planning response to climatic variability in the context of electricity generation planning in British Columbia. The study included a review of literature on climatic change, a review of literature on planning under uncertainty, the development of a planning model and the application of this model to the hydroelectric developments in the Upper Columbia River Basin. The planning model is iterative and recognises seven phases: problem recognition, system identification, identification of uncertainty, exploration of uncertainty, formulation of alternatives, evaluation, and development of a commitment package. The case study provides an application of this model to the management of the Mica and Revelstoke Dams, and the construction and management of other components of the integrated generation system. The forty year streamflow record (1928-1968), the basis of generation planning, appears to be unusually stable when compared to historic variability as indicated by relevant tree-ring data. The "critical" period on which the system's firm energy capability is based is exceeded in the Lake Athabasca chronology. This tree-ring chronology, which correlates well with the Columbia River streamflow, contains evidence of a drought, twice the magnitude and three times the duration of the critical period, which might have struck the Rocky Mountains between 1864 and 1880. Under these conditions the Mica and Revelstoke Dams would generate respectively 19$ and 17-8$ below design production. These losses could be absorbed by the,integrated system, but further reductions in output, possibly arising in the post draw-down period might, beyond 1980, lead to overall supply shortfalls. If this drought were to simultaneously affect all hydroelectric generation plants, power shortages of between 2$ and 6$ of annual demand loads could be expected. To improve the electricity generating system's resilience to climatic variability, it is recommended that initially B.C. Hydro develop and implement an energy conservation program, which would reduce forecasted demands by 6% by 1980, contract power to new industrial customers on an interruptible basis, extend the streamflow records of the Peace and Columbia Rivers by means of tree-rings and monitor climatic research. The extended record should form the basis of a new energy capability balance and some of the options the authority could then consider are the creation of a thermal power reserve, the increase of live storage in existing and future reservoirs, the installation of additional generating equipment and the development of contingency plans to further curtail demand and utilise the thermal reserve. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate
68

The Emergence of Longview, Washington: Indians, Farmers, and Industrialists on the Cowlitz-Columbia Flood Plain

Rushforth, Brett H. 01 May 1998 (has links)
This thesis examined the relationships among ecology, economy, and society in the history of Longview, Washington, a planned timber settlement on the Columbia and Cowlitz Rivers. It compared the environmental, economic, and social histories of the Cowlitz Indians, American farmers, and urban industrialists that lived there over the past four hundred years. The central argument of the thesis is that human society cannot separate its economic and social organization from its ecology, nor can it reorder the environment without restructuring its economic and social institutions. Three different groups lived in the same physical space, but since they conceived and used the land differently, their societies developed distinct social and economic frameworks. The narrative of the thesis is chronological, tracing environmental, economic, and social change from about 1790 to 1934. During that time, humans gradually transformed a flood plain once dominated by vegetation and wildlife into a paved, sculpted, and densely populated industrial city. This study outlines the major causes and consequences of that transformation for both the land and its inhabitants. A wide range of source material provided the evidence upon which my conclusions were based. In addition to the more conventional historical sources such as diaries, letters, newspapers, memoirs, maps, and census data, I consulted anthropological studies, geological and geographical surveys, ecological reports, agricultural bulletins, and sociological analyses. My findings are presented in Chapters 2 through 5, with chapter 6 summarizing and drawing final conclusions.
69

The fisheries of the Lower Columbia River, 1792 to 1850, based on EuroAmerican explorer and fur company accounts

Martin, Michael A. 10 August 2006 (has links)
The role of fish in the Native American economy of the lower Columbia River has never been considered in detail. My study focused on the Columbia River from its mouth to the Cascades and the Willamette River from its confluence with the Columbia to Willamette Falls. For this study I asked: How was salmon used? What other fish were important? Where and how were these fish taken and used? To address these questions, I evaluated historical documents, including explorer's accounts and the administrative records of fur companies dating from the late 1700's through the 1850's. I used fishery data, physical descriptions, migratory and spawning habits, and foraging patterns to identify fish in historic accounts. I annotated historic information and provided a synthesis of the historic fisheries. White sturgeon (Acipenser transmontanus), eulachon (Thaleichthys pacificus) and chinook salmon (Oncorhynchus tshawytscha) dominated the trade. Chum (O.keta) and lamprey (Lampetra sp.) were available, although not traded in large numbers. White sturgeon, eulachon, fall chinook, chum and lamprey were smoke cured. Steel head (0. mykiss) , coho (O.kisutch), perch (Embiotocidae), and resident trout were traded in small numbers indicating that other fish were part of the economy. Sockeye. salmon (O.nerka) was not traded. f "~{.' Indians captured white sturgeon with: multiple hooks on set-lines and funnel nets to take white sturgeon during the winter; scoop nets and the eulachon rake took eulachon; spring and summer chinook were taken with hoop nets and platforms in the Cascades rapids and at Willamette Falls; gaffs were used to take chinook and sturgeon during the summer in Baker Bay; and hoop nets took fall chinook in streams. Seine nets were noted but not were not discussed except for the chinook fishery of Baker Bay. Historic information on fishes used and methods of capture contrasts with the archaeological record of the Portland Basin. Resident freshwater fish, minnows (Cyprinidae) and suckers (Catostomus sp.), are abundant in the archaeological faunal record, but are rarely mentioned in historic accounts. Artifacts such as net weights are common in archaeological contexts in contrast with the limited discussions in the historic record. Possible explanations for these discrepancies are reviewed.
70

Economic significance of the preference clause in public water policy on the development of the Pacific Northwest /

Farris, Martin T. January 1957 (has links)
No description available.

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