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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.
191

Late quaternary sea-level lowstand environments and chronology of outer Saco Bay, Maine /

Lee, Kristen M. January 2006 (has links) (PDF)
Thesis (M.S.) in Earth Sciences--University of Maine, 2006. / Includes vita. Includes bibliographical references (leaves 109-119).
192

Some effects of growing season soil moisture and microclimate on redwood seedlings in a forest edge and gap environment /

Mercer, Justin A. January 1900 (has links)
Thesis (M.S.)--Humboldt State University, 2006. / Includes bibliographical references (leaves 39-42). Also available via Humboldt Digital Scholar.
193

Measuring and Modeling Exposure from Environmental Radiation on Tidal Flats

Gould, Travis J. January 2004 (has links) (PDF)
No description available.
194

Analysis of coastal erosion on Martha's Vineyard, Massachusetts a paraglacial island /

Brouillette-Jacobson, Denise, January 2008 (has links)
Thesis (M.S.)--University of Massachusetts Amherst, 2008. / Includes bibliographical references (p. 392-481).
195

An evaluation of North Carolina's mandatory oceanfront setback policy : a case study of Nags Head /

Thomas, Claire H., January 1994 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 141-143). Also available via the Internet.
196

Field observations of infragravity wave response to variable sea-swell wave forcing

Inch, Kris William January 2017 (has links)
Infragravity waves are low frequency (0.005-0.04 Hz) waves that can dominate the spectrum of water motions and sediment transport processes within the inner surf zone. Despite the established importance of infragravity waves in shaping our coasts and numerous studies dating back to the 1950s, several aspects of infragravity wave analysis, generation and dissipation remain poorly understood. As much of the recent infragravity research has focussed on fetch-limited coasts, less is known about the climatology of these waves on energetic coastlines subject to both swell and fetch-limited waves. It has been postulated that bed friction only plays a significant role in the dissipation of infragravity waves where the bed is exceptionally rough, but the precise impact of bed roughness is not fully understood, particularly on extremely rough rock platforms. Finally, although there have been many methodologies proposed for the decomposition of reflective wave fields (an essential tool for studying infragravity wave dynamics), very little attention has been given to evaluating their accuracy, particularly the impact of uncorrelated noise. This study aims, primarily through the collection of an extensive field dataset and the establishment of accurate analysis tools, to provide new insight into the propagation, dissipation and reflection of infragravity waves on energetic coastlines of varied roughness, subject to both swell and fetch-limited waves. To ensure the accurate decomposition of infragravity wave signals into their incident and reflected components, a sensitivity analysis into the effect of uncorrelated noise on an array separation method is performed. Results show that signal noise, often prevalent in field data, introduces a significant bias to estimates of incident and reflected wave spectra, and corresponding reflection coefficients. This bias can exceed 100% for signal-to-noise ratios of < 1. Utilising the systematic change in coherence with noise, a correction function is developed which is effective at reducing bias by up to 90%. When applied to field data, results imply that infragravity reflection coefficients can be overestimated by > 50% if signal noise is unaccounted for. Consequently, noise reduction should form an integral part of future infragravity wave studies. New research from a dissipative, fetch-unlimited sandy beach (Perranporth, Cornwall, UK) and a macrotidal, rocky shore platform (Freshwater West, Pembrokeshire, UK) uniquely demonstrates that the level of infragravity wave energy close to shore is linearly dependent on the offshore short wave energy flux H_o^2 T_p (r^2 = 0.93and 0.79, respectively). Infragravity waves approach the coast as bound waves lagging slightly (~4 s) behind the wave group envelope and are released in the surf zone where their heights can exceed 1 m. Considerable infragravity dissipation is observed in the surf zone and is a function of both frequency and H_o^2 T_p. Complex Empirical Orthogonal Function (EOF) analysis reveals (quasi-)standing waves at low infragravity frequencies < 0.017 Hz. Conversely, at higher frequencies (>0.017 Hz), infragravity waves demonstrated progressively more dissipation (up to 90%) and progressive wave characteristics, with increasing frequency. Much of the observed dissipation occurs very close to shore (h < 0.8 m) and the dependence of the reflection coefficient on a normalised bed slope parameter implies a mild sloping bed regime at these high infragravity frequencies, suggesting that the observed dissipation is dominated by wave breaking processes. This is supported by the results of bispectral analysis which show predominantly infragravity-infragravity interactions in shallow water and the development of infragravity harmonics indicative of steepening and eventual breaking of the infragravity waves. This study presents the first simultaneous field observations of infragravity waves on a macrotidal, rocky shore platform and adjacent sandy beach. Infragravity wave dissipation is observed on both the platform and beach and occurs at statistically similar rates, demonstrating that frictional dissipation due to bed roughness is not the dominant dissipation mechanism, even in this extreme case. Sea-swell waves are also unaffected by the extreme roughness of the platform, with relative wave heights on the beach and platform (γ = 0.38 and 0.43, respectively) scaling well with their respective gradients and are in very close agreement with formulations derived from sandy beaches. Overall, bed roughness is shown to have no significant impact on infragravity or sea-swell wave transformation, with offshore forcing and bed slope being the main controlling factors, particularly under moderate to high energy offshore forcing.
197

Ecological interactions of three Littorina (Gastropoda, prosobranchia) along the West coast of North America

Behrens, Sylvia, 1946- 09 1900 (has links)
Thesis, Ph.D., Oregon, Dept. of Biology Vita Bibliography: l. 109-111
198

The Influence of Deep-Seated Landslides on Topographic Variability and Salmon Habitat in the Oregon Coast Range, USA

Beeson, Helen 29 September 2014 (has links)
A well-accepted idea in geomorphology is that landforms control the type and distribution of biological habitat. However, the linkages between geomorphology and ecology remain poorly understood. In rivers, the geomorphic template controls the hydraulic environment, partly shaping the river ecosystem. But what processes shape the geomorphic template? Here, I examine how two hillslope processes dominant in the Oregon Coast Range, debris flows and deep-seated landslides, affect valley floor width and channel slope, key components of the geomorphic template in riverine ecosystems. I then investigate how patterns in potential salmon habitat differ between streams dominated by deep-seated landslides and streams dominated by debris flows. I show that terrain influenced by deep-seated landslides exhibits (1) valley widths that are more variable throughout the network but less locally variable, (2) more variable channel slopes, and (3) more potential salmon habitat as well as significantly more connectivity between habitat types.
199

Coast Salish artist Douglas LaFortune: deconstructing Euro-settler narratives of Indigenous artistic practice and investigating active cultural practice through collaborative witnessing

Drummond, Justine Auben 02 January 2019 (has links)
Douglas (Doug) LaFortune is a Coast Salish Master Carver and Graphic Artist of both Quw’utsun’ (Cowichan) and Tsawout, WSÁNEĆ (Saanich) heritage, with an artistic career spanning over four decades (City of Duncan 2013:2,6,21,28; Coastal Peoples n.d.). By examining how Douglas’ life and work are intertwined in the active practice of his culture, this thesis challenges harmful Euro-settler institutional narratives of Indigenous art that privilege authenticity-as-tradition and place Indigenous cultures in a mythical pre-contact past, thus dismissing references to their lived experiences as inauthentic (Phillips 2012:113; Tupper et al. 2013:42). This project is rooted in community. Douglas and his wife Kathleen told my supervisor, Dr. Andrea Walsh, that they wished to organize their collection of Douglas’ drawings and prints (dating from the 70s until the present). Dr. Walsh recommended me (Justine Drummond) for this work, and I agreed to catalogue, photograph, and organize the collection. Through examining Douglas’ collection and work as a whole, I witnessed the relationality of his artistic practice, as it is inextricable from family, place, and culture (Wilson 2008:80, 87). This was further illuminated in interviews with Douglas, Kathleen, and their granddaughter, Seneca, which I conducted through collaborative witnessing, wherein I acted as a co-storyteller with the participants (Adams et al. 2015:4,54-56). The thesis structure is as follows: the introduction outlines my research objectives and a brief biography of Douglas; chapter 2 reviews the literature on decolonizing approaches towards Coast Salish art; chapter 3 details my methodology and data collection process; chapter 4 presents Douglas, Kathleen, and Seneca discussing their lives as lived through art; chapter 5 explores Douglas’ collection, and his entire body of artistic work; and chapter 6 is the conclusion. / Graduate
200

Long-term use of fish and shellfish resources revealed through vibracore sampling at EjTa-13, Hecate Island, Central Coast, BC

Duffield, Seonaid Eileen Shute 03 January 2018 (has links)
This Master’s research program was undertaken as part of the Hakai Ancient Landscapes Archaeology Project in Heiltsuk and Wuikinuxv Territories on the Central Pacific Coast of British Columbia (BC), Canada. The project tested the utility of applying vibracore technology to sample a shell midden site on Hecate Island on the BC Central Coast. This revealed that the earliest archaeological occupation began approximately 6,000 years ago, continuing into the 16th Century AD. Analysis using 21 radiocarbon dates from six core samples shows the site was repeatedly occupied and accumulated consistently throughout the tested area and extended to a depth of 544 cm depth below surface. Sampled sediments were utilized to evaluate evidence of fisheries resource management through time with reference to the nearby, intensively-studied archaeological site Namu (ElSx-1). Zooarchaeological results show the herring (Clupea pallasii), salmon (Oncorhynchus spp.), rockfish (Sebastes spp.) and greenling (Hexagrammos spp.) were fished persistently and in similar abundances through the occupation of the site. Overall results for vertebrate fauna reveal the total number of specimens is 19,173 and the total number of identified specimens is 6,566. Results also show a consistent harvest of certain shellfish taxa (e.g., mussel and barnacle), however shellfish weight per litre increases through time. When comparing the relative abundance of herring and salmon through time at Namu and EjTa-13, results show that salmon at Namu was more abundant than at EjTa-13. This is likely due to the productivity of salmon in the Namu River adjacent to the site. Alternatively, herring remains were represented similarly between sites indicating the resource was equally desirable at EjTa-13 and Namu. Surprisingly, a large number of very small artifacts of various materials were also recovered (an estimated 550 artifacts per cubic metre of cultural sediments), which indicates that the field and laboratory methods used are especially conducive to the recovery of small items. These results show a persistent and sustainable local fishery through six millennia until the contact period. / Graduate / 2018-12-15

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