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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

Inventing the Salish Sea: Exploring the Performative Act of Place Naming off the Pacific Coast of North America

Tucker, Brian Justin 01 May 2013 (has links)
Over the past two decades, a growing number of scholars have begun to explore the cultural politics of toponymic inscription. The current study contributes to the emerging literature on critical place-name studies by examining the cultural and political implications of the recent designation of the “Salish Sea,” a new name given to the water body adjacent to the shared Pacific coastline of Washington State and the Province of British Columbia. Through a critical analysis of archival materials and semi-structured interviews with participants from a variety of different groups, this case study adopts a performative approach to consider the ways in which the naming of places is implicated in the rescaling of public conceptions of “place” through the performative enactment of spatial identities. In doing so, it illustrates the importance of narrative as an integral part of the cultural production of place. Although this new toponym was initially promoted to raise ecological awareness, it also has considerable implications for reshaping the political, economic, and cultural geographies of the region. Furthermore, the findings conclude that when assessing the designation’s impact on the relations between the Indigenous and Settler populations of the area, evidence points to the official naming being representative of an act of “anti-conquest”: an act that glorifies the Indigenous culture while providing no actual exchange of power or opportunity for increased levels of self-determination. / Graduate / 0366 / 0740 / btucker@uvic.ca
2

The 'How' of Transformative Change: Stories from the Salish Sea Islands

Weller, Fay Elizabeth 20 September 2013 (has links)
This dissertation explores how transformative spaces and agency provide opportunities in everyday lives for transformative shifts from the dominant culture towards a culture of ecological decision-making. Stories about transformative change and system shifts, told by forty people involved in Canada’s Gulf Islands, form the basis for the findings. Their stories demonstrate how personal transformation leads to changed lifestyles and system shifts that reflect the interconnectedness between all living organisms. Two elements of the shift to ecological thinking are increased understanding of the natural world, and willingness to hear and empathise with other people’s realities. Change in communities is cumulative and unpredictable, mirroring personal transformation. Community self-governance is at the core of cultural shifts – the extent to which community members, with various purposes and realities, engage in empathetic dialogue. When interacting with governments and corporations, those who have shifted to ecological-thinking mode exercise their agency and respond according to their inner values. Factors that increase the likelihood of cultural shifts include: a) a multiplicity of different realities in the same space that create the opportunity for people to rethink their cultural box and see the arbitrariness of dominant norms, b) people exercising their agency rather than looking to government as authority, c) collective, non-hierarchical processes, and d) support and links to others in a network of symbiotic ecological-thinking nodes. The power in d) is the power of an accumulation of localisms that creates cultural shifts, arising from communities, which shifts society’s norms and behaviours. / Graduate / 0329 / 0615 / fayweller@shaw.ca
3

Long-term spatial-temporal eelgrass (Zostera marina) habitat change (1932-2016) in the Salish Sea using historic aerial photography and unmanned aerial vehicle

Nahirnick, Natasha K. 18 May 2018 (has links)
Eelgrass (Zostera marina) is a critical nearshore marine habitat for juvenile Pacific salmon (Oncorhynchus spp.) as they depart from their natal streams. Given the poor marine survival of Coho (O. kisutch) and Chinook (O. tshawytscha) salmon juveniles in recent decades, it is hypothesized that deteriorating eelgrass habitats could contribute to their low survival. The primary goal of this research was to investigate the possible long-term spatial-temporal trends in eelgrass habitat in the Salish Sea and was addressed by two main objectives: (1) Define a methodology for mapping eelgrass habitats using UAV imagery to create a baseline for long-term mapping; and (2) Assess changes in eelgrass area coverage and fragmentation over the period of 1932-2016 using historic aerial photographs and Unmanned Aerial Vehicle (UAV) imagery, and assess the relationship between eelgrass and residential housing density and shoreline activities. Three study sites in the Southern Gulf Islands of the Salish Sea were chosen for analysis. The overall accuracies of eelgrass delineation from UAV imagery were 95.3%, 88.9%, and 90.1% for Village Bay, Horton Bay, and Lyall Harbour, respectively. The UAV method was found to be highly effective for this size of study site, however results were impacted by the environmental conditions at the time of acquisition, namely: sun angle, tidal height, cloud cover, water clarity, and wind speed. The results from the first objective were incorporated into a long-term dataset of historic aerial photography and used to evaluate changes in eelgrass area and fragmentation. All three eelgrass meadows showed a deteriorating trend in eelgrass condition. On average, eelgrass area coverage decreases by 41% while meadow complexity as indicated by the shape index increases by 76%. Shoreline activities (boats, docks, log booms, and shoreline armouring) and residential housing density increased markedly at all sites over the study period. By using a linear correlation model, it was revealed that eelgrass areal coverage and fragmentation (Shape Index) were, in general, very strongly correlated to these landscape-level coastal environmental indicators. While this correlation model is not meant to show a direct causative impact on eelgrass at these sites, these results suggest an overall deterioration of coastal environmental health in the Salish Sea due to a dramatic increase in the use of the coastal zone, as well as likely declines in water quality due to urbanization. / Graduate
4

Satellite remote sensing of Nereocystis luetkeana (bull kelp) and the use of kelp by juvenile salmon in the Salish Sea

Schroeder, Sarah 19 December 2019 (has links)
The macro-algae Nereocystis luetkeana or bull kelp is an important canopy-forming species in the rocky nearshore ecosystems of the Salish Sea. It provides structural habitat for many fish and invertebrates including juvenile salmon. In the Pacific Northwest, major declines in Chinook and Coho salmon populations have led to increased scientific efforts to determine the causes behind these losses. High mortality of juvenile salmon during their first months in the marine environment may be linked to loss of habitat such as kelp beds, which can provide shelter, concentration of prey and energetically favorable conditions. This work seeks to understand the role of kelp habitat in the early marine growth period of juvenile salmon. Initially, methods using satellite imagery were developed for mapping the location of kelp beds adjacent to a salmon bearing river in Cowichan Bay, on the West Coast of British Columbia. These methods were then applied to a time series of imagery from 2004 to 2017, to determine how kelp beds are changing over time and the possible drivers of those changes. The results found spatial and temporal variability in kelp beds with a decline from a high in 2015 to the lowest levels in 2017. The observed changes were over a short period considering the natural variability of Nereocystis and continued long term monitoring will help to determine if the declines are permanent. Spatial and temporal variability were found to relate to substrate type, current strengths and potential lag effects of declines due to warmer than average sea surface temperatures. Lastly, the maps created through satellite-based methods served to inform surveys investigating the importance of kelp habitat to the declining populations of Chinook and Coho salmon. To address this, remote underwater video and visual snorkel surveys were used to determine the presence and absence of juvenile salmon in paired kelp and no-kelp sites throughout the season when the fish are known to be present in the region. Higher densities of juvenile salmon were detected in kelp-associated areas; however, this effect was detected both before kelp growth in early spring and during kelp presence. Transects conducted on the inner edge of kelp beds, adjacent to rocky shorelines were determined to have the highest salmon densities indicating that physical factors such as substrate type and wave energy associated with these areas may be preferential to juvenile salmon. / Graduate
5

PySciDON: a Python scientific framework for development of ocean network applications

Vandenberg, Nathan 04 January 2017 (has links)
The Salish Sea is a ecologically important coastal region located on the southwest part of British Columbia. Optical measurements were taken using a set of hyperspectral radiometers, the SAS Solar Tracker developed by Satlantic. This sensor is installed on the Queen of Oak Bay ferry, that runs between Nanaimo and Vancouver, as part of the Ferry Ocean Colour Observation Systems (FOCOS) project. We developed a computer program to process the raw sensor data and generate remote sensing reflectance (Rrs) values. This performs similar functions to Prosoft, Satlantic’s own software to process the data. However, we added new features such as an additional preprocessing step to filter the data based on longitude, and new meteorological flag testing and wind speed calculations. The system was tested using Pearson correlation to compare our output with the output from Satlantic Prosoft. Testing helped us identify a few issues, such as adding longitude flags to remove data at the start and end of the trip where the sensor could produce inaccurate results if aiming at land instead of water. Another issue was where the SAS Solar Tracker does not update its pointing angle fast enough when the ferry makes sharp turns and could result in inaccurate data. / Graduate
6

Embodying Landscape: Spatial Narratives of Becoming-Artist on the Islands of the Salish Sea

Jackson, Jolene 20 January 2014 (has links)
Recent literature in cultural geography has turned its attention to the enactment of landscape through performance. Drawing upon the insights of new cultural geography and non-representational theory, this thesis examines the performative enactments of “place” through the production of landscape representations on the Islands of the Salish Sea. In particular, I adopt a narrative approach to consider how the embodied and discursive performances of becoming-artist and the enactment of landscape are co-constituted. Through a comparative case study of four Islands in the Salish Sea – San Juan, Lopez, Salt Spring, and Pender Islands – the current study provides an embodied account of the practices of landscape representation based upon fieldwork, participant observation, and 13 semi-structured interviews with landscape artists on the Islands. This is followed by a thematic analysis of recurring imagery in landscape paintings with a focus on representations of the rural scene, property relations, nationalism, and “unpeopled” landscapes. I conclude that landscape representations are both discursive and experiential in their performative enactments of place. / Graduate / 0366 / jolenejackson12@gmail.com
7

Applications of DINEOF to satellite-derived chlorophyll-a from a productive coastal region

Hilborn, Andrea 10 October 2018 (has links)
A major limitation for remote sensing analyses of oceanographic variables is loss of spatial data. The Data INterpolating Empirical Orthogonal Functions (DINEOF) method has demonstrated effectiveness for filling spatial gaps in remote sensing datasets, making them more easily implemented in further applications. However, dataset reconstructions with this method are sensitive to the characteristics of the input data used. The spatial and temporal coverage of the input imagery can heavily impact the reconstruction outcome, and thus, further metrics derived from these datasets, such as phytoplankton bloom phenology. In this study, the DINEOF method was applied to a three-year time series of MODIS-Aqua chlorophyll-a of the Salish Sea, Canada. Spatial reconstructions were performed on an annual and multi-year basis at daily and week- composite time resolutions, and assessed relative to the original, clouded chla datasets and a set of extracted in situ chla measurements. A sensitivity test was performed to assess stability of the results with variation of cross-validation data and simulated scenarios of lower temporal data coverage. Daily input time series showed greater accuracy reconstructing chla (95.08-97.08% explained variance, RMSExval 1.49 - 1.65 mg m-3) than week-composite counterparts (68.99-76.88% explained variance, RMSExval 1.87 – 2.07 mg m-3), with longer time series of both types producing a better relationship to original chla pixel concentrations (R 0.95 over 0.94, RMSE 1.29 over 1.35 mg m-3, slope 0.88 over 0.84). Original daily chla achieved a better relationship to in situ matchups than DINEOF gap-filled chla, with annual DINEOF-processed data performing better than the multi-year. The results of this study are of interest to those who require spatially continuous satellite-derived products, particularly from short time series, and encourage processing consistency in future DINEOF studies to allow unification for global purposes such as climate change studies (Mélin et al., 2017). / Graduate
8

Bio-optical characterization of the Salish Sea, Canada, towards improved chlorophyll algorithms for MODIS and Sentinel-3

Phillips, Stephen Robert 22 December 2015 (has links)
The goal of this research was to improve ocean colour chlorophyll a (Chla) retrievals in the coastal Case 2 waters of the Salish Sea by characterizing the main drivers of optical variability and using this information to parameterize empirical algorithms based on an optical classification. This was addressed with three specific objectives: (1) build a comprehensive spatio-temporal data set of in situ optical and biogeochemical parameters, (2) apply a hierarchical clustering analysis to classify above-water remote sensing reflectance (Rrs) and associated bio-optical regimes, (3) optimize and validate class-specific empirical algorithms for improved Chla retrievals. Biogeochemical and optical measurements, acquired at 145 sites, showed considerable variation; Chla (mean=1.64, range: 0.10 – 7.20 µg l-1), total suspended matter (TSM) (3.09, 0.82 – 20.69 mg l-1), and absorption by chromophoric dissolved organic matter (a_cdom (443)) (0.525, 0.007 – 3.072 m-1), thus representing the spatial and temporal variability of the Salish Sea. A comparable range was found in the measured optical properties; particulate scattering (b_p (650)) (1.316, 0.250 – 7.450 m-1), particulate backscattering (b_bp (650)) (0.022, 0.005 – 0.097 m-1), total beam attenuation coefficient (c_t (650)) (1.675, 0.371 – 9.537 m-1), and particulate absorption coefficient (a_p (650)) (0.345, 0.048 – 2.020 m-1). Empirical orthogonal function (EOF) analysis revealed 95% of the Rrs variance was highly correlated to b_p (r = 0.90), b_bp (r = 0.82), and TSM concentration (r = 0.80), suggesting a strong influence from riverine systems in this region. Hierarchical clustering on the normalized Rrs revealed four spectral classes. Class 1 is defined by high overall Rrs magnitudes in the red, indicating more turbid waters, Class 2 showed high Rrs values in the red and well defined fluorescence and absorption features, indicated by a high Chla and TSM presence, Class 3 showed low TSM influence and more defined Chla signatures, and Class 4 is characterized by overall low Rrs values, suggesting more optically clear oceanic waters. Spectral similarities justified a simplification of this classification into two dominant water classes – (1) estuarine class (Classes 1 and 2) and (2) oceanic class (Classes 3 and 4) – representing the dominant influences seen here. In situ Chla and above-water remote sensing reflectance measurements, used to validate and parameterize the OC3M/OC3S3, two-band ratio, FLH and, modified FLH (ModFLH) empirical algorithms, showed a systematic overestimation of low Chla concentrations and underestimation of higher Chla values for all four algorithms when tuned to regional data. FLH and ModFLH algorithms performed best for these data (R2 ~ 0.40; RMSE ~ 0.32). Algorithm accuracy was significantly improved for the class-specific parametrizations with the two-band ratio showing a strong correlation to the Chla concentrations in the estuarine class (R2 ~ 0.71; RMSE ~ 0.33) and the ModFLH algorithm in the oceanic class (R2 ~ 0.70; RMSE ~ 0.26). These results demonstrated the benefit of applying an optical classification as a necessary first step into improving Chla retrievals from remotely sensed data in the contrasted coastal waters of the Salish Sea. With accurate Chla information, the health of the Salish Sea can be viably monitored at spatial and temporal scales suitable for ecosystem management. / Graduate / 0416 / stephen.uvic@gmail.com
9

Indigenous and Parks Canada Agency perspectives on the management of Gulf Islands National Park Reserve

Fitzsimmons, Andrew 06 January 2021 (has links)
In the Gulf Islands and Salish Sea Regions of British Columbia the Parks Canada Agency (PCA) currently operates Gulf Islands National Park Reserve (GINPR) and is in the development phase for the proposed Southern Strait of Georgia National Marine Conservation Area Reserve (SSGNMCAR). Protected areas such as these are meant to protect the ecological and cultural heritage of the region on behalf of all Canadians. As the government runs and expands their protected areas in the region it is important to look at their relationship with Indigenous communities in particular, as the PCA mandate requires the agency to work in “partnership” with Indigenous communities (Parks Canada 2017). The region is home to nearly 20 First Nations groups including the three W̱SÁNEĆ First Nations of the W̱SÁNEĆ Leadership Council (WLC). The WLC is an Indigenous government that has publicly stated their perception of a strained relationship with the PCA beginning before the formal establishment of GINPR in 2003. Through historical analysis; interviews with employees from the PCA and members of the W̱SÁNEĆ community; and a review of several aspects of site management and establishment in the region – this thesis explores the changing relationship between the PCA and W̱SÁNEĆ First Nations. Through this thesis I collect and discuss recommendations from W̱SÁNEĆ community members, and develop several myself, for the PCA to consider developing to improve the partnership between the two bodies. Potentially a partnership could lead towards formalized and lasting co-operative decision-making practice in the region’s cultural and natural heritage management. / Graduate
10

Tidal sedimentology and geomorphology in the central Salish Sea straits, British Columbia and Washington State

Mullan, Sean 03 January 2018 (has links)
Intra-archipelago waterways, including tidal strait networks, present a complex set of barriers to, and conduits for sediment transport between marine basins. Tidal straits may also be the least well understood tide-dominated sedimentary environment. To address these issues, currents, sediment transport pathways, and seabed sedimentology & geomorphology were studied in the central Salish Sea (Gulf and San Juan Islands region) of British Columbia, Canada and Washington State, USA. A variety of data types were integrated: 3D & 2D tidal models, multibeam bathymetry & backscatter, seabed video, grab samples, cores and seismic reflection. This dissertation included the first regional sediment transport modelling study of the central Salish Sea. Lagrangian particle dispersal simulations were driven by 2D tidal hydrodynamics (~59-days). It was found that flood-tide dominance through narrow intra-archipelago connecting straits resulted in the transfer of sediment into the inland Strait of Georgia, an apparent sediment sink. The formative/maintenance processes at a variety of seabed landforms, including a banner bank with giant dunes, were explained with modelled tides and sediment transport. Deglacial history and modern lateral sedimentological and morphological transitions were also considered. Based on this modern environment, adjustments to the tidal strait facies model were identified. In addition, erosion and deposition patterns across the banner bank (dune complex) were monitored with 8-repeat multibeam sonar surveys (~10 years). With these data, spatially variable bathymetric change detection techniques were explored: A) a cell-by-cell probabilistic depth uncertainty-based threshold (t-test); and B) coherent clusters of change pixels identified with the local Moran's Ii spatial autocorrelation statistic. Uncertainty about volumetric change is a considerable challenge in seabed change research, compared to terrestrial studies. Consideration of volumetric change confidence intervals tempers interpretations and communicates metadata. Techniques A & B may both be used to restrict volumetric change calculations in area, to exclude low relative bathymetric change signal areas. / Graduate / 2018-12-07

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