Geography - Theses, Dissertations, and other Required Graduate Degree Essays

Receive updates for this collection

Towards a suburban spatial epidemiology: differentiating geographical patterns of cancer incidence, patient access, and surgical treatment in Canada’s urban fringe

Date created: 
2016-11-18
Abstract: 

Epidemiological studies have traditionally categorised study populations as urban or rural. However, a growing proportion of the global population resides in spaces that are neither dense urban cores nor rural/remote regions. These interstices are distinctly suburban, featuring a low density of services, poor walkability, and spatial isolation relative to their urban counterparts. Contrary to the dominant imaginary of the affluent ‘American Dream’, Canada’s suburbs are increasingly becoming home to socioeconomically deprived populations. Following from the well-established links between socioeconomic status and health geographies, this dissertation presents quantitative geographical evidence that the suburbs differ from their urban and rural counterparts, constituting a third, epidemiologically distinct space. The first substantive chapter provides an introductory tracing of the suburb’s socioeconomic history, laying the contextual foundation for a distinct categorisation. The following three chapters then draw upon this categorisation to differentiate spatial epidemiological patterns of cancer along both urban/suburban/rural and socioeconomic axes. The second chapter uses exploratory temporal mapping to document a recent emergence of oral cancer cases in British Columbia’s suburbs, geographically coincident with immigration from betel quid-chewing regions and an increase in local socioeconomic deprivation. The third chapter then explores head and neck cancer patients’ spatial access to cancer treatment centres across the province, highlighting significantly greater travel times among the most deprived suburban and rural populations. The fourth chapter evaluates whether these spatial and socioeconomic disparities reflect actual treatment rates, focussing on resection surgeries for five cancer types across Canada, excluding Québec. Resection rates were positively associated with socioeconomic deprivation in rural areas and inversely associated in urban areas, while the highest overall rates were observed in middle-SES suburban populations. Drawing upon these three cancer studies, this dissertation proposes a suburban spatial epidemiology, in which suburbs are differentiated from urban and rural spaces. I conclude by asserting that the suburbs’ unique placial contexts merit standalone attention in health research, calling for further examination of suburban spaces in epidemiological research.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Nadine Schuurman
Department: 
Environment: Department of Geography
Thesis type: 
(Thesis) Ph.D.

Effects of bigleaf maple on the growth and morphology of mature conifers in the southern coastal forests of British Columbia.

Date created: 
2016-11-22
Abstract: 

The influence of bigleaf maple (Acer macrophyllum) on the growth of mature conifers in the coastal forests of British Columbia has not been previously assessed. I used a paired plot design to evaluate the influence of mature bigleaf maple on the growth and morphology of Douglas-fir (Pseudotsuga menziesii) and western hemlock (Tsuga heterophylla). Twelve conifer plots including bigleaf maple trees in the center (BLM) were paired with twelve plots that had only conifers present (DF). For the Douglas-fir and western hemlock growing in these plots, the diameter at breast height (DBH), height, age, volume, canopy morphology, site index, stand basal area, tree density and competition index were compared using paired-t tests between BLM and DF plots. Cores taken from Douglas-fir and western hemlock trees were used to assess growth chronologies; and radial growth rates and basal area increment (BAI) were compared between BLM and DF plots. There were no significant differences in tree height, tree age, site index or competition index for both Douglas-fir and western hemlock, and DBH for Douglas-fir, when compared between BLM and DF plots. DBH was greater for western hemlock in BLM as compared to DF plots. Both Douglas-fir and western hemlock that were growing next to bigleaf maple had significantly higher radial growth rates and BAI than Douglas-fir and western hemlock surrounded by conifers only. BLM plots did not have a different standing wood volume (total or conifer-only) than DF plots. My findings suggest that the inclusion of bigleaf maple in conifer stands could enhance biodiversity without negatively affecting timber production.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Margaret Schmidt
Department: 
Environment: Department of Geography
Thesis type: 
(Thesis) M.Sc.

Seasonal Methane Dynamics in Lakes of the Mackenzie River Delta, Western Canadian Arctic

Date created: 
2016-08-22
Abstract: 

Methane (CH4) dynamics were investigated in lake-waters of the Mackenzie River Delta in 2014 and 2015 to estimate CH4 emissions and evaluate potential drivers of seasonal CH4 dynamics. Water-column CH4 and related variables were measured at end-of-winter and tracked through open-water in up to 43 lakes, plus water-column CH4 oxidation (MOX) and water-to-atmosphere emissions were measured in 6 lakes. Under-ice CH4 accumulations were high by end-of-winter, with levels in some lakes greater than 20 years prior. Water-column CH4 and carbon-quantity are positively related regardless of season, however, relationships between CH4 and carbon-quality are strikingly different between winter and open-water. CH4 is inversely related to pH, which, surprisingly, also negatively affects MOX. MOX is highest at ice-out and decreases over open-water. Based on areal-weighted fluxes, Mackenzie Delta lakes emitted 35.79 Gg of CH4, with 24% occurring at ice-out, and during open-water 50% and 26% respectively occurring via ebullition and diffusion.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Lance Lesack
Department: 
Environment: Department of Geography
Thesis type: 
(Thesis) M.Sc.

Reducing harm through food and work: incorporating food security and peer employment in harm reduction programming

Date created: 
2016-09-06
Abstract: 

Food is usually provided in harm reduction settings, like needle exchanges, low-barrier shelters, and drug consumption rooms. These spaces are often staffed by people who use drugs (PWUD) and/or living with HIV/AIDS (PLWHA) who serve their peers. Yet, there is little comprehensive discussion of how food and peer work fit into organizations with a harm reduction orientation (OHRO) for low-income PWUD/PLWHA. Drawing on 27 semi-structured interviews with OHRO in Greater Vancouver, Canada, this thesis explores the variegated regional landscape of food, peer work, and harm reduction using literatures on harm reduction, poverty management, the shadow state, and foodscapes. Results demonstrate that OHRO are important nodes in low-income PWUD/PLWHA foodscapes, but that they do not systematically integrate food programming with their harm reduction philosophies. Similarly, peer employment is widespread, but organized in ways that can compromise harm reduction goals. I conclude with recommendations to improve food access, and employment for PWUD/PLWHA.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Eugene McCann
Department: 
Environment: Department of Geography
Thesis type: 
(Thesis) M.A.

The place of geographic information and analysis in global health: A case of maternal health in regions of southern Mozambique

Date created: 
2016-08-26
Abstract: 

Maternal ill-health is a major global health burden, responsible for approximately 350000 deaths every year. While this is a very high figure considering that most maternal deaths are avoidable, it represents close to a 45% reduction in maternal death rates from 1990, and is a largely the result of successful clinical strategies that were pioneered through the Millennium Development Goals. However, emerging strategies in global maternal health now acknowledge the broad nature of the socio-cultural and environmental determinants associated with maternal health, and call for multi-sectoral approaches to complement the dominant clinical perspectives. While there is mounting evidence on the importance of the social determinants of health, there are multiple challenges associated with identifying, measuring and taking action on the context specific determinants of health.This dissertation posits that some of the techniques that have been developed in the discipline of health geography offer potential to address these challenges. The objectives of this dissertation were to implement geographic methods for identifying and measuring the context relevant determinants of maternal ill-health, and to elucidate the place specific characteristics of associations between these social determinants and maternal health outcomes. The thematic premise of this dissertation was partly determined through extensive exploration of literature on what is known concerning the use of geographical information systems in maternal health. The core empirical work supporting this dissertation was completed in the southern region of Mozambique and addressed the objectives through both qualitative and quantitative exploration, identifying community perceptions of these determinants and validating them using geostatistical methods. Key data challenges concerning the use of geographical analysis are also addressed. Chiefly, this dissertation contributes a suite of methods that demonstrate how to measure the social determinants of maternal health. While this research was conducted in Mozambique and addresses maternal health, the geographic approach highlighted in this work could be used to understand other health concerns and in different places.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Nadine Schuurman
Department: 
Environment: Department of Geography
Thesis type: 
(Thesis) Ph.D.

Longitudinal subglacial bedform semi-automated mapping and measurement

Date created: 
2015-05-25
Abstract: 

This thesis addresses methodological issues in the morphometric inventorying of relict drumlins and mega-scale glacial lineations (longitudinal subglacial bedforms, LSBs) which pose limits to a robust description of LSB morphometry and thus to testing hypotheses of LSB genesis, with implications for postdicting past, and predicting future, ice sheet behavior. Focus is on a) the adequacy of previously used morphometric measurement methods (MMM) (GIS) and b) the development of LSB semi-automated mapping (SAM) methods. Dimensions derived from an ellipse fitted to the LSB footprint based on Euler’s approximation are inaccurate and both these and orientation based on the longest straight line enclosed by the footprint are imprecise. A newly tested MMM based on the standard deviational ellipse performs best. A new SAM method outperforms previous methods. It is based on the analysis of normalized local relief closed contours and on a supervised ruleset encapsulating expert knowledge, published morphometric data and study area LSB morphometry.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Tracy Brennand
Department: 
Environment:
Thesis type: 
(Thesis) M.Sc.

Exploring the influences on the Caribbean's emerging medical tourism industry

Date created: 
2016-04-25
Abstract: 

Governments and hospitals worldwide have increasingly expressed interest in ‘medical tourism’, where medical treatments are privately purchased by foreign visitors seeking non-emergency care. There is steady discussion worldwide about the development of medical tourism, including countries with volumes of health service exports that are currently very small. Caribbean countries are no exception. In a region not well known for its medical tourism destinations (excepting Cuba and Costa Rica), there are regular announcements of numerous new private hospital proposals and public initiatives to create policies and incentives to support the development of the sector. While a relatively new area of research, medical tourism has received a great deal of attention in low and middle income countries that are known to attract patients from high income countries. This has resulted in a considerable body of literature that retrospectively examines its economic and health system impacts of medical tourism in ‘successful’ destinations, often using secondary data. This has resulted in a great deal of work examining medical tourism that has focused on limited number of countries and hospitals with established volumes of health services exports, particularly Thailand, Malaysia, and India. Little is known about the perspectives and factors that are prospectively driving interest in medical tourism worldwide, nor their attendant implications for the health systems of countries attempting to market their medical services internationally. This dissertation examines the development of the medical tourism industry in the Caribbean to prospectively explore how and why the sector is being promoted there at this time. Primarily focused on analyses of qualitative data collected from fieldwork conducted in the small island Caribbean states of Barbados and Jamaica in 2011-2013, the dissertation also incorporates semi-structured interview data from a larger study of medical tourism in Mexico, Guatemala, and Barbados from 2013-2014 to identify parallel processes and factors driving the contemporary development of medical tourism throughout the Greater Caribbean in order to better understand and articulate their health equity implications for the health systems of the region.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Valorie Crooks
Department: 
Environment: Department of Geography
Thesis type: 
(Thesis) Ph.D.

Social enterprise in British Columbia: the profile page as a crisis heterotopia

Author: 
Date created: 
2016-04-04
Abstract: 

Social enterprises in British Columbia now labour online on social media websites through profile pages. The online profile pages of senior staff in British Columbian social enterprises revealed regional and localized links to Cartesian workplaces in British Columbia following statistical analysis. A network of senior staff profile pages within these data was analysed and found to be influenced by the material deprivation and urbanity of Cartesian social enterprise workplaces and also the category of a social enterprise. Ten year-long studies then looked at the online Facebook pages of social enterprises highlighted in the analysis of professional networks. Facebook pages reached cities that their senior staff members were connected to in their professional network, and social enterprise Facebook pages were accessed primarily by women throughout the year. Thirteen semi-structured interviews about profile pages were analysed and theorised as Foucauldian heterotopias that 1): allow social enterprises to experience a crisis in targeted communication in a networked non-place that offers control; 2) allow smaller social enterprises to experience a crisis in time and resources.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Peter Hall
Department: 
Environment: Department of Geography
Thesis type: 
(Thesis) M.A.

Spatial Influences of Heat Exposures and Social Vulnerability on the Temperature-Mortality Relationship: A Case Study in the Greater Vancouver Area

Author: 
Date created: 
2016-04-04
Abstract: 

Climate change has increased the frequency and intensity of extremely hot weather. The health risks are not uniform across affected areas due to variability in heat exposure and social vulnerability, but these differences are challenging to map with precision. Therefore, this PhD research evaluated the uses of linear and nonlinear statistical models to map the intra-urban difference of temperature distribution, compared the temperature distributions mapped from land surface temperature, air temperature, and apparent temperature (Humidex), and developed a spatially- and temporally-stratified case-crossover approach for delineation of areas with higher and lower risk of mortality on extremely hot days, and applied this framework in greater Vancouver, Canada. A digital elevation model, Landsat 5 TM, Landsat 7, and MODIS water vapor products were used to map the air temperature and Humidex. Records of all deaths with an extremely hot day as a case day or a control day were extracted from an administrative vital statistics database spanning the years of 1998-2014. Three heat exposure and eleven social vulnerability variables were assigned at the residential location of each decedent. Conditional logistic regression was used to estimates the odds ratio for a 1°C increase in daily mean temperature from a fixed site for subsets of the data above and below different values of the spatial variables. An important result was that intra-urban variability in air temperature and Humidex could be mapped using a Random Forest model with good accuracy (RMSE = 2.31°C and 2.04°C respectively). This project also found that Humidex could better demonstrate the spatial distributions of heat exposure when it was compared with the temperature maps from land surface temperature and air temperature. Also, the heat exposure and social vulnerability variables with the strongest spatially-stratified results were Humidex and labour nonparticipation rate. Areas at higher risk had values ≥3.7°C warmer than Vancouver International Airport, the reference site, and ≥60% of the population neither employed nor looking for work. These variables were combined in a composite index to quantify their interaction and enhance visualization of high-risk areas. In conclusion, methods from this PhD research provided a data-driven framework for spatial delineation of the temperature-mortality relationship by heat exposure and social vulnerability. Results can be used to map and target the most vulnerable areas for public health intervention, and the methodology is directly transferable to other cities in Canada and abroad.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Nadine Schuurman
Anders Knudby
Department: 
Environment: Department of Geography
Thesis type: 
(Thesis) Ph.D.

Refining the pattern and style of deglaciation on the southern Fraser Plateau and environs

Date created: 
2015-09-03
Abstract: 

The Cordilleran Ice Sheet (CIS) represents an ideal paleo-analogue for studying the pattern and style of deglaciation across an area of moderate relief. Hypotheses tested on the CIS landscape may be applied to our understanding of the processes involved in modern deglaciation. This thesis addresses current shortcomings in our understanding of the pattern and style of CIS deglaciation over the southern Fraser Plateau in south-central British Columbia (BC). During the last glacial buildup, ice advancing from mountain ranges in the east and west met somewhere over the southern Fraser Plateau (Tipper 1971a), forming an area of significant ice accumulation, according to models of glacioisostatic rebound (Fulton and Walcott 1975, Johnsen and Brennand 2004), and potentially increasing in thickness to form an ice divide during glacial maximum (Wilson et al. 1958). Deglaciation through ice stagnation and downwasting has been hypothesized for the plateau (Fulton 1967, 1976, 1991). This thesis tests the hypothesis that the lateglacial landform and sediment record supports the large-scale regional stagnation of the CIS over south-central BC.Through the integration of aerial photographs, digital elevation models, field observations of landform morphology, stratigraphy and sedimentology, and shallow geophysics (electrical resistivity tomography, ground-penetrating radar) a map of lateglacial landforms and lakes associated with deglaciation of the last CIS is produced. Ice-marginal indicators, including ice-marginal lake systems and moraines are used to reconstruct ice-marginal positions, demonstrating retreat from southeast to northwest across the southern Fraser Plateau. Fields of pristine glaciotectonic moraines indicate active retreat rather than passive melting of plateau ice. Analysis of morphosedimentary relationships of esker systems and associated glacier hydrology demonstrates ice retreat was characterized by low-sloping thin ice where ice-dammed lakes were important for meltwater storage. Crevasse-fill ridges and eskers formed in ice-walled canyons record areas of localized ice stagnation.

Document type: 
Thesis
Senior supervisor: 
Tracy Brennand
Department: 
Environment: Department of Geography
Thesis type: 
(Dissertation) Ph.D.