Graduate Theses & Dissertations

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Trace Metal Geochemistry in Peatlands
Peatlands can be found widely across all latitudes and play a significant role in global cycles within the earth’s biosphere. The anoxic conditions in peatlands promotes the accumulation of organic matter through decreased rates of decomposition and the storage of certain elements, which have received contaminant loading over the course of human existence, with significant increases occurring during the period of industrialization. We assessed global patterns of metal enrichment in peatlands in 439 cores distributed across 5 continents and 21 countries and measured 35 elements by depth increments and by peatland type. Global patterns in enrichment factors (EF’s) were determined for all metals with the majority of metals being found to have a median EF < 2 indicating relatively minor enrichment. Principal component analysis indicated EF’s of 6 metals (Cd, Co, Cu, Ni, Pb, and Zn), 2 metalloids (As and Sb) and Se in the upper peat horizon had similar spatial patterns among peatlands and these elements had generally the highest EF’s with many cores exceeding EF >10 and some having EF values >100. Significant differences in EF’s were found for these 9 “pollution” elements by peatland type and to a greater extent by geographic region, with higher EF values typically occurring in Europe and North America. Enrichment factors for most elements exhibited weak but significant positive correlations with modelled [1850 – present] S deposition. Estimated pools for the “pollution metals” within the 0 - 40 cm depth varied considerably, with median global pools in peat ranging from 12.9 mg m-2 (Sb) to 439 mg m-2 (Zn) for these 9 metals. Climate changes presents a significant risk to global peatland geochemistry due to expected changes in hydrologic regimes, resulting in potentially increased metal mobility though drought-induced peatland acidification, with historic areas previously impacted by industrial activities presenting the greatest risk of metal release to downstream receiving environments. Using a case study, we examined the impact of simulated 30-day drought on pore water chemistry at six sites in a peatland complex in Elliot Lake Ontario that were historically impacted by uranium (U) mining activities. All sites responded similarly to simulated drought with pore water pH significantly declining. The decline in pore water pH was likely due to increasing sulphate (SO42-) concentrations, which accompanied large increases in Al, Ni, Cu, Pb, Zn, and U. Dissolved organic carbon (DOC) increased, which may further enhance Al, Cu, and U mobility as these metals are strongly complexed by organic acids. Metal partitioning (Kd) values could be significantly predicted by pH and DOC although the strength of the relationship varied considerably among sites. Multiple linear regression and the inclusion of SO4-2 improved predictions, indicating that declines in pH as a result of SO4-2 and H+ production primarily governs metals and U partitioning in peatland soils. The results from both studies show that metal enrichment in global peatlands is highly variable, with northern peatlands in industrialized areas presenting the greatest risk of metal release to downstream surface waters based on expected hydrologic impacts from climate change due to historical and on-going metal and S deposition. Author Keywords: Acidification, Climate Change, Drought, Enrichment Factors, Global, Peatlands
Tracking Mercury and Mercury Stable Isotopes Throughout the Wabigoon/English River System
In the Wabigoon/English River system, mercury concentrations downstream from Dryden, ON, where there was a former chlor-alkali plant, remain elevated in sediments and biota. Understanding the current extent and severity of mercury contamination downstream from the former chlor-alkali plant is of great interest in furthering the clean-up of mercury within the traditional territory of Asubpeeschoseewagong Netum (Grassy Narrows) First Nation. The objective of this study was to evaluate the current level and extent of mercury contamination within sediments, crayfish, Hexagenia mayflies, yellow perch, spottail shiner and walleye in the Wabigoon/English River system. An additional objective was to use mercury stable isotope analysis to distinguish between legacy mercury from the former chlor-alkali plant and mercury from geogenic sources. Mercury contamination within surface sediments and biota at locations as far as 178 kms downstream of the historical source of mercury contamination are elevated relative to the reference lake, Wabigoon Lake. Isotope ratios in young of the year fish and sediments collected from within the system were distinct from fish from the reference lake, Wabigoon Lake, indicating that anthropogenic mercury contamination is distinguishable from geogenic mercury. Author Keywords:
Transcendental Turn
This dissertation traces the concept of transcendentalism from Kant's Critique of Pure Reason (1781) to Michel Foucault's historical a priori and Pierre Bourdieu's field and habitus, with implicit reference to Deleuze's `transcendental empiricism,' and the influence this trajectory has had on contemporary theory and culture. This general conceptual framework is used as the basis for a critical analysis of a series of examples taken from popular culture to highlight their transcendental conditions of possibility and the influence this conceptual paradigm has had on today's theory. The examples include the NFL `concussion crisis,' South Park's problematization of the discourse surrounding it, as well as the literature of Charles Bukowski, as an exemplification of an immanent writer-written situation. It is further suggested that, not only is transcendentalism an epistemological framework for thought, but it also doubles as an ontological principle for the emergence of a constitutively incomplete and unfinished reality. Author Keywords: Bukowski, Concussion, Foucault, Kant, South Park, transcendental
Tłı̨chǫ, Co-management and the Bathurst Caribou Herd, 2009-2011
Since time immemorial caribou have been and remain central to Tłı̨chǫ life and culture. As early as the late 19th century, Canada began to implement wildlife management policies in the NWT in response to concern over the health and future of caribou populations. However, the 2005 Tłı̨chǫ Land Claims and Self-Government Agreement (Tłı̨chǫ Agreement) signed by the Tłı̨chǫ, the Government of the Northwest Territories and the Canadian Government outlines that Tłı̨chǫ will have a say in wildlife management on Tłı̨chǫ Lands. Co-management is the power-sharing model used in an effort to ensure that the Tłı̨chǫ voice is heard in these decisions. My thesis centres on the 2009-2011 co-management process and the resulting final management decisions regarding monitoring and management actions to promote the stabilization and recovery of the Bathurst Caribou herd. I focus my analysis on the Tłı̨chǫ perspective as expressed during this co-management process. I conclude that while Tłı̨chǫ perspectives were presented in the hearings and related processes, they were not well represented in the final management actions. This omission speaks to the wider issue of how aboriginal people are treated and understood in Canada. Author Keywords: Canada, Caribou, Co-management, Northwest Territories, Tłı̨chǫ
USE OF SALIVARY CORTISOL TO EVALUATE THE INFLUENCE OF RIDES ON THE STRESS PHYSIOLOGY OF DROMEDARY CAMELS (CAMELUS DROMEDARIUS)
Many facilities attempt to alleviate the risk of chronic stress in captivity by providing environmental enrichment shown to minimize behavioural disorders and stress in several species. One potential form of enrichment used in zoos is training animals to perform rides for guests, however, the effect of this activity on the welfare of individual animals has never been examined. I validated the use of saliva for assessing stress in dromedary camels (Camelus dromedarius) an animal commonly used for rides. I then measured variation in salivary cortisol in four male camels during animal rides for guests at the Toronto Zoo. The camels were sampled during the ride season (from June to August) using four treatments: 1) in their pasture, 2) at the ride area not performing rides, 3) performing a low number of rides (n=50/day) and 4) performing a high number of rides (n=150/day). Furthermore, samples were taken before and after the ride season for comparison. There was a significant difference between the post-ride season treatment and the three treatments involving guest presence during the ride season (ride area, low rides, high rides. This indicates that performing rides is not a stressful experience based on the stress metrics I used, and suggests that rides may be a form of enrichment for dromedary camels. Author Keywords: ACTH challenge, animal welfare, camels, environmental enrichment, salivary cortisol, stress
UV-Curable hybrid sol-gel materials
This thesis describes the synthesis, application and evaluation of a UV crosslinked 3-methacryloxypropyltrimethoxysilane-derived coating formulation. This is a two-component sol-gel system with 3-methacryloxypropyltrimethoxysilane (MaPTMS) and tetraethoxysilane (TEOS). Herein we show that if we change the co-solvent required for solubilizing MaPTMS from the more common methanol and ethanol to isopropanol we change the rate of hydrolysis from days or weeks to minutes. With the assistance of 2D 29Si-NMR we demonstrate that the system undergoes extensive condensation in twenty minutes. Using standard UV irradiation, the material can be extensively UV crosslinked with 70% of the methacryloxy functionality being consumed in 5 minutes upon irradiation in the presence of a photo-initiator. When this material is used to coat low carbon steel and immersed in an accelerated corrosion solution (dilute Harrison’s solution); this material affords low carbon steel 25 hours of protection when crosslinked and 17 hours of protection when uncrosslinked. The material was then used to encapsulate polyaniline (PANI), an intrinsic conductive polymer used in the corrosion protection of metal substrates. PANI has been encapsulated previously in sol-gel material, but due to the pH dependence of the solubility of PANI, it can not be encapsulated in more commonly chemically crosslinked sol-gel. As our system is UV crosslinked rather than chemically crosslinked, we were able to successfully demonstrate the inclusion of PANI into our coating system. Finally, this thesis includes a thorough computational investigation into the structure and band gap of PANI. Through the analysis of the band gap it was shown that the structure of the polymer commonly displayed in literature is not the correct structure of the polymer. Our results suggest that when PANI is made electrochemically, the oligomer contains two quinoid units next to one another instead of the more usually represented regularly alternating benzoid and quinoid units. The results also suggest that when PANI is made using the oxidant ammonium persulfate, the polymer most likely contains a Michael adduct structure somewhere in the polymer chain which dominates PANI’s electronic properties. Author Keywords: 3-Methacryloxypropyltrimethoxysilane, Computational Chemistry , Corrosion , Polyaniline, Tetraethoxysilane
Unbridled Potential
Recently, equine assisted learning (EAL) has emerged as a novel approach to building resiliency competencies in at-risk youth. This mixed-methods study presents evaluation results for an 8-week community-based EAL program with 83 young women (age 13-18 years) with a history of interpersonal trauma. Analyses examined changes in self-reported mental health symptoms (posttraumatic, depression) and resiliency factors (sense of mastery, sense of relatedness, emotion regulation) from pre- to post-test and at 1-month and 6-month follow-ups. Changes in outcomes were also correlated with intervention processes (attendance, session ratings) to see if program experiences were associated with differential outcomes. Results showed that EAL has potential in improving resiliency outcomes, at least for those participants who derived greater satisfaction and value from the sessions. Many improvements were sustained over the long term. Participants’ qualitative feedback provided insight into their subjective experiences and highlighted the unique role that horses played in the EAL process. Author Keywords: Emotion Regulation, Equine Assisted Learning, Experiential Learning, Resilience, Sense of Mastery, Sense of Relatedness
Uncovering the Barriers to Sustainable Music Consumption
The study sought to uncover the motivations influencing collectors when they buy recorded music. These motivations were analyzed through the lenses of environmental, economic, and cultural sustainability. Trent Radio Programmers were interviewed because of their frequent use of recorded music, sizable collections, and active participation in the local music scene. The study identified disconnects between artist, industry, and consumer motivations that hinder the achievement of a sustainable system. Environmental sustainability was not considered, while the artists’ economic and cultural sustainability were. This finding translates to the idea that in the music industry, to strengthen cultural sustainability, economics must be supported, which requires environmental impact. This research has the potential to catalyze critical conversations about digital media, artist welfare, and the state of the music industry. Author Keywords: College Radio, Cultural Sustainability, Economic Sustainability, Environmental Sustainability, Music Collecting
Underdevelopment in Eastern Bechuanaland
This thesis offers a comprehensive look at the changing roles of a colonial built railway in what is now eastern Botswana. It was built for the extraction of mineral wealth and migration of cheap African labour in Southern Africa but it later assumed a different role of shaping the modern Botswana state. The thesis deals with several other issues related to the railway in Bechuanaland including land alienation, the colonial disregard of the chiefs’ authority, racial discrimination and the economic underdevelopment of Bechuanaland. Since there were no other significant colonial developments at the time of independence, this thesis argues that the railway was the only important feature of the British colonisation of Bechuanaland. From early on, the railway attracted different cultures, identities and religions. It was also instrumental in the introduction of an indigenous capitalist class into Bechuanaland. Author Keywords: Bechuanaland, Botswana, colonisation, migration, railway, underdevelopment
Understanding Angler Dynamics in a Recreational Lake Trout (Salvelinus namaycush) Fishery in Algonquin Provincial Park Using Long-Term Access Creel Data
In order to effectively manage recreational fisheries, it is important to understand how the resource is being used. In this thesis, long-term creel census data, collected on Lake Opeongo in Algonquin Provincial Park, Ontario, Canada was used to assess fine-scale angler dynamics within a recreational Lake Trout (Salvelinus namaycush) fishery. The spatial distribution of angler reported catch locations of Lake Trout within the lake, was assessed using an Optimized Hotspot Analysis in ArcGIS. Areas of significant clustering of catch locations were revealed during all time periods and varied in size and location both seasonally and temporally. Cormack-Jolly-Seber models were used to evaluate the probability of individual angling boats persisting in the regional fishery and being detected on Lake Opeongo through time, as well as to examine the effect of angler travel distance and gas prices on participation parameters. Time-varying models revealed that the probability of an angler persisting in the fishery varied, while detection estimates remained stable. Travel distance had a negative effect on both parameters while increased gas prices only had a slight negative effect on detection estimates. Additionally, among Lake Opeongo anglers, angling avidity varied as did lake specific fishing experience. Average CUE was found to be higher among angling parties who visited the lake more often than fishing parties who visited relatively few times. Author Keywords:
Understanding Dimensions of Environmental Sustainability in a Northern Indigenous Context
Although the concept of environmental sustainability has become increasingly popular, the literature offers little practical guidance to direct priorities or actions to support environmental sustainability in northern Indigenous communities. A case study in Hopedale, Nunatsiavut, and a systematic literature review was undertaken to understand: 1) what aspects of the local environment are of value to a northern Indigenous community; and 2) what does existing literature identify as key elements of a community-based approach to monitor valued aspects of the environment in a northern Indigenous context. Hopedale residents spoke to the importance of going off on the land and identified a number of categories of places in their local environment of importance to them, including: 1) valued areas for human-use, 2) areas to protect, 3) areas of environmental concern, and 4) areas to monitor. The systematic literature review highlighted trends on community-based monitoring (CBM) publications, and identified key 13 elements of CBM approaches that are pertinent to northern Indigenous communities. Insights from this study will inform environmental planning and management in the case community of Hopedale, as well as offer guidance to enhance current and future CBM activities in the North and elsewhere. Author Keywords: community-based monitoring, environmental sustainability, Inuit, Labrador, participatory mapping, systematic literature review

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Format: 2023/02/02