Graduate Theses & Dissertations

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Managing Through Change
Arctic ecosystems are increasingly altered by climate change, and some wildlife species, like moose, are adapting to these new conditions. Indigenous knowledge and values, such as those held by Inuit, can provide insight into adaptive wildlife management and may improve ecosystem resiliency. This thesis seeks to address the following question: What is the potential role of Indigenous knowledge in managing wildlife under climate change? This thesis follows a qualitative exploratory design involving 1) a systematic literature review of the peer-reviewed literature and 2) a case study on moose in Nunatsiavut in which 35 interviews and participatory mapping were conducted with Inuit beneficiaries. The results demonstrate a range of potential roles for Indigenous knowledge and values in managing species impacted by climate change. The case study of moose in Nunatsiavut has applicability across the Canadian Arctic where the sustainability of harvested species is at risk. Author Keywords: Arctic, climate change, Indigenous knowledge, moose, Nunatsiavut, wildlife management
Surface temperature regulation during stress exposure
The influence of stress exposure on the body temperature of vertebrates has been known for nearly two-thousand years. While the proximate mechanisms supporting this phenomenon are well described, the ultimate mechanisms remain enigmatic. In this thesis, I propose a novel hypothesis which states that changes in body surface temperature (henceforth "surface temperature") following stress exposure occur to reduce energetic expenditure toward thermoregulation, thus freeing energy for use in the stress response (hereafter, the "Thermoprotective Hypothesis"). Using a paired experimental design, I first show that black-capped chickadees (Poecile atricapillus, Linnaeus, 1766) exposed to repeated stressors decrease their surface temperatures at low ambient temperatures, and increase their surface temperatures at high ambient temperatures relative to unstressed controls. These changes in surface temperature contribute to a relative reduction in heat loss in the cold, and a relative increase in heat dissipation in the warmth among stress-exposed individuals, thus reducing their energetic demands toward more costly thermoregulatory strategies. Next, I show that stress-induced changes in surface temperature are most pronounced in chickadees that experience naturally-occurring resource-restrictions, suggesting that this response occurs to balance allocation of energy among the stress response and thermoregulation (i.e. a true energetic trade-off ). Third, I show that the magnitudes of chronic, stress-induced changes in surface temperature are highly variable among, and highly consistent within, chickadees, therefore suggesting that this response could hold adaptive significance if such variation among individuals is heritable. Finally, using domestic pigeons (Columba livia domestica, Gmelin, 1789) as a model species, I show that stress-induced changes in surface temperature are highly pronounced at bare tissues with a critical role in thermoregulation for some avian species (the bill), when compared with responses at surrounding bare tissues (the eye region). Together, these findings strongly support the Thermoprotective Hypothesis and suggest that endotherms may trade energetic investment toward thermoregulation with that toward the stress response in resource-limiting environments. Author Keywords: heat transfer, infrared thermography, stress physiology, surface temperature, thermoregulation, trade-off
Drink my beer, smoke my weed, my good friends are all I need
Past research has predominately supported an association between insecure attachment and substance use. More recent research has found that while individuals with secure attachment may use substances, they do so with less risk. The current study attempted to replicate the finding regarding secure attachment and substance use and examined the motivational drives behind why students use substances. A total of 318 undergraduate students completed self-report questionnaires examining peer attachment, alcohol and marijuana use, as well as motivations for use. Results indicated that students who reported low frequency use of alcohol or marijuana did not have significantly higher security ratings compared to students who reported increased use. Additionally, although hypothesized, secure attachment ratings were not associated with social facilitation or enhancement motivations. However, fearful and dismissing attachment ratings were both significantly associated with coping motives as predicted, while preoccupied and fearful attachment ratings were significantly associated with conformity motives. Lastly, results from multiple regressions suggest that coping and enhancement motivations are significant predictors of alcohol use, while enhancement motivations are marginally significant in predicting marijuana use. Author Keywords: alcohol, attachment, marijuana, motivation
Calcium Stress in Daphnia Pulicaria and Exposure to Predator-Derived Cues
In recent decades, declining calcium concentrations have been reported throughout lakes across the southern edge of the Canadian Shield. This raises concern as Daphnia populations have shown to be decreasing as they require calcium not only for survival but to mitigate predation risks. Therefore, the purpose of my thesis was to study the adaptability of Daphnia under calcium limitation and predation risk from Chaoborus. Firstly, I examined the effects of calcium limitation and Chaobours kairomones on daphniid life-history and population growth. I found that low calcium concentrations and Chaoborus kairomones affected Daphnia calcium content, life-history traits, and survival. Next, I focused on how calcium concentrations and Chaoborus abundance affected the calcium content and abundance of daphniids. During this study, I also examined the relationship between the abundance of Daphnia and a competitor Holopedium. I found that calcium concentrations and the abundance of Chaoborus affects daphniid abundance. Overall, results from this study show the importance of considering both predation risk and calcium declines to better determine daphniid losses. Author Keywords: anti-predator responses, Chaoborus, competition , Life-History traits, predator cues, Zooplankton
An Exploration of Partnership Models for Urban Conservation Land Management in Ontario
Partnerships for management of public parks have a long history, but little attention has been given to the current models of partnerships during a period of municipal austerity in Ontario. Using a qualitative assessment of transcripts from representatives of 10 municipal partner groups, this research considers what some of the current models are, the impact that they may have, and how municipalities may foster these partnership arrangements. The participating organizations demonstrated that their governance models evolved to suit their mandate, activities, and scope of interaction with their municipality. Additionally, this research corroborates past findings that efficacy of an organization is tied to their ability to partner with other agencies and act as a capacity amplifier. These results demonstrate how municipal conservation partnerships can be effectively applied to create enhanced financial outcomes and improved community engagement, while delivering community based environmental programming. Author Keywords: Conservation, Environmental Stewardship, Municipal Management, Partnership, Social Ecology, Urban Parks
Morphology, Production and Trade
The Africana IIA, an amphora subtype of the Africana II class, was produced in Africa Proconsularis (the present-day Tunisian Sahel) during the mid-Roman Imperial period (from the late 2nd c. A.D. to the middle decades of the 3rd c. A.D.), and was distributed around the western Mediterranean. Scholars have noted meaningful morphological variations on this subtype’s rim but had overlooked the information that these rims may convey. The preliminary analysis of the variations found on Africana IIA amphora rims yielded possible connections to various production sites or regions, distribution samples, and/or consumption sites, and suggested that at least some of the rim variants were indicative of origin. The rim variants also seemed to correlate to different trade routes, and potentially, different trade mechanisms, including private versus State interests. Author Keywords: Africa Proconsularis, Africana IIA amphora, ancient economy, Byzacena, ceramics, fabric analysis
Characteristics of Models for Representation of Mathematical Structure in Typesetting Applications and the Cognition of Digitally Transcribing Mathematics
The digital typesetting of mathematics can present many challenges to users, especially those of novice to intermediate experience levels. Through a series of experiments, we show that two models used to represent mathematical structure in these typesetting applications, the 1-dimensional structure based model and the 2-dimensional freeform model, cause interference with users' working memory during the process of transcribing mathematical content. This is a notable finding as a connection between working memory and mathematical performance has been established in the literature. Furthermore, we find that elements of these models allow them to handle various types of mathematical notation with different degrees of success. Notably, the 2-dimensional freeform model allows users to insert and manipulate exponents with increased efficiency and reduced cognitive load and working memory interference while the 1-dimensional structure based model allows for handling of the fraction structure with greater efficiency and decreased cognitive load. Author Keywords: mathematical cognition, mathematical software, user experience, working memory
Examining Strategies of New Public Management in Homelessness Policy
This research is a critical analysis of coordinated access as an approach to addressing homelessness focusing on Peterborough, Ontario as a case study. This study is situated in scholarship that explores the presence of strategies of New Public Management in social service and healthcare delivery. Balancing the methods of Smith’s (2005) Institutional Ethnography and Bacchi’s (2009) What is the Problem Represented to Be approach I investigate the way that Federal, Provincial and Municipal homelessness policies organize themselves as instruments of power and I connect this analysis to the accounts of staff working within the homelessness response system. I discover the frame of vulnerability through which homelessness is addressed to be an individualizing mechanism that facilitates the downloading of responsibility for social welfare to local governments without adequate resources. I argue that the consequence of an under resourced system is that only the most extreme forms of suffering can be addressed, and the tools used to decipher who is most vulnerable do not account for structural inequalities. Author Keywords: Coordinated Access, Homelessness, Homelessness Policy, Institutional Ethnography, Neoliberalization, New Public Management
Nassau Mills Complex
The objective of this thesis is to develop and implement a heritage plan for the Nassau Mills Complex, a locally-significant Euro-Canadian historical site that operated on what is now Trent University’s campus in Peterborough, Ontario. Within the framework of public archaeology and Cultural Heritage Management (CHM), emphasis is placed on the importance of protecting the site and its historic remains in order for present and future generations to appreciate and enjoy. Data was gathered by way of field and archival research, as well as through consultations with various archaeological and museological professionals. Of particular concern is evaluating how the Complex is significant to Peterborough, how it should be commemorated, public engagement and the importance of information accessibility, and the potential issues that may arise as a result of this project. In addition, recommendations regarding how the site and its collections should be preserved and presented to the collective society are also examined. Author Keywords: Cultural Heritage Management, Nassau Mills Complex, Peterborough, Preservation, Public Archaeology, Trent University
Changes in the Representations of Women from the 1980s Turkish Cinema to New Turkish Cinema
The thesis examines the changes in the representations of women in Turkish cinema from the 1980s through the 2000s in terms of semiotic codes. To demonstrate the shifts of the representations of women over three decades, four films directed by two representative filmmakers of the 1980s and the 2000s are analyzed within the context of gender codes: A Sip of Love (Atıf Yılmaz/1984), The Night, Angel and Our Gang (Atıf Yılmaz/1994), The Third Page (Zeki Demirkubuz/1999) and Envy (Zeki Demirkubuz/2009). Using gender as code in deconstructing women’s characteristics and their representations in the films, the research highlights the structural image of women in the semiotic sense. The stereotypical representations in Turkish cinema question social norms, patriarchy, and Islamic norms in Turkey. Author Keywords: Gender codes, Islam, Patriarchy, Semiotics, The representations of women , Turkish cinema
influence of tree species litterfall on soil chemistry and implications for modelling soil recovery from acidification
Decades of acidic deposition have depleted base cation pools in soil over large parts of eastern north America, including the Muskoka-Haliburton region of central Ontario. This region has also experienced a shift in forest species composition over the past 200 years, favouring sugar maple (Acer saccharum Marsh.) at the expense of species such as white pine (Pinus strobus L.) and eastern hemlock (Tsuga canadensis (L.) Carr.). This shift in species composition may have changed soil chemistry over time due to differences in nutrient and metal inputs in litterfall. An analysis of litterfall and soil chemistry was conducted for five tree species commonly found across central Ontario. Stands were established in the Haliburton Forest & Wild Life Reserve and were dominated by one of balsam fir (Abies balsamea (L.) Mill.), eastern hemlock, white pine, sugar maple, or yellow birch (Betula alleghaniensis Britt.). Analysis of mineral soil oxides suggested that these stands were established on similar parent material. Deciduous dominated stands (maple and birch) had greater litterfall mass compared with conifer stands (fir, hemlock, and pine), generally leading to greater macronutrient inputs to the soil. Elemental cycling through the organic horizons was more rapid in deciduous stands, with base cations having the shortest residence times. This suggests that a change from greater conifer dominance to mixed hardwood forests may lead to more rapid elemental cycling and alter the distribution of elements in soil. Forests in the region are typically mixed and the resulting differences in soil chemistry may influence model predictions of soil recovery from acidification. Laboratory leaching tests indicated that both stand type and the acidity of simulated rainwater inputs influenced soil solution chemistry, with deciduous stands generally having a greater buffering capacity than sites dominated by coniferous species. Changes in soil chemistry were examined for each stand type using the Very Simple Dynamic (VSD) biogeochemical model. Simulations showed that soil base saturation began to increase following lows reached around the year 2000, and similar patterns were observed for all stands. When sulphur (S) and nitrogen (N) deposition were held constant at present rates, soil base saturation recovery (toward pre-1900 levels) was marginal by 2100. With additional deposition reductions, further increases in base saturation were minor at all sites. In conjunction with additional deposition reductions, the elimination of future forest harvesting allowed for the greatest potential for recovery in all stands. Overall, these results suggest that changes in forest cover may influence soil chemistry over time, most notably in the organic soil horizons. However, forecasted recovery from acidification is expected to follow similar patterns among stands, since differences in soil chemistry were less significant in the mineral soil horizons which compose a greater proportion of the soil profile. Author Keywords: base cation decline, forest harvesting, litterfall, mineral weathering, soil acidification, VSD model
Short photoperiod lowers visceral adiposity and shifts the molecular clock in Peromyscus leucopus
The length of photoperiod can alter circadian rhythms and change fat depot mass whencombined with environmental temperatures below thermoneutral. To isolate photoperiod effects, we compared the effects of long and short photoperiod exposure at thermoneutrality in photoperiod sensitive, F1 generation adult male white-footed mice (P. leucopus). Mice were housed in long-day or short-day photoperiod conditions at thermoneutrality for 4 weeks. Short photoperiod decreased vWAT mass without changing body weight, scWAT or iBAT mass, or calorie consumption. Short photoperiod increased Adrβ3 and Lpl mRNA expression in vWAT with no change in Ucp1, Pgc1a or Hsl. vWAT Per1, Per2 and Nr1d1 mRNA expression were aligned to the onset of dark and food intake, while Bmal1 and Clock were misaligned. These findings suggest that short photoperiod per se can decrease visceral fat accumulation, without activating thermogenesis, reinforcing that environmental photoperiod should be considered when researching cause and prevention of obesity. Author Keywords: adiposity, circadian rhythm, clock genes, obesity, Peromyscus, photoperiod

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Graduate student theses produced at Trent University. You may also browse theses and dissertations by year, program, or author.

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