Graduate Theses & Dissertations

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Question of Space
Chultuns are subterranean chambers that are found throughout the Maya area. The purpose of this thesis is to provide further insight into the function of chultuns, specifically within the area of the Southern Maya Lowlands. Within the Northern Lowlands, the Pre-Columbian Maya used chultuns for water storage, but this function does not appear to be as prevalent within the Southern Lowlands Through reviewing published literature and first-hand excavation, a total of 332 chultuns located with the specified area were catalogued into a database. Based on the information obtained from the research, this thesis has identified the most frequent final function of chultuns, if there is chronological change in final functions of chultuns, and if there is regional change in final functions of chultuns. Author Keywords: burial, chultuns, Maya, ritual, Southern Lowlands, storage
Making eDNA count
Environmental DNA (eDNA) is rapidly becoming an established method for the detection of species in aquatic systems and has been suggested as a promising tool to estimate species abundance. However, the strength of the relationship between eDNA concentrations and taxon abundance (density/biomass) can vary widely between species. I investigated the relationship between eDNA concentration and species abundance using two common and closely-related amphibians in eastern North America, the wood frog (Rana sylvatica) and northern leopard frog (Rana pipiens). I manipulated tadpole density in 80 L mesocosms and documented the relationship between tadpole density, biomass, and eDNA concentration. Species were comparable in biomass but differed in the amount of detectible genetic material produced; density and biomass were the superior abundance metric correlated with eDNA concentration for wood frogs and leopard frogs, respectively. However, increases in eDNA concentration reflected increasing tadpole biomass, therefore biomass is likely a better metric of abundance than density. Overall my findings support that eDNA concentration can be used as an index of species abundance, but that species-specific calibration may be needed before eDNA concentration can be effectively translated to an abundance metric. Future research should refine our understanding of how biotic and abiotic factors influence eDNA production, degradation, and recovery across species, before the method can receive widespread use as a monitoring tool in natural settings. Author Keywords: abundance estimates, environmental DNA, mesocosm, Rana pipiens, Rana sylvatica
Observation-based assessment of atmospheric sulphur surrounding a major aluminum smelter in British Columbia, Canada
Recent developments at an aluminum (Al) smelter in Kitimat, BC resulted in a permitted increase of 27 to 42 tonnes of sulphur dioxide (SO2) emissions per day. Gaseous SO2 is a pollutant known to contribute to acidic deposition through processes of wet and dry deposition and can additionally react in-atmosphere to form particulate sulphate (pSO42-). Between June 2017 to October 2018, an extensive network consisting of ion exchange resin (IER) column, passive-diffusive, and active filter-pack samplers was established to provide an estimate of total annual S deposition and pSO42- variation throughout the Kitimat Valley. Filter-pack sampling determined the relative concentration of pSO42- increased downwind of the smelter. Comparison of observation-based and modelled total annual deposition suggested CALPUFF was accurate in representing the spatial viability of S deposition (R2 = > 0.85). However, the model appeared to overpredict near-field deposition suggesting the potential of underestimation further downwind of the smelter. Author Keywords: aluminum smelter, atmospheric deposition, filter-pack sampler, ion-exchange column sampler, pSO42-, SO2
Seasonal habitat use and movement of native brook trout (Salvelinus fontinalis) in urban headwater streams
Coldwater streams are becoming increasingly impacted due to urbanization. Using environmental surveys, mark-recapture and telemetry, I assessed factors influencing seasonal brook trout (Salvelinus fontinalis) habitat use and movement in urban headwater streams in central Ontario between 2017-18. Generalized additive models were used to assess which habitat variables best explained seasonal yearling and older brook trout abundance, while generalized least squares models were used to assess overall trends in radio-tagged brook trout movement. My research demonstrated dynamic patterns in habitat use and movement by urban stream-dwelling brook trout. Yearlings were primarily influenced by water quality (stream temperature, conductivity), while older brook trout were most strongly influenced by stream morphology (depth, undercut bank). Movement occurred disproportionately around the spawning season and was more limited in the smaller, more altered stream. These findings may be used to inform fisheries managers on crucial timing and location of brook trout habitat refugia within urbanized environments. Author Keywords: Brook trout, coldwater stream, groundwater, habitat use, radiotelemetry, urbanization
Analyzing the Effectiveness of Social Movements Opposing Fossil Fuel Infrastructure
Blocking fossil fuel infrastructure projects like pipelines is increasingly being seen as a legitimate way for civil society groups to reduce global carbon emissions. This research project is an exploratory case study of the Trans Mountain pipeline in British Columbia and its opposition. My research question asks, ‘What has each tactic/strategy of opposition in the campaign to stop the Trans Mountain pipeline expansion accomplished, and how have they been effective? How can they be done more effectively?’ Through interviews and an autoethnography, my research explores the effectiveness of activists in this campaign. I analyze the results of my findings within social movement theory and other activist definitions of effectiveness from my literature review. The more significant findings from my research are that activists need to do a better job educating the public on the issue, need to direct more of their resources towards promoting a solution to the issue and make alliances with other movements and groups. This research project contributes to the literature on the effectiveness of oppositional strategies and tactics of pipeline resistance, as well as social movement theory. Author Keywords: British Columbia, pipeline, protest, strategy, tactic, Trans Mountain
Paleolandscape Reconstruction of Burleigh Bay, Ontario 12,600 cal BP to Present
This thesis presents a palaeotopographic reconstruction of the Burleigh Bay region of Stony Lake (Kawartha Lakes Region, Ontario) from 12,600 cal BP to present. The paleotopographic reconstructions are used to model paleoshoreline locations and archaeological site potential for the Late Paleoindian and early Archaic periods. Isostatic rebound following the end of the last glacial period has altered the topography in the region and water levels are now artificially managed by dams constructed in the 1830s. I completed a high-resolution bathymetric survey using a kayak equiped with a GPS coupled single-beam sonar. Utilizing GIS technology and isostatic rebound response surface models, I created paleotopographic reconstructions for 12,600 cal BP, 11,500 cal BP, 7,000 cal BP, 5,700 cal BP, and present. Results show that water levels in Burleigh Bay have been regressing over time until dam construction. Early site potential is centered in northern inland areas. Site potential following 7,000 cal BP is concentrated in northern areas flooded by the dam. Based on the reconstructions, surveys in lacustrine granite shield regions that follow the Ontario Standards and Guidelines for Consultant Archaeologists risk missing areas of high archaeological potential for early sites in these environments. Paleolandscape reconstructions would alleviate this issue by modeling paleoshoreline changes over time. Author Keywords: Canadian Shield, Early Archaic, Isostatic Rebound, Kawartha Lakes, Late Paleoindian, Paleolandscape
Sustainable Development and Environmental Security in the Canadian Arctic
This study identifies and examines interlinkages between climate change and sustainable development, environmental security, and adaptive capacity through a case study of two communities in the Inuvialuit Settlement Region: Inuvik and Tuktoyaktuk. It seeks to understand how these two communities perceive climate change and define sustainable development, particularly in relation to oil and gas development. This thesis discusses the constraints that may be arising for local communities to benefit from emerging opportunities due to competing notions of sustainable development and environmental security. The findings indicate how notions of environmental security and sustainable development act upon multiple levels to impact the adaptive capacity of communities in the Arctic. The general findings also suggest that regionally specific understandings of sustainable development, sustainability, and environmental security need to be acknowledged in order to develop successful governance coordination and cooperation strategies and paradigms related to economic, social, infrastructure and environmental issues in the NWT and the Canadian Arctic. Author Keywords: Arctic, Beaufort Sea, climate change, Environmental Security, Inuvialuit, Sustainable Development
Lives of Young Delinquents
The Royal Philanthropic Society (RPS) was the first institution in England to care for young offenders. While historians have demonstrated the legal importance of this institution, none have examined the experience of the youths it attempted to reform. The admission registers of the RPS reveal the importance of adults and peers in the experiences of the inmates of the institution, as both could be sources of conflict and support. Youths could express power over their own lives by resisting the authority of adults, but also by conforming to the rules of the RPS. Inmates could restrict the choices of their peers by working with the RPS, but also through peer pressure or violence. Networks of collaboration and youth culture could also exert a positive impact on peers. Because this thesis represents male youths as actors, it makes a significant addition to recent histories emphasizing the impact of the subaltern groups on eighteenth-century reform movements. Author Keywords: Conformity, Juvenile Delinquency, Penal Reform, Power Relationships, Royal Philanthropic Society, Youth Culutre
Effects of Invasive Wetland Macrophytes on Habitat Selection by Turtles
Invasive species that alter habitats can have significant impacts on wildlife. The invasive graminoids Phragmites australis (Cav.) Trin. ex Steud, hereafter Phragmites, and Typha × glauca Godr. are rapidly spreading into North American wetlands, replacing native vegetation. Invasive Phragmites is considered a potential threat to several species-at-risk (SAR), including some turtle species. My study wetland contained large stands of Phragmites, as well as Typha spp. (including invasive T. × glauca) that have similar structural traits to Phragmites. To explore the hypothesis that Phragmites and Typha spp. do not provide suitable habitat for turtles, I tested the prediction that turtles avoid Phragmites- and Typha-dominated habitats. I used VHF-GPS transmitters to follow Blanding’s turtles (Emydoidea blandingii, n = 14) and spotted turtles (Clemmys guttata, n = 12). I found that both turtle species did not avoid Phragmites- or Typha-dominated habitats when choosing a home range, or while moving within their home range. I also tested whether the microhabitat selection of Blanding’s turtles and spotted turtles is affected by shoot density of Phragmites, Typha spp., or both. I compared shoot densities of Phragmites and Typha spp. in 4 m2 plots, from locations used by tracked turtles with paired, random locations in these turtles’ home ranges. For both turtle species, the densities of Phragmites and Typha shoots were comparable between used and random locations within the home ranges (generalized linear mixed model; p > 0.05). The use of Phragmites- and Typha-dominated habitats by Blanding’s turtles and spotted turtles suggests that these habitats do not automatically constitute “unsuitable habitats” for turtles. Phragmites and Typha spp. (especially T. × glauca) can replace preferred habitats of some turtle species, and the control of these invasive macrophytes can help to preserve habitat heterogeneity. However, the presence of SAR turtles in Phragmites and Typha spp. stands should inform risk-assessments for invasive plant species control methods that include mechanical rolling of stands, where heavy machinery might encounter turtles. Author Keywords: Blanding’s turtles, compositional analysis, habitat selection, Phragmites australis, spotted turtles, Typha x glauca
Genomic architecture of artificially and sexually selected traits in white-tailed deer (Odocoileus virginianus)
Understanding the complex genomic architecture underlying quantitative traits can provide valuable insight for the conservation and management of wildlife. Despite improvements in sequencing technologies, few empirical studies have identified quantitative trait loci (QTL) via whole genome sequencing in free-ranging mammal populations outside a few well-studied systems. This thesis uses high-depth whole genome pooled re-sequencing to characterize the molecular basis of the natural variation observed in two sexually selected, heritable traits in white-tailed deer (Odocoileus virginianus, WTD). Specifically, sampled individuals representing the phenotypic extremes from an island population of WTD for antler and body size traits. Our results showed a largely homogenous genome between extreme phenotypes for each trait, with many highly differentiated regions throughout the genome, indicative of a quantitative model for polygenic traits. We identified and validated several potential QTL of putatively small-to-moderate effect for each trait, and discuss the potential for real-world application to conservation and management. Author Keywords: evolution, extreme phenotypes, genetics, genomics, quantitative traits, sexual selection
"Changing our community"
Community-based research (CBR) is a method of discovery that can provide pragmatic methods of advocating for and enabling community change. CBR literature and practice has focused on securing educational and job skills training outcomes for students rather than the communities, and community outcomes CBR and partnership frameworks were truly meant to serve. This research evaluates the effectiveness of a research brokering organization, and the community outcomes that can be meaningfully related back to established partnerships and research. A linked contribution and realist evaluation were employed to consider the contributions of U-Links Centre for Community-Based Research to capacity building in Haliburton County, for host organizations, local municipalities and the public. A community survey (n=65), interviews with past project hosts and management committee members (n=26) anecdotal project exploration, internal document review, and participant observation from living in the region and working within the organization, offers qualitative and quantitative data to support this contribution narrative, while also theorizing key factors for developing projects with high contribution potential. Five key factors were found which can act as both contexts and mechanisms of community-based research mobilization: relevance, relationships, resources, rigour and reach. Author Keywords: capacity building, community, community-based research, contribution analysis, evaluations, research impact
Cluster Approach Applied to the One-Dimensional Anderson-Hubbard Model
S. Johri and R. Bhatt developed a real-space renormalization group approach aimed at extracting the localized single-particle eigenstates of the Anderson model from a large system by identifying clusters of resonant site potentials. E. Campbell generalized this real-space renormalization group approach using standard perturbation theory. Both approaches were intended to approximate the single-particle density of states of the Anderson model. In this thesis, we aimed to test the potential of applying a similar real-space renormalization group approach to calculate the density of states of the interacting Anderson-Hubbard model. Our interest in the density of states of this model is due to a V-shaped zero-bias anomaly in two-dimensional systems. A real-space renormalization group approach is best applied to a one-dimensional system. We found that the zero-bias anomaly is not V-shaped in one-dimension. To test the potential of a real-space renormalization group approach, we used the cluster approach which is the same as the non-interacting renormalization group approach but without the perturbation theory and found that for strong disorder this technique could accurately calculate the density of states over a wide range of energies but deviated from exact results at the band edge, at $\omega=\pm U$ and near $\omega=0$. The first two inaccuracies will be reduced with a proper real-space renormalization group approach. We suspect that the last inaccuracy is associated with long range physics and may be difficult to recover. We also developed a technique that adjusts the identification of clusters in the cluster approach to improve the computation time of the density of states with minimal loss of accuracy in a tunable range around the Fermi level. We found that this technique significantly reduced the computation time and was able to preserve the density of states near the Fermi level, except at the smallest energies near $\omega=0$. Author Keywords: Anderson-Hubbard model, renormalization group, Strong electron correlations, Zero-bias anomaly

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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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1974 - 2024
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