Graduate Theses & Dissertations

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Predictive Digital Mapping of Soils in Kitimat, British Columbia
Soil is an essential natural resource that supports provisioning services such as agriculture, silviculture, and mining. However, there is limited knowledge on forest soil properties across Canada. Digital soil mapping may be used to fill these data gaps, as it can predict soil properties in areas with limited observations. The focus of this study was to develop predictive maps of select soil physicochemical properties for the Kitimat Valley, British Columbia, and apply these maps to assess the potential impacts of sulphur dioxide emissions from an aluminum smelter, on soil properties in the Valley. Exchangeable [Ex.] magnesium, organic matter, pH, coarse fragment, Ex. potassium, bulk density, Ex. calcium, Ex. acidity, and Ex. sodium were all mapped with acceptable confidence. Time to depletion of base cation pools showed that ~240 km2 of the study area had a depletion time of 50 years or less. However, sources of base cations such as atmospheric deposition and mineral weathering were not considered. Author Keywords: acidification, buffering capacity, Digital soil mapping, predictive mapping, regression kriging, soil properties
Utilizing Class-Specific Thresholds Discovered by Outlier Detection
We investigated if the performance of selected supervised machine-learning techniques could be improved by combining univariate outlier-detection techniques and machine-learning methods. We developed a framework to discover class-specific thresholds in class probability estimates using univariate outlier detection and proposed two novel techniques to utilize these class-specific thresholds. These proposed techniques were applied to various data sets and the results were evaluated. Our experimental results suggest that some of our techniques may improve recall in the base learner. Additional results suggest that one technique may produce higher accuracy and precision than AdaBoost.M1, while another may produce higher recall. Finally, our results suggest that we can achieve higher accuracy, precision, or recall when AdaBoost.M1 fails to produce higher metric values than the base learner. Author Keywords: AdaBoost, Boosting, Classification, Class-Specific Thresholds, Machine Learning, Outliers
Know*ledge Constellations and Re*constellating
The purpose of this study was to explore the educational implications of a clearer understanding of the practice of using multiple, including Indigenous, knowledges when finding solutions to place-based environmental issues. The impetus for my research came from a growing sense of urgency to address environmental issues within both Indigenous and non-Indigenous communities. Some have argued that communities will be most successful in understanding and resolving such issues if ways can be found to work with different knowledges. However, the practice of bringing together multiple knowledges is not yet consistently effective. At the same time, there is a recognised need for individuals who are able to use different knowledges to address urgent environmental concerns. Unfortunately, there is minimal programming advice based on the perspective of individual practitioners available to guide post-secondary institutions wishing to meet this need. This lead to my first two research questions: What are the key principles and concepts in a narrative describing how individual practitioners think about using knowledges when finding solutions to place-based environmental issues? and What are the implications of this understanding for teaching and learning, especially in post-secondary Indigenous-and-Environmental education? In my project, I used a relational research approach that led to a third question: How is a complexity-inspired interpretive approach suitable for exploring these questions? I had coherent conversations with sixteen practitioners who were deliberately using multiple, including Indigenous, knowledges to find solutions to place-based environmental issues. Practitioners and I co-created a Know*ledge Constellation Story to describe how they think about using knowledges in their work. In a group coherent conversation with five educators who were familiar with Indigenous-and-Environmental education, we explored the educational implications of this story. Together, we finalised a Teaching-Learning Story of Re*constellating and identified ways to prepare students to practice re*constellating, including teaching strategies and program considerations. The Know*ledge Constellation Story and the Teaching-Learning Story of Re*constellating will inform post-secondary Indigenous-and-Environmental education. Graduates from such programs will be better prepared to engage with communities to address environmental concerns, meet legislative and policy requirements, and support research efforts that would benefit from a clearer understanding of the practice of re*constellating. Author Keywords: Complexity-Inspired Interpretive Approach, Conditions of Emergence, Indigenous-and-Environmental Education, Know*ledge Constellations, Principles of Re*constellating, Teaching and Learning
Mythopoeia Sylvatica
Since British colonization of North America and the beginning of Anglo-speaking Euro-Canada and the United States, myth-making or representations of the forests have witnessed degradation and loss of old-growth forest ecosystems or intact sylvan landscapes. Canadian and American versions of the story of the North American Forests shared the same trajectory: forests as ‘wasted-land’ or the sylvan wilderness (terra nullius) divided into properties and cleared to “improve” the land for settlement/agriculture, forests as storehouses for timber and imperial expansion, forest landscapes and specific forest trees as identity politics and sources of industrial and economic power. While forests are recognized according to various stakeholders’ values today, what is commonly accepted as a forest varies widely. The meaning given to “forest” determines related terms and concepts, such as “sustainable forestry” and “reforestation.” This thesis addresses the issue of social-bioecological degradation, loss, and dis(re)membering of old-growth forests and problematizes traditional Western relationships with old wildwoods shaped by notions of space, politics, and economy. In the forest topos, the core question becomes which forest(s) are being imagined, represented, and remembered? Whose environmental imagination is shaping the landscape? As a critical topographical exploration of the North American forests through six witness trees, this thesis demonstrates how the meanings imbued in trees and wild woods come to determine the fate of the forests. It reveals how colonial values and trends persist in our societies still, and calls for an ethical social-ecological reimagining of the forests through traditions of ethical storytelling and environmental witnessing. Author Keywords: critical topography, environmental generational amnesia, environmental witnessing, forests, social-ecological systems, witness trees
Eros noir
The dissertation explores the aesthetic anthropology of Georges Bataille and his collaborators in the Collège de Sociologie, a distinguished group of intellectuals including Roger Caillois, Michel Leiris, Pierre Klossowski, and Walter Benjamin among others. At the dissertation's outset the role, influence, discovery and indeed invention of the Marquis de Sade as the almost mythic prefiguring for so much French aesthetic thought in the period beginning after World War One and up until even the present day is advanced. Before Freud in Vienna, Sade in Paris: the central thematic axis of the following addresses Eros noir, a term for reflecting on the danger and violence of sexuality that Freud theorizes with the "death drive." The deconstruction of the nude as an object and form in particular in the artwork of Hans Bellmer and the writing and art of Pierre Klossowski comprises the latter two chapters of the dissertation, which provides examples of perversion through the study of simulacra and phantasms. The thwarted pursuit of community in the vacated space of Nietzsche's death of a God is a persistent leitmotif of the following in the account it offers of the thought of Georges Bataille and other members of the Collège de Sociologie. Eros noir, at the fatal cusp between ascendant manifest sex and a latent diminished Christianity, underwrites much of the French intellectual contribution to the symbology of cultural modernism. Author Keywords: Bataille, Georges, 1897-1962, Collège de Sociologie, Eroticism, Sade, marquis de, 1740-1814, Surrealism, The Uncanny
Politics of Memory
In dialogue with the critical scholarship on war and remembrance, my research deals with the construction, contestation and negotiation of collective memory in contemporary Vietnam with a focus on commemorations devoted to dead soldiers. Utilizing the methodologies of cultural studies and ethnography, this research seeks to comprehend the politics of memory which characterize collective memory as a social phenomenon whose meanings, interpretations and forms are variedly constructed from a certain social group to the next. Empirically, in this research, constitutive elements of Vietnamese postwar memoryscapes including the hero-centered discourse sanctioned by the Communist Party and the Socialist state, the family remembrance rooted in religious and kinship mandates and the newly emerged online ecology of memory are examined in their own nature as well as in their complicated intertwinements and constant interactions with each other. Case studies and specific methods of individual interview, participant observation and cultural analysis enable the author to approach and identify a wide range of forms and intersections between official and vernacular practices, between oral and living history and institutionalized and cultural presentations of memory. While considering these issues specifically in the Vietnamese context, my dissertation contributes to the increasing theoretical debates in the field of memory studies by exploring the relation of power and the symbolic struggle within and between different social agents involved. As it emphasizes the dynamic and power of memory, this research furthermore situates the phenomenon of collective memory in its dialogues with a broader cultural political environment of postwar society, which is characterized as a hybrid condition embracing processes of nationalism, modernization and post-socialist transformation. Significantly, during these dialogues, as demonstrated in this research, memory works embrace presentism and future-oriented functions which require any social group who is involved to negotiate and renegotiate its position, and to structure and restructure its power. Last but not least it must construct and reconstruct its own versions of the past. Author Keywords: collective memory, Dead soldiers, postwar society, Socialist Vietnam, the politics of memory, war remembrance
Stopover Movement Patterns by Blackpoll and Canada Warblers Across Southeastern Canada During Fall Migration
Stopover ecology is a topic that surges in relevancy as choices made by migrants during stationary periods (stopover sites) may not only have important individuals’ fitness consequences but also can affect population dynamics. I used MOTUS automated telemetry array to study fall stopover duration of Blackpoll Warbler (BLPW) and departure decisions of BLPW and Canada Warbler (CAWA) in relation to various predictors. I affixed radio-transmitters on 55 BLPWs and 32 CAWAs at two banding stations in Ontario in September-October 2014-2015. Radio-tagged individuals were tracked through the MOTUS network across southeastern Canada. I developed models relating age class, fat score, Julian date and stopover movement types to Blackpolls’ stopover duration. I also examined whether there were species-related differences of wind selectivity when resuming migration. No explanatory variable significantly influenced BLPW’s stopover duration. Both species tended to depart under increased tailwind assistance, but with no difference in the effect of wind conditions between the two species. This study provides further evidence supporting the relevance of local wind conditions as a key factor affecting the departure likelihood, especially when migrating birds face an ecological barrier. Author Keywords: Cardellina canadensis, departure decisions, minimum stopover length, MOTUS, overland fall migration, Setophaga striata
Regulation of Cytokinins During Kernel Development in High and Low Yielding Oat and Barley Lines
Cytokinins (CKs) are a family of plant phytohormones responsible for many areas of plant growth and development. There are four free base types of CKs found in higher plants, trans-zeatin (tZ), N6-(∆2-isopentenyl)adenine (iP), cis-Zeatin (cZ) and dihydrozeatin (DZ). CK biosynthesis is regulated by adenosine phosphate-isopentenyltransferase (IPT), which is encoded by a multi-gene family in many plant species. There are two types of IPT pathways responsible for CK production, the tRNA pathway and the AMP (ATP/ADP) pathway. The tRNA pathway putatively produces cZ and the latter predominantly produces iP type nucleotides. CKs have long been studied for their role in stress tolerance, signal transduction, and involvement in many areas of plant growth and development. This study focuses on the role of CKs and CK biosynthesis by IPT during kernel development and comparisons of its regulation in high and low yielding barley and oat lines. The sequence of a putative IPT encoding gene in barley and oat was identified by a blast search of other known IPT gene fragments in closely related species. Quantitative Real time PCR results based on primers designed for the putative barley and oat IPT gene revealed changes in expression of IPT during different stages of kernel development, but no significance difference was associated with yield. Correlation of IPT gene expression in barley with cZ CK profiles measured by HPLC-MS/MS, confirms a putative IPT gene is a tRNA- IPT. HPLC-MS/MS results reveal some CK types, such as benzyladenine, are more predominant in higher yielding lines. This suggests different types of CKs play a role in yield production. Future studies on more IPT genes in the barley and oat IPT gene family will outline a more clear representation of the role of IPT in barley kernel development. Author Keywords: Benzyladenine, Cereal grain, Cytokinin, Isopentenyl Transferase, Mass Spectrometry, Real Time PCR
third wheel
Population cycles are regular fluctuations in population densities, however, in recent years many cycles have begun to disappear. With Canada lynx this dampening has also been seen with decreasing latitude corresponding to an increase in prey diversity. My study investigates the role of alternate prey on the stability of the lynx-hare cycle by first comparing the functional responses of two sympatric but ecologically distinct predators on a primary and alternate prey. I then populated a three species predator-prey model to investigate the role of alternate prey on population stability. My results showed that alternate prey can promote stability, though they are unlikely to “stop the cycle”. Furthermore, stability offered by alternate prey is contingent on its ability to increase intraspecific competition. My study highlights that population cycles are not governed by a single factor and that future research needs to be cognizant of interactions between alternate prey and intraspecific competition. Author Keywords: alternate prey, Canis latrans, functional response, Lepus americanus, Lynx canadensis, Tamiasciurus hudsonicus
Investigation of a Model for Stain Selection and a Robust Estimation for Area of Origin in Bloodstain Pattern Analysis
Bloodstain pattern analysis is fundamental to crime scene investigations by providing insight into the estimation of the area of origin of a blood source. The selection of bloodstains from an impact pattern is the foundation from which the estimation of the area of origin is derived. The purpose of this research was to develop a theoretical model for stain selection and establish a more robust estimation for the area of origin in the analysis of impact patterns. This model was developed by using quantitative data from marked zones on the impact pattern target surface. The minimum distance between the known blood source location and a single bloodstain line of trajectory was calculated for every bloodstain within each pattern investigated. It has been determined that the zone location of a bloodstain is relevant for improving accuracy, and that stains with all alpha angles can be used to calculate an area of origin estimation. Finally, research within this thesis also validated directional analysis and investigated the number of stains that may be required for a precise area of origin estimation. Keywords: Forensic science, Bloodstain, Impact pattern, Bloodstain pattern analysis, Statistics, Forensic Physics
Habitat use and community structure of grassland birds in southern Ontario agro-ecosystems.
Most grassland bird populations are in decline, so it is becoming increasingly important to understand how they use agricultural field types and form their communities. I performed point counts in cultural meadow, intensive agriculture, and non-intensive agriculture areas in 2011 and 2012. Generalized linear models were used to determine the habitat relationships of six focal species. I found that non-intensive agriculture was used most often and intensive agriculture was often avoided, but there were exceptions which indicate habitat use can be species-specific. I determined in which habitats competition was likely occurring and which species pairs were competing in 2011. In 2012, I experimentally tested these relationships by introducing artificial competitors onto sites. By comparing presence-absence data from 2011 to 2012, I found evidence of habitat-mediated interspecific and conspecific attraction involving Bobolink and Grasshopper Sparrow. This research contributes to the current understanding of grassland bird community ecology and conservation. Author Keywords: agriculture, BACI, community ecology, habitat use, species at risk, species interactions
Aeolian Impact Ripples in Sand Beds of Varied Texture
A wind tunnel study was conducted to investigate aeolian impact ripples in sand beds of varied texture from coarsely skewed to bimodal. Experimental data is lacking for aeolian megaripples, particularly in considering the influence of wind speed on ripple morphometrics. Additionally, the modelling community requires experimental data for model validation and calibration. Eighteen combinations of wind speed and proportion of coarse mode particles by mass were analysed for both morphometrics and optical indices of spatial segregation. Wind tunnel conditions emulated those found at aeolian megaripple field sites, specifically a unimodal wind regime and particle transport mode segregation. Remote sensing style image classification was applied to investigate the spatial segregation of the two differently coloured size populations. Ripple morphometrics show strong dependency on wind speed. Conversely, morphometric indices are inversely correlated to the proportion of the distribution that was comprised of coarse mode particles. Spatial segregation is highly correlated to wind speed in a positive manner and negatively correlated to the proportion of the distribution that was comprised of coarse mode particles. Results reveal that the degree of spatial segregation within an impact ripple bedform can be higher than previously reported in the literature. Author Keywords: Aeolian, Impact Ripples, Megaripple, Self-organization, Wind Tunnel

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