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    Evaluating the Conservation Regime for Boreal Caribou in Alberta and Ontario, Canada
    (University of Waterloo, 2026-05-15) Shin, Abby Leilah
    The protection and recovery of species at risk is critical for remediating Canada’s biodiversity crisis. This thesis examines Canada’s legal and policy-based conservation regime as it applies to boreal caribou in Alberta and Ontario. Listed as threatened for decades, boreal caribou continue to experience population declines and habitat degradation despite their significant cultural importance and well-resourced conservation frameworks. As these caribou reflect the overall health of Canada’s boreal landscapes, their precarious status raises broader questions about how federal and provincial conservation efforts perform within areas of natural resource development. This study uses a large-scale literature and policy analysis, a novel evaluation framework, and interviews with eNGO, academic, natural resource, and bureaucratic experts to answer the overarching question: Is Canada’s legislative, regulatory, and policy-based biodiversity conservation regime effectively protecting and recovering boreal caribou in Alberta and Ontario? Findings illustrate how boreal caribou lose out within a complex ecosystem of social, economic, and political priorities. While research and planning for boreal caribou in Alberta and Ontario is relatively robust, tangible outcomes are inhibited by flawed laws and policies which falter upon implementation. Conservation frameworks remain non-committal to habitat protection and disturbance thresholds, whilst being predicated upon uncertain habitat recovery. In Alberta, these challenges are exacerbated by highly subjective land use management, a reliance on intensive predator reduction programs, and severely fragmented caribou ranges. In Ontario, weakening protections are accelerating incoming declines and fragmentation across relatively intact distributions. Overall, this study diagnoses systemic barriers to effective boreal caribou conservation in the two provinces, identifies opportunities for further research, and contributes to the growing empirical evidence for necessary improvements to species at risk governance in Canada.
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    Forage Crop Productivity and Nutrient Use Efficiency on Newly Converted Boreal Podzolic Soils in Central Labrador
    (University of Waterloo, 2026-05-15) Dhindsa, Aman
    Climate change is driving agricultural expansion into Canada’s boreal north, however, the sandy acidic, and nutrient poor Podzolic soils resulting from forest-to-farmland conversion remain severely under studied for their capacity to support crop production. This study evaluated the effects of soil fertility enhancing treatments, including nutrient sources; inorganic mineral fertilizer, organic marine waste (e.g., shrimp compost, shrimp waste, and fish meal), forage biomass incorporation, and liming agents/organic matter inputs; limestone, peat moss, their combination, and biochar, on forage crops (e.g., oat, pea, and oat-pea intercrop). Yields, nutrient uptake, and nutrient use efficiency for N, P and K were evaluated across three boreal farmlands near Happy Valley-Goose Bay, Labrador, Canada. The three farmlands, Birch Lane (BL), Taiga Valley (TV), and Natures Best (NB), differed in conversion history, baseline soil fertility, and management, spanning a gradient from infertile, recently bulldozed mineral soil at TV to a moderately rehabilitated pasture under long‑term agricultural management at BL. Field experiments were conducted over two growing seasons (2023 and 2024) using randomized complete blocks with factorial design (factor 1: nutrient source, factor 2: liming agents/organic matter inputs). Results showed that forage crop yields and nutrient uptake for N, P, and K were influenced by both nutrient sources and liming agents/organic matter inputs applied (p<0.05), with the largest effects seen in the least fertile soils. While treatments were distinct but comparable across the three farms, forage responses were site specific, reflecting the overriding role of inherent soil fertility. In the longer-term managed BL field, inorganic and organic nutrient sources as well as application of limestone with peat, influenced yields, nutrient uptakes and nutrient use efficiencies (p<0.05). At BL, when shrimp compost was applied at similar N rates to the inorganic mineral fertilizer, shrimp compost produced higher yields. At the very recently converted TV, meaningful yields (above 1 t/ha) required the combined application of strong nutrient inputs with organic matter and acidity improving amendments (p<0.05). The application of hardwood biochar at TV, produced the highest yields and nutrient uptakes on the farm when paired with fish meal in the first year. At the intermediate fertility site NB, organic fertilizers, including shrimp compost and shrimp waste, performed similarly to inorganic mineral fertilizer, showing promise as locally useful organic marine waste by-products. Biomass incorporation contributed negligible available nutrients within a single season and did not improve yields above control. Nutrient use efficiency metrics revealed that high efficiencies were not solely a product of experimental soil inputs, but were likely influenced by inherent soil conditions, underscoring the importance of conversion history and cumulative land management on nutrient cycling in boreal agricultural soils. These findings provide evidence that northern boreal farms, such as those in Happy Valley-Goose Bay, can have agronomically meaningful forage crop production (5-7 t/ha) if soil fertility management is matched to site-specific constraints. The conversion history of these lands determines how intensive agricultural management must be to achieve crop productivity. As boreal agricultural development continues to expand in Newfoundland and Labrador and across northern Canada, this study highlights the importance of soil fertility management strategies that consider the interacting roles of nutrient supply, soil acidity, and organic matter status.
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    Development of Molecular-Pore-Containing Polymer Semiconductors via Thermal Side-Chain Cleavage for Enhanced Alcohol Vapor Sensing in Organic Thin-Film Transistors
    (University of Waterloo, 2026-05-15) Papazotos, Jimmy
    This work presents the development of a low detection-limit ethanol vapor sensor, operating as an organic thin-film transistor (OTFT). OTFTs have garnered much attention for their use in gas sensing applications; owing to their low-cost, relatively simple fabrication and ability to be deployed as miniaturized and wearable devices. As such, a series of polythiophenes were synthetized in this work with the aim of being the semiconductive channel material in ethanol vapor sensors. The materials were synthesized with various functionalized side chains – either thermally cleavable or stable in nature. The thermally cleavable sidechains (TCSs) are ester functionalities which can be removed and converted to carboxylic acids upon high temperature post-processing of the devices. The content of TCSs / thermally stable side chains within the polymers in the series were systematically altered to investigate their effect on sensing performance. It was found that complete side chain removal (owing to 100% use of TCSs) totally inhibits sensing performance due to collapse of the film morphology after post-processing. However, including thermally stable side chains in the polymer structure acts as a molecular scaffold and preserves film morphology after TCS removal. This imparts porosity into the thin-film, which facilitates analyte vapor diffusion into the sensing layer and consequently enhances the ethanol vapor sensitivity. A sensitivity increase of ~26% is observed after side chain removal in polymers containing molecular scaffolded structures, proving the formation of stable pores into the polymer films.
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    Anxiety disorder agreement among children with chronic physical illness and their parents
    (University of Waterloo, 2026-05-15) Parks, Reese
    Background: Assessment of child psychopathology using multiple informants provides a more comprehensive and accurate evaluation of child mental health; however, parent-child agreement is low-to-moderate in child psychiatry and tends to be lower for internalizing disorders. Children with chronic physical illness (CPI) are at an elevated risk of developing anxiety disorders, making accurate assessment especially important in this population. Despite this, longitudinal patterns and determinants of parent-child agreement in children with CPI remain underexplored. Objectives: The objectives of this thesis were to: (1) Estimate the magnitude of informant agreement for anxiety disorders on the Mini-International Neuropsychiatric Interview for Children and Adolescents (MINI-KID) between parents and children with CPI at baseline, 6, 12, 24, and 48 months, (2) Explore whether child sex moderates parent-child agreement, and (3) Identify sociodemographic and health factors associated with parent-child disagreement for anxiety disorders on the MINI-KID over time. Methods: Data for 119 dyads came from the Multimorbidity in Youth Across the Life-course (MY LIFE) study, a longitudinal study of children aged 2 to 16 years who had been diagnosed with a CPI and their primary caregiver. The prevalence-adjusted bias-adjusted kappa (PABAK) estimated the magnitude of agreement between parents and children with CPI at baseline, 6, 12, 24, and 48 months. Sex-stratified agreement analyses were conducted using the PABAK to investigate whether parent-child agreement was moderated by child sex. The method of variance estimates recovery (MOVER) was used to construct a confidence interval for the difference in κ estimates between male and female children at each timepoint. A generalized estimating equations model examined factors associated with parent-child disagreement over time. Results: Agreement ranged from fair to substantial over time (κ = 0.40-0.65). For male children, agreement was moderate to almost perfect (κ = 0.47-0.82), whereas for female children, fair to moderate agreement was observed (κ = 0.32-0.51). Moderation by child sex was only found at 6 and 48 months. Compared to baseline, time at 6 months (OR = 0.46, 95% CI = 0.23-0.91, p = 0.026) and 12 months (OR = 0.55, 95% CI = 0.31-0.97, p = 0.040) were associated with lower odds of disagreement. Female children were found to have significantly higher odds of disagreement compared to male children (OR = 2.04, 95% CI = 1.20-3.46, p = 0.008). Parents who were not partnered had lower odds of disagreement relative to partnered parents (OR = 0.27, 95% CI = 0.10-0.71, p = 0.008). Higher levels of parent psychopathology were also associated with increased odds of disagreement (OR = 1.15, 95% CI = 1.01-1.31, p = 0.032). Conclusion: Parent-child agreement ranged from low-to-substantial and varied over time. Moderation by child sex was only evident at 6 and 48 months. Predictors of parent-child disagreement may help identify dyads who may be at greater risk for informant discrepancies. Future research should examine the underlying mechanisms driving parent-child disagreement to inform targeted interventions that help strengthen agreement among parents and children with CPI.
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    Structural and Interfacial Engineering of 2,5-Dihydroxy-1,4-Benzoquinone Coordination-Polymer Cathodes for Sustainable Lithium-Ion Batteries
    (University of Waterloo, 2026-05-14) Wang, Yonglin
    Carbonyl-based organic compounds are one of the most promising sustainable cathode materials for next-generation lithium-ion batteries due to their highly reversible C=O redox center, high theoretical capacity, structural tunability, and potential derivation from abundant or biomass-related feedstocks. However, their practical deployment has been limited by intrinsically high solubility in conventional carbonate- and ether-based electrolytes. Dissolution-driven loss of active material not only leads to rapid capacity fading but also induces serious shuttle effect, self-discharge, and parasitic reactions. Therefore, suppressing dissolution is an essential prerequisite for achieving long-term stability and practical energy density in organic cathodes. Among various carbonyl-based candidates, 2,5-dihydroxy-1,4-benzoquinone (DHBQ) is attractive because of its high theoretical capacity (383 mAh g⁻¹), simple structure, and potential renewability. Yet DHBQ is highly soluble in common organic electrolytes, preventing stable cycling. In this thesis, coordination polymer (CP) synthesis was employed as the primary strategy to reduce the solubility of carbonyl-based cathodes. By incorporating redox-active quinone units into coordination frameworks, CP structures increase the energetic barrier for molecular detachment and solvation, thereby effectively suppressing dissolution. Moreover, CPs can be synthesized through relatively simple coordination reactions using accessible precursors, offering practical feasibility and potential scalability. In Chapter 3, a metastable quinone-based coordination polymer, Co-DHBQ·2H₂O, was investigated as a transition-metal-redox cathode. When cycled between 0.7–3.0 V, the electrodes undergo a reversible four-electron transfer process involving both DHBQ and Co redox reactions. Initial side reactions, including SEI formation and benzene-ring lithiation, lead to a high first-cycle capacity of 783 mAh g⁻¹. After stabilization, the cathode delivers 199 mAh g⁻¹ after 750 cycles, with 84% capacity retention between the 100th and 750th cycles. Structural analyses reveal that coordinated water molecules form strong hydrogen bonds (up to -40.5 kJ mol⁻¹) that stabilize the layered framework and preserve structural integrity during cycling. However, excessive lithiation at low voltages induces structural damage due to the metastable nature of the hydrogen-bonded layers. Comparative studies with anhydrous Co-DHBQ confirm that coordinated water is critical for maintaining structural integrity, enabling reversible Li⁺ accommodation, and achieving long-term electrochemical stability. In Chapter 4, a lithium-based, transition-metal-free Li₂DHBQ cathode was investigated to reduce mass penalty while maintaining low solubility. Although Li₂DHBQ exhibits extremely low solubility in the electrolyte, severe morphological degradation of the active material was identified as the primary origin of poor cycling stability. Repeated lithiation and delithiation induce particle fracture and progressive disruption of electronic percolation pathways, leading to capacity fading independent of dissolution effects. To address this issue, the discharge cutoff voltage was lowered to 0.5 V to promote electrolyte reduction and in situ formation of a protective solid electrolyte interphase (SEI) layer on the Li₂DHBQ surface. This strategy significantly enhanced morphological stability and improved electrochemical performance. When cycled between 0.5–3.0 V at 500 mA g⁻¹, the cathode maintained a capacity of 170 mAh g⁻¹ after 200 cycles, with a low decay rate of 0.16% per cycle. Furthermore, a preconditioning strategy in which the electrode was first cycled at 0.5 V for 20 cycles to form the SEI layer, followed by cycling within the normal 1.5–3.0 V range at 500 mA g⁻¹, resulted in even better performance, retaining 187 mAh g⁻¹ at the 200th cycle. In contrast, a cell cycled only within 1.5–3.0 V retained merely 87 mAh g⁻¹ after 200 cycles. These results demonstrate that controlled SEI formation effectively reinforces morphological stability, mitigates structural degradation, and substantially improves long-term cycling performance once dissolution has been suppressed. In Chapter 5, we build upon Chapter 4 and introduce a more controlled strategy for cathode surface stabilization through the incorporation of fluoroethylene carbonate (FEC) as a CEI-forming additive. The addition of 1 wt.% FEC promotes the formation of a robust CEI layer that significantly suppresses particle pulverization and enhances structural integrity during cycling. SEM and TEM analyses reveal that the optimized CEI layer is relatively uniform and approximately 30 nm thick, effectively mitigating active material degradation. As a result, the Li₂DHBQ cathode with 1% FEC exhibits substantially improved electrochemical performance. When cycled at 500 mA g⁻¹, the electrode retains 185 mAh g⁻¹ after 200 cycles with a low-capacity decay rate of 0.049% per cycle, compared to 81 mAh g⁻¹ and a decay rate of 0.302% per cycle for the FEC-free battery. In addition to enhanced cycling stability, the FEC-containing cell demonstrates superior rate capability, supported by a dominant capacitive contribution of up to 93.7%, indicating accelerated surface-controlled charge storage behavior. These findings confirm that CEI engineering via controlled additive incorporation effectively stabilizes the electrode structure, suppresses interfacial degradation, and optimizes charge storage kinetics once dissolution has been mitigated. The results highlight the importance of interphase design in enabling stable and high-rate organic cathode systems. Beyond electrochemical stability, in Chapter 6 this work also addresses sustainability and end-of-life considerations. A proof-of-concept recycling strategy for Li₂DHBQ-based cathodes was developed using solubility-selective disassembly. By exploiting the solubility contrast among active material, conductive additive, binder, and current collector, approximately 95% of Li₂DHBQ could be recovered under mild conditions. This result highlights the intrinsic compatibility of organic cathode systems with low-energy and environmentally benign recycling pathways. Overall, through coordination polymer immobilization, interfacial engineering, and recyclability-oriented electrode design, this work provides coherent design principles for developing stable, insoluble, and recyclable carbonyl-based cathodes toward sustainable lithium-ion battery technologies.