Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Phytohormones, Cytokinin (CK) and Abscisic acid (ABA), are best known for controlling plant growth and stress responses; but they also mediate various developmental perspectives in alga. Yet, their mode of action in algal adaptive strategies to heavy metal responses, their involvement in orchestration of phytohormone crosstalk remain largely unknown and a molecular framework of… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Owen Sound Bay, which is located within the traditional territory of the Saugeen Ojibway Nation (SON), is contaminated as a result of historical industrial and shipping activity. Gross contamination of the sediments in the inner part of the Bay (i.e., Owen Sound Harbour) includes high concentrations of polycyclic aromatic hydrocarbons (PAHs) and other organic compounds, as well as metals… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>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… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>In endotherms, physiological functioning is optimized within a narrow range of tissue temperatures, meaning that the capacity to dissipate body heat is an important parameter for thermoregulation and organismal performance. Yet, experimental research has found mixed support for the importance of heat dissipation capacity as a constraint on reproductive performance. To investigate the… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Sudbury, Ontario is an epicenter of research on industrially degraded landscapes. Regreening efforts over the past 40 years have changed the landscape, leading to an increase in forest cover in the "barrens", that once covered more than 100,000 ha. This study characterized changes in plant and insect composition using a space for time approach in the pine plantations. A total… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>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")… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Recent agricultural land use change in east-central Ontario, including the expansion of intensive agriculture (corn and soybean crops) and tile drainage (TD) infrastructure, may alter the fluxes of both phosphorus (P) and nitrogen (N) to the Lower Great Lakes. Through intensive monitoring of several sub-watersheds that encompassed a range of row crop and TD extents, this study examined… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Martchenko, Daria, Thesis advisor (ths): Shafer, Aaron B. A., Degree committee member (dgc): Freeland, Joanna R., Degree committee member (dgc): Davy, Christina M., Degree committee member (dgc): Kyle, Christopher J., Degree granting institution (dgg): Trent University Abstract: <p>Evaluating the impact of climate change is arguably one of the main goals of conservation biology, which can be addressed in part by studying the demographic history of species in the region of interest. In North America, landscape and species composition during the most recent Pleistocene epoch was primarily influenced by glaciation cycles. Glacial advance and retreat caused species… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Many emerging infectious diseases are caused by pathogens that possess free-living life stages, in which they interact with the environment directly rather than through the mediation of a host. These diseases represent major impediments to wildlife conservation; however, the dynamics of their interaction with the environment are poorly studied, often due to the difficulty of detecting… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>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… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Anthropogenic activities such as human activity and livestock grazing are responsible for the global rise in disturbance impacts on wildlife and may underlie regional changes in biodiversity and ecosystem dynamics. Few studies have tried to disentangle the effects of different anthropogenic activities on wildlife behaviour, leaving a major gap in our understanding of conservation and… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Macrophytes play an important role in aquatic ecosystems, and thus are integral to ecological risk assessments of environmental contaminants. In this dissertation, I address gaps in the assessments of contaminant fate and effects in macrophytes, with focus on glyphosate herbicide use for invasive plant control. First, I evaluated the suitability of Typha as future standard test species… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Giardia intestinalis possesses four isotypes of cytochrome b5 (gCYTB-I-IV) that differ from their mammalian counterparts, suggesting different functions in this protozoan parasite. Although the recently discovered Giardia flavoenzyme, GiOR-1, reduces these cytochromes, its properties have not been thoroughly studied, owing to the difficulty in its expression. Here I describe successful… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The integration of genetic and environmental information can help wildlife managers better understand the factors affecting a species' population structure and their response to disturbance. This thesis uses genetic techniques to assess the broad and fine scale population structure of mountain goats in Alaska. The first chapter aims to determine the number of genetically distinct… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Bhargav, V Vikram, Thesis advisor (ths): Dorken, Marcel MD, Thesis advisor (ths): Freeland, Joanna JF, Degree committee member (dgc): Bowman, Jeff JB, Degree committee member (dgc): Shafer, Aaron AS, Degree granting institution (dgg): Trent University Abstract: <p>Heterosis, expressed as phenotypic superiority over parental species, typically peaks in first generation hybrids (F1s), while later generations (F2 +) exhibit lower fitness. The decrease in hybrid fitness is called hybrid breakdown. The overall incidence of hybrid breakdown in invasive hybrid zones remains poorly understood. The Laurentian Great Lakes (LGL) region contains a hybrid zone… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The emergence of fungal hybrid pathogens threatens sustainable crop production worldwide. To investigate hybridization, the related smut fungi, Ustilago maydis and Sporisorium reilianum, were selected because they infect a common host (Zea mays), can hybridize, and tools are available for their analysis. Hybrid dikaryons exhibited filamentous growth on plates but reduced virulence and… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Genetic variation is the raw material and basis for evolutionary changes in nature. The loss of genetic diversity is a challenge many species are facing, with genomics being a potential tool to inform and prioritize decision making. Whole genome analysis can be an asset to conservation biology and the management of species through the generation of more precise and novel metrics. This… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Transactive response (TAR) DNA-binding protein of 43 kDa (TDP-43) pathology, including fibrillar aggregates and mutations, develops in amyotrophic lateral sclerosis (ALS) and is characterized by hyperphosphorylation and aggregation patterns, a mechanism largely understudied. In addition, ALS remains without a cure. Herein, in vitro aggregation of phosphorylated TDP-43 was explored, and… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The onset of neurodegenerative diseases such as Alzheimer's disease (AD) and amyotrophic lateral sclerosis (ALS) are typically characterised by the aggregation of protein biomarkers into cytotoxic fibrils. Novel means of analysing these biomarkers are needed to expand the literature toward earlier diagnosis of these conditions. Electrochemical sensors could offer the sensitivity and… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Identifying population declines and mitigating biodiversity loss require reliable monitoring techniques, but complex life histories and cryptic characteristics of anuran species render conventional monitoring challenging and ineffective. Environmental DNA (eDNA) detection is a highly sensitive and minimally invasive alternative to conventional anuran monitoring. In this study, I… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Euglena gracilis is an enigmatic and adaptable organism that has great bioremediationpotential and is best known for its metabolic flexibility. The research done in this
dissertation addresses (1) how growth conditions impact cellular composition, and (2)
how chemometric approaches (such as statistical design of experiments and artificial
neural networks) are viable alternatives to the… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The Hudson Bay region is a sensitive environment, where anthropogenic (e.g., dams, diversions, and/or reservoirs) impacts have increased in recent decades, potentially influencing the functioning of the ecosystem. Dissolved organic matter (DOM) entering Hudson Bay comes from both terrestrial (allochthonous) and aquatic (autochthonous) sources. The chemical composition of DOM is important… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): McDonough, Andrew Michael, Thesis advisor (ths): Watmough, Shaun A, Degree committee member (dgc): Aherne, Julian, Degree committee member (dgc): Hutchinson, Tom, Degree committee member (dgc): Sager, Eric, Degree granting institution (dgg): Trent University Abstract: <p>In this study we seek to better understand the potential effects of short-term (5-year) N fertilization on jack pine forest biogeochemistry, vascular plant community composition and to project a temporal endpoint of nitrogen leaching below the major rooting zone. Aqueous ammonium nitrate (NH4NO3) was applied above the forest canopy across five treatment plots (20 x 80 m) four times… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Lake of the Woods (LOW) is a large international waterbody which suffers from frequent and widespread algae blooms. Previous studies have highlighted the importance of the lake's largest tributary, the Rainy River (RR) and its significance in total phosphorus (TP) delivery to the LOW. Unfortunately, little is known about TP contributions from the RR and its tributaries within the… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>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… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>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… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>In Canada, eastern flowering dogwood (Cornus florida L.) is an endangered tree that occurs only in the Carolinian forest of southern Ontario. Threats to this species include habitat fragmentation and the fungal pathogen dogwood anthracnose (Discula destructiva). I conducted a population genetic analysis using seven nuclear microsatellite markers to determine if fragmented populations are… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Soil and tree chemistry were measured across 15 limed sites that were established 14 to 37 years ago within the Sudbury barrens in Ontario, along with two unlimed pre-treatment condition reference sites and an unlimed remnant pine forest. Soil pH and base cation (calcium (Ca), magnesium (Mg), and potassium (K)) concentrations were elevated in surface organic [FH] horizons up to 37-years… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>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… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Grich, Nourhene, Thesis advisor (ths): Emery, Neil NE, Degree committee member (dgc): Saville, Barry BS, Degree committee member (dgc): Morrison, Erin EM, Degree committee member (dgc): Donaldson, Michael MD, Degree granting institution (dgg): Trent University Abstract: <p>The oyster mushroom, Pleurotus ostreatus, is one of the most widely cultivated edible basidiomycetes. It has gained increased attention for its economic, environmental, and medicinal properties. While a lot is known about cytokinins (CKs) and their actions at the molecular and cellular levels in plants, much less is known about the function of CKs in other kingdoms. Cytokinins, which… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Johannessen, Cassandra, Thesis advisor (ths): Metcalfe, Chris D, Thesis advisor (ths): Parnis, J. Mark, Degree committee member (dgc): Metcalfe, Chris D, Degree committee member (dgc): Parnis, J. Mark, Degree committee member (dgc): Dang, Huy, Degree committee member (dgc): Hickie, Brendan, Degree granting institution (dgg): Trent University Abstract: <p>Road runoff is a vector for the transport of potentially toxic chemicals into receiving waters. In this study, selected tire-derived chemicals were monitored in surface waters of rivers adjacent to two high traffic highways in the Greater Toronto Area in Ontario, Canada. Composite samples were collected from the Don River and Highland Creek in the GTA during 5 hydrological events that… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Opioid drugs are among the microcontaminants that are discharged with domestic wastewater into the aquatic environment with the potential to affect the development and reproductive capacity of aquatic organisms. To study the effects of exposure of fish to opioid drugs, Japanese medaka (Oryzias latipes) were exposed over a full life cycle to environmentally relevant (i.e. ng/L)… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Fleming, Kaitlyn Julia, Thesis advisor (ths): Beresford, David V, Thesis advisor (ths): Schaefer, James A, Degree committee member (dgc): Smith, M. Alex, Degree committee member (dgc): Abraham, Kenneth F, Degree granting institution (dgg): Trent University Abstract: <p>Basic biogeographic information is lacking for many species, such as where species are found, and how they dispersed there. Using ground beetles collected during 2008-2015 from across northern Ontario and Akimiski Island, Nunavut, I present new information on ground beetle distribution in this eastern Nearctic boreal forest, including 2 first Canadian records, 9 first provincial and 48… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Assessments of the adaptive potential of natural populations are essential for understanding and predicting responses to environmental stressors like climate change and infectious disease. The range of stressors species face in a human-dominated landscape, often have contrasting effects. White-tailed deer (Odocoileus virginianus, deer) are expanding in the northern part of their range… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>As wild turkeys (Meleagris gallopavo silvestris) move farther north, informed management decisions are critical to support the sustainability of this reintroduced species. We tracked roost tree selection and patterns of the network of roost trees, for wild turkeys, over 2 years in Peterborough, ON, using GPS and VHF transmitters. Wild turkeys showed preference for taller and larger roost… more