Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Due to climate change and managed care, birds may face interacting effects of novel diets and environmental temperatures. I examined how captive zebra finches (Taeniopygia guttata) responded to a 6-month acclimation to either thermoneutral or cool temperatures when provided with saturated or unsaturated fatty acid enriched diets. Body mass was lower on the unsaturated fatty acid diet,… more
Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Animals are essential to freshwater biogeochemistry and productivity. Through their excretion, aquatic consumers release bioavailable nutrients and carbon that can vary with animal taxonomic rank, trophic position, and abiotic factors such as light and nutrient supply. In fresh waters, light and nutrient supply is often modulated by dissolved organic matter (DOM), a "murky"… more
Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Phosphorus is the growth-limiting nutrient in freshwater environments. Dissolved organic phosphorus (DOP) refers to phosphorus within dissolved organic matter (DOM). Much of DOP is bioavailable, but it is poorly understood due to its complexity. This thesis explores the export DOP to Lake Erie from its tributaries, by investigating its speciation and concentration seasonally through… more
Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Knight, Caitlyn, Thesis advisor (ths): Kapron, Carolyn, Degree committee member (dgc): Tobin, Stephanie, Degree committee member (dgc): Huber, Robert, Degree committee member (dgc): West, Sarah, Degree granting institution (dgg): Trent University Abstract: <p>Cadmium is a toxic metal that has detrimental effects on blood vessel development and function. To examine the effect of varying concentrations of cadmium on angiogenesis, two in vitro assays were used. First, developing yolk sac blood vessels were studied in gestation day 8 mouse embryos exposed to medium alone, 1.25, or 1.75 μM cadmium chloride (CdCl2). Embryos exposed to 1.25 μM… more
Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Giardia intestinalis is the causative agent of a diarrheal disease in mammals, but the mechanisms of disease pathogenesis are unclear. While proteins secreted by Giardia affect the host cells, the potential of hormone secretion has not been investigated to date. Cytokinins (CKs) are classified as phytohormones, but little is known about their role beyond plants. Mass spectrometry-based… more
Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Population cycles are characterized by predictable temporal oscillations in population size and are influenced by densities of both predators and prey. These oscillations are influenced by the predator functional response, i.e. the influence of prey density on predator kill rate. The Canada lynx (Lynx canadensis) is a predatory mammal with cyclic northern populations driven by snowshoe… more
Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Abstract: <p>We studied the physiological and molecular responses of lab-grown Daphnia pulex to shifts in dietary (carbon, nitrogen, phosphorus, and cyanobacteria) and growth media (calcium) nutrient supply using a set of potential biomarkers via qPCR. Each examined nutrient had a strong effect on Daphnia mass-specific growth rate, and we found significant dose-dependent effects of treatment level (… more
Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Understanding threats to declining species at multiple stages of their annual cycle is important for determining the cause of their declines and conserving their populations. To assess potential responses to changing habitat and predators under climate change, I compared the nest site characteristics, responses to human intruders, and migratory patterns between Short-billed Dowitchers… more
Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Schaffer, Zivi Raiden, Thesis advisor (ths): Power, Ian M, Degree committee member (dgc): Rausis, Kwon, Degree committee member (dgc): Aherne, Julian, Degree committee member (dgc): Dang, Huy, Degree granting institution (dgg): Trent University Abstract: <p>Dissolved inorganic carbon in drainage waters is a direct measurement of carbon dioxide (CO2) removal from enhanced rock weathering (ERW) in soils. In this study, square metre scale field experiments (2021–2023) were conducted in Peterborough Ontario, Canada, each amended with kimberlite residues from Gahcho Kué Diamond Mine (Northwest Territories, Canada) or olivine powder at high… more
Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Abstract: <p>A key knowledge gap in aeolian transport research concerns the adjustment of saltation processes to the extreme conditions found within high-latitude regions. A series of wind tunnel experiments were carried out under full climate control and over a wide range in humidity. Particle entrainment and transport within shearing flows of varied wind speed were monitored over beds of varied… more
Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Dissolved organic matter (DOM) plays a vital role in lake ecosystems, yet its temporal and spatial variations in lakes remain poorly understood. This study investigates DOM dynamics in boreal lakes during the warm season and the Laurentian Great Lakes ice during winter. Sampling 10 boreal lakes in early and late June 2022, revealed subtle changes in DOM in the epilimnion and hypolimnion… more