Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Socio-ecological systems are inherently complex and marine mammals are fundamentally challenging to study. In the Arctic, marine mammals occupy a central ecological role, as nutrient cyclers and as a source of food and culture for Indigenous peoples. Inuit have developed a rich knowledge system, which has not been fully actualized in application in most Arctic research. Considering the… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Metal binding to dissolved organic matter (DOM) determines metal speciation and strongly influences potential toxicity. The understanding of this process, however, is challenged by DOM source variation, which is not always considered by most existing metal speciation models. Source determines the molecular structure of DOM, including metal binding functional groups. This study has… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The amitochondrial protozoan, Giardia intestinalis, encodes four members of the cytochrome b5 (CYTB5) family of heme proteins of unknown function. While homology models can predict the likely fold of these proteins, supporting experimental evidence is lacking. The small size of the cytochromes (~16 kDa) makes them attractive targets for structural analysis by Electron Paramagnetic… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The parasitic protist Giardia intestinalis lacks most heme proteins yet encodes a flavohemoglobin (gFlHb) that converts nitric oxide to nitrate and likely protects the cell from nitrosative stress. In this work an antibody raised against gFlHb was used to examine both changes in gFlHb expression levels and intracellular localization in Giardia in response to nitrosative stress. Giardia… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>This study focused on detecting 22 target anti-estrogenic and anti-androgenic compounds in surface waters influenced by both discharges of municipal wastewater and agricultural runoff in Canada and Argentina. Polar organic chemical integrative samplers (POCIS) were used to monitor the target compounds in surface waters. The removals of the target compounds in a municipal wastewater… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Chemical cues are used commonly by prey to identify predation risk in aquatic environments. Previous work has indicated that negatively-charged ions of m/z 501 are possibly a kairomone that induces anti-predator responses in tadpoles. This thesis found that this ion species: (i) is produced by injured tadpoles; (ii) exhibits increased spectral intensity with higher tadpole biomass; and (… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Timber harvest can influence the rate of transfer of organic matter from the terrestrial catchment to streams, which may have both direct and indirect effects on in-stream nutrient pools and dynamics. In the interest of developing sustainable forestry practices, the continued study of the effects of forestry on nutrient dynamics in aquatic systems is paramount, particularly in sensitive… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Ogungbemide, Damilare Immanuel, Thesis advisor (ths): McKenna Neuman, Cheryl, Degree committee member (dgc): Lafleur, Peter, Degree committee member (dgc): Buttle, Jim, Degree committee member (dgc): Hill, Stephen, Degree granting institution (dgg): Trent University Abstract: <p>A set of experiments was designed to investigate the factors—atmospheric and surficial—controlling fugitive dust emissions from the tailings ponds of UNIMIN Canada, a mining company that extracts and produces nepheline syenite (feldspar) at two adjacent sites (Nephton and Blue Mountain) located north of Havelock, Ontario. Using wind tunnel measurements, the combined influence of relative… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Currier, Charise A., Thesis advisor (ths): Freeland, Joanna, Thesis advisor (ths): Wilson, Chris C, Degree committee member (dgc): Morris, Todd J, Degree committee member (dgc): Schaefer, James A, Degree granting institution (dgg): Trent University Abstract: <p>Environmental DNA (eDNA) detection uses species-specific markers to screen DNA from bulk samples, such as water, to infer species presence. This study involved the development and testing of species-specific markers for four freshwater pearly mussels (Unionidae). The markers were applied to water samples from intensively sampled mussel monitoring sites to compare species detections from… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>In this thesis, water mass distribution of dissolved organic matter (DOM) characteristics (i.e. molecular weight, fluorescent components, thiols and humic substances concentration) was observed in the Arctic Ocean. For the first time, DOM molecular weight (MW) in Beaufort Sea was assessed using asymmetrical flow field-flow fractionation, as well as the first monitoring of thiols and… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Puccinia triticina, wheat leaf rust (WLR), is the most economically damaging fungal rust of wheat on a global scale. This study identified transcriptome changes in a recently emerged race of WLR in Ontario with a new virulence type relative to a possible ancestor race. Also, this study focused on detecting variation in candidate virulence genes and uncovering novel insight into WLR… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>To study the Giardia intestinalis cell cycle, counterflow centrifugal elutriation (CCE) was used to separate an asynchronous trophozoite culture into fractions enriched for cells at the different stages of the cell cycle. For my first objective, I characterized the appearance of a third peak (Peak iii) in our flow cytometry analysis of the CCE fractions that initially suggested the… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>In 2008, the first North American water soldier (Stratiotes aloides) population was discovered in the Trent River, Ontario. Water soldier is an invasive aquatic plant with sharp, serrated leaves that has the potential to spread rapidly through dispersed vegetative fragments. Although it is too late to prevent water soldier establishment in the Trent River, its local distribution remains… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The release of domestic organisms to the wild is considered a threat to </p><p>biodiversity because the introduction of domestic genes through interbreeding can </p><p>negatively impact wild conspecifics via outbreeding and local extinction. In North </p><p>America, captive American mink (Neovison vison) are frequently escaping into the wild, </p… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Poole, Sarah Kathleen, Thesis advisor (ths): Obbard, Martyn E., Thesis advisor (ths): Schaefer, James A., Degree committee member (dgc): Nocera, Joseph J., Degree committee member (dgc): Ray, Justina C., Degree granting institution (dgg): Trent University Abstract: <p>I investigated site fidelity and habitat selection of American black bears (Ursus americanus) from 15 GPS-collared adult females in central Ontario, Canada over nine years. I used generalized linear mixed models to determine the factors affecting between-year variation in fall fidelity and the habitat selection in movement paths. I assessed second and third-order habitat preference by… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Stressors are often an inescapable part of an organism's life. While the effects of many stressors have been well studied individually, potential interactions between stressors exist that may result in greater than additive negative effects. Stressors may be linked by conflicting demands on energy budgets, interfering with important physiological pathways, or necessitating… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Tree harvesting alters nutrient cycling and removes nutrients held in biomass, and as a result nutrient availability may be reduced, particularly in naturally oligotrophic ecosystems. Selection harvesting is a silvicultural technique limited to tolerant hardwood forests where individual or small groups of trees are removed creating a "gap" in the forest canopy. In order for… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>As an emerging contaminant, the antimicrobial agent silver nanoparticles (AgNPs) have been receiving considerable attention to determine their potential effects to aquatic ecosystems. However, estimates of aquatic consumer survivorship and other toxicological endpoints vary considerably among experiments, largely due to the environment in which the test takes place. Throughout this… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The Oak Ridges Moraine (ORM) is a key hydrogeologic feature in southern Ontario. Previous work has emphasized the importance of depression-focused recharge (DFR) for the timing and location of groundwater recharge to the ORM's aquifers. However, the significance of DFR has not been empirically demonstrated and the relative control of land cover, topography, and surficial geology on… more Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Invasive aquatic plants can create negative ecological, economic and social impacts when they displace local vegetation, interfere with shipping and navigation and inhibit water-based recreational activities. In 2008, the first North American occurrence of the invasive plant Stratiotes aloides (Water soldier) was identified in the Trent River, Ontario. This research measured offset… more
