Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The cyanidation technique is currently a viable technique for gold recovery that can replace the present amalgamation technique in Guyana. To implement this technique effectively, laboratory scale experiments and at scale runs were conducted to determine the best particle size of the ore, cyanide concentration, and leaching time. In addition, the profitability of cyanidation was compared… more
Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Northern and southern flying squirrels (Glaucomys sabrinus and G. volans, respectively) are experiencing a climate change induced increase in range overlap, resulting in recent hybridization. We investigated the occurrence of heterospecific communal nesting, a potential facilitator of hybridization, and aimed to confirm the presence of torpor, a potential barrier to hybridization, in… more
Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Phosphorus (P) is an essential macronutrient. In south-central Ontario, foliar P concentrations are low and studies have suggested that P may be limiting forest productivity. Current catchment mass balance estimates however, indicate that P is being retained suggesting that P should not be limiting to tree growth. Phosphorus deposition is measured using bulk deposition collectors, which… more
Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>This thesis explored the contribution of mixed methods approaches to marine mammal science through the use of concurrent and sequential designs to study distribution and feeding ecology of bowhead whales (Balaena mysticetus) in the Arctic region of Nunavik, Quebec, Canada. The study combines Inuit knowledge (IK), collected through semi-directed interviews with Inuit harvesters, and… more
Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Otis, Josée-Anne, Thesis advisor (ths): Murray, Dennis, Degree committee member (dgc): Thornton, Daniel, Degree committee member (dgc): Bowman, Jeff, Degree committee member (dgc): Conolly, James, Degree granting institution (dgg): Trent University Abstract: <p>Currently there are large areas of the North American landscape that are occupied by Canis spp. hybrids of several varieties, leading to the logical question as to the genetic structure and ecological function of Canis populations across the continent, and to what extent hybrids reflect contemporary landscapes. This study illustrated patterns of niche differentiation between parental… more
Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Cytokinin biosynthesis in organisms aside from plant species has often been viewed as a byproduct of tRNA degradation. Recent evidence suggests that these tRNA degradation products may actually have a role in the development of these organisms, particularly fungi. This thesis examines the importance of cytokinins, a group of phytohormones involved in plant cell division and… more
Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Fishers (Pekania pennanti) were extirpated from many parts of Ontario in the early 20th century, but as of the early 2000s the species had recolonized most of its historical range. While the primary population genetic structure of fishers in central and eastern Ontario has not changed drastically over the past ten years, we did find evidence of increased secondary structure and a… more
Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The activities of phytohormones during the reproductive phase have been partially clarified in seed physiology while the biological role of plant hormones in oil accumulation during seed development has been investigated in part only. In this research, fatty acid (FA) contents and hormone profiles, including abscisic acid (ABA) and cytokinins (CKs) of seed samples in four different… more
Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>There are three cattail (Typha) taxa in Canada: T. latifolia (native), T. angustifolia (introduced), and their hybrid T. x glauca. The latter is invasive in regions around the Laurentian Great Lakes, and I investigated the potential role that commercial suppliers may be playing in the introduction of non-native Typha by comparing genotypes of North American, European, and commercially… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Total phosphorus (TP) concentrations have declined in many lakes and streams across south- central Ontario, Canada over the past three decades and changes have been most pronounced in wetland-dominated catchments. In this study, long-term (1980-2007) patterns in TP concentrations in streams were assessed at four wetland-dominated catchments that drain into Dickie Lake (DE) in south-… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Migratory and sedentary ecotypes are phenotypic distinctions of woodland caribou. I explored whether I could distinguish between these ecotypes in Manitoba and Ontario using genetic signatures of adaptive differentiation. I anticipated that signatures of selection would indicate genetic structure and permit ecotype assignment of individuals. Cytochrome-b, a functional portion of the… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The emission of acid precursors by large point sources in Western Canada</p><p>(such as the Athabasca Oil Sands Region) has prompted studies into the possible impact to downwind aquatic and terrestrial ecosystems. Sensitivity of catchments to acidic deposition was estimated for the total lake population of northern Saskatchewan (n=89,947) using regression kriging. Under the… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Most delphinids produce narrowband frequency-modulated whistles with a high level of plasticity to communicate with conspecifics. It is important to understand geographic variation in whistles as signal variation in other taxa has provided insight into the dispersal capabilities, genetic divergence and isolation among groups, and adaptation to ecological conditions. I investigated… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Sex-specific genetic structure is a commonly observed pattern among vertebrate species. Facing differential selective pressures, individuals may adopt sex-specific life historical traits that ultimately shape genetic variation among populations. Although differential dispersal dynamics are commonly detected in the literature, few studies have investigated the potential effect of sex-… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Cuss, Chad Warren, Thesis advisor (ths): Gueguen, Celine, Degree committee member (dgc): Watmough, Shaun, Degree committee member (dgc): McConnell, Sabine, Degree committee member (dgc): Dillon, Peter, Degree granting institution (dgg): Trent University Abstract: <p>Dissolved organic matter (DOM) is a mixture of molecules with dynamic structure and composition that are ubiquitous in aquatic systems. DOM has several important functions in both natural and engineered systems, such as supporting microorganisms, governing the toxicity of metals and other pollutants, and controlling the fate of dissolved carbon. The structure and composition of DOM… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Urban and agricultural activities may introduce chemical stressors, including contaminants of emerging concern (CECs) and current use pesticides (CUPs) into riverine systems. The objective of this study was to determine if fish collected from sites in a river show biomarkers of exposure to these classes of contaminants, and if the biomarker patterns vary in fish collected from urbanized… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Aquatic consumers frequently face nutritional limitation, caused in part, by imbalances between the nutrients supplied by primary producers and the metabolic demands of the consumers. These nutritional imbalances alter many ecological processes including consumer life-history traits, population dynamics, and food web properties. Given the important ecological role of organismal nutrition… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>As part of a mandate to control the spread of Stratiotes aloides (WS; water soldier) in the Trent Severn Waterway, the Ministry of Natural Resources (MNR) created a management plan to eradicate WS. However, one of the biggest challenges in eradicating WS or any invasive aquatic plant is the ability to estimate the extent of its spread and detect new populations. While current detection… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Klein, Michelle Nicole, Thesis advisor (ths): White, Brad N., Thesis advisor (ths): Wang, John Y., Degree committee member (dgc): Nocera, Joseph J., Degree committee member (dgc): Kerr, Leslie R., Degree granting institution (dgg): Trent University Abstract: <p>Marine mammals with near-shore distributions are susceptible to human-related recreational and commercial disturbances, particularly near densely populated and industrialized coastal areas. A population of over 2,500 Chinese humpback dolphins (Sousa chinensis chinensis) occupies the Pearl River Estuary in southern China. A part of this population uses Hong Kong's waters off of… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Ustilago maydis is a basidiomycete smut fungus and the causal agent of common smut of corn. Disease progression and fungal development in this pathogen occur in planta, terminating in the production of dormant teliospores. Dormant spores of many fungi are characterized by reduced metabolic activity, which is restored during spore germination. The transition out of dormancy requires the… more