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
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Agricultural land application of biosolids recycles nutrients and organic matter to the soil, however the effect of treatment process on nutrient availability requires further research for better nutrient management. This study examined the bioavailability of nitrogen (N) and phosphorus (P) in alkaline treated biosolids (TB) when amended into three different soils. Despite a 45%… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Trinucleotide repeats (TNRs) are a class of highly polymorphic microsatellites which occur in neutral and non-neutral loci and may provide utility for individual- and population-identification. Exonic trinucleotide motifs, in particular, offer additional advantages for non-human species that typically utilize dinucleotide microsatellite loci. Specifically, the reduction of technical… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Road mortality is one of the leading causes of global population declines in reptiles and amphibians. Stemming losses from reptile and amphibian road mortality is a conservation priority and mitigation is a key recovery measure. I developed a model of road mortalities relative to non-‐mortalities, based on predictors varying across space (road surface type, traffic volume, speed limit,… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>In this thesis, a methodological framework for the assessment and monitoring of forest degradation based on remote sensing techniques and field data, as part of the REDD+ programme, is presented. The framework intends to support the implementation of a national Monitoring, Verification and Report (MRV) system in developing countries. The framework proposed an operational definition of… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Soil mineralizable nitrogen (N) is the main component of soil N supply in humid temperate regions and should be considered in N fertilizer recommendations. The objectives of this study were to determine the potentially mineralizable N parameters, and improve N fertilizer recommendations by evaluating a suite of soil N tests in southwestern Ontario. The study was conducted over the 2013… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>(MRC) in central Ontario was carried out to determine the range and spatial distribution of soil Ca weathering rates, and investigate the relationships between lake Ca and soil and catchment attributes. The MRC is acid-sensitive, and has a long history of impacts from industrial emission sources in Ontario and the United States. Small headwater catchments were sampled for soil and… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>In this study, the influence of N deposition on the vegetation community of semi-natural oak woodlands in Ireland was assessed through national and regional scale analysis of forest plot data. At both scales, Canonical Correspondence Analysis suggested that N deposition was a predictor of community composition, although site-specific soil characteristics were the strongest predictors of… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Celsie, Alena Kathryn Davidson, Thesis advisor (ths): Mackay, Donald, Thesis advisor (ths): Parnis, Mark, Degree committee member (dgc): Hickie, Brendan, Degree committee member (dgc): Mackay, Donald, Degree committee member (dgc): Parnis, Mark, Degree committee member (dgc): Aherne, Julian, Degree granting institution (dgg): Trent University Abstract: <p>Models of partitioning, uptake, and toxicity of neutral organic chemicals in fish</p><p>Alena Kathryn Davidson Celsie</p><p>A novel dynamic fugacity model is developed that simulates the uptake of chemicals in fish by respiration as applies in aquatic toxicity tests. A physiologically based toxicokinetic model was developed which calculates the time-course of… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>This study investigated the role of the JNK signaling pathway in cadmium-treated mouse embryo forelimb bud cells in vitro. Primary cultures of forelimb bud cells harvested at day 11 of gestation were pre-treated with JNK inhibitor SP600125, and incubated with or without CdCl2 for 15, 30, 60, 120 minutes and 24, 48 hours or 5 days. Endpoints of toxicity were measured through cell… more