Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Moose are an iconic species, known for their large size and impressive antlers. Eight subspecies are classified in circumpolar regions of the planet - four in North America. Two subspecies are similar in shape and size, the north-western moose (Alces alces andersoni) and the eastern moose (Alces alces americana). It was previously believed that these two subspecies meet in northern… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Long-term studies of demographic processes such as survival and abundance conducted in unexploited systems provide unique insight into the natural population ecology of fish, but are rarely available. I used historical tagging records of a sanctuary population of brook trout (Salvelinus fontinalis) in Algonquin Park, Ontario to investigate long-term population dynamics in an unexploited… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>This study assesses the bioavailable metal (Cu, Ni, Zn, Pb) species in the Athabasca-Mackenzie watersheds using diffusive gradient in thin films (DGT) devices. Metal toxicity is not only based on the concentration of metal in natural waters, but also on the nature of metal species. Four main forms in aquatic systems are: free ion, inorganic species, DOM bound (humic) species and metal… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The recent northward expansion of the white-footed mouse (Peromyscus leucopus) in response to climatic changes provides a natural experiment to explore potential adaptive genetic variation within the clock gene Per1 in Peromyscus undergoing latitudinal shifts, as well as, the possibility of hybridization and introgression related to novel secondary contact with its sister species the… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Daphnia are keystone consumers in many pelagic ecosystems because of their central role in nutrient cycling. Daphnia are also frequently infected, and the parasites causing these infections may rival their hosts in their ability to regulate ecosystem processes. Therefore, parasitic exploitation of Daphnia may alter nutrient cycling in pelagic systems. This thesis integrates existing… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Improving current understanding of the factors that control soil carbon (C) dynamics in forest ecosystems remains an important topic of research as it plays an integral role in the fertility of forest soils and the global carbon cycle. Invasive earthworms have the potential to alter soil C dynamics, though mechanisms and effects remain poorly understood. To investigate potential effects… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The objective of this thesis was to assess current spatial trends and historic trends in the accumulation of trace metals related to the Athabasca Oil Sands Region (AOSR). The AOSR hosts some of the largest industrial developments in Canada, yet relatively little is known about the transport and fate of trace metal emissions from the region – particularly in the relatively remote areas… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>While previous studies have focused on how road salt affects water quality and vegetation, limited research has characterized road salt distribution through soil and the resulting impacts. The potential for sodium (Na+) to be retained and impact soil physical and chemical properties is likely to vary depending on the soil's parent material, and more specifically on the extent of… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Decomposition of aquatic macrophytes has an important role in defining lake carbon (C) storage and nutrient dynamics. To test how diversity impacts decomposition dynamics and site-quality effects, I first examined whether the decomposition rate of aquatic macrophytes varies with species richness. Generally, I found neutral effects of mixing, with initial stoichiometry of component… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The flavohemoglobin in Giardia intestinalis (gFlHb) is the only known protozoan member of a protein class typically associated with detoxifying nitric oxide (by oxidation to nitrate) in bacteria and yeast. Mutants of the B10 tyrosine (Y30F) and E11 leucine (L58A), conserved residues thought to influence ligand binding, were expressed and studied using Resonance Raman (RR) spectroscopy.… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Environmental variation can affect consumer trait expression and alter ecological and evolutionary dynamics in natural populations. However, although dietary nutrient content can vary by an order of magnitude in natural ecosystems, intra-specific differences in consumer responses to food quality have not been thoroughly investigated. Therefore, the purpose of my dissertation was to… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Arctic terrestrial ecosystems have experienced substantial structural and compositional changes in response to warming climate in recent decades, especially the expansion of shrub species in Arctic tundra. Climatic and vegetation changes could feedback to the global climate by changing the carbon balance of Arctic tundra. The objective of this thesis was to investigate the influence of… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Despite being an essential nutrient at trace levels, selenium can be devastating to aquatic environments when present in excess. There is no apparent correlation between total aqueous selenium concentrations and observed toxic effects because bioaccumulation varies over several orders of magnitude depending on the chemical species of selenium and the biological species present in the… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Micropollutants are discharged into the aquatic environment with industrial and domestic wastewater and these compounds may cause toxic effects in aquatic organisms. In this study, the toxic effects to fish of micropollutants extracted from ozonated and nonozonated municipal wastewater effluent (MWWE) were measured in order to assess the effectiveness of ozonation in reducing toxicity.… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The epoxides of oligomeric self-metathesized soybean oil (MSBO) and cross-metathesized palm oil (PMTAG) and canola oil (CMTAG) containing terminal double bonds were used to produce nonisocyanate polyurethanes (NIPUs) as well as anhydride, amine and thiol-cured epoxies. </p><p>The synthesized NIPUs displayed metal adhesive properties for CMTAG and MSBO with MSBO being favoured… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>A species of concern is caribou (Rangifer tarandus), a species in decline across most of the circumpolar North, including the island of Newfoundland. Resource exploitation across caribou ranges is projected to accelerate in the coming decades as oil extraction, roads, forest harvesting, and mining encroach upon their habitat. Hydroelectric corridors, in particular, are anticipated to… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Giardia intestinalis is a protozoan parasite that causes waterborne diarrheal disease in animals and humans. It is an unusual eukaryote as it lacks the capacity for heme biosynthesis; nonetheless it encodes heme proteins, including three cytochrome b5 isotypes (gCYTB5s) of similar size. Homology modelling of their structures predicts increased heme pocket polarity compared to mammalian… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Interseeding legume cover crops in grain corn may improve the environmental sustainability of corn production system in Southern Ontario. This study aimed to assess the effects of legume species, nitrogen (N) fertilizer rate and arbuscular mycorrhizal fungi (AMF) inoculation on biomass and N requirement in a corn-legume system. Corn was grown with red clover (RCl), microclover (MCl),… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The aim of this work was to identify the DNA sequences recognized by the Giardia TBP (gTBP) in vivo by using a chromatin immunoprecipitation assay (ChIP). Since a specific antibody for the protein of interest is required for this assay, a company was contracted to produce and purify a custom polyclonal antibody from the immunization of rabbits. Recombinant GST-gTBP was produced at a… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Serrao, Natasha Rosemary, Thesis advisor (ths): Wilson, Chris C, Degree committee member (dgc): Dextrase, Alan, Degree committee member (dgc): Freeland, Joanna, Degree committee member (dgc): Reid, Scott, Degree granting institution (dgg): Trent University Abstract: <p>Recent range reductions of endangered species have been linked to urban development, increased agricultural activities, and introduction of non-native species. I used Redside Dace (Clinostomus elongatus) as a focal species to examine the utility of novel monitoring approaches, and to understand historical and contemporary processes that have influenced their present distribution. I… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>This study assesses the ability of a unicellular protist, Euglena gracilis, to remove Cu and Ni from solution in mono- and bi-metallic systems. Living Euglena cells and non-living Euglena biomass were examined for their capacity to sorb metal ions. Adsorption isotherms were used in batch systems to describe the kinetic and equilibrium characteristics of metal removal. In living systems… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Shetranjiwalla, Shegufta, Thesis advisor (ths): NARINE, SURESH S, Thesis advisor (ths): Vreugdenhil, Andrew, Degree committee member (dgc): Metcalfe, Chris, Degree committee member (dgc): Dawson, Peter, Degree granting institution (dgg): Trent University Abstract: <p>Thermoplastic poly(ester urethane)s (TPEU)s derived from vegetable oils possess inferior physical properties compared to their entirely petroleum-based counterparts due to the structural limitations and lower reactivity of the precursor lipid-derived monomers. The present work shows that high molecular weight of TPEUs with enhanced performance can be obtained from lipid-derived monomers… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>This study examines the influence of dissolved organic matter (DOM) on dissolved vanadium (V) speciation in the Churchill River and Great Slave Lake using diffusive gradients in thin film (DGT). Vanadium is commonly found in natural environments such as rivers, lakes and oceans. It regulates normal cell growth, but in excessive amounts, it can have toxic effects on human and aquatic… more Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Based on an endogenous hormone study, three cytokinin type phytohormones; benzyladenine (BA), trans-zeatin (tZ) and methylthiol trans-zeatin (MeSZ), as well as abscisic acid (ABA) were exogenously added at three concentrations (10-7, 10-6 and 10-5 M) to cultures of Chlorella vulgaris in an attempt to alter growth rate, total lipid and fatty acid yields and fatty acid profile. Growth… more 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
