Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Most grassland bird populations are in decline, so it is becoming increasingly important to understand how they use agricultural field types and form their communities. I performed point counts in cultural meadow, intensive agriculture, and non-intensive agriculture areas in 2011 and 2012. Generalized linear models were used to determine the habitat relationships of six focal species. I… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Changes to the Arctic and sub-Arctic climate are becoming increasingly evident as it warms faster than other areas of the globe, supporting evidence that predictions of future warming will be amplified due to positive feedback mechanisms. The Southern Hudson Bay polar bear (<italic>Ursus maritimus</italic>) subpopulation is one of the most southerly subpopulations in the… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Lalor, Jillian L., Thesis advisor (ths): Bowman, Jeff, Thesis advisor (ths): Wilson, Paul J, Degree committee member (dgc): Schulte-Hostedde, Albrecht, Degree committee member (dgc): Murray, Dennis, Degree granting institution (dgg): Trent University Abstract: <p>While hybridization between distinct taxa can have undesirable implications, it can also result in increased genetic variability and potentially, the exchange of adaptive genes or traits. Adaptive variation acquired through introgressive hybridization may be particularly advantageous for species facing rapid environmental change. I investigated a novel, climate change-induced hybrid zone… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p><italic>Magnolia acuminata</italic> (Cucumber tree) is the only native Magnolia in Canada, where it is both federally and provincially listed as endangered.<italic>Magnolia acuminata</italic> in Canada can be found inhabiting pockets of Carolinian forest within Norfolk and Niagara regions of southwestern Ontario. Using a combination of nuclear and chloroplast… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p><bold>Fractionation of mercury isotopes in an aqueous environment: Chemical Oxidation</bold></p><p><italic>Dimitri Stathopoulos</italic></p><p>The study of fractionation patterns for the stable isotopes of mercury is a growing field. The potential for stable isotopes to trace mercury through the environment from pollution sources to sinks… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Webster, Eva Marie, Thesis advisor (ths): Ellis, David A, Degree committee member (dgc): Harner, Tom, Degree committee member (dgc): Hintelmann, Holger, Degree committee member (dgc): Koprivnjak, Jean-François, Degree granting institution (dgg): Trent University Abstract: <p>Ionizing organic chemicals are recognized as constituting a large fraction of the organic chemicals of commerce. Many governments internationally are engaged in the time-consuming and expensive task of chemical risk assessment for the protection of human and environmental health. There are standard models that are consistently used to supplement experimental and monitoring data in such… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The Pearl River Estuary (PRE) and eastern Taiwan Strait (ETS) populations of Indo-Pacific humpback dolphins (Sousa chinensis) contain ~600 and 100 catalogued individuals, respectively. Population demography is important for conservation actions but few animals have been sexed by conventional methods. Longitudinal analysis of tooth-rake scars on dorsal fins showed scars disappear within 7… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Silver nanoparticles (AgNP) released into aquatic environments could threaten natural bacterial communities and ecosystem services they provide. We examined natural lake bacterioplankton communities' responses to different exposures (pulse vs chronic) and types (citrate and PVP) of AgNPs at realistic environmental conditions using a mesocosm study at the Experimental Lakes Area. An… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Benthic macroinvertebrtes (BMI) are functionally important in aquatic ecosystems; as such, knowledge of their community structure and function is critical for understanding these systems. BMI were sampled from ten lakes in each of two regions of south-central Ontario to investigate which chemical and physical variables could be shaping their community structure and function. Ten… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>ABSTRACT</p><p>Calving site selection and fidelity in a restored elk (Cervus elaphus) herd in Bancroft</p><p>Ontario, Canada.</p><p>Michael R. Allan</p><p>Parturition site selection by ungulates is believed to be influenced by forage abundance and concealment from predators. In 2011 and 2012, I used vaginal implant transmitters and… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Effective population size (Ne) is a key concept in population genetics, evolutionary biology and conservation biology that describes an important facet of genetic diversity and the capacity of populations to respond to future evolutionary pressures. The importance of Ne in management and conservation of wild populations encouraged the development of numerous genetic estimators which rely… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>This thesis was designed to quantify absorbance and fluorescence characteristics of dissolved organic matter (DOM) in North Atlantic, Pacific and Arctic Oceans. DOM was described in water masses of distinct sources and formation pathways as well as in regions where environmental forcings such as deep water upwelling, enhanced biological activity and receipt of freshwater discharge were… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Bennett, Amanda Maria, Thesis advisor (ths): Murray, Dennis L, Degree committee member (dgc): Burness, Gary, Degree committee member (dgc): Kerr, Leslie, Degree committee member (dgc): Ridgway, Mark, Degree granting institution (dgg): Trent University Abstract: <p>Inducible defenses are plastic responses by an organism to the perception of predation risk. This dissertation focuses on three experiments designed to test the hypothesis that plastic ability is limited by energetic constraints. Chapter 1 provides a general introduction to phenotypic plasticity research and the theoretical costs and limitations affecting the expression of plastic traits… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Since their successful reintroduction, the eastern wild turkey <italic>(Meleagris gallopavo silvestris)</italic> has expanded its range north. Due to different and potentially more severe limiting factors, management approaches generalized from studies within the historical range may not be appropriate to apply to northern populations. To better understand northern wild… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>In this study, we attempt to enhance current knowledge of ecological responses to riverine alterations from waterpower by using a bottom-up food up approach. A series of extensive and intensive study components were performed across northern Ontario, Canada, where biological (nutrients, dissolved organic matter (DOM) and periphyton) and physical (water level and thermal regimes)… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>I used a GIS raster layer of an area in the Churchill, Manitoba region to investigate the effect of breeding habitat on demography and density of Whimbrel from 2010 through 2013. Program MARK was used to quantify adult and daily nest survival. Apparent annual survival of 0.73 ± 0.06 SE (95% CI = 0.60-0.83) did not significantly differ between sexes or habitats and was lower than expected… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>In this study, I investigate the effects of nitrogen (N) and phosphorus (P) on the nutritional stoichiometry and growth of filamentous green algae of the family Zygnemataceae in situ and ex situ. I found a mean of Carbon (C):N:P ratio of 1308:66:1 for populations growing in the Kawartha Lakes of southern Ontario during the summer of 2012. FGA stoichiometry was variable, with much of the… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Abstract</p><p>Early Responses of Understory Vegetation After One Year of Above Canopy Nitrogen Additions in a Jack Pine Stand in Northern Alberta</p><p>Nicole Melong</p><p>Nitrogen (N) emissions are expected to increase in western Canada due to oil and gas extraction operations. An increase in N exposure could potentially impact the surrounding boreal… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Smith, Matthew, Thesis advisor (ths): Wallschlaeger, Dirk, Degree committee member (dgc): Dillon, Peter, Degree committee member (dgc): Belzile, Nelson, Degree committee member (dgc): Gueguen, Celine, Degree granting institution (dgg): Trent University Abstract: <p>Selenide is cited as a geochemically important selenium (Se) species, but it is unknown whether selenide is a stable aqueous ion in natural waters. The feasibility of using anoxic anion exchange chromatography (AEC) coupled to dynamic reaction cell-inductively coupled plasma-mass spectrometry to separate aqueous selenide was investigated with the goal of quantifying this anion to… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Interactions between hosts and pathogens play a crucial role in their adaptation, evolution and persistence. These interactions have been extensively studied in model organisms, yet it is unclear how well they represent mechanisms of disease response in primary vectors in natural settings. The objective of my thesis was to investigate host-pathogen interactions in natural host… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Ringrose, John Lyons, Thesis advisor (ths): Beresford, David, Thesis advisor (ths): Abraham, Ken, Degree committee member (dgc): Beresford, David, Degree committee member (dgc): Abraham, Ken, Degree committee member (dgc): Nol, Erica, Degree granting institution (dgg): Trent University Abstract: <p>I studied the abundance, distribution and diversity of horse fly and deer fly species (Diptera: Tabanidae) and mosquito species (Diptera: Culicidae) in the boreal forest region of northern Ontario in 2011 and 2012. I collected 19 mosquito species, including one species new for Ontario, Aedes pullatus (Coquillett). I documented 11 northern and one southern range extension. I also… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The distribution of animals is rarely random and is affected by various environmental factors. We examined space-use patterns, habitat selection and stress responses of whip-poor-wills to mining exploration activity.To the best of my knowledge, fine scale patterns such as the habitat composition within known home ranges or territories of eastern whip-poor-wills have not been investigated… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The fate of silver nanoparticles (AgNPs) in surface waters determines the ecological risk of this emerging contaminant. In this research, the fate of AgNPs in lake mesocosms was studied using both a continuous (i.e. drip) and one-time (i.e. plug) dosing regime. AgNPs were persistent in the tested lake environment as there was accumulation in the water column over time in drip mesocosms… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Recent declines in growth and condition of Great Lakes' lake whitefish (Coregonus clupeaformis) have been linked to ecosystem-wide changes stemming from the invasion of dreissenid mussels. To test the influence of invasive mussels on this commercially important coregonid species, we collected archived scale samples from ten Great Lake locations and analyzed long-term changes in… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p><italic>Ustilago maydis</italic> (DC) Corda is the causal agent of 'common smut of corn'. Completion of the <italic>U. maydis</italic> lifecycle is dependent on development inside its host, <italic>Zea mays</italic>. Symptoms of <italic>U. maydis</italic> infection include chlorosis and the formation of tumours on all aerial corn… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Stormwater ponds (SWPs) are a common feature in new urban developments where they are designed to minimize runoff peaks from impervious surfaces and retain particulate matter. As a consequence, SWPs can be efficient at retaining particle-bound nutrients, but may be less efficient at retaining nutrients that are present primarily in the dissolved form, like nitrogen (N). However, the… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Nitrogen is a major constituent of agricultural fertilizers, and nitrogen inputs to stream water via runoff and groundwater lead to a variety of negative environmental impacts. In order to quantify the movement of nitrogen through aquatic food webs, fourteen streams with varying land uses across South-Central Ontario were sampled for two species of fish, freshwater mussels, and water for… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Selenium is an essential trace nutrient to many organisms, yet in high concentrations it is toxic. Organic selenium is more bioavailable to aquatic biota than inorganic selenium, but is usually found in much lower concentrations. Algae are known to biotransform inorganic selenium into several organo-selenium compounds, but it is unknown whether any of these bioaccumulate in the food… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The damage to Sudbury's landscape from over a century of smelter and logging activity has been severe and impacts well documented. However, despite their abundance in the region, wetlands have received little attention. Recent studies have identified that nutrient limitation is as much a problem as metal toxicity and highlighted not only the importance of wetlands but also the need… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): McInnes, Mark Andrew, Thesis advisor (ths): Ellis, David A, Degree committee member (dgc): Thompson, Matthew, Degree committee member (dgc): Gueguen, Celine, Degree committee member (dgc): Stock, Naomi, Degree granting institution (dgg): Trent University Abstract: <p>Perfluorinated carboxylic acids (PFCAs) are anthropogenic environmentally ubiquitous surfactants that tend to concentrate on water surfaces. This investigation looked at the effect of simulated rain on the atmospheric concentration of a suite of PFCAs (C2 - C12) above the bulk water system. Increased air concentrations of all PFCAs were detected during simulated rain events. Long chain… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Lin, Shang-Yao Peter, Thesis advisor (ths): Dorken, Marcel E, Thesis advisor (ths): Nol, Erica, Degree committee member (dgc): Crins, William J, Degree committee member (dgc): Freeland, Joanna R, Degree granting institution (dgg): Trent University Abstract: <p>Sexual reproduction in flowering plants depends on investment in reproduction, the mode of pollen transfer, the availabilities of nutrient resources and potential mates, and the spatial scales over which these processes take place. In this thesis, I studied the general reproductive biology of Shepherdia canadensis (L.) Nutt. (Elaeagnaceae) and the suite of pollinators that visit the… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>I investigated the impact of beef-cattle farm management on the reproductive success of Bobolink (<italic>Dolichonyx oryzivorus</italic>) and Eastern Meadowlark (<italic>Sturnella magna</italic>) within Eastern Ontario. I monitored rotational grazing management regimes and hay cut dates while assessing breeding phenology and reproductive success of Bobolinks and… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Johnson, James Anthony, Thesis advisor (ths): Aherne, Julian, Degree committee member (dgc): Watmough, Shaun A, Degree committee member (dgc): Huber, Christian, Degree committee member (dgc): Cummins, Thomas, Degree granting institution (dgg): Trent University Abstract: <p>The objective of this thesis was to assess the influence of anthropogenic sulphur (S) and nitrogen (N) deposition, and harvesting on soil acidity and calcium (Ca<super>2+</super>), magnesium (Mg<super>2+</super>), potassium (K<super>+</super>) and N soil pools in plantation forest soils in Ireland. The response to reductions in anthropogenic S… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Majchrzak, Yasmine Nicole, Thesis advisor (ths): Burness, Gary, Degree committee member (dgc): Mastromonaco, Gabriela, Degree committee member (dgc): Murray, Dennis, Degree committee member (dgc): Bowman, Jeff, Degree granting institution (dgg): Trent University Abstract: <p>Many facilities attempt to alleviate the risk of chronic stress in captivity by providing environmental enrichment shown to minimize behavioural disorders and stress in several species. One potential form of enrichment used in zoos is training animals to perform rides for guests, however, the effect of this activity on the welfare of individual animals has never been examined. I… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The structure and composition of the landscape can facilitate or impede gene flow, which can have important consequences because genetically isolated groups of individuals may be prone to inbreeding depression and possible extinction. My dissertation examines how landscape structure influences spatial patterns of genetic differentiation and diversity of American marten (<italic>… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>This study presents a detailed assessment of the chemical speciation of aluminum and zinc in three streams of a small, acid-sensitive forested catchment on the southern edge of the Precambrian Shield.</p><p>Speciation analysis was achieved using an in-situ analytical technique known as Diffusive Gradient in Thin film (DGT) which measures labile metals, and a predictive… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Glycine max (soybean) is an economically important plant species that registers a relatively low yield/seed weight compared to other food and oil seed crops due to higher rates of flower and pod abortion. Alleviation of this abortion rate can be achieved by altering the sink strength of the reproductive organs of soybeans. Cytokinin (CK) plays a fundamental role in promoting growth of… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Kelly, Nick, Thesis advisor (ths): Burness, Gary, Thesis advisor (ths): Wilson, Chris C, Degree committee member (dgc): Ridgway, Mark S., Degree committee member (dgc): McDermid, Jenni L., Degree granting institution (dgg): Trent University Abstract: <p>In the face of climate change, the persistence of cold-adapted species and populations will depend on their capacity for evolutionary adaptation of physiological traits. As a cold-adapted Ice Age relict species, lake trout (Salvelinus namaycush) are ideal for studying potential effects of climate change on coldwater fishes. I studied the thermal acclimation capacity and aerobic… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Hornseth, Megan L., Thesis advisor (ths): Murray, Dennis L., Degree committee member (dgc): Bowman, Jeff, Degree committee member (dgc): Fortin, Marie-Josee, Degree committee member (dgc): Ray, Justina, Degree granting institution (dgg): Trent University Abstract: <p>Current major issues in conservation biology include habitat loss, fragmentation and population over-exploitation. Animals can respond to landscape change through behavioural flexibility, allowing individuals to persist in disturbed landscapes. Individual behaviour has only recently been explicitly included in population models. Carnivores may be sensitive to changing landscapes due to… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Caribou experience direct and indirect negative effects of harassment from biting flies, influencing behavior and activity on several spatial and temporal scales. I used systematic insect collection surveys during the summers of 2011 and 2012 to examine the spatial and temporal distributions of black flies (Simuliidae), mosquitoes (Culicidae), and deer flies and horse flies (Tabanidae)… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Catchment soil acidification has been suggested as a possible mechanism for reducing phosphorus (P) loading to surface waters in North America and northern Europe, but much of the research that has been conducted regarding P immobilization in pH manipulated soils has been performed at high P concentrations (> 130 μM). This study investigated how soil acidity was related to P… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Balch, Jordan, Thesis advisor (ths): Gueguen, Celine, Degree committee member (dgc): Hickey, Brendan, Degree committee member (dgc): Thompson, Matthew, Degree committee member (dgc): Aherne, Julian, Degree granting institution (dgg): Trent University Abstract: <p>The efficacy of the diffusive gradients in thin films (DGT) passive samplers to provide accurate measurements of free metal ions and those complexed with dissolved organic matter (DOM) was investigated. DOM controls the diffusive properties of DOM-complexed metal species in natural systems. Knowing the diffusion coeiffiecent (D) for DOM of different molecular weights (MW) and the major… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Barrett, Sophie Elizabeth, Thesis advisor (ths): Watmough, Shaun, Degree committee member (dgc): Sager, Eric, Degree committee member (dgc): Emery, Neil, Degree committee member (dgc): Hutchinson, Tom, Degree granting institution (dgg): Trent University Abstract: <p>Peatlands are prevalent in the Sudbury, Ontario region. Compared with the well documented devastation to the terrestrial and aquatic ecosystems in this region, relatively little work has been conducted on the peatlands. The objective of this research was to assess factors controlling peat and plant chemistry, and vegetation composition in 18 peatlands in Sudbury after over 30 years of… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Ahee, Jordan, Thesis advisor (ths): Dorken, Marcel E, Degree committee member (dgc): Freeland, Joanna R, Degree committee member (dgc): Burness, Gary, Degree committee member (dgc): Pond, Bruce, Degree granting institution (dgg): Trent University Abstract: <p>Natural populations of flowering plants rarely have perfectly uniform distributions, so trends in pollen dispersal should affect the size of the pollination neighbourhood and influence mating opportunities. Here I used spatial analysis to determine the size of the pollination neighbourhood in a stand of the herbaceous, wind-pollinated plant (<italic>Typha latifolia</italic>;… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The Pumpkinseed (Lepomis gibbosus) is a sunfish that is endemic to eastern portions of Canada and the United States. During the late 19th century, the species was introduced into Europe, and it is now present in over 28 countries. Previous attempts to determine the characteristics that can predict the spread of non-indigenous species have been largely unsuccessful, but new evidence… more