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
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The purpose of this study was to quantify the variation of baseline carbon and nitrogen stable isotope signatures in the Lake Simcoe watershed and relate that variation to various physicochemical parameters. Particulate organic matter samples from 2009 and 2011 were used as representatives of baseline isotopic values. Temporal data from two offshore lake stations revealed that δ… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The objective of this thesis is to better understand the demography and habitat selection of Newfoundland caribou. Chapter 1 provides a general introduction of elements of population ecology and behavioural ecology discussed in the thesis. In Chapter 2, I examine the causes of long-term fluctuations among caribou herds. My findings indicate that winter severity and density-dependent… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Baya, Pascale Anabelle, Thesis advisor (ths): Hintelmann, Holger, Degree committee member (dgc): Lamborg, Carl, Degree committee member (dgc): Hickie, Brendan, Degree committee member (dgc): Georg, Bastian, Degree granting institution (dgg): Trent University Abstract: <p>Monomethylmercury (MMHg), the most bioavailable form of mercury (Hg) and a potent neurotoxin, is present at elevated concentrations in Arctic marine mammals posing serious health threats to the local populations relying on marine food for their subsistence living. The sources of MMHg in the Arctic Ocean surface water and the role of dimethylmercury (DMHg) as a source of MMHg remain… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Population density regulation is a fundamental principle in ecology, however there remain several unknowns regarding the functional expression of density dependence. One prominent view is that the patterns by which density dependence is expressed are largely fixed across a species, irrespective of environmental conditions. Our study investigated the expression of density dependence in… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Extensive research has gone into measuring changes to the carbon storage capacity of Arctic terrestrial environments as well as large water bodies in order to determine a carbon budget for many regions across the Arctic. Inland Arctic waters such as small lakes and ponds are often excluded from these carbon budgets, however a handful of studies have demonstrated that they can often be… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Browning, Mark Henry, Thesis advisor (ths): Davies, Chris, Thesis advisor (ths): Buttle, Jim, Degree committee member (dgc): Lafleur, Peter, Degree committee member (dgc): Whillans, Tom, Degree granting institution (dgg): Trent University Abstract: <p>Theoretical work on community recovery, development, stability, and resistance to species invasions has outpaced experimental field research. There is also a need for better integration between ecological theory and the practice of ecological restoration. This thesis investigates the dynamics of community assembly following peat mining and subsequent restoration efforts at Canada's… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Climate change has had numerous impacts on species' distributions by shifting suitable habitat to higher latitudes and elevations. These shifts pose new challenges to biodiversity management, in particular translocations, where suitable habitat is considered crucial for the reintroduced population. De-extinction is a new conservation tool, similar to reintroduction, except that the… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Sherritt, Ayden Frazer, Thesis advisor (ths): Schaefer, James A, Thesis advisor (ths): Pond, Bruce A, Degree committee member (dgc): Brown, Glen S, Degree committee member (dgc): Brannen, Dennis, Degree granting institution (dgg): Trent University Abstract: <p>Site fidelity is the behaviour of individuals to return to the same location; for female woodland caribou it may reflect reproductive success and depend on habitat quality. I investigated the influence of landscape and disturbance conditions on fidelity among three populations in Manitoba and Ontario, Canada. Habitat classifications were based on Forest Resource Inventory (FRI) and… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Pacific Rim National Park Reserve's 16 km of coastal beaches attract many thousands of people and shorebirds every year. To identify locations where shorebirds concentrate and determine the impact of human activity and habitat characteristics on shorebirds, I conducted shorebird and visitor surveys at 20 beach sectors during fall migration in 2011 to 2013 and spring migration in… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Zigouris, Joanna, Thesis advisor (ths): Schaefer, James A, Thesis advisor (ths): Kyle, Christopher J, Degree committee member (dgc): Wilson, Paul J, Degree committee member (dgc): Bowman, Jeff, Degree granting institution (dgg): Trent University Abstract: <p>Habitat loss and fragmentation can disrupt population connectivity, resulting in small, isolated populations and low genetic variability. Understanding connectivity patterns in space and time is critical in conservation and management planning, especially for wide-ranging species in northern latitudes where habitats are becoming increasingly fragmented. Wolverines (Gulo gulo) share… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Livestock predation by wild predators is a frequent and complicated issue, often cited as a significant factor in the decline of livestock production and justification for killing predators. Coyotes (Canis latrans) are the primary predators of sheep in Ontario. Some farms appear to be more susceptible to predation than others, despite the use of mitigation techniques. I explored land… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>My objective was to understand how individual variation, in conjunction with variation in habitat, can affect individual and population-level variation in animal space use. I used coyotes (Canis latrans) as a model species to investigate the roles of hybridization, an inherited intrinsic factor, and spatial memory, a learned intrinsic factor, on space use. I used a diversity of methods… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The endangered North Atlantic right whale (Eubalaena glacialis) has been internationally protected from whaling since 1935 but recovery has been slow compared to the southern right whale (Eubalaena australis) due to anthropogenic mortalities and poor reproduction. Prey availability, genetic variability, and alleles of genes associated with reproductive dysfunction have been hypothesized… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Iridoviruses are large (120-200nm) double stranded DNA viruses that contain an icosahedral capsid. The iridoviridae family is composed of five genera that infect a wide range of poikilothermic vertebrates (Lymphocystivirus, Ranavirus and Megalocyivirus) and invertebrate hosts (Iridovirus, Chloriridovirus). Frog virus 3 (FV3) is a member of the Ranavirus genus, and is commonly used as a… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Maintaining functional connectivity among wildlife populations is important to ensure genetic diversity and evolutionary potential of declining populations, particularly when managing species at risk. The Boreal Designatable Unit (DU) of woodland caribou (Rangifer tarandus caribou) in Ontario, Manitoba, and Saskatchewan has declined in southern portions of the range because of increased… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The reliability and performance of four passive sampler membrane coatings specific to nitrogen dioxide (NO2) were evaluated through co-exposure at multiple Ontario Ministry of Environment and Climate Change (OMOECC) active monitoring stations. All four coatings performed relatively similar under a wide range of meteorological conditions, notably showing exposure-specific atmospheric… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>I determined the direct influence of single-tree selection harvesting on the daily nest survival rates and nest success of 5 focal bird species within a monotypic red pine (Pinus resinosa) plantation on the western edge of the Oak Ridges Moraine in southern Ontario, Canada. I located and monitored 290 nests during the 2012 and 2013 breeding season. I used the logistic-exposure method to… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Identifying the population origin of aquaculture-reared caviar is crucial for both conservation and management strategies of farmed fish but could also facilitate international trade of a CITES regulated product. Shortnose sturgeon (Acipenser brevirostrum) is the main source of caviar production in Atlantic Canada, from Breviro Caviar Inc. aquaculture facility. Shortnose sturgeon are… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The increasing production and use of silver nanoparticles (AgNPs) raise concerns on environmental exposure and impact. A large scale in situ enclosure study was conducted at the Experimental Lakes Area to determine the effect of AgNPs on natural phytoplankton and zooplankton communities. This study investigated AgNPs of varying concentrations (4, 16 and 64 μg/L), dosing regimens… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The breeding phenology of American Woodcocks (Scolopax minor) was evaluated in Ontario, Canada to determine if changes in dates of courtship activity have introduced negative bias into the American Woodcock Singing-ground Survey (SGS). Long-term woodcock phenology and climate data for Ontario were analysed using linear regression to determine if woodcock breeding phenology has changed… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Phylogeographic histories of taxa around the Great Lakes region in North America are relevant to a range of ongoing issues including conservation management and biological invasions. In this thesis I investigated the comparative phylogeographic histories of plant species with disjunct distributions and plant species with continuous distributions around the Great Lakes region; this is a… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Giardia lamblia is an intestinal parasite found globally in freshwater systems that is responsible for endemic outbreaks of infectious diarrhea. As a unicellular parasite that lacks mitochondria, a respiratory chain and lives in the anaerobic environment of its host's intestine, Giardia was assumed for decades to lack heme proteins. However, its genome encodes several putative heme… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Groundwater recharge was estimated and compared in two open grasslands, three mixed deciduous forest stands (100+ years in age), three young red pine plantations (27 ¨C 29 years in age) and two old red pine plantations (62 ¨C 63 years in age) on the Oak Ridges Moraine, southern Ontario, Canada. Recharge was estimated using a 1-d water balance with measured precipitation, throughfall,… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Around the world, many populations of migratory shorebirds appear to be declining. Conservation strategies to reverse declining trends rely on, among other information, a firm understanding of breeding ground population dynamics. From 2010 to 2014, I studied a breeding population of Dunlin (Calidris alpina hudsonia) near Churchill, Manitoba using mark-recapture methods. I found that… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Decreasing lake calcium (Ca) concentration, in lakes located in base poor</p><p>catchments of the Muskoka River Watershed (MRW) in south-central Ontario, is a well- established acid-rain driven legacy effect threatening the health and integrity of aquatic ecosystems that can be compounded by additional Ca removals through forest harvesting. The objectives of this thesis were… more