Year: 2023, 2023
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Brown, Rachel, Thesis advisor (ths): Aherne, Julian, Degree committee member (dgc): Koprivnjak, Jean-François, Degree committee member (dgc): Sager, Eric, Degree committee member (dgc): Lafleur, Peter, Degree granting institution (dgg): Trent University Abstract: <p>In this study, twenty lake catchments surrounding Iqaluit, Baffin Island, were assessed for trace element concentrations (Al, As, Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Sb, Se, THg, V, Zn) in lake water, catchment soil, lake sediment, and moss (Hylocomium splendens). Additionally, the sources of each trace element were determined through the positive matrix factorization (PMF) model and… more
Year: 2023, 2023
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Karl, Katrina Anna-Marie, Thesis advisor (ths): Aherne, Julian, Degree committee member (dgc): Sager, Eric, Degree committee member (dgc): Liang, Tanner, Degree committee member (dgc): Hickie, Brendan, Degree committee member (dgc): McKenna-Neuman, Cheryl, Degree granting institution (dgg): Trent University Abstract: <p>Plastic pollution is a growing concern, owing to its durability, ubiquity, and potential health impacts. The overall objective of this study was to assess the abundance and distribution of microplastics within Lake Scugog catchment, Ontario. This was fulfilled through two tasks (i) the development of a microplastic particle budget for the lake catchment, and (ii) the determination of the… more
Year: 2023, 2023
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Ecological restoration of grassland ecosystems is increasing in scope in Ontario, as a result the demand for genetically appropriate, high-quality seeds of native plants is also
increasing. This mixed methods study characterized fitness and seed quality traits using
genetic, demographic and growth trial data for a keystone tallgrass prairie species Big
bluestem (Andropogon gerardii).… more
Year: 2023, 2023
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Levasseur, Patrick, Thesis advisor (ths): Watmough, Shaun, Degree committee member (dgc): Aherne, Julian, Degree committee member (dgc): Sager, Eric, Degree committee member (dgc): Emilson, Erik, Degree granting institution (dgg): Trent University Abstract: <p>Mining and smelting degraded landscapes are characterised by heavily eroded soils that are acidic, contaminated with toxic metals, and depleted of essential nutrients. Regreening degraded landscapes has been proposed to support global carbon (C) mitigation measures and protect biodiversity. One of the world's largest regreening programs in the City of Greater Sudbury, Canada has… more
Year: 2023, 2023
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The accelerated recovery of base-poor soils from the legacy effects of acidic deposition may be possible by applying industrial wood ash as a soil amendment. Wood ash may be an effective soil amendment due to its high alkalinity and concentrations of several essential nutrients, such as calcium, magnesium, potassium, and phosphorus, that are retained after the volatilization of the… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Wetland loss in southern Ontario, escalated by development, is putting pressure on planners as they struggle to meet development needs while maintaining a balance with regional natural heritage. Wetland offsetting, coupled with strategic environmental assessment and sustainable community planning, offers a potential solution. A combined approach of literature review, interviews, focus… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): McDonough, Andrew Michael, Thesis advisor (ths): Watmough, Shaun A, Degree committee member (dgc): Aherne, Julian, Degree committee member (dgc): Hutchinson, Tom, Degree committee member (dgc): Sager, Eric, Degree granting institution (dgg): Trent University Abstract: <p>In this study we seek to better understand the potential effects of short-term (5-year) N fertilization on jack pine forest biogeochemistry, vascular plant community composition and to project a temporal endpoint of nitrogen leaching below the major rooting zone. Aqueous ammonium nitrate (NH4NO3) was applied above the forest canopy across five treatment plots (20 x 80 m) four times… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Decades of acidic deposition have depleted base cation pools in soil over large parts of eastern north America, including the Muskoka-Haliburton region of central Ontario. This region has also experienced a shift in forest species composition over the past 200 years, favouring sugar maple (Acer saccharum Marsh.) at the expense of species such as white pine (Pinus strobus L.) and eastern… more
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Ecological restoration helps managers of protected areas respond to challenges presented by factors that threaten ecological integrity and respond to residual effects of previous land use. Many protected areas require restoration on sections of the property, due to previous land use. The objective of this thesis is to present criteria that assist ecological restoration professionals in… more
Year: 2020, 2020
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Anthropogenic atmospheric emissions and subsequent deposition of nitrogen (N) can affect N-sensitive habitats and lead to shifts in plant species community composition. This study assessed the effects of N deposition on plant community composition for Jack pine forests across northwestern Canada and across a smaller subset of sites surrounding the Athabasca Oil Sands Region (AOSR) using… more
Year: 2020, 2020
Member of: Trent University Graduate Thesis Collection
Abstract: <p>This study examined dissolved organic matter (DOM) and labile Mercury (from diffusive gradient in thin films (DGT)) in the Quesnel river, British and the Goose creek tributary of the Churchill river, Manitoba. DOM properties were measured with optical measurements of absorption coefficient (a254), spectral slopes (S275-295, SR) and fluorescence indices (HIX, BIX, FI). The DOC proxy… more
Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The spatial and temporal variation in atmospheric nitrogen dioxide (NO2), ammonia (NH3), and 17 elements (V, Cr, Fe, Ni, Cu, Zn, As, Cd, Pb, Mg, Al, Ca, Co, Se, Sb, Mn, and Na) were measured at 40 road side locations along a ~250 km traffic density gradient of 40,000–400,000 vehicles on the King's Highway 401, in Ontario, Canada. Elemental concentrations were measured over a year,… more
Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Cowden, Phaedra, Thesis advisor (ths): Aherne, Julian, Degree committee member (dgc): Watmough, Shaun, Degree committee member (dgc): Sager, Eric, Degree committee member (dgc): Canners, Richard, Degree granting institution (dgg): Trent University Abstract: <p>Atmospheric pollutant deposition poses a risk to ecosystem health; therefore, monitoring the spatial and temporal trends of deposition is integral to environmental sustainability. Although moss biomonitoring is a common method to monitor various pollutants in Europe, offering a cost-effective approach compared to traditional methods of monitoring, it is rarely used in Canada. The focus… more
Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The Athabasca Oil Sands in Alberta, Canada is one of the largest point sources emitters of NOx in Canada and there</p><p>are concerns that elevated nitrogen (N) deposition will lead to widespread eutrophication impacts, including altered</p><p>species composition, similar to what has occurred in several parts of Europe. Atmospheric deposition rates as high as</… more
Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Samkari, Bshayer A, Thesis advisor (ths): Beresford, David, Degree committee member (dgc): Hutchinson, Tom, Degree committee member (dgc): Sager, Eric, Degree committee member (dgc): Davy, Christina, Degree granting institution (dgg): Trent University Abstract: <p>This thesis looks at the genus Pollenia: historically where they were first introduced into Canada and spatially, where they are found now. This project involved me identifying 2211 files, sorted from the 3 years of field specimens obtained in 2011, 2012, 2013. P. pediculata was the most abundant and widespread, yielding 1272 specimens out of 2211, and it was found in all provinces… more
Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>This study was designed to determine the geochemistry and potential toxicity of water draining a large slag pile in Sudbury, Ontario, which runs through a pond complex prior to entering Alice Lake. Slag leaching experiments confirmed slag is a source of sulphate, heavy metals (including Fe, Al, Ni, Co, Cu, Zn, Pb, Cr, Mn) and base cations (Ca, K, Mg, Na). Concentrations of most metals… more
Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Wild lupine (Lupinus perennis) restoration efforts seek to increase and connect populations, using seeds, to facilitate the recovery of endangered butterflys in Ontario. This study observed plant growth and phytohormone levels of L. albus, L. polyphyllus, and L. perennis through stages of seed development, each with varying strategies in growth and reproductive investment. L. polyphyllus… more
Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Timber harvest can influence the rate of transfer of organic matter from the terrestrial catchment to streams, which may have both direct and indirect effects on in-stream nutrient pools and dynamics. In the interest of developing sustainable forestry practices, the continued study of the effects of forestry on nutrient dynamics in aquatic systems is paramount, particularly in sensitive… more
Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Tree harvesting alters nutrient cycling and removes nutrients held in biomass, and as a result nutrient availability may be reduced, particularly in naturally oligotrophic ecosystems. Selection harvesting is a silvicultural technique limited to tolerant hardwood forests where individual or small groups of trees are removed creating a "gap" in the forest canopy. In order for… more
Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Invasive aquatic plants can create negative ecological, economic and social impacts when they displace local vegetation, interfere with shipping and navigation and inhibit water-based recreational activities. In 2008, the first North American occurrence of the invasive plant Stratiotes aloides (Water soldier) was identified in the Trent River, Ontario. This research measured offset… 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>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
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: 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
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: 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>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): 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