Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Abstract: <p>In Ontario, farmers commonly use a MZ (Maize (Zea mays L.))-SB (Soybean (Glycine max))/WW (Winter wheat (Triticum aestivum)) – CC (mixed cover crop) rotation to maximize economic benefits. This study aimed to investigate the short-term impacts of the crop rotation phases and their associated management practices in this diversified cash crop rotation on soil health and the abundance of… more Full Text: SOIL HEALTH AND SOIL MICROBIAL RESPONSES TO CASH CROP MANAGEMENT IN ONTARIO A Thesis Submitted to the Committee on Graduate Studies In Partial Fulfillment of the Requirements for the Degree of Master of Science in the Faculty of Arts and Science TRENT …
Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Eutrophication is an ongoing global problem and agriculture is an important non-point source of nutrient loading. Specifically, nitrogen (N) and phosphorus (P) losses from agricultural landscapes continue to drive water quality issues. In southern Ontario, agriculture has intensified in recent decades, with major expansions of cash crop production and extensive tile drainage (TD).… more Full Text: Effects of tile drainage, seasonality, and cash crop rotation on edge-of-field nitrogen and phosphorus losses from southern Ontario Watersheds A thesis submitted to the Committee on Graduate Studies In partial fulfillment of these thesis requirements for …
Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Agricultural and urban land uses have been linked to the recent resurgence of eutrophication and salinization issues in the lower Great Lakes. This thesis examined the relationship between watershed land use and stream nitrate-nitrogen (NO3-N), total phosphorus (TP), and chloride (Cl) concentrations across southern Ontario. Using a self-organizing map analysis, the watersheds were… more Full Text: EVALUATING THE RELATIONSHIPS BETWEEN LAND USE AND STREAM NUTRIENT AND CHLORIDE CONCENTRATIONS ACROSS SOUTHERN ONTARIO A thesis submitted to the Committee of Graduate Studies in partial fulfilment of the requirements for the Degree of Master of Science in …
Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Glyphosate burndown and tillage, followed by the cultivation of cash crops, are frequently used techniques in LUC from perennial cropping systems (PS) to annual cropping systems (AS). Agricultural LUC can result in the loss of soil nitrogen (N) via emission of nitrous oxide (N2O), a potent greenhouse gas (GHG). The purpose of this thesis is to investigate the short-term impacts of… more Full Text: SHORT-TERM IMPACTS OF AGRICULTURAL LAND USE CHANGE ON SOIL HEALTH AND NITROGEN CYCLING MICROBIAL COMMUNITIES A Thesis Submitted to the Committee on Graduate Studies In Partial Fulfillment of the Requirements for the Degree of Master of Science in the …
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 Full Text: Short-term biogeochemical response of hardwood forest soils to wood ash additions in central Ontario A Thesis Submitted to the Committee of Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Master of Science in the Faculty of …
Year: 2022, 2022
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): DeBues, Max, Thesis advisor (ths): Eimers, Catherine, Degree committee member (dgc): Watmough, Shaun, Degree committee member (dgc): Mohamed, Mohamed, Degree committee member (dgc): Mueller, Jessica, Degree granting institution (dgg): Trent University Abstract: <p>Row crop agriculture and associated land use practices including tile drainage and conservation tillage have been cited as a probable cause of re-emerging eutrophication in the
lower Great Lakes. In this thesis, I sought to quantify and evaluate the effect of agricultural land
cover and land use changes on total phosphorus (TP) and nitrate-nitrogen (NO3-N)
concentrations and export in… more Full Text: THE EFFECTS OF AGRICULTURAL LAND USE CHANGE ON NITROGEN AND PHOSPHORUS IN NORTH SHORE LAKE ONTARIO TRIBUTARIES A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Master of Science in the …
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 Full Text: The influence of tree species litterfall on soil chemistry and implications for modelling soil recovery from acidification A thesis submitted to the Committee of Graduate Studies in partial fulfillment of the requirements for the degree of Master of …
Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Lake of the Woods (LOW) is a large international waterbody which suffers from frequent and widespread algae blooms. Previous studies have highlighted the importance of the lake's largest tributary, the Rainy River (RR) and its significance in total phosphorus (TP) delivery to the LOW. Unfortunately, little is known about TP contributions from the RR and its tributaries within the… more Full Text: Phosphorus delivery in the Rainy-River Lake of the Woods Watershed A thesis submitted to the Committee on Graduate Studies in partial fulfillment of the requirements for the degree Master of Science in the Faculty of Arts and Science Trent University …
Year: 2020, 2020
Member of: Trent University Graduate Thesis Collection
Abstract: <p>This thesis examines how dissolved organic matter quantity and quality and nutrients influence the flux potential of greenhouse gases (GHG) from sediments collected from streams across southern Ontario as well as Lake Erie. Sediments were collected and incubated in a laboratory setting where headspace gases and interstitial waters were analyzed. Results demonstrated that nutrients (… more Full Text: POTENTIAL FOR GREENHOUSE GAS EMISSIONS FROM SEDIMENTS OF AGRICULTURAL STREAMS AND LAKE ERIE A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Master of Science in the Faculty of Arts and …
Year: 2020, 2020
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Thawing permafrost due to increasingly warm temperatures in northern subarctic regions is releasing mercury. The consequent formation of thaw ponds in the peatland palsa valley of the Sasapimakwananisikw (SAS) river in Whapmagoostui-Kuujjuarapik, Québec may provide a pool for MMHg formation and a potential risk to aquatic and human life, if these ponds facilitate MMHg export through… more Full Text: ASSESSING LIMNOLOGICAL CHARACTERISTICS OF SUBARCTIC QUÉBEC THAW PONDS AND MERCURY METHYLATION AND METHYLMERCURY DEMETHYLATION WITHIN THEIR SEDIMENTS A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirements for the …
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 Full Text: Near-road assessment of traffic related air pollutants along a major highway in Southern Ontario A thesis submitted to the Committee of Graduate Studies in partial fulfillment of the requirements for the degree Master of Science in the Faculty of Arts and …
Year: 2018, 2018
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): Eimers, Catherine, Degree committee member (dgc): Whitfield, Colin, Degree granting institution (dgg): Trent University Abstract: <p>In 2012, the Rio Tinto aluminum smelter in Kitimat, British Columbia increased sulphur dioxide (SO2) emissions from 27 to 42 tonnes/day. An initial study was conducted to investigate the effect of the increased sulphur (S) deposition on forest soils. A key uncertainty of the initial study was mineral surface area estimations that were applied to critical load calculations. The current… more Full Text: Estimating mineral surface area and acid sensitivity of forest soils in, Kitimat, British Columbia A thesis submitted to the Committee of Graduate Studies in partial fulfillment of the requirements for the degree of Master of Science in the Faculty of …
Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Stream solutes are strongly linked to hydrology, and as such, we sought to better understand how hydrology, particularly flooding, influences nitrogen (N) and phosphorus (P) levels. We used a long-term dataset of monthly water quality samples for many Ontario, Canada, catchments to assess the effects of landscape variables, such as land use and physiography, on the export of nutrients… more Full Text: HYDROLOGICAL AND FLOODING EFFECTS ON STREAM NUTRIENT LEVELS A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Master of Science in the Faculty of Arts and Science Trent University …
Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Preston, Colette Alexia, Thesis advisor (ths): McKenna Neuman, Cheryl, Degree committee member (dgc): Boulton, Wayne, Degree committee member (dgc): Buttle, James, Degree committee member (dgc): Eimers, Catherine, Degree granting institution (dgg): Trent University Abstract: <p>A series of experiments was designed to assess the relative efficacy of various dust suppressants to suppress PM10 emissions from nepheline syenite tailings. The experiments were conducted in the Trent University Environmental Wind Tunnel, Peterborough, Ontario, and on the tailings ponds at the Unimin Ltd Nephton mine near Havelock, Ontario. Treated surfaces were subjected to particle-… more Full Text: A wind tunnel and field evaluation of the efficacy of various dust suppressants A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Master of Science in the Faculty of Arts and Science TRENT …
Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>This thesis proposes an agro-ecological zoning (AEZ) methodology of southern Ontario for the characterization and mapping of agro-ecological zones during the historical term (1981-2010), and their shifts into the long-term (2041-2070) projected climate period. Agro-ecological zones are homogenous areas with a unique combination of climate, soil, and landscape features that are important… more Full Text: The Agro-Ecological Zoning (AEZ) of Southern Ontario and the Projected Shifts Caused by Climate Change in the Long-term Future A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Master of …
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 Full Text: The impact of selection harvesting on soil properties and understory vegetation in canopy gaps and skid roads in central Ontario A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Master of …
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 Full Text: The effects of in-stream woody debris from selective timber harvest on nutrient pools and dynamics within Precambrian Shield streams A Thesis submitted to the Committee of Graduate Studies in Partial Fulfillment of the Requirements for the Degree of …
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 Full Text: Phosphorus deposition in forested watersheds: importance of pollen A Thesis submitted to the Committee on Graduate Studies in Partial Fulfillment of the requirements for the Degree of Master of Science in the Faculty of Arts and Science TRENT UNIVERSITY …
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 Full Text: Soil mineralizable nitrogen as an indicator of soil nitrogen supply for grain corn in southwestern Ontario A Thesis submitted to the Committee of Graduate Studies in Partial Fulfillment of the requirements for the Degree of Master of Science in the …
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 Full Text: CO2 dynamics of tundra ponds in the lowArctic, Northwest Territories, Canada A Thesis submitted to the Committee on Graduate Studies in partial fulfillment of the requirements for the Degree of Master of Science in the Faculty of Arts and Science TRENT …
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 Full Text: Seasonal variation in nutrient and particulate inputs and outputs at an urban stormwater pond in Peterborough, Ontario A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Master of Science …
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p>This thesis focuses on the design of a modelling framework consisting of loose-coupling of a sequence of spatial and process models and procedures necessary to predict future flood events for the years 2030 and 2050 in Tabasco Mexico. Temperature and precipitation data from the Hadley Centers Coupled Model (HadCM3), for those future years were downscaled using the Statistical Downscaling… more Full Text: ADAPT: AN AUTOMATED DECISION SUPPORT TOOL FOR ADAPTATION TO CLIMATE CHANGE-DRIVEN FLOODS PREDICTED FROM A MULTISCALE AND MULTI-MODEL FRAMEWORK Predicting flood extents in Tabasco Mexico A Thesis Submitted to the Committee on Graduate Studies in Partial …
Year: 2013, 2013
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Winter nutrient export from forested catchments is extremely variable from year-to-year and across the landscape of south-central Ontario. Understanding the controls on this variability is critical, as what happens during the winter sets up the timing and nature of the spring snowmelt, the major period of export for water and nutrients from seasonally snow-covered forests. Furthermore,… more Full Text: Hydroclimatic and spatial controls on stream nutrient export from forested catchments A Dissertation Submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in the Faculty of Arts …
