Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Threats such as climate change and increased anthropogenic activity such as shipping, are expected to negatively affect the Arctic. Lack of data on Arctic systems restricts our current understanding of these sensitive systems and limits our ability to predict future impacts. Lakes and ponds are a major feature of the Arctic landscape and are recognized as 'sentinels of change… more Full Text: Hydrochemistry and critical loads of acidity for lakes and ponds in the Canadian Arctic 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 Arts and …
Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>A catchment-based study was carried out at three remote acid sensitive Irish lakes to determine concentrations of Hg and POPs and to investigate the factors governing the partitioning of these pollutants in various environmental matrices. Both Hg and POPs are an environmental concern due to their ability to travel long distances via atmospheric transport and their tendency to accumulate… more Full Text: Mercury and Persistent Organic Pollutants in Remote Acid Sensitive Irish Lake Catchments 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 Arts and …
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 Full Text: In situ measurements of trace metal species in the Athabasca and Mackenzie Rivers using diffusive gradient in thin films (DGT) devices A Thesis submitted to the Committee of Graduate Studies in Partial Fulfillment of the Requirements for the Degree of …
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 Full Text: A C I D I F I C AT I O N O F L A K E S I N N O R T H E R N S A S K AT C H E WA N AN ASSESSMENT OF SENSITIVITY AND RISK FROM ACIDIC DEPOSITION A Thesis Submitted to the Committee of Graduate Studies in Partial Fulfillment of the Requirements for the Degree …
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 Full Text: Calcium in the Muskoka River Watershed – Patterns, trends, the potential impact of forest harvesting on lake Ca levels and steps toward an ecosystem approach to mitigation A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfilment of …
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 Full Text: Passive sampling of indoor and outdoor atmospheric nitrogen dioxide in the greater Toronto area A Thesis Submitted to the Committee of Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Master of Science in Faculty of Arts and …
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 Full Text: A Regional Assessment of Soil Calcium Weathering Rates and the Factors that Influence Lake Calcium in the Muskoka River Catchment, Central Ontario A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfilment of the Requirements for the …
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 Full Text: Models of partitioning, uptake, and toxicity of neutral organic chemicals in fish 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 …
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 Full Text: Influence of nitrogen deposition on the vegetation community of Irish oak woodlands 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 …
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 Full Text: ASSESSING THE IMPACT OF ATMOSPHERIC DEPOSITION AND HARVEST INTENSITY ON SOIL ACIDITY AND NUTRIENT POOLS IN PLANTATION FORESTS A dissertation submitted to the Committee on Graduate Studies in partial fulfillment of the requirements for the Degree of Doctor …
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 Full Text: THE EFFECTS OF ENVIRONMENTAL VARIABLES AND DISSOLVED ORGANIC MATTER CHARACTERISTICS ON THE DIFFUSION COEFFICIENTS OF DISSOLVED ORGANIC MATTER USING DIFFUSIVE GRADIENTS IN THIN FILMS A Thesis submitted to the Committee on Graduate Studies in Partial …
