Year: 2023, 2023
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Annan, Melanie Joslyn, Thesis advisor (ths): Frost, Paul C, Degree committee member (dgc): Koprivnjak, Jean-François, Degree committee member (dgc): Bailey, Robert, Degree committee member (dgc): Raby, Graham, Degree granting institution (dgg): Trent University Abstract: <p>In situ chlorophyll sensors are beneficial for monitoring of long-term impacts of algal blooms and accessing water quality issues in bodies of water. However, more research is needed to validate their efficacy and understand how environmental conditions can influence sensor measurements. I assessed the performance of an in situ chlorophyll sensor under controlled environmental conditions… more Full Text: IN SITU CHLOROPHYLL MEASUREMENTS WITH FLUOROMETRY: IN-LAB VALIDATION AND USE IN LAKE VERTICAL PROFILING A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfilment of the Requirements for the Degree of Master of Science in the Faculty of …
Year: 2020, 2020
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Warming climates have had various consequences on terrestrial and aquatic food webs that are expected to persist. There is evidence suggesting that certain organisms are better equipped to handle changing climates compared to others. Therefore, the purpose of my thesis was to study the adaptability of Daphnia under temperature stress and nutrient limitation. First, to examine the effects… more Full Text: DAPHNIA PULICARIA RESPONSES TO TEMPERATURE AND NUTRIENTS STRESS: WHAT HAPPENS WHEN THE HEAT IS ON? 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 …
Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>While both resource quality and predator-derived chemical cues can each have profound effects on zooplankton populations and their function in ecosystems, the strength and nature of their interactive effects remain unclear. We conducted laboratory experiments to evaluate how stoichiometric food quality (i.e., algal carbon (C):phosphorus (P) ratios) affects responses of the water flea,… more Full Text: STOICHIOMETRIC FOOD QUALITY AFFECTS RESPONSES OF DAPHNIA TO PREDATOR-DERIVED CHEMICAL CUES 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: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Leaf litter decomposition represents a major pathway for nutrient cycling and carbon flow in aquatic ecosystems, and macroinvertebrates play an important role in the processing of this material. To assess the causes of variable leaf breakdown and nutrient fluxes, I measured decomposition rates and the nutrient release ratios of decomposing leaf material across a broad latitudinal… more Full Text: AQUATIC INVERTEBRATE STUDIES FROM TWO PERSPECTIVES: FUNCTION (SHREDDERS) AND DISTRIBUTION (DYTISCIDAE) 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 …
Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The network composition hypothesis (NCH) suggests that i) large confluence symmetry ratios (drainage area of the tributary relative to the mainstem) and ii) landscape differences (differences in landscape characteristics between the mainstem and tributary drainages) lead to greater ecological changes below confluences. As a test of the NCH, 34 confluences were sampled in southern Ontario… more Full Text: DISCONTINUITIES IN STREAM NETWORKS: THE EFFECTS OF TRIBUTARY SIZE AND TYPE ON BENTHIC INVERTEBRATE COMMUNITIES DOWNSTREAM FROM CONFLUENCES A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirements for the Degree of …
Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Daphnia are keystone consumers in many pelagic ecosystems because of their central role in nutrient cycling. Daphnia are also frequently infected, and the parasites causing these infections may rival their hosts in their ability to regulate ecosystem processes. Therefore, parasitic exploitation of Daphnia may alter nutrient cycling in pelagic systems. This thesis integrates existing… more Full Text: THE EFFECTS OF PARASITISM ON CONSUMER-DRIVEN NUTRIENT RECYCLING A dissertation submitted to the Committee in Graduate Studies in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Faculty of Arts and Science TRENT …
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 Full Text: Effects of biodiversity and lake environment on the decomposition rates of aquatic macrophytes in the Kawartha Lakes, Ontario A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Degree of …
Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Environmental variation can affect consumer trait expression and alter ecological and evolutionary dynamics in natural populations. However, although dietary nutrient content can vary by an order of magnitude in natural ecosystems, intra-specific differences in consumer responses to food quality have not been thoroughly investigated. Therefore, the purpose of my dissertation was to… more Full Text: ELEMENTAL VARIATION IN DAPHNIA: NUTRITIONAL, GENETIC, AND ENVIRONMENTAL FACTORS A Thesis 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 and Science …
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 Full Text: NUTRIENT METABOLISM OF AN AQUATIC INVERTEBRATE AND ITS IMPORTANCE TO ECOLOGY A Thesis 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 and Science Trent …
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 Full Text: A MECHANISTIC ANALYSIS OF DENSITY DEPENDENCE IN ALGAL POPULATION DYNAMICS 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>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 Full Text: Effects of Silver Nanoparticles on Lake Bacterioplankton 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: 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 Full Text: Nutritional stoichiometry and growth of filamentous green algae (Family Zygnemataceae) in response to variable nutrient supply A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Master of …