English

Habitat selection by sympatric Canada lynx (Lynx canadensis) and bobcat (Lynx rufus)

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Names:
Creator (cre): Morin, Samantha, Thesis advisor (ths): Bowman, Jeff, Thesis advisor (ths): Fortin, Marie-Josee, Degree committee member (dgc): Schaefer, Jim, Degree granting institution (dgg): Trent University
Abstract:

Range expansion by the bobcat (Lynx rufus) may be contributing to range contraction by the Canada lynx (Lynx canadensis), but interactions between them are not well understood. To investigate the potential for competition, I conducted a literature review of hierarchical habitat selection by these two species. I determined that the lynx and the bobcat select different resources at the first and second orders, and that the fourth order is under-studied compared to higher orders. I therefore conducted a snow-tracking study of fine-scale habitat selection by lynx and bobcat in an area of sympatry in northern Ontario. I found that the two species selected similar resources at the fourth order, but appeared to be allopatric at the level of the home range. These results suggest that competition is unlikely to occur between lynx and bobcat, and other factors should be considered as more probable causes of the lynx range contraction.

Author Keywords: Bobcat, Canada lynx, Competition, Habitat selection, Scale, Snow tracking

2019

An Investigation of Rare Earth Element Patterns and an Application of Using Zn and Cd Isotope Ratios in Oysters to Identify Contamination Sources in an Estuary in Southern China

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Creator (cre): Ma, Lan, Thesis advisor (ths): Evans, R.D., Degree committee member (dgc): Hickie, Brendan, Degree granting institution (dgg): Trent University
Abstract:

Environmental monitoring and investigation of metal biogeochemical cycling has been

carried out in the Pearl River Estuary (PRE), an important and complex system in Southern

China. In this study, rare earth element (REE) patterns as well as isotope ratios (i.e., Zn and Cd)

were evaluated as tools to identify contamination sources in environmental compartments (i.e.,

water and suspended particles (SP)) as well as in oysters collected from estuarine sites. Results

show elevated concentrations (also called anomalies) of Pr, Nd, Dy and Ho, relative to other

REE elements, in water samples, potentially from REE recycling and other industrialized

activities in this area. Unlike water samples, no REE anomalies were found in SP or oysters,

suggesting that the dominate REE uptake pathway in oysters is from particles. Secondly, site to

site variations in Zn isotope ratios were found in water and SP, showing the complexity of the

source inputs in this area. Also, in estuarine locations, larger spatially differences in Zn isotope

ratios were found in water collected in wet season than those in dry season, which may due to

mixing of different source inputs under the water circulations in different seasons.

A series of laboratory experiments were conducted during which changes in Zn isotope

ratios were measured during uptake under varying salinity and Zn concentrations and during

depuration. Neither in vivo Zn transportation among the various tissues within the oysters nor

water exposure conditions (i.e., different salinities or Zn concentrations) caused Zn isotopic

fractionation in the oysters.

Cd and Zn isotope ratios were also determined in oysters obtained from the PRE. Large variations in Cd and Zn isotope ratios suggest that oysters were receiving contaminants from different input sources within the PRE. A consistent difference (approximately 0.67‰) was observed for Zn isotope ratios in oysters collected from the east side of the PRE compared to those from sampling locations on the western side of the PRE, suggesting different Zn sources in these two areas. Ultimately, by combining biogeochemistry with physiology, this study represents a first attempt to assess pollution status, monitor contaminants using oysters and model/identify contamination sources using both REEs and metal isotope ratios.

2019

A Socioloegal Mediation of Rave Sound System Technologies

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Creator (cre): Lilko, Matthew R, Thesis advisor (ths): O'Connor, Alan, Degree committee member (dgc): Mitchell, Liam, Degree committee member (dgc): Epp, Michael, Degree granting institution (dgg): Trent University
Abstract:

The central scholarly contribution of this dissertation develops through bringing the theories of Michel Foucault to bear in a sociolegal study of rave culture's criminalization by the United Kingdom's 1994 Criminal Justice and Public Order Act. My methodology develops rave as a cultural keyword. This keyword navigates through a quasi-materialist definition of rave as a cultural codification of sound system technologies. I theorize the way in which sociocultural discourse indexes aestheticized representations and the cultural mythologies that rave sound system's technical mediation generate. These ideas trace the facticity of the legal documentation of rave's criminalization. I inform this sociolegal history by situating Foucault's work on the genealogy of liberalism as a practical toolkit for associating the legal discourse on rave culture with the genealogy of festival. This opens up a dialogue with the work of Mikhail Bakhtin's theorizing of the festival's ambivalent political climate. Such ideas are useful in documenting rave as an enduring mimicry of the tension between State and civil society. Pieter Bruegel the Elder's 1559 painting, "The Fight Between Carnival and Lent", captures this tension beautifully. The aptness of reading rave's criminalization in relation to Bruegel's portrayal of landscape is accomplished by returning to Foucault, who defines liberalism's political technologies in relation to Judaeo-Christian precedents. I explore how these political technologies, pastoral power in particular, are helpful in tracing rave's genealogical relation to the festival's sociotechnical cartography.

Author Keywords: Bakhtin, Carnival, Christianity, Festival, Liberalism, Materialism

2019

Contemporary adaptive shifts in the physiology and life history of Pumpkinseed (Lepomis gibbosus) introduced into a warm climate

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Creator (cre): Rooke, Anna Christine, Thesis advisor (ths): Fox, Michael G, Degree committee member (dgc): Burness, Gary, Degree committee member (dgc): Reid, Scott, Degree granting institution (dgg): Trent University
Abstract:

Contemporary evolution has the potential to help limit the biological impact of rapidly changing climates, however it remains unclear whether wild populations can respond quickly enough for such adaptations to be effective. In this thesis, I used the introduction of native North American Pumpkinseed (Lepomis gibbosus) into the milder climate of Europe over 140 years ago, as a 'natural' experiment to test for contemporary evolution to a change in climate in wild populations. In 2008, four outdoor pond colonies were established in central Ontario using adult Pumpkinseed from two native Canadian populations, and two non-native populations from northeastern Spain. By raising native and non-native Pumpkinseed within a common environment, this design minimized the impact of phenotypic plasticity on differential trait expression, and allowed me to interpret differences in the phenotype among pond-reared Pumpkinseed as evidence of genetic differences among populations. I demonstrated that Canadian and Spanish Pumpkinseed have similar thermal physiology except when acclimated to seasonally warm temperatures; trait differences are consistent with Spanish Pumpkinseed being better adapted to a warmer climate. Populations also had similar overwintering ecology, however some differences, such as higher survival under starvation conditions and greater energetic benefits associated with winter feeding, indicated that Canadian populations are better adapted to harsh winter conditions typical of the native range. Finally, I determined that the relatively fast life history expressed in wild European Pumpkinseed is largely driven by plastic responses to the local environment; however, the higher reproductive investment by European populations has a genetic basis. Most climate change research considers taxa that are expected to be negatively impacted by warming: my research demonstrates that even warm-tolerant taxa that are unlikely to experience strong climatic selective forces can respond to a warming environment through evolutionary changes. The potential for adaptive contemporary evolution in warm-tolerant taxa should be taken into account when predicting future ecosystem effects of climate change, and when planning management strategies for species introduced into novel climates.

Author Keywords: climate change, contemporary evolution, fish, non-native species, thermal biology, winter ecology

2019

An Application of Virgilio Enriquez's Indigenization Method on Filipino-Canadian Discourse

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Creator (cre): Pacquing, Mykelle, Thesis advisor (ths): McCaskill, Don, Degree committee member (dgc): Newhouse, David, Degree granting institution (dgg): Trent University
Abstract:

In Disturbing Invisibility (Coloma, McElhinny, Tungohan, Catungal, Davidson, 2012), the most comprehensive book on Filipino-Canadian studies to date, issues were identified in the afterword as to how Filipino-Canadian studies relates to indigenous identity. This thesis attempts to address this issue by applying Enriquez's (1992) Indigenization Method onto Filipino-Canadian discourse. It attempts to do this by: exploring the colonial context and history in the Philippines and its effect on the formation of a Filipino indigenous identity; exploring Filipino indigenous thought as described by Enriquez (1992) in his seminal book From Colonial to Liberation Psychology; understanding Filipinos in Canada with the inclusion of literature from Filipino-American studies and the Filipino Indigenization movement; and how orienting Filipino-Canadian discourse with the indigenous concepts brought forward by Enriquez might look like, with emphasis on how Filipino-Canadian discourse could interact with Indigenous issues relating to Indigenous People in Canada today. It becomes clear that the Filipino Indigenization movement has reached grassroots Filipino organizations in Canada, and that uncritically ignoring their own Filipino indigenous roots would be denying themselves the unique cultural gifts that those roots provide. As being both Filipino and Canadian, Filipino-Canadians who seek to reclaim their indigenous roots would find that the indigenous concept of kapwa ("the self in the other") would encourage an examination of issues pertaining to Indigenous People in Canada as commonalities exist in their experiences with colonization.

Author Keywords: Canada, discourse, Filipino-Canadians, indigenization, indigenous, Philippines

2019

Molecular Composition of Dissolved Organic Matter Controls Metal Speciation and Microbial Uptake

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Creator (cre): Mangal, Vaughn, Thesis advisor (ths): Gueguen, Celine, Degree committee member (dgc): Poulain, Alexandre J, Degree committee member (dgc): Rafferty, Steven, Degree granting institution (dgg): Trent University
Abstract:

Aquatic contaminant mobility and biological availability is strongly governed by the complexation of organic and inorganic ligands. Dissolved organic matter (DOM) is a complex, heterogeneous mixture of organic acids, amino acids, lipids, carbohydrates and polyphenols that vary in composition and can complex to dissolved metals thereby altering their fate in aquatic systems. The research conducted in this doctoral dissertation addresses 1) how DOM composition differs between phytoplankton taxa and 2) how DOM composition affects metal speciation and its subsequent microbial bioavailability in laboratory and field conditions. To accomplish this, a series of analytical methods were developed and applied to quantify thiols, sulphur containing DOM moieties, and the molecular composition of DOM. The works presented in this thesis represents one of the first comprehensive and multipronged analyses of the impact of phytoplankton metabolite exudates on microbial metal bioavailability. This dissertation demonstrated the analytical versatility of high-resolution mass spectrometry as a tool for compound specific information, as well as having the capabilities to obtain speciation information of organometallic complexes. The work presented in this PhD strengthens the understanding compositional differences of both autochthonous and allochthonous DOM and their effects on metal biogeochemistry.

Author Keywords: Dissolved Organic Matter, Mercury, Metal Accumulation, Phytoplankton, Spring Melts, Thiol

2019

Disease ecology of ophidiomycosis in free-ranging snakes

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Creator (cre): Dillon, Rachel, Thesis advisor (ths): Davy, Christina M, Thesis advisor (ths): Bowman, Jeff, Degree committee member (dgc): Donaldson, Michael, Degree granting institution (dgg): Trent University
Abstract:

Ophidiomycosis (snake fungal disease) is caused by the pathogen Ophidiomyces ophiodiicola. Infected snakes exhibit dermal lesions, occasional systemic infections, and, in some cases, mortality. We studied snakes at Rondeau Provincial Park, Ontario, Canada, to explore whether ophidiomycosis develops during brumation or year-round. Throughout their active season, we quantified the prevalence of clinical signs of the disease on snakes and conducted qPCR of skin swabs to determine the prevalence of O. ophiodiicola on snakes. Prevalence of O. ophiodiicola and disease symptoms were highest on eastern foxsnakes (Pantherophis vulpinus) and very rare on other snake species. In P. vulpinus, pathogen and clinical sign prevalence was highest, directly after emergence from overwintering, with the majority of P. vulpinus being able to resolve clinical signs of ophidiomycosis by the return of winter. When we analyzed the survivorship of P. vulpinus we determined that the likelihood of a snake dying with ophidiomycosis is similar to a snake dying without ophidiomycosis. Given that P. vulpinus were the most affected species at our study site, ophidiomycosis does not appear to pose an imminent threat to our study population of P. vulpinus under current conditions.

Author Keywords: Eastern Foxsnake, Fitness, Ophidiomycosis, Pantherophis vulpinus, Seasonal trends, Snake fungal disease

2020

Sowing the seeds of Canada's future agroecological farm(er)s: Farm incubators and experiential sustainable agriculture education

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Creator (cre): Denis, Willow, Thesis advisor (ths): Rutherford, Stephanie, Thesis advisor (ths): Hutchinson, Thomas, Degree committee member (dgc): Classens, Michael, Degree granting institution (dgg): Trent University
Abstract:

There are many barriers facing new, sustainably-focused, agriculturalists in Canada including access to land, capital, markets and practical training. These challenges are compounded by the flawed but powerful figure of the industrial agriculture model, a rapidly aging farmer population, changing demographics, and subsequent loss of valuable, place-based agricultural knowledge. This thesis argues that there is a need for innovative formal education programs that combine traditional classroom with practical hands-on learning in collaboration with local experts. As such, this exploratory case study looks at how a farm incubator can function as a site for experiential education and a means of addressing some of the barriers to entry faced by new agroecological farmers. The findings show that those seeking experiential sustainable agriculture education benefit greatly from having a site, such as a farm incubator, to learn the skills that accompany their knowledge while building their agricultural community and increasing their confidence.

Author Keywords: agroecology, experiential learning, farm incubators, social learning, sustainable agriculture and food systems education, transdsciplinary

2020

Effects of wood ash addition on soil chemical properties and sugar maple (Acer saccharum, Marsh.) seedling growth in two northern hardwood forest sites in central Ontario

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Creator (cre): Deighton, Holly, Thesis advisor (ths): Watmough, Shaun A, Degree committee member (dgc): Basiliko, Nathan, Degree committee member (dgc): Hazlett, Paul W, Degree granting institution (dgg): Trent University
Abstract:

One possible solution to acidification and losses of base cations in central Ontario forest soils may be the application of wood ash. Wood ash is generally high in pH and contains large amounts of calcium (Ca) and other nutrients essential for ecosystem health, however it also contains trace metals. Understanding the chemistry of soils following ash application to forests is crucial for future policy recommendations and remediation efforts. In this study, soil and soil water chemistry was measured at two acidic forest sites in central Ontario. Sugar maple (Acer saccharum, Marsh.) seedling growth and chemistry, as well as understory vegetation composition, were also measured. At site one, plots (2 m x 2 m) were established with sugar maple, white pine (Pinus strobus L.) and yellow birch (Betula alleghaniensis Britt.) residential wood ash treatments and applied at rates of 0 and 6 Mg ha-1. The effects of residential wood ash on soil and understory vegetation were measured three- and 12-months following ash addition. At site two, plots (5 m x 5 m) were established with both fly and bottom industrial grade bark ash treatments of 0, 4 and 8 Mg ha-1 (n=4), and tension lysimeters were positioned in each plot at 30, 50, and 100 cm depths. The effects of industrial grade wood ash on soil, soil water and understory vegetation were measured four years following ash addition. Metal concentrations in the ashes were generally low but were higher in the fly ash and yellow birch ash types. At site one, significant increase in soil pH, and Ca and magnesium (Mg) concentrations were observed after three months, however changes varied by treatment. Some metal concentrations increased in the upper organic horizons, but metals were likely immobilized in the soil due to increases in soil pH, electrical conductivity (EC) and high organic matter content of the soil. After one year, changes to metal concentrations in soils could be seen in mineral horizons, and a few metals (aluminum (Al), zinc (Zn), copper (Cu), chromium (Cr), strontium (Sr)) increased in treatment plots. At site two, the effects of industrial-grade bark ashes on soil pH could still be seen after four years and soil water metal concentrations were not elevated relative to controls. Changes to understory vegetation composition following ash application were observed, but ash addition had no significant effect on sugar maple seedling growth (root:shoot ratio) and did not lead to significant increases in foliar metal concentrations. There were significant differences in root chemistry, suggesting metal translocation and uptake could be restricted. Mass balance estimates indicate that the organic horizon is a sink for all metals and simulated drought in this horizon led to a decrease in soil pH and increase in soil water metal concentration, but this occurred in all treatments including control. These results suggest that application of industrial and residential wood ash in moderate doses with trace metal concentrations below or near regulatory limits will increase soil pH and base cation concentrations, as well as increase seedling tissue nutrient concentrations in northern hardwood forest soils. However, depending on the parent material of the ash, increased metal availability can also occur.

Author Keywords: Acer saccharum, calcium decline, forest soil amendment, Haliburton Forest and Wildlife Reserve, heavy metal, wood ash

2020

Assessing basin storage: A combined hydrometric and isotopic approach for streams draining the Oak Ridges Moraine, southern Ontario

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Creator (cre): Cooke, Ciara, Thesis advisor (ths): Buttle, James M., Degree committee member (dgc): Lafleur, Peter, Degree committee member (dgc): Metcalfe, Robert, Degree granting institution (dgg): Trent University
Abstract:

Water storage is a fundamental component of drainage basins, controlling the synchronization between precipitation input and streamflow output. The ability of a drainage basin to store water and regulate streamflow may mediate sensitivity to climate and land cover change. There is currently no agreement on the best way to quantify basin storage. This study compares results of a combined hydrometric and isotopic approach for characterizing inter-basin differences in storage across the Oak Ridges Moraine (ORM) in southern Ontario. The ratio of the standard deviation of the stable isotope signature of streamflow relative to that of precipitation has been shown to be inversely proportional to mean water transit times, with smaller ratios indicating longer water transit times and implying greater storage. Stable isotope standard deviation ratios were inversely related to baseflow index values. Basins demonstrating longer transit times were associated with hydrological characteristics that promote infiltration and recharge of storage.

Author Keywords: baseflow, basin storage, climate change, mean transit time, Oak Ridges Moraine, stable isotopes

2020