Year: 2021, 2021
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Macrophytes play an important role in aquatic ecosystems, and thus are integral to ecological risk assessments of environmental contaminants. In this dissertation, I address gaps in the assessments of contaminant fate and effects in macrophytes, with focus on glyphosate herbicide use for invasive plant control. First, I evaluated the suitability of Typha as future standard test species… more
Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Interspecific hybridization rates can vary depending on genomic compatibilities between progenitors, while subsequent hybrid spread can vary depending on hybrid performance and habitat availability for hybrid establishment and persistence. As a result, hybridization rates and hybrid frequencies can vary across regions of parental sympatry. In areas around the Laurentian Great Lakes,… more
Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The Kentucky coffee tree (Gymnocladus dioicus) is an endangered tree species native to the American Midwest and Southwestern Ontario. Significant habitat loss and fragmentation due to agricultural, industrial and urban development has caused gradual decline across its native range. The aims of this study were to investigate: (1) patterns of genetic diversity and, (2) genetic… more
Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Effective population size (Ne) is a foundational concept in conservation biology, in part due to its relationship to the adaptive potential of populations. Although Ne is often estimated for wild populations, it is rarely calibrated against actual population estimates (Nc) other than to produce Ne/Nc ratios. This project used demographic and genetic data for from two intensively-studied… more
Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The purpose of this thesis is to enhance forensic entomology applications through identifications and ecological research with samples collected in collaboration with the OPP and RCMP across Canada. For this, we focus on blow flies (Diptera: Calliphoridae) and present data collected from 2011-2013 from different terrestrial habitats to analyze morphology and species composition.… more
Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The recent northward expansion of the white-footed mouse (Peromyscus leucopus) in response to climatic changes provides a natural experiment to explore potential adaptive genetic variation within the clock gene Per1 in Peromyscus undergoing latitudinal shifts, as well as, the possibility of hybridization and introgression related to novel secondary contact with its sister species the… more
Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>There are three cattail (Typha) taxa in Canada: T. latifolia (native), T. angustifolia (introduced), and their hybrid T. x glauca. The latter is invasive in regions around the Laurentian Great Lakes, and I investigated the potential role that commercial suppliers may be playing in the introduction of non-native Typha by comparing genotypes of North American, European, and commercially… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p><italic>Magnolia acuminata</italic> (Cucumber tree) is the only native Magnolia in Canada, where it is both federally and provincially listed as endangered.<italic>Magnolia acuminata</italic> in Canada can be found inhabiting pockets of Carolinian forest within Norfolk and Niagara regions of southwestern Ontario. Using a combination of nuclear and chloroplast… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Lin, Shang-Yao Peter, Thesis advisor (ths): Dorken, Marcel E, Thesis advisor (ths): Nol, Erica, Degree committee member (dgc): Crins, William J, Degree committee member (dgc): Freeland, Joanna R, Degree granting institution (dgg): Trent University Abstract: <p>Sexual reproduction in flowering plants depends on investment in reproduction, the mode of pollen transfer, the availabilities of nutrient resources and potential mates, and the spatial scales over which these processes take place. In this thesis, I studied the general reproductive biology of Shepherdia canadensis (L.) Nutt. (Elaeagnaceae) and the suite of pollinators that visit the… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Ahee, Jordan, Thesis advisor (ths): Dorken, Marcel E, Degree committee member (dgc): Freeland, Joanna R, Degree committee member (dgc): Burness, Gary, Degree committee member (dgc): Pond, Bruce, Degree granting institution (dgg): Trent University Abstract: <p>Natural populations of flowering plants rarely have perfectly uniform distributions, so trends in pollen dispersal should affect the size of the pollination neighbourhood and influence mating opportunities. Here I used spatial analysis to determine the size of the pollination neighbourhood in a stand of the herbaceous, wind-pollinated plant (<italic>Typha latifolia</italic>;… more