English
Understanding Dimensions of Environmental Sustainability in a Northern Indigenous Context: From Local Values to Strategies
Although the concept of environmental sustainability has become increasingly popular, the literature offers little practical guidance to direct priorities or actions to support environmental sustainability in northern Indigenous communities. A case study in Hopedale, Nunatsiavut, and a systematic literature review was undertaken to understand: 1) what aspects of the local environment are of value to a northern Indigenous community; and 2) what does existing literature identify as key elements of a community-based approach to monitor valued aspects of the environment in a northern Indigenous context. Hopedale residents spoke to the importance of going off on the land and identified a number of categories of places in their local environment of importance to them, including: 1) valued areas for human-use, 2) areas to protect, 3) areas of environmental concern, and 4) areas to monitor. The systematic literature review highlighted trends on community-based monitoring (CBM) publications, and identified key 13 elements of CBM approaches that are pertinent to northern Indigenous communities. Insights from this study will inform environmental planning and management in the case community of Hopedale, as well as offer guidance to enhance current and future CBM activities in the North and elsewhere.
Author Keywords: community-based monitoring, environmental sustainability, Inuit, Labrador, participatory mapping, systematic literature review
Sexual Dimporphism and Population Dynamics of Sub-Arctic Breding Dunlin (Calidris alpina hudsonia) near Churchill, Manitoba, Canada
Around the world, many populations of migratory shorebirds appear to be declining. Conservation strategies to reverse declining trends rely on, among other information, a firm understanding of breeding ground population dynamics. From 2010 to 2014, I studied a breeding population of Dunlin (Calidris alpina hudsonia) near Churchill, Manitoba using mark-recapture methods. I found that females were significantly larger than males. I subsequently developed an equation based on morphological features that successfully classified 87.1% of females and 92.6% of males, sexed using molecular techniques. Using program MARK, I quantified the annual apparent survival of adults (± SE) within the breeding population (0.82 ± 0.063 for males, 0.73 ± 0.12 for females). Transient adults made up a significant percentage of the female population (32%, P = 0.011), but non-significant in the male population (12%, P > 0.05). Re-sight rate was high for both sexes, and ranged from 0.86-0.90 per year. Sex, year, and nest initiation date were the factors that had the greatest influence on annual returns. There was no significant difference in mean inter-annual nest site distance between sexes (male: 82.01 ± 13.42 m, female: 208.38 ± 55.88 m, P > 0.05). The high survival estimates obtained in this study suggest that the breeding population is stable and may not be contributing to suspected population declines within the subspecies.
Author Keywords: demography, discriminant function analysis, mark-recapture, sexual size dimorphism, survival
Nature without Balance: Ideology in Times of Ecological Crisis
This thesis critically analyses the connection between ideology and nature, and in particular, aims to reflect on the dominant discourses on the topic of ecological crisis. The ecological thought framework that I adhere to rests on a combination of Frankfurt School and Žižekian theories. This combination is not without serious tensions and deviations; however, central to this project are the ways in which their respective works extensively critique ideology, and propose subversive alternatives to and new meanings of how we can conceptualize nature without domination. Dominant ideas and critiques of nature and natural history emerged during the Enlightenment era, and as Adorno argues, fell victim to a "reduction ad hominem," or the claim that in order to free oneself, one must dominate, appropriate, and master nature. I claim that the extreme choices in environmental politics today - namely organic populism on one hand and increased technological intervention on the other - fail to account for the ways 'nature' is a socio-historical construct, and moreover, is situated within a false reality wherein the 'essence of existence' is reduced to technological mastery. What we encounter in this cautionary armoury of paradoxical approaches to nature, then, is the ideological currents of established belief systems. By exposing the illusions within the concept nature, such as the argumentative persuasion that there exists an inherent balance, the elementary cell of ideology reveals itself alongside revolutionary possibilities.
Author Keywords: Crises, Critical Theory, Ideology, Nature, Slavoj Zizek, Theodor Adorno
Groundwater Recharge in a Managed Forest on the Oak Ridges Moraine, Southern Ontario
Groundwater recharge was estimated and compared in two open grasslands, three mixed deciduous forest stands (100+ years in age), three young red pine plantations (27 ¨C 29 years in age) and two old red pine plantations (62 ¨C 63 years in age) on the Oak Ridges Moraine, southern Ontario, Canada. Recharge was estimated using a 1-d water balance with measured precipitation, throughfall, stemflow, snowpack water equivalent and soil water storage, and modelled evapotranspiration. Throughfall distribution beneath red pine canopies showed no consistent variation with distance from the tree boles. Old red pines were not major stemflow producers and although the young red pines showed a slight tendency to focus stemflow (focussing ratio > 1), the inclusion of focussed stemflow when calculating recharge at the stand scale made little difference. Conversely, sugar maple (the predominant species in the mixed deciduous stands) showed a strong tendency to focus throughfall proximal to tree boles and produce large quantities of stemflow, resulting in relatively high soil moisture contents and enhanced opportunities for recharge within ~ 0.5 m of tree boles. Inclusion of these focussed inputs resulted in a ~ 11 ¨C 18 % increase in stand scale recharge estimates. The interpretation of land cover control on recharge was complicated by variations in soil texture between sites. Soil texture and its influence on soil water storage capacity resulted in temporal variations in recharge, with sites exhibiting large storage capacities producing less recharge in the fall and greater recharge in the spring than sites with limited storage capacities. Recharge estimates for the entire study period or seasonal values for sites grouped on the basis of soil water storage capacities showed a general trend of increasing recharge in the order: old red pine ¡Ö young red pine ¡ú mixed deciduous forest ¡Ö open grasslands. The disparity between the red pine plantations and the other sites was driven in large part by greater modelled evapotranspiration in the red pine plantations. The similarity in recharge between mixed deciduous forests and open grasslands was the result of focused inputs and less soil evaporation and transpiration in the mixed deciduous forests compared to the open grasslands. The results of this study suggest planting red pine on grasslands on the Oak Ridges Moraine will initially decrease recharge and this decrease will continue as the red pines mature. However, as the red pine plantations are succeeded by mixed hardwood stands recharge will recover to that of the initial grasslands.
Author Keywords: Groundwater Recharge, Land Cover Type, Oak Ridges Moraine, Stemflow, Throughfall, Water Balance
Expression and characterization of cytochrome b5 from Giardia lamblia
Giardia lamblia is an intestinal parasite found globally in freshwater systems that is responsible for endemic outbreaks of infectious diarrhea. As a unicellular parasite that lacks mitochondria, a respiratory chain and lives in the anaerobic environment of its host's intestine, Giardia was assumed for decades to lack heme proteins. However, its genome encodes several putative heme proteins, including three with sequence similarity to the cytochrome b5 family, referred to as Giardia cytochromes b5 (gCYTb5). Recombinant expression of one of these genes (gCYTb5-I), results in a protein (17-kDa) that is isolated with noncovalently bound heme. Resonance Raman and UV-visible spectra of gCYTb5-I in oxidized and reduced states resemble those of microsomal cytochrome b5, while sequence alignment and homology modelling supports a structure in which a pair of invariant histidine residues act as axial ligands to the heme iron. The reduction potential of gCYTb5-I measured by cyclic voltammetry is -165 mV vs the standard hydrogen electrode and is relatively low compared to those of other family members. The amino- and carboxy-terminal sequences that flank the central heme-binding core of the gCYTb5 are highly charged and do not occur in other family members. An 11-kDa core gCYTb5-I variant lacking these flanking sequences was also able to bind heme; however, we observe very poor expression of this truncated protein as compared to the full-length protein.
Author Keywords: b-type cytochrome, cytochrome b5, electron transfer protein, Giardia intestinalis, heme/heam protein, spectroelectrochemistry
The origin and ecological function of an ion inducing anti-predator behaviour in Lithobates tadpoles
Chemical cues are used commonly by prey to identify predation risk in aquatic environments. Previous work has indicated that negatively-charged ions of m/z 501 are possibly a kairomone that induces anti-predator responses in tadpoles. This thesis found that this ion species: (i) is produced by injured tadpoles; (ii) exhibits increased spectral intensity with higher tadpole biomass; and (iii) is not produced by starved predators. These results refute the hypothesis that the ion is a kairomone, and rather support its role as an alarm cue released from tadpoles. High resolution mass spectrometry (HR-MS) revealed a unique elemental composition for [M-H]-, m/z 501.2886, of C26H45O7S-. Collision induced dissociation (CID) of ion m/z 501 formed product ions of m/z 97 and m/z 80, HSO4- and SO3-, respectively, indicating the presence of sulfate. Green frog (Lithobates clamitans) tadpoles exposed to m/z 501, and an industrial analogue, sodium dodecyl sulphate (NaC12H25O4S), exhibited similar anti-predator responses, thereby suggesting the potential role of organic sulfate as a tadpole behavioural alterant.
Author Keywords: Alarm cue, Amphibian, Chemical Ecology, Mass spectrometry, Predator-prey interactions
Comparative phylogeography in conservation biology: unravelling the evolutionary histories of disjunct and invasive species around the Laurentian Great Lakes
Phylogeographic histories of taxa around the Great Lakes region in North America are relevant to a range of ongoing issues including conservation management and biological invasions. In this thesis I investigated the comparative phylogeographic histories of plant species with disjunct distributions and plant species with continuous distributions around the Great Lakes region; this is a very dynamic geographic area with relatively recent colonisation histories that have been influenced by a range of factors including postglacial landscape modifications, and more recently, human-mediated dispersion. I first characterized four species that have disjunct populations in the Great Lakes region: (Bartonia paniculata subsp. paniculata, Empetrum nigrum, Sporobolus heterolepis, and Carex richardsonii). Through comparisons of core and disjunct populations, I found that a range of historical processes have resulted in two broad scenarios: in the first scenario, genetically distinct disjunct and core populations diverged prior to the last glacial cycle, and in the second scenario more recent vicariant events have resulted in genetically similar core and disjunct populations. The former scenario has important implications for conservation management. I then characterized the Typha species complex (T. latifolia, T. angustifolia, T. x glauca), which collectively represent species with continuous distributions. Recent microevolutionary processes, including hybridization, introgression, and intercontinental dispersal, obscure the phylogeographic patterns and complicate the evolutionary history of Typha spp. around the Great Lakes region, and have resulted in the growing dominance of non-native lineages. A broader geographical comparison of Typha spp. lineages from around the world identified repeated cryptic dispersal and long-distant movement as important phylogeographic influences. This research has demonstrated that comparisons of regional and global evolutionary histories can provide insight into historical and contemporary processes useful for management decisions in conservation biology and invasive species.
Author Keywords: chloroplast DNA, conservation genetics, disjunct populations, invasive species, phylogeography, postglacial recolonisation
Utilizing Class-Specific Thresholds Discovered by Outlier Detection
We investigated if the performance of selected supervised machine-learning techniques could be improved by combining univariate outlier-detection techniques and machine-learning methods. We developed a framework to discover class-specific thresholds in class probability estimates using univariate outlier detection and proposed two novel techniques to utilize these class-specific thresholds. These proposed techniques were applied to various data sets and the results were evaluated. Our experimental results suggest that some of our techniques may improve recall in the base learner. Additional results suggest that one technique may produce higher accuracy and precision than AdaBoost.M1, while another may produce higher recall. Finally, our results suggest that we can achieve higher accuracy, precision, or recall when AdaBoost.M1 fails to produce higher metric values than the base learner.
Author Keywords: AdaBoost, Boosting, Classification, Class-Specific Thresholds, Machine Learning, Outliers
Reassessing Bioarchaeological Sex Determination and Research into Gender at the Early Anglo-Saxon Worthy Park Burial Ground Round in Hampshire, England
When bioarchaeologists investigate ancient gender identity, they typically place skeletal remains into one of six sex assessment categories: male, female, possible/probable male, possible/probable female, ambiguous, and indeterminate. However, the study samples are often reduced to male and female reproducing a male/female gender and sex binary prevalent in the "Western" cultural milieu and bioarchaeology when inferences are made about gender and sex in the past.
In order to allow for the existence of non-binary cultural genders and biological sexes, this thesis: 1) demonstrates the multitude of ethnographic, ethnohistoric, historic, and medical evidence relating to non-binary sex and gender expression; 2) tests a method inspired by Whelan (1991) that looks at gender as an identity not fully inspired by biological sex; 3) keeps all sex assessment categories used by bioarchaeologists separate in analysis and interpretation; and 4) analyses patterns relating to all available material culture and biological attributes in a mortuary sample to investigate gender identity.
This thesis used the Early Anglo-Saxon (470-600 AD) burial ground at Worthy Park in Hampshire to achieve these objectives. This thesis found that when examining all sex assessment categories among all mortuary variables, only the male sex was clearly defined by its mortuary assemblage. This suggests a one gender structure corresponding to linguistic evidence for one gender in Old English.
Author Keywords: Anglo-Saxon, Bioarchaeology, Gender identity, Mortuary archaeology, Osteoarchaeology, Sex determination
Detecting anti-estrogens and anti-androgens in surface waters impacted by municipal wastewater discharges and agricultural runoff
This study focused on detecting 22 target anti-estrogenic and anti-androgenic compounds in surface waters influenced by both discharges of municipal wastewater and agricultural runoff in Canada and Argentina. Polar organic chemical integrative samplers (POCIS) were used to monitor the target compounds in surface waters. The removals of the target compounds in a municipal wastewater treatment plant (WWTP) in Canada were also evaluated. In both Canada and Argentina pesticides with potential anti-estrogenic and anti-androgenic activities were detected in the surface waters. The highest concentrations were found in Argentina (up to 1010 ng L-1) in areas impacted by heavy agricultural practices. Cyproterone acetate and bicalutamide were the only two anti-cancer drugs detected only at the Canadian study site, the Speed River, ON. In the Guelph WWTP, that discharges into the Speed River, these target compounds were not all efficiently removed (>70%) during treatment. Overall, this study provides insight to possible anti-estrogenic and anti-androgenic compounds that may be contributing to endocrine disrupting activities in surface waters.
Author Keywords: Anti-androgens, Anti-estrogens, Cancer Therapy Drugs, Current use pesticides, Pharmaceuticals and Personal Care Products, Polar Organic Chemical Integrative Samplers