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Determining plant responses to metal contamination: implications for restoration
Get PDFAnthropogenic disturbances such as industrial contamination can negatively impact peatland
plant communities, leading to reductions in their carbon-storage capacity and the number of plant communities present. One well-known example of these disturbances is the copper (Cu) and nickel (Ni) mining in Sudbury, ON. There has been a complete loss of moss species in the most highly contaminated sites, which had led to a major loss to the ecosystems’ carbon-storage capabilities. To effectively restore these contaminated peatlands, it is critical to first understand the biological impacts of metal contamination on peatland plants, especially the keystone Sphagnum mosses and Ericaceae shrubs. I assessed variation in photosynthesis, morphology, and leaf chemistry in 18 fen peatlands ranging from high disturbance to undisturbed (i.e., outside the contamination zone). This study found metal-tolerant strategies exhibited by plant species in metal-contaminated environments. These results indicate species recolonization potential in heavily contaminated sites, particularly for evergreen shrubs and Sphagnum fuscum, to restore such sites to carbon-storing states. The use of a leaf economics spectrum (LES) is valuable for understanding trait coordination in metal-contaminated peatlands, but it did not reliably predict intraspecific shifts in conservative traits for evergreen shrubs or Sphagnum. However, specific capitulum area (SCA, the ratio of moss photosynthetic area to dry mass) is presented here as a meaningful trait that links moss structure with photosynthetic function and should be incorporated into trait-based assessments in degraded peatlands
The microbial and geochemical architecture of Scotian Slope cold seep Site 2A-1, Scotian Slope, Canada
Get PDF1 online resource (xii, 153 pages) : illustrations (some colour), colour maps, charts (some colour), graphs (some colour)Includes abstract and appendices.Includes bibliographical references (pages 13-20, 32-33, 70-74, 117-124,129).Cold seeps occur globally along the seabed of continental margins, expelling reduced
fluids, which help to form oasis-like ecosystems in highly redox stratified sediments. In this study, a 600 m long, six push core, transect was collected from cold seep site 2A-1, located on the Scotian Slope of Eastern Canada. Downcore porewater ions and lipidomic profiles were generated. These data were compiled as spatially resolved, two-dimensional heatmaps to examine both vertical and lateral changes in the subsurface geochemical and microbiological architecture. Twenty-three lipid classes, predominantly of archaeal origin, were tentatively identified and quantified. Microbially mediated metabolic zones of targeted processes, were mapped based on ion porewater concentrations, diffusion fluxes, carbon isotope values, lipidomic diversity patters, and biomarker proxy data. The resolved lipidome indicates a zoned archaeal community with diversity increasing as a function of seepage rate that provides insights into the seep’s formation and microbial
dynamics
Mineral dust aerosol sources in northern Canada : an investigation using the TROPOMI instrument
Get PDF1 online resource (105 pages) : maps (some colour), charts, graphs (some colour)Includes abstract and appendices.Includes bibliographical references (pages 99-105).Mineral dust aerosols (MDAs) are important for climate regulation, but little is known about their sources in high-latitude regions like northern Canada. This thesis investigates the atmospheric distribution and surface sources of MDAs in northern Canada using the satellite-based Tropospheric Monitoring Instrument (TROPOMI). TROPOMI Absorbing Aerosol Index (AAI) and Aerosol Layer Height (ALH) data were used, together with the TROPOMI cloud cover (CLO) and carbon monoxide (CO) products. (Where CO and CLO are low, spurious impacts on AAI due to non-MDA atmospheric components are minimized.) The three main research questions were: (1) What is the distribution of dust in northern Canada, according to TROPOMI? and (1b) What does ALH data imply about the sources of the observed dust distributions? (2) How do TROPOMIderived aerosol products compare to those of other well-characterized satellite instruments, like
MODIS and OMI? (3) What are the effects of filtering the TROPOMI aerosol products by the carbon monoxide and cloud products? It was found that frequent observations of AAI values greater than 0.5 were made by TROPOMI in high-latitude regions in 2021, suggesting the presence of absorbing aerosols, likely MDAs. Filtering AAI data by ALH isolated likely local MDAsources, previously uncharacterized in field observations. It was also found that TROPOMI AAI data broadly agrees with MODIS Aerosol Optical Depth (AOD) and OMI AAI data, especially when filtered for positive TROPOMI AAI values and statistically significant correlations. Unexpectedly, filtering AAI data by low CO or CLO did not improve the correlation between TROPOMI and MODIS data, but it also did not eliminate the dust sources isolated by ALH filtering. The findings suggest the presence of significant sources of MDAs in northern Canada, but more observational research is needed to confirm their existence and strength, and thus their impact on climate
The palindrome as a disruptive force : an analysis of feminist literature in international relations (IR) rooted in the work of Cynthia Enloe
Get PDF1 online resource (41 pages)Includes abstract.Includes bibliographical references (pages 36-41).Feminists have long been championing the idea that ‘the personal is political’ and that
politics occur even in the areas of life which seem to be most apolitical. Popularized in the field of International Relations (IR) by Cynthia Enloe in her 1989 book Bananas, Beaches and Bases: Making Feminist Sense of International Politics, this palindrome has come to be used by feminist scholars throughout IR and feminist security studies (FSS). Enloe also introduced the idea that ‘the personal is international’, which is the second palindromic phrase that is explored in this essay. Able to be read both left-to-right and in an inverted manner, the palindrome is disruptive and creates an instability in language and thought, much as feminists aim to do. This essay examines six single-authored monographs which use palindromes in their analysis as a means to unsettle normative political concepts by highlighting connections between the everyday lived experiences of women and the political world, of which women are often portrayed as being outsiders. This thesis will argue that Cynthia Enloe's introduction of the palindromic phrase "the personal is
international" in her 1989 book Bananas, Beaches and Bases: Making Feminist Sense of
International Politics brings to light the role that individual authors can play in setting the course of academic research in a discipline
Examining drivers of ecomorphodynamic change in the Avon River Estuary
Get PDF1 online resource (ix, 111 pages) : colour illustrations, colour maps, colour charts, graphs (some colour)Includes abstract and appendix.Includes bibliographical references (pages 101-109).The Avon River Estuary is a hypertidal, muddy estuary in the upper Bay of Fundy. The system has been in dynamic equilibrium since construction of the causeway in 1970, but recent construction activities and changes in tide gate management have caused an observable shift to disequilibrium. To assess the environmental consequences of these activities, we examine the relative influence of natural and anthropogenic drivers of ecomorphodynamic change within the Avon River, downstream of the Highway 101 causeway by comparing data from 2019-2023 to baseline conditions, 2007-2019. We hypothesize that system ecomorphodynamics will be strongly influenced by human activities. To evaluate changes in ecomorphodynamics occurring in the system we examined changes in channel cross-sectional profiles, cross-sectional area, changes in surface elevation, volumetric changes, sediment grain size, and vegetated area. These analyses were completed primarily through ArcGIS Pro and Microsoft Excel. We then
compared these changes to tide gate manipulation information, construction activities, tidal cycles, and precipitation data to infer what may be influencing the change. Results indicate that there has been a quantifiable change in ecomorphodynamics between the baseline period and the study period. Additionally, most of the notable changes that occurred were concentrated around the Windsor Marsh and the Newport Bar, near the causeway. Based on patterns in natural and anthropogenic influences as well as the locations of changes, we believe that construction has had strong influence on the Avon River Estuary while the St. Croix River is mostly unaffected by anthropogenic interference and precipitation may be the dominant driver of change. While future studies need to be conducted and should be based closer to the causeway, these results provide insight from an environmental assessment perspective into how estuaries experiencing significant anthropogenic interference may respond and adjust
The effects of acid rain and liming on select members of the Ericaceae family
Get PDF1 online resource (iv, 72 pages) : colour maps, colour charts, colour graphsIncludes abstract.Includes bibliographical references (pages 60-72 pages).Acid rain, characterized by sulphuric acid deposition, poses threats to ecosystems, plants,
and animals across Canada. Nova Scotia has a longstanding history of acid rain, influenced by both local sources from industry and air pollution, as well as atmospheric contributions from the northeastern United States. This situation is compounded by the natural acidity of the region's soils, primarily derived from the prevalence of granite bedrock. Greater Sudbury, Ontario is a historical mining town with a long history of acid rain deposition from metal mining that destroyed local flora. Lime, administered as calcium carbonate successfully brought back Lifetree cover to Sudbury, and offers restoration potential elsewhere by neutralizing soil acidity. Despite successful applications in many Canadian forests, Nova Scotia's liming applications are limited. To address this, I applied sulphuric acid and lime to forest plots and monitored chemical, morphological and
physiological responses of understory shrubs over a single growing season. A case study was conducted in Sudbury and compared to the experimental results obtained in Nova Scotia. Responses to the treatments were species-specific, with a general reduction of functional traits for the acid treatments. Liming in the short-ter showed indicators of being a positive driver for both teaberries and sheep laurel. Comparative analysis with data from Sudbury, Ontario, plants subjected to long-term liming showed more favorable growth outcomes in limed sites. Here, liming in the long-term increased the leaf pH, calcium (Ca2+) content, and leaf dry matter content (LDMC). The long-term effects of liming were also evident in the lowbush blueberry, as shown in the increase in leaf pH and LDMC. This suggests the potential for positive lime effects on understory shrubs, possibly requiring extended periods for establishment. This study, though preliminary, provides valuable insights into using liming as a restoration strategy in regions impacted by acid rain in Nova Scotia
The wounded healer : spiritual research on feminist spiritual leadership nurtured by American Zen Buddhism
Get PDF1 online resource (261 pages) : colour illustrations, charts (some colour), graphs (some colour)Includes abstract and appendices.Includes bibliographical references (pages 241-257).My thesis tells a story of self-healing and self-empowerment, a story of how I obtain
intellectual, emotional, and spiritual growth through spiritual research on American Zen Buddhism. As a female Chinese immigrant in Canada, I have been wounded by people in power under various oppressive social systems. My deepest wound is my father’s domestic violence that I suffer throughout my childhood and youth under Chinese patriarchy. I am able to heal this wound through an autoethnographic field study at some major American Zen centers that have been afflicted with sex scandals. This transformative experience enables me to better deal with challenges in both the personal and professional realms of my life. My story is worth telling because I want to inspire
collective awakening. I know that countless people are suffering what I suffered, and I want to let them know there is a way out. My awakening experience enables me to be compassionate for all. Those who abuse others may have been abused. Those who are abused may abuse others. Who is to be healed and liberated? Everyone, regardless of gender, race, ethnicity, or anything. The wisdom and power that one needs to fight inequity and injustice lie in a healed and fearless heart. This Zen-informed spiritual research aims to address an overarching research question: How might American Zen Buddhist teaching and practice heal and empower the wounded people who manifest their healing and empowerment in their whole beings, including research approaches,
leadership theorization, teaching practices, and dealing with challenges in personal and
professional realms of life? Accordingly, my research makes four primary contributions. First, I develop a Zen-informed spiritual research paradigm that fundamentally transcends the dominant functionalist paradigm. Second, I propose a Zen-informed feminist (androgynous) spiritual leadership model that is not only gender-inclusive but also shedding light on the black box of spiritual transformation. Third, I examine the key features of American Zen teaching practice and explore a Zen-informed spiritual approach to management education that is healing and empowering to students. The fourth contribution of this research depends on its impacts on both you and me in dealing with life’s challenges: Does the research enable you and me to be aware of our hidden wounds, of our collective sufferings, and to access our inner wisdom to show up in
compassionate disruptions? Only the wounded healer is able to heal. I am an aspiring wounded healer
Creating an urban heat vulnerability index (HVI) in the face of climate change employing geospatial technology in Halifax, Canada
Get PDF1 online resource (86, 4 unnumbered pages) : colour maps, charts, graphs (some colour)Includes abstract and appendix.Includes bibliographical references (pages 69-86).Heat waves are one of the most common weather events happening in recent decades,
posing threats to public health especially in urban built-up environments. This study employs geospatial techniques to evaluate urban heat vulnerability in the city of Halifax,
Nova Scotia, Canada. The Heat Vulnerability Index (HVI) was developed through the
utilization of the Geographic Information System (GIS), integrating exposure, sensitivity,
and adaptive capacity measures generated using Remote Sensing (GIS) and socioeconomic datasets for four years covering: 2006, 2011, 2016, 2021. The process applies an Equal Weight Approach (EWA) to assign equal importance to the 16 normalized variables considered in creating the comprehensive HVI. The overarching goal of this study was to assess heat vulnerability at a local level by offering a detailed analysis of these 16 proposed indicators in an urban setting. The results revealed that the HVI
attained its peak in the year 2021, exhibiting a variable trajectory in its scores, with all
years demonstrating a significant high-risk zone encompassing the regional center.
Findings may enable multiple stakeholders to understand spatial variability of
temperature anomalies at local level and may identify vulnerable populations at risks
Yeast communities of Nova Scotia wine grapes : characterization and implications for winemaking
Get PDF1 online resource (x, 233 pages) : charts (some colour), graphs (some colour)Includes abstract and appendix.Includes bibliographical references (pages 187-224).Wine grapes host a community of yeasts that reflects the unique geography, climate, and
management of a vineyard. After grapes are crushed to produce must, a dynamic succession of yeasts takes place as fermentation unfolds. Initially, many basidiomycete and ascomycete species may be abundant, before one or few fermentative ascomycete yeasts, most often Saccharomyces cerevisiae (Desm.) Meyen 1838, become dominant and complete the fermentation. However, all yeasts contribute to the chemistry of a fermentation via interactions with each other and by using nutrients, secreting enzymes, and producing aromatic compounds. The cumulative result is the distinctive aroma and body of the wine. Despite the importance of yeast communities during fermentation, wine grape yeasts in Nova Scotia have yet to be evaluated. This emerging wine region generates >$245 M/year, supports >1100 jobs, and stimulates tourism. Therefore, the
yeast communities of L’Acadie blanc grapes, a cool-climate hybrid cultivar, were characterized using high throughput sequencing. Considering rising demand for sustainable products, vineyards using organic and conventional cultivation practices were sampled. Yeast communities in musts were composed of predominantly basidiomycete yeasts and were significantly different among vineyard sites and between cultivation practices. One organic vineyard was selected for further analysis using two sequencing platforms (Illumina MiSeq and PacBio) to address biases and evaluate changes following spontaneous fermentation. Both S. cerevisiae and Saccharomyces uvarum Beij. 1898 were found to complete fermentations, but discrepancies in the proportions of these and Hanseniaspora uvarum (Niehaus) Shehata, Mrak and Phaff ex MT Sm 1956 were detected between the sequencing systems. Finally, considering their abundance, a
review of wine grape associated basidiomycete yeasts and their potential applications in
winemaking was conducted, highlighting known effects on wine aroma. Understanding the
complexity of yeast diversity in wine musts and during fermentation can inform both vineyard management and winemaking
Where and when star formation occurs in main sequence galaxies at Cosmic Noon
Get PDF1 online resource (x, 138 pages) : illustrations (some colour), charts (some colour), graphs (some colour)Include abstract and appendices.Includes bibliographical references (pages 76-80).We perform spatially resolved pixel-by-pixel Spectral Energy Distribution (SED) fitting on 166 disky star-forming galaxies between 0.7 < z < 3. Due to the incredible spatial resolution of the Near Infrared Camera on board the James Webb Space Telescope, we are able to probe down to ∼0.75 kpc at z=1. From the 2D property maps made from SED fitting with Dense Basis, we extract property radial profiles such as the stellar mass, star formation rate, and dust. We find that massive galaxies above the star-forming main sequence have dusty, star-forming centers, and galaxies below the star-forming main sequence have centrally-depressed star formation, indicating the inside-out growth of galaxies. Additionally, the star formation rate radial profile is not uniformly smooth, but concentrated in star-forming regions. Overall, our results show when galaxies burst above the main sequence, they add new stars in the disk through spatially inhomogeneous star formation, and in their cores through dusty starbursts