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2021-02-12 Senate Minutes and Agendas
No full textMinutes and agenda for the February 12th, 2021 meeting of Saint Mary's University Senate
Using epiphytic lichens as biomonitors of atmospheric mercury and dust at a historical gold mine tailings site in Nova Scotia, Canada
Get PDF1 online resource (vi, 177 pages) : colour illustrations, colour maps, colour charts, graphsIncludes abstract.Includes bibliographical references (pages 25-36, 119-135, 166-172, 177).Historic gold mining in Nova Scotia, Canada, produced mercury (Hg)-contaminated
tailings from the 1860s to 1940s that were deposited into the environment and
subsequently abandoned upon mine closures. Today, these degraded landscapes are
potential sources of contaminated dust, posing risks to human and ecosystem health. The
primary objective of this thesis was to use epiphytic lichens (Usnea and Platismatia spp.)
as biomonitors of airborne Hg in the Montague Gold District. Spatial distribution patterns
of Hg in lichens showed hotspots near tailings deposits, reflecting greater inputs of Hg
from windblown tailings, volatilization processes, throughfall, and/or stemflow. The Hg
in the lichens was assessed in two ways, including surface-deposited and absorbed Hg
fractions. These results suggested that gaseous Hg from the tailings was a more important
source of the element compared to particulate-bound Hg. These lichens proved to be
effective biomonitoring tools at Montague for assessing Hg pollution and identifying risk
areas
2021-03-19 Senate Minutes and Agendas
No full textMinutes and agenda for the March 19th, 2021 meeting of Saint Mary's University Senate
Examining species coexistence through the functional trait lens
Get PDF1 online resource (292 pages, 3 unnumbered pages) : colour illustrations, colour maps, charts (chiefly colour), graphsIncludes abstract and appendices.Includes bibliographical references (pages 30-41, 47, 110-116, 181-185, 246-250, 276-277, 292).Introduction: I investigate several key knowledge gaps and inconsistencies observed in
coexistence literature, specifically gaps associated with spatial heterogeneity, functional
trait divergence, and the storage effect. For spatial heterogeneity, empirical research has
resulted in all possible heterogeneity-biodiversity patterns, positive, negative, and neutral.
The lack of consistency between studies indicates a need to further explore this topic and
piece together why various patterns can occur. Although trait divergence has been
associated with species coexistence, work is still needed to understand which specific
traits play the greatest role in plant communities, how intraspecific trait variation
influences coexistence, and to incorporate trait data into community and ecosystem
processes. Furthermore, there is a lack of empirical evidence regarding modern
coexistence theory and the storage effect, so research is needed to determine if these
theories hold true in the natural world.
Methods: In order to address questions surrounding coexistence and plant community
assembly, I created the first functional trait database for Nova Scotia, Canada. In total,
this database contains 13,458 trait values from 203 species comprising 130 genera and 53
families (Chapter 1). Using this database, I conducted one observational and three
experimental studies. The observational study relies on six coastal barren vegetation
datasets to determine how spatial heterogeneity and environmental stress influence
biodiversity and plant community assembly in turn coexistence (Chapter 3). I examined
how soil depth heterogeneity and environmental stress influence plant community
assembly over time in an experimental green roof system (Chapter 4). The purpose of the
final two experiments was to address questions regarding coexistence and functional trait
divergence. I created a greenhouse study examining coexistence under a dynamic
watering regime, and a green roof study examining coexistence at low density (Chapter
5).
Main Findings: Environmental stress, rather then spatial heterogeneity, led to an increase
in functional trait diversity. Since species with more divergent traits are less likely to
compete for limiting resources, this finding indicates the presence of a filter, encouraging
coexistence between species that differ in stress tolerant strategies. This finding is further
emphasised when specific functional traits are examined. Specifically, coexistence in
water-limited environments is possible when species differ in plant height and leaf dry
matter content. This dissertation also demonstrates the importance of analysing the
functional diversity of individual traits. This analysis allows researchers to understand
which specific strategies encourage coexistence and co-occurrence
Marine debris on the coast of Southwest Nova Scotia : an analysis
Get PDF1 online resource (36 pages) : colour illustrations, colour mapsIncludes abstract and appendix.Includes bibliographical references (pages 35-36).This thesis analyzes the levels of marine debris on the coastline of Southwest Nova Scotia and draws possible conclusions for the observed degree of pollution. The plentiful stocks of lobster, scallop, herring, and other marine life in the Atlantic waters surrounding Nova Scotia have led to the creation of multiple commercial fisheries in the Atlantic Canadian region; in addition to the Indigenous fishery that has existed predating Canadian federation. This research sought to identify explanatory variables that could be used to explain the variances in debris levels at different beach sites. It was found that factors relating to the commercial fishing industry may not be as relevant to determining the debris levels as one may think
The wave dissipation potential of Spartina alterniflora in the Bay of Fundy
Get PDF1 online resource (58 pages) : colour illustrationsIncludes abstract and appendix.Includes bibliographical references (pages 51-54).The purpose of this research is to determine the wave dissipation potential of salt marsh vegetation in a temperate, hypertidal estuary. The study site is Clifton Marsh, Nova Scotia, in the Bay of Fundy. This site was selected in part because it is monospecific, with Spartina alterniflora. This research will investigate how effective Spartina alterniflora is at attenuating wave energy and the variability in wave height as the vegetation height increases over time. A transect was set up with 4 RBRduet3 T.D|wave16 — temperature and pressure loggers extending from the mudflat to the vegetated section. Data were collected from mid June to early December 2020. For each two-week dataset, the data was sorted to include only that with a depth greater than 0.1 m, and events were selected to have a significant wave height that is greater than 0.05 m. Vegetation surveys were carried out bi weekly to measure the various parameters such as the stem height, stem diameter and the width of the middle top parts of the leaves. The outcomes show that vegetation has an effect on the wave energy and significant wave height and affects the attenuation capacity of salt marshes. This research demonstrates that the presence of vegetation on salt marshes plays an important role in wave dissipation and attenuation. There needs to be a better understanding of vegetated intertidal environments and incoming waves, to achieve sustainable coastal management and planning
Halifax cholera : an anthropological and geographical analysis of an epidemic's social determinants of health
Get PDF1 online resource (vii, 200 pages) : colour illustrations, maps (some colour)Includes abstract and appendices.Includes bibliographical references (pages 159-176).An increased awareness of the social determinants of health and their interdisciplinary applications has led to a wealth of new research in the last two decades. Anthropologists are using these constantly evolving determinants to explore the human dynamics of healthcare as it relates to cultures and communities. Utilization of the social determinants of health helps guide better decision-making when approaching health crises. This in turn, better accommodates cultural perceptions and concerns. Analyzing past epidemics in light of these facets is one way to examine recurring historical themes necessitating attention today. This research covers an historic epidemic through social determinant frameworks for the purpose of highlighting similarities among human reactions during an epidemic. Variables such as immigration, poverty, gender, and spatial distributions are addressed in the investigation of a cholera epidemic in 1834 Halifax. The goal is to tie in a broad historical narrative that depicts a generalized state of healthcare in nineteenth-century Halifax before developing contemporary medical and anthropological frameworks to which it can applied in scrutinizing responsible organizations and institutions, and their community impacts. Quantitative evidence further develops a physical representation of the 1834 landscape to discuss topographical factors potentially contributing to the epidemic's outcome. A final discussion compares the nineteenth-century realities to the contemporary COVID-19 epidemic, contrasting the human approaches taken in managing an outbreak
2021-05-14 Senate Minutes and Agenda
No full textMinutes and agenda for the May 14th, 2021 meeting of Saint Mary's University Senate
Investigating the global drivers of earthworm species diversity on islands
Get PDF1 online resource (37 pages) : illustrationsIncludes abstract and appendices.Includes bibliographical references (pages 32-36).Large gaps exist in knowledge of the global patterns and drivers of biodiversity, particularly in belowground systems and island environments. Earthworms are a key group of soil invertebrates in many systems due to their ability to act as ecosystem engineers, yet our understanding of their distributions globally is limited. To investigate the drivers of earthworm species diversity on islands, I conducted literature searches to obtain lists of earthworm species on 379 islands. Earthworm species records were found for 99 of the searched islands, with many of the islands for which no species records were found comprising entire archipelagos. The relationship between earthworm species richness and each island’s underlying geology, latitude, distance from the mainland, temperature, precipitation, area, and plant species richness were analyzed using a zero-truncated negative binomial regression model. As predicted, earthworm species richness was positively correlated with island area, plant species richness, and mean annual precipitation and negatively correlated with distance from the mainland. Less expected results were a strong correlation between earthworm species richness and oceanic island geology, and temperature and latitude having no effect on earthworm species richness. Species composition on islands was also explored, and the most widespread species across islands was found to be Pontoscolex corethrurus, a dominant invader in the tropics. Overall, it is clear that earthworm species data is severely lacking for a great number of islands, and future research should focus on further sampling of islands chosen by model predictions. In addition, future work should investigate whether drivers differ for the diversity of native versus non-native species of earthworms on islands
Effect of road salt on soil and water properties in Halifax, Nova Scotia
Get PDF1 online resource (46 pages) : illustrations (chiefly colour), colour mapsIncludes abstract and appendix.Includes bibliographical references (pages 41-45).Road salt is a crucial public safety tool to protect people on winter roads, but it disperses from roads and impacts the environment. Increased salinity affects both soil and water systems with adverse effects observed on vegetation, nutrient cycling, and aquatic organisms. Nova Scotia applies the most road salt of all the Canadian provinces per unit area with a total of 230,182 tonnes. I compiled and analyzed water conductivity data for the Halifax Regional Municipality (HRM) from datasets provided by the Department of Fisheries and Oceans and Halifax Water to determine the spatial and temporal trends in conductivity. Conductivity has been increasing in most HRM lakes since at least 1980, but seasonal trends were inconsistent. To better understand salinity of soil and lakes, fieldwork was conducted at five lakes in Dartmouth, Nova Scotia that represented sites exposed to or protected from road salt. At each lake, we sampled water and soil on a side that was closer to roads/road salt application, and on another side further away. Statistical analysis showed no significant effect of proximity to road salt application on water conductivity (P = 0.834). There was a significant difference between protected and exposed sites (P = 0.0187). Soil electrical conductivity was also measured on both sides of the lakes at distances of 0, 10, and 20 m from the lake before (fall) and after (winter) road salt application. Soil conductivity was significantly higher at 0 m (compared to 10 m, P = 0.020, and compared to 20 m, P < 0.001) and before road salt application (P = 0.014). There was no significant effect of protection (P = 0.079) or proximity to road salt application (P = 0.184) on soil conductivity. Based on these results, I concluded that road salt is negatively impacting many lakes in the HRM