Amanda Giang

Marine shipping, responsible for about 80% of global trade by volume, also contributes 3% of global greenhouse gas (GHG) emissions. In line with the International Maritime Organization’s (IMO) net-zero strategy, Canada has set ambitious GHG reduction targets for its marine sector. Given the sector's reliance on fossil fuels and the urgent need for decarbonization, marine operators are particularly interested in near-term alternatives like biodiesel and renewable diesel for achieving interim targets by 2030. However, significant gaps remain in understanding the supply feasibility of these fuels in the Canadian context, including feedstock availability, market fluctuations, and biofuel policies. This research evaluates biodiesel and renewable diesel supply chain vulnerabilities in Canada to support marine operators’ decision-making from a supply feasibility perspective.This thesis addresses these gaps by developing a comprehensive vulnerability assessment framework for biodiesel and renewable diesel supply chains, combining a suite of systems analysis methods. Inspired by the Drivers, Pressures, States, Impacts, Response (DPSIR) framework, this study identifies and defines key pressures and state indicators for both alternatives. Causal loop diagrams (CLDs) are developed to map how these pressures can influence the reliability and consistency of fuel supply through the measurement of state indicators. Strategy mapping analysis, using graph theory and complex network theory, further highlights the interconnection of international and domestic supply chains and the vulnerable supply chain processes, such as feedstock supply and end-user demand.To ground the conceptual assessment framework in real-world application, this thesis explores four regional case studies of Canadian biodiesel and renewable diesel supply chains, assessing the unique regional supply challenges faced by marine operators. For instance, in the Arctic, extreme cold can cause biodiesel to gel, making renewable diesel a more reliable, though costly, alternative for marine operators. In the Atlantic, market fluctuations driven by competitive demand from other sectors and global influences raise concerns about domestic supply availability for government operators and create significant cost uncertainties for commercial operators. These case studies clarify how these factors shape regional fuel preferences, inform strategies for adopting alternative fuels, and strengthen consistent and reliable fuel supply in Canada.

View record

The United Nations has recognized that everyone has the right to a clean, healthy, and sustainable environment; however, the uneven spatial distribution of demographics and environmental quality can result in disproportionate exposure to environmental risks or lack of access to benefits for disadvantaged groups, leading to distributive environmental injustice. Additionally, the changing climate and environment may exacerbate injustice over time, resulting in vulnerable groups facing more risks. Given the unclear spatial distributions of multidimensional environmental quality and environmental justice over time in Metro Vancouver, this study aims to: 1) characterize the patterns of multi-dimensional environmental quality and related injustice that consider interactions, synergies, and trade-offs between multiple environmental factors and 2) investigate the changes in these patterns over time between 2006 and 2016. This study applies two methods to assess multi-dimensional environmental quality: one aims to represent variations in two dimensions of environmental quality, and the other constructs multiple environmental indices to assess the composite environmental quality. Environmental injustice is characterized using regression models and group differences, which aim to reveal the limited access to favourable environments or increased exposure to unfavourable environments for disadvantaged populations. This thesis generated environmental quality maps at dissemination area (DA) resolution for 2006 and 2016, then explored spatial distributional environmental injustice patterns in Metro Vancouver and their changes over time. Across different metrics of environmental quality, environmental injustice patterns are changing through time and across space; these changing patterns are driven by different aspects of environmental quality. Although environmental quality is generally higher in 2016, it is not evenly distributed. More materially and socially deprived populations lived in areas with fewer environmental benefits and/or more burdens. Injustice is also not improving for all groups: for instance, South Asian residents of the region experienced more injustice across a number of environmental quality variables in 2016 compared to 2006. Based on the local-level characterization of demographics and environmental quality, this study identifies specific DAs with high percentages of disadvantaged populations, unfavourable environmental quality, and high levels of injustice, which could suggest priorities for interventions.

View record

Mexico is one of the main centres of origin of agriculture and domestication of a diversity of plant species that are fundamental for food security. Given the importance of conserving traditional crops, research in the country has mainly focused on crop diversity at the genetic level of these few crops. However, thanks to the country's geographic location, the biocultural heterogeneity of the landscape, and openness to international markets, today, Mexico grows more than 200 food crop species. This study used statistical analysis of Mexican agricultural census data to evaluate changes in Crop Species Diversity (CSD) from 1980 to 2016 for five agroecological regions of Mexico. CSD temporal trends are described through simple linear models, segmented regressions, and a Non-metric Multidimensional Scaling (NMDS) technique. Overall, we found that while diversity has been increasing in 4 out of 5 regions, regions are becoming more similar. This homogenization of the Mexican agricultural sector could therefore have major social, economic and environmental implications.

View record

While mercury occurs naturally in the environment, human activity has significantly disturbed its biogeochemical cycle. Inorganic mercury entering aquatic systems can be transformed into methylmercury, a strong neurotoxicant that builds up in organisms and affects animal and public health. In the Arctic, top predators such as beluga whales—an ecologically and culturally significant species for many Inuit communities—can contain very high concentrations of methylmercury. Historical mercury concentrations in beluga in the western Canadian Arctic’s Beaufort Sea cannot be explained by mercury emissions trends alone, but they could potentially be driven by other factors in the rapidly changing Arctic, including rising temperatures, changes in food web structure, and melting sea ice and permafrost. This study explores the main drivers of mercury bioaccumulation in various species in the Beaufort Sea beluga food web using an ecosystem modelling software called Ecopath with Ecosim (EwE) and scenarios of environmental change informed by both Western science and Inuvialuit Knowledge. Through literature review, interviews with scientists, and engagement with Inuvialuit knowledge holders, I find that many environmental changes in the region have been climate-driven and have the potential to affect mercury cycling via three broad mechanisms: Mercury flows into the Beaufort Sea, mercury methylation, and food web effects. Comparing the effect of historical sea ice, sea surface temperature, and freshwater discharge time-series, exploratory ecosystem modelling highlighted that historical trends in beluga methylmercury were best explained by productivity-driven changes rather than mercury inputs, and that all three environmental drivers could help explain the decrease in mercury concentrations in beluga after the mid-1990s. This research identifies drivers of mercury variability, highlights knowledge gaps in both the Beaufort Sea ecosystem and mercury research more broadly, and makes space for different ways of knowing. Moving forward, methods employed here, such as fuzzy cognitive mapping and ecosystem modelling, could help us make fisheries and pollution management decisions and explore scenarios of change in an uncertain future.

View record

Ambient air pollution is one of the leading health and environmental concerns worldwide, including in Canada. To manage air pollution and its impacts, Canadian governments create and enforce various laws and regulations. Most areas in Canada usually experience good air quality, but some communities are disproportionately exposed to harmful air pollution, constituting an environmental injustice. While these concepts of ambient air pollution, environmental enforcement, and environmental justice have each been studied either in isolation or in pairs in Canada, no research has examined the three together. In particular, patterns of enforcement of air pollution laws are understudied, and it is not known whether enforcement varies according to the characteristics of different communities. This study seeks to address these gaps and investigate the nexus of air pollution, environmental law enforcement, and environmental justice in Canada by examining the following research questions: RQ1: How do enforcement data availability and quality vary between and within provinces? RQ2: What are the demonstrated models of enforcement? How do they vary across jurisdictions, time, or other factors? RQ3: What types of violations or offenders appear to be prioritized for enforcement action in Canada? RQ4: How are the sociodemographic characteristics of areas in which enforcement actions occur different from the provincial averages of those characteristics? I created a dataset of enforcement actions against air pollution law violations using data gathered from eight provinces and the federal government, which I then analyzed using descriptive statistics and geospatial techniques. I developed a rubric to evaluate and compare jurisdictions’ data availabilities and qualities and found that all were generally poor and incomplete, which violates the community right to know and the individual right to information. Through descriptive statistics, I observed that across provincial and federal jurisdictions, regulators appear to employ a cooperative approach to enforcement. Environmental priorities and enforcement outcomes do not seem to align on several levels, especially regarding large emitters and repeat offenders of air pollution laws. Finally, geospatial analyses revealed some environmental injustice patterns related to the location of enforcement actions. I offer several recommendations to improve enforcement strategies within and beyond existing policy systems.

View record

Environmental Impact Assessment (EIA) faces significant criticism with respect to its scientific approach and oft disjointed legislation. Although appeals for more rigorous science and legally binding obligations for decision-makers are warranted, it is also crucial to acknowledge that regulatory science is situated in specific social, institutional, and political contexts. Therefore, in addition to science and legislation, relevant social processes influence the way in which knowledge is gathered, legitimized, and interpreted, thus affecting regulatory decisions. However, there remains an important empirical gap in understanding how these processes affect knowledge construction in an EIA context. In Chapter 2 of this thesis, I use Situated Analysis to explore the knowledge politics around methylmercury contamination that emerged throughout the EIA of the controversial Muskrat Falls portion of the Lower Churchill Hydroelectric Generation Project, situated in Labrador, Canada. I focus on debates about knowledge related to downstream methylmercury impacts, human health, and mitigation measures to reduce the production of and exposure to methylmercury. I find that there are distinct knowledge orders that interact and collide, generating knowledge conflicts about framing of the policy problem, norms of knowledge construction, and reasoning about the policy problem. Using illustrative examples from the Muskrat Falls case study, this work highlights and categorizes knowledge conflicts that may emerge over the course of a controversial environmental regulatory decision. I also argue that power intersects with EIA in a way that privileges some knowledge orders over others. Privileged knowledge orders are often aligned with particular conceptualizations of human health, the environment, and natural resources. In Chapter 3, I propose an educational activity based on the Muskrat Falls case study that enables post-secondary students to explore how Structured Decision-Making (SDM), a framework for environmental policy decisions that emphasizes objectives and values, may address knowledge conflicts and competing knowledge orders in an EIA context. More broadly, my findings echo calls for a more pluralistic approach to EIA that acknowledges existing power structures in the regulatory context. I also discuss the implications of these findings for the next iterations of EIA legislation and policy.

View record