Geography and Environmental Management

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This is the collection for the University of Waterloo's Department of Geography and Environmental Management.

Research outputs are organized by type (eg. Master Thesis, Article, Conference Paper).

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Assessment of the Proposed Policies for a Carbon Capture and Storage Regulatory Framework in Ontario
(University of Waterloo, 2025-02-21) Kim, Duckhoon; Schweizer, Vanessa
Since 2022, Ontario has been investigating the possibility of developing a Carbon Capture and Storage (CCS) framework as they aim to reduce carbon emissions and align with the federal government’s goals of net-zero emissions by 2050. This CCS regulatory framework should focus on hard-to-abate sectors where alternative renewable energy technologies are in their early stages, or they are difficult to be transitioned. However, within the research field of CCS in Ontario from a policy perspective, there are minimal journal articles and grey-literature documents that discuss this topic. Therefore, the purpose of this thesis is to understand and analyze Ontario’s proposal of their regulatory framework for CCS and to give recommendations to the CCS framework by comparing it against the information gathered from other jurisdictions (Alberta, Saskatchewan, the United States, Europe and Australia). Key research questions are 1. How can the knowledge gained from other regions regarding CCS help Ontario's hard-to-abate sectors to understand approvals, licensing, and liability? 2. What are some other necessary policies that Ontario would need to expand upon and potentially adopt from various jurisdictions? And 3. How did companies and governments in other jurisdictions communicate to the public about the need for this technology? The thesis first developed a literature review to compare and contrast policies from other jurisdictions by researching and synthesizing various peer-reviewed journal articles and grey literature. Then, a semi-structured interview was needed to explore any unique perspectives from interviewees with expertise in CCS, and also to understand whether the results aligned with the information from the literature review. Following the interviews, the analysis of the results were accomplished by using ‘codes’ and ‘themes’, which allows for a simplified understanding of which information is unique. As a result, there were unique findings from the interviews such as ensuring proper industries are utilizing CCS, explaining the purpose of CCS, ensuring that the regulatory framework for CCS is properly developed, and the potential for CCS to utilize a carbon market through an Emissions Trading System (ETS). In November 2024, Ontario introduced Bill 228, which contains an Act called the Geologic Carbon Storage Act, 2024. This Act contains the key core components of the regulatory framework, such as ownership, liabilities, and approvals and assessments. As a result, a description and analysis of this Act was undertaken to understand how it compares against my research findings. In conclusion, to answer the first research question, the findings resulted in requiring Ontario to vest in the pore space, implement a unitization statue, implement a transfer of liabilities once certain pre-conditions are met and a post-stewardship fund to cover liability costs. As for the second research question, the other necessary policies include expanding upon environmental assessments methods, using a systems analysis approach to understand the outcomes of developing CCS, incorporating CCS into carbon pricing schemes, and Ontario’s plans on how they should utilize their CCS. The findings for the final research question recommend that the Ontario government and companies recognize the social demographic backgrounds of Ontario; ensure that Ontario is integrating and engaging with communities closely; explaining the downsides of not developing a CCS project; and respecting a community’s decision if they do not wish to engage with the project. Bill 228 is consistent with these findings, namely the inclusion of a liability transfer; a stewardship fund to cover the liabilities for the Crown; unitization of pore spaces; risk management; monitoring, measurement and verification (MMV); emergency response; and various approvals and assessments. However, the ownership of pore spaces deviates from these findings, as Ontario vests pore ownership to the surface owners but still allows the Crown to vest in the pore space when required.
Imagining Shared Food Futures: honouring Canada's obligations towards Anishinaabek foodways
(University of Waterloo, 2025-02-20) Koberinski, Jodi; Scott, Steffanie
Sustainability scholars characterize climate breakdown and biodiversity loss as converging crises tied directly to settler colonial ‘resource management’ regimes. Canada gestures toward mitigating these crises by ‘including’ Indigenous knowledges in environmental impact assessments and policy. Canada prioritizes commodity market profitability over mitigating these crises by excluding Indigenous knowledges in resource management decisions when acting on that knowledge would disrupt industry-favoured practices. One such practice is glyphosate use in forest ‘management.’ Glyphosate is a broad-spectrum agricultural herbicide repurposed to ‘manage’ regrowth after clearcutting forests. Banned by Quebec in 2001, Ontario embraced this practice. In 2013, Anishinaabek Elders along the north shore of the Great Lakes formed the Traditional Ecological Knowledge Elders to campaign for a moratorium on glyphosate use, which is counter to Anishinaabek environmental governance. Proponents claim herbicide use speeds stand regeneration, yet that regeneration converts food-bearing forests to pine plantations. Ontario legislators are not seeing the forest for the trees. This dissertation contributes to radical food geographies scholarship by characterizing the cumulative impacts of forestry policies on Indigenous foodways. Foodways include economic, material, linguistic, spiritual, intergenerational, scientific, ceremonial, and social dimensions of a culture’s food governance. This study concludes that efforts to imagine shared food futures in Canada’s settler colonial context require reframing ‘renewable’ resource extraction as Indigenous foodways disruption. Applying case study and participatory action research methods, I offer three manuscripts that together characterize the limitations of settler colonial knowledge in imagining shared food futures that meet settler treaty obligations. These three studies conclude that converting Anishinaabek food-bearing forests to pine plantations undermines the conditions required for Canada to meet treaty obligations to protect Anishinaabek foodways. In the first manuscript, I adapt Vivero Pol’s multi-governance framework to Canada’s settler colonial context to analyze customary and contemporary Indigenous food initiatives through a food commons lens. This study reveals the limitations of settler colonial frameworks for imagining shared food futures. The second manuscript seeks to overcome these limitations by centring an Anishinaabek research paradigm in collaboration with Traditional Ecological Knowledge Elders of the North Shore of Lake Huron. Our case study examining the cumulative impacts of changes to forestry legislation on Anishinaabek foodways centres TEK Elders’ efforts to stop glyphosate use in forestry. Reflecting on Ontario’s Bill 197, we characterize the limitations of settler colonial knowledge systems for understanding the impacts of forest ‘management’ decisions on settler treaty obligations. To better understand the limitations raised in the first two manuscripts, I apply participatory action research methods in the third manuscript to analyze transcripts from the Canadian Society of Ecological Economics’ bi-annual conferences I co-organized between 2019 and 2021. I ask what Indigenous knowledge holders have to say about the repackaging of Indigenous concepts by sustainability researchers within colonial knowledge systems. Despite gestures towards ‘inclusion’ of Indigenous knowledge, settler colonial frameworks depoliticize Indigenous resistance and resurgence, often reinforcing colonial narratives of land cessation and dispossession. Without addressing the underlying settler colonial assumptions and structures, sustainability scholars and settler governments relying on their research risk replicating the violence inherent in food policy frameworks built on settler supremacy. Collectively, these manuscripts identify actions settler colonial scholars have the responsibility to take up, beginning with transforming settler colonial narratives.
Long-term biophysical conditions and carbon dynamics of a temperate swamp in Southern Ontario, Canada
(University of Waterloo, 2025-02-13) Afolabi, Oluwabamise Lanre; Strack, Maria
In Canada, wetlands cover a land area of 1.5  106 km2 and store ~129 Pg C. However, the carbon (C) cycling of swamps has been understudied even though they store substantial quantity of C in their biomass and can also accumulate peat. In particular, southern Ontario swamps are estimated to hold ~1.1 Pg C under distinct hydroclimatic conditions. Previous studies on temperate swamp C fluxes were mostly based on short-term (<5 years) field measurements that limit our understanding of the multi-decadal dynamics that exist between this ecosystem’s C flux and biophysical conditions. To elucidate the long-term interactions and feedbacks that are important to temperate swamp C dynamics, a process-based model (CoupModel) was used to simulate plant processes, energy, water and C fluxes in one of the most well-preserved swamps in southern Ontario over 78-year period (1983–2060). CoupModel reasonably simulated the C flux and controlling variables when validated with compiled historic field measurements (1983–2023) with coefficient of determination (R2) values of 0.60, 0.95 & 0.61 for soil respiration, surface soil temperature (0–5 cm) and water table level (WTL). Systematic calibration of the initialized model for Beverly Swamp with the Generalized Likelihood Uncertainty Estimation (GLUE) approach moderately reduced the uncertainty associated with modelling processes and assisted in identifying the important parameters that greatly influence temperate swamp C flux simulations. Plant-related processes and hydrological variables exerted the strongest control on the simulation of carbon dioxide (CO2) efflux through soil respiration. The forcing of the GLUE calibrated CoupModel with an ensemble of climate projections downscaled from earth system models (ESMs) under shared socio-economic pathway (SSP5) by mid-century (2060) produced a decline in the swamp’s C uptake capacity as net ecosystem exchange (NEE) of CO2. Relative to the reference period of 1983–2002, the projected increase in mean air temperature (4.3 ± 0.8 oC) and precipitation (0.2 ± 0.1 mm) by 2050s triggered increase in 5 cm deep soil temperature, vapor pressure deficit, and evapotranspiration at Beverly Swamp. These changes to the swamp’s thermal and hydrological conditions dropped its WTL and VMC. Consequently, drier and warmer conditions raised the swamp’s CO2 efflux through ecosystem respiration, while its GPP moderately increased. These bidirectional feedbacks contributed to a reduction in the swamp’s net C uptake (NEE) by the 2050s but it mostly still maintained its net C sink role. While uncertainty in future climate projections and model fit limit our confidence in the precise estimate of future carbon exchange, it was clear that seasonal timing of warming and precipitation played an important role in the swamp response, with coincident declines in precipitation and warming temperatures in summer that caused water stress for plants. Results from this long-term study will help improve our understanding of the important ecohydrological interactions and feedbacks that drive the C cycle of temperate swamps, and their contributions to regional terrestrial C and water cycles. This will help inform decision making on the role of swamp peatlands as nature-based climate solutions through improved understanding of their net C exchange with the atmosphere.
Investigating the Dynamics of Meandering River Cutoffs: Relationships with Discharge, Land Cover and Spatial Clustering
(University of Waterloo, 2025-02-04) Sun, Letong; Robinson, Derek; Lewis, Quinn
As climate change has become one of the major concerns across the globe, investigating the dynamics of meandering river evolution is substantial for urban river management and flood mitigation plans. In recent years, the study on river cutoff has been given lots of attention, as its occurrences and impacts were unpredictable and catastrophic. This study investigates its relationship with high-flow events, land cover and spatial clustering through flood frequency analysis, cutoff ratio criterion and spatial cluster analysis. 1,186 river cutoffs across the United States are located and identified based on Google Earth Imagery. 12 highly sinuous rivers with high cutoff occurrences are then selected and processed through R Studio and ArcGIS. The results show no strong correlation between high-flow events and cutoff occurrence across the study areas. Discharges with an average of approximately eleven-year return period are associated with cutoff occurrences. With the installation of the cutoff ratio in the dataset, it is found that chute cutoffs with higher CRm_m values are likely to occur on land cover types with lower erosion resistance. Neck cutoffs are usually found in floodplains less susceptible to erosion, particularly in undisturbed vegetated areas. Spatial cluster analysis shows that neck cutoffs are significantly clustered at all scales, whereas chute cutoffs exhibit relatively lower clustering tendencies and tend to be more event-driven. Minimizing the random disturbances in the analysis, this study collectively validates the non-random behaviour of cutoff occurrences, which further calls attention to the importance and viability of assessing and predicting cutoff evolution in urban planning and flood management.
Testing the application of novel technology for monitoring grape vine health and berry maturity using transmitted visible and near infrared light
(University of Waterloo, 2025-01-29) Riddoch, Bronwyn; Petrone, Richard
Climate change is impacting wine-growing regions globally, with varying effects on vineyards. While some regions may benefit from warmer temperatures, others may face detrimental consequences, especially with the predicted increase in extreme weather events or less than optimal conditions. Precision viticulture uses remote and proximal sensing technologies to monitor these changes and adapt vineyards by providing insights into vine health and grape maturity. This information can be used to determine when intervention is needed in vineyards to maintain grape quality. However, existing precision viticulture methods are limited, such as the inability to provide continuous, real-time data and the utilization of reflected light, which can lead to inaccurate measurements. Current research has not yet investigated the potential of using transmitted light for monitoring vine health and grape maturity, a method that could provide more accurate insights. This thesis seeks to fill this gap by evaluating the feasibility of applying a novel system, TreeTalker-Wine© (TTW), to continuously monitor grapevine health and maturity through transmitted light in commercial vineyards. To test the application of TTWs for monitoring vine health, the sensors were deployed under the canopy of Cabernet Franc in two commercial vineyards in Niagara, Ontario, Canada. Spectral data collected by the TTWs was used to calculate the daily Normalized Difference Vegetation Index (NDVIT) based on transmitted light. The resulting NDVIT values were consistent with expected ranges and aligned with viticultural management practices and weather events. To assess the potential of TTWs for monitoring grape maturity, partial least squares (PLS) models were developed for Cabernet Franc, Chardonnay, and Riesling varieties using spectral data from the grape clusters, along with air temperature and Total Soluble Solids (TSS) content. Grape clusters were collected bi-weekly from a third vineyard in Niagara, Ontario, Canada, starting at the pea-size stage and continuing through veraison. After veraison, sampling frequency increased to weekly until harvest. After each collection day, the fruit was transported to a laboratory with a plant growth chamber designed to replicate the vineyard’s environmental conditions. Grape clusters were suspended over the TTWs in the plant growth chamber to collect spectral signatures of the fruit before the entire cluster was juiced to determine TSS content. The results of the PLS models suggest that TTWs are able to determine TSS content from the spectral signatures of the grape clusters, however unique models are required for each grape variety. These findings indicate that TTWs offer a promising approach to precision viticulture. Future research is needed to assess a broader range of grape varieties to better understand the relationship between NDVIT and vine health, as well as to refine the TSS prediction models. This will enable further exploration of the potential of transmitted light in monitoring grapevine health and maturity, supporting more accurate and timely viticulture practices in changing climate.
From disaster recovery to whole-of-society resilience: The impact of the 2021 British Columbia atmospheric rivers event on flood risk management policy and governance
(University of Waterloo, 2025-01-23) Watterodt, Felicia; Doberstein, Brent
Flooding poses significant risks to the safety, well-being, and long-term security of many Canadian communities. In recent years, extreme weather events, as a result of a changing climate, have cost Canadians billions in insured and uninsured losses annually, and such losses do not encapsulate the various social, ecological, and health impacts that are difficult to quantify. In addition to climate change, misaligned land-use planning, intensified development in floodprone areas, fragmented risk governance, gaps in funding and policy, and an over-reliance on protective structures continue to place many Canadians in harm’s way, while creating barriers for proactive adaptations at the watershed scale. Major disasters, like the 2021 atmospheric rivers floods in British Columbia, underscore the need for transformative flood risk management [FRM] policy and governance by highlighting the systemic drivers of flood risk, namely a FRM system that was never designed to withstand the dynamic realities of the present day. Such focusing events—relatively rare, sudden, and impactful events like disasters—are often critical in generating significant public interest around a focal issue, garnering political will to advance policy agendas, and enabling governance actors to advocate for policy reform. In the post-disaster landscape, coalitions of policy actors can seek to leverage these emergent ‘windows of opportunity’ to advance a paradigm shift in how various public issues, like disaster risk reduction and climate change adaptation, are understood and managed, who is involved in decision-making processes, and what solutions are considered socially-acceptable and politically-feasible. Actors are most likely to be successful in advancing agenda items if enabled by the institutional environments that policy processes are embedded within, and if there is an existing foundation of collaboration among others within the broader policy community. This research, utilizing a case study of a major Canadian flood disaster, evaluates the ways in which policy champions, advocacy coalitions, and institutional actors have sought to leverage existing relationships, prior learnings, and post-disaster momentum to advance shifts in FRM policy and governance at the local, regional, and provincial scales. Semi-structured key informant interviews provide insights into how the disaster manifested as a focusing event, what enabling conditions contributed to the creation of a window of opportunity for policy change, and how recent shifts in British Columbia’s flood governance and policy regimes have been shaped by longer-term institutional developments and interjurisdictional partnerships. This research illustrates the transformational nature of adaptive learning and multi-scalar governance, and is intended to assist FRM decision-makers, policymakers, and practitioners in advancing resilience.
Uncovering the understudied role of microtopography and ground cover on evapotranspiration partitioning in high-elevation wetlands in the Canadian Rocky Mountains
(University of Waterloo, 2025-01-21) Wang, Yi; Petrone, Richard
A warming climate is projected to alter hydrological regimes in high mountain regions, including the Canadian Rocky Mountains. Rivers originating from the eastern slopes of the Canadian Rocky Mountains provide up to 90% of streamflow to downstream users in the Saskatchewan River Basin and have shown significant declines in summer discharge. In mid to late summer, as streamflow gradually decreases while water demand for agriculture, industry, and domestic use remains high, this reduction in streamflow imposes considerable stress on water use for various needs in downstream areas. Wetlands buffer excess water during floods and alleviate water shortage during droughts, making them crucial for sustainable water resource management. With glacial recession, wetlands may become more widespread; however, their hydrological roles are uncertain. Evapotranspiration (ET) represents the total water loss from the wetland surface to the atmosphere through both evaporation and transpiration, which is typically the largest component of the wetland hydrological cycle. Accurately quantifying ET is essential for understanding ecosystem water use patterns, estimating water budgets, and designing sustainable water resource management strategies. The environmental controls of ET in high-elevation wetlands are currently not well understood. The effects of land surface features such as microtopography, bryophytes, and litter covers, commonly found in these ecosystems, on ground surface evaporation—a component of ET—remain insufficiently explored. This thesis investigated these impacts across three typical high-elevation wetland types on the eastern slope of the Canadian Rocky Mountains: a montane fen (Sibbald), a sub-alpine marsh (Burstall) and a sub-alpine wet meadow (Bonsai). Field measurements of controlled evaporation experiments were conducted over various soil substrates and ground cover types, with and without an overstory willow canopy, during July and August 2021. The results showed that microforms and the overstory willow canopy did not exhibit statistically significant direct impacts on ground surface evaporation. Instead, their influences were indirect, affecting soil temperature profiles and below canopy microclimates, which in turn influenced ground surface evaporation. Conversely, ground covers, including litter and bryophytes, significantly impacted on ground surface evaporation, with effects varying by site and involving complex interactions with evaporative demand and water availability. In high-elevation ecosystems, the lack of adequate measurements of energy and water balance components, primarily due to high instrumentation costs and accessibility challenges, hampers understanding of their hydrological processes. While modelling approaches may be convenient and enable the exploration of temporal variability of energy and water fluxes, they require accurate parameterization, and model validation is often unavailable. It remains uncertain whether and how microtopography and ground covers should be integrated into modelling frameworks to enhance the representation of water and energy fluxes of high-elevation wetland ecosystems. This thesis found that the effects of microtopography on ground surface evaporation were satisfactorily modelled by the Penman–Monteith model and a more complex bryophyte layer model in the Atmosphere-Plant Exchange Simulator (APES), based on soil temperature measured in these microtopographical features. The effects of ground covers and overstory canopy on ground surface evaporation were successfully modelled based on the modelling framework of soil evaporative efficiency (SEE) which is the ratio of actual to potential ground surface evaporation. Given that high-elevation ecosystems generally lack sufficient ground measurements for model calibration and validation, this thesis established a simple approach for modelling the SEE of vegetated surfaces over a range of soil substrates and ground cover types, based on the mass fractions of bryophytes and litter. Additionally, a correction method was developed to account for the effects of an overstory willow canopy on SEE. This novel approach is less parameter-intensive compared to conventional methods and potentially widely applicable beyond the three study sites. Both the field experiments and the proposed SEE model formulation illustrate that ground covers significantly influence ground surface evaporation, a key component of ET. This highlights the importance of further studying the effects of ground covers on both ET and its partitioning into evaporation and transpiration at the ecosystem scale. Since field measurements alone are insufficient to fully capture the daily dynamics of ET partitioning, modeling techniques were applied to achieve this goal. To quantify the relative contribution of ground surface evaporation (E) and vascular plant transpiration (T) to wetland ET at a daily scale, part of the newly developed SEE approach, which estimates the surface resistance of bryophytes and litter covered wetland ground surfaces, was incorporated into the widely used Shuttleworth–Wallace (S-W) model. Based on this model, the relative contributions of E and T fluctuated daily in response to meteorological conditions and soil moisture content during the study period. The average daily T/ET ratios for Sibbald, Burstall, and Bonsai were 0.86, 0.46, and 0.61, respectively. When excluding rainy days, the average T/ET ratios were 0.86 for Sibbald, 0.50 for Burstall, and 0.60 for Bonsai. The modified S-W model performed with satisfactory accuracy when compared to field measurements. Assuming that the modified S-W model accurately captures the fundamental mechanisms driving wetland ET partitioning, this model was employed to simulate daily ET partitioning with varying ground cover fractions to investigate the effects of ground covers on ET and T/ET. The results indicated that bryophytes and litter had a minor impact on the magnitude of T/ET, though their influence may be more pronounced in wetlands with an elevated water table. A literature synthesis was further presented to reveal that wetland ET partitioning is strongly controlled by leaf area index (LAI) and moderated by water table depth. However, due to the absence of surface runoff measurements and continuous groundwater level monitoring, the water balance could not be estimated for each study site. Future research should explore potential interaction effects of water table level with microforms and ground covers as well as possible seasonal variations in their effects on wetland ET. Overall, this research reduced uncertainties associated with land surface heterogeneity in estimating ET and its partitioning in high-elevation wetlands, offered new perspectives for developing ET models, and facilitated the evaluation of ecosystem services and hydrological processes in these ecosystems.
Application of GNSS Reflectometry for the Monitoring of Lake Ice Cover
(University of Waterloo, 2025-01-20) Ghiasi, Yusof; Duguay, Claude
Lakes cover vast expanses of land in many regions of the Northern Hemisphere. Their presence has been shown to have a significant impact on local weather and climate. The seasonal presence of ice cover affects the transfer of energy and heat between lakes and the overlaying atmosphere, as well as various socio-economic activities, including transportation, recreation, and cultural practices. However, climate change is rapidly altering lake ice cover and its phenology and ice thickness with meaningful implications for both human activities and the ecosystems they support. Monitoring the seasonal variability and changes in lake ice cover and thickness is crucial for understanding the impacts of climate change; however, traditional in-situ observations have declined over the last few decades, creating a need for innovative remote sensing approaches. Global Navigation Satellite System Reflectometry (GNSS-R) offers a novel, cost-effective method for monitoring lake ice dynamics. Unlike traditional remote sensing techniques, GNSS-R utilizes existing satellite signals (known as signals of opportunity), providing high temporal and spatial resolution data that can be used to detect and analyze lake ice conditions. This thesis investigates the application of GNSS-R for lake ice remote sensing, focusing on the signals' sensitivity to different phases of lake ice and its potential ice detection and the monitoring of lake ice phenology. The thesis begins with an exploration of the fundamentals of GNSS-R and its relevance to lake ice remote sensing. Through understanding the scattering mechanisms involved when GNSS signals interact with lake ice, this research establishes a theoretical framework that supports the subsequent experimental analyses. The research then evaluates the sensitivity of GNSS-R signals, particularly the Signal-to-Noise Ratio (SNR), to various lake ice conditions. Using data from the Cyclone Global Navigation Satellite System (CYGNSS) mission over Qinghai Lake, the thesis examines how SNR values change in response to freeze-up, ice cover, spring melt onset, and breakup. The results demonstrate that GNSS-R can effectively monitor lake ice dynamics with high temporal resolution, making it a valuable tool for tracking the seasonal evolution, inter-annual variability and changes in ice cover. Further investigation is conducted on the potential of hybrid compact polarimetry in GNSS-R for analyzing lake ice cover properties. Data from the Soil Moisture Active Passive Reflectometry (SMAP-R) mission acquired over large Canadian lakes are analyzed to assess the sensitivity of polarimetric GNSS-R signals to ice cover conditions. The study finds that hybrid compact polarimetry enhances the interpretation of GNSS-R data, particularly in distinguishing between different ice and water conditions. In addition, the use of machine learning, specifically random forest, combining several polarimetric parameters, improves the accuracy of lake ice phenology detection compared to using each parameter alone. To deepen our understanding of how lake ice modifies the reflectivity of GNSS signals, a multi-layer scattering regime model is developed and validated against CYGNSS data. The model simulates the interaction of GNSS signals with various lake ice layers and the underlying water interface, providing insights into the complex scattering processes that influence GNSS-R measurements. The successful validation of the model demonstrates its utility for improving the accuracy of lake ice phenology analysis and offers a robust tool for broader cryospheric applications. This thesis contributes to the field of remote sensing by demonstrating the effectiveness of GNSS-R in monitoring lake ice and advancing the understanding of GNSS signal interactions with ice-covered surfaces. The findings highlight the potential of GNSS-R as a low-cost, high-resolution tool for tracking lake ice dynamics, with implications for climate monitoring, weather forecasting and environmental management.
Transition to electric vehicles: the importance of macro and micro influences on spatial and temporal patterns
(University of Waterloo, 2025-01-20) Chen, Yixin; Andrey, Jean
The climate crisis is widely recognized as being caused by unsustainable consumption and production patterns across various social domains, which motivates the demand for an acceleration of transformative changes with the goal of sustainability. Socio-technical transitions, offers a path forward. That said, a core impediment is an incomplete understanding of how multiple elements co-evolve in different contexts. Various lenses, theories, and approaches have been used to analyse and explain technology adoption and diffusion in societies; these can be characterised as macro-level (‘structure’) or micro-level (‘agency’), but to date the linkages between them in understanding transition processes have been under-explored. This gap provides a research opportunity for the thesis to question in what ways can macro-level and micro-level lenses explain the spatial and temporal patterns of the transition process to electric vehicles (EVs), an example of a transition for the decarbonization of mobility. With specific reference to Canada, the thesis aims to illuminate the multi-dimensionality and complexity of how the transition to EVs is unfolding, using a quantitative approach including indicator development and statistical modelling. The thesis adopts two complementary components. One aims to describe and explain the spatial and temporal patterns of transition to EVs at a national level between 2017 and 2022 by drawing upon the ‘geography of transitions’ literature and modelling secondary data of new EV registration by seven provinces in Canada by quarter. The other component seeks to understand and assess changes of consumers’ likelihood and perceptions to purchase EVs in one municipality, Waterloo Region, between 2020 and 2023, framed by ‘diffusion of innovation’ concepts and based on primary data from two public surveys. In both analyses, robust models highlighted the importance of various factors in leading to EV adoption and diffusion. These macro-level and micro-level analyses both depict the transition to EVs in Canada as proceeding at a slow pace, with variations across space and time and society. The micro-level analysis further suggests that the transition is hampered by the resistance of nearly half of the population in the local context. Longitudinal dynamics of individual consumers’ perceptions of EVs and differences and changes at the landscape level mutually reinforce each other. For example, consumers’ recognition of EVs’ environmental benefits have the most substantial influence on people’s interest in EVs, which also echoes the significant role of societal environmentalism, as one of the representations of informal localized institutions at a provincial level, in driving the EV transition. The importance of EVs’ economic perspectives in individuals’ likelihood to adopt EVs increased between 2020 and 2023, which is aligned with the considerable influence of rising gasoline prices on the increase of new EV registrations in Canada. The findings of the two analyses raise concerns about whether Canada can achieve its commitment of 100% zero-emissions vehicle sales by 2035 and whether EVs can fully penetrate the Canadian market. The Canadian transition process of EVs is a co-evolutionary process with multiple elements interacting with one another. Therefore, no single policy or action can singly accelerate the process. The heterogeneity across consumers highlights the importance of tailored strategies for different consumer segments and the importance of longitudinal dynamics in investigations. In conclusion, macro-level and micro-level lenses are both important in understanding socio-technical transitions due to their integration, synergy, and complementarity.
Assessing the Compact Polarimetric Capabilities of the RADARSAT Constellation Mission for Monitoring Sub-Arctic Lake Ice Dynamics
(University of Waterloo, 2025-01-20) Dezyani, Saba; Gunn, Grant
Lake ice is a significant aspect of the physical landscape at northern latitudes and plays a crucial role in regulating weather, climate, and supporting various socio-economic aspects. The sensitivity of lake ice development to air temperature makes it an effective indicator of climate change. This phenomenon not only impacts regional weather patterns but also contributes to global environmental shifts. It is important to closely observe variations in lake ice to gain insight into the potential impact that lakes might have on regional weather patterns and environmental conditions. This study focuses on monitoring lake ice dynamics using RADARSAT Constellation Mission (RCM) compact polarimetric data, employing a combination of the first difference method and compact polarimetric (CP) parameter analysis. The research centers on three Canadian sub-Arctic lakes, with a primary focus on Kluane Lake, and examines phenological transitions through changes in backscatter intensity and CP parameters such as Degree of Polarization (DoP), Circular Polarization Ratio (CPR), Relative Phase, and Alpha Angle. The results reveal that freeze-onset and melt-onset events, mapped using the first difference method, align well with validation data from Landsat thermal imagery and meteorological records, highlighting the reliability of RCM data. Additionally, CP parameter analysis provides deeper insights into ice surface and subsurface conditions. DoP and CPR captured variations in surface roughness, while Relative Phase and Alpha Angle distinguished subsurface scattering and ice-water transitions. Mid-winter stability, reflected by minimal variability in CP values across parameters, emerged as the most consistent pattern, signifying coherent solid or snow-covered ice surface. The results highlight the capacity of RCM data to capture key phenological events, demonstrating strong consistency with optical and thermal data sources. However, the research also identifies limitations related to the temporal resolution of RCM data.
Examining the Effects of Soil Moisture on Carex aquatilis Productivity in a Saline Reclaimed Fen in the Athabasca Oil Sands Region
(University of Waterloo, 2025-01-14) Mohammad, Sarah Abdulkareem; Petrone, Richard
The Nikanotee fen is an experimental, constructed peatland in the region, established as a research site to develop strategies for future reclamation projects. Its main challenges include poor water quality caused by elevated salinity levels, which pose significant risks to the survival of its vegetation community. Carex aquatilis (C.aquatilis), a species of particular interest, is notable for its ability to tolerate diverse hydrochemical conditions, including high sodium concentrations. This study aimed to evaluate the effects of soil moisture on various chlorophyll fluorescence and gas exchange productivity parameters of C.aquatilis in the saline environment of the Nikanotee fen, with the goal of providing insights for its potential use in future reclamation projects in the AOSR. Through the use of a portable photosynthesis system, daily measurements of chlorophyll fluorescence (Fv/Fm, Fv’/Fm’, and φPSII) and gas exchange parameters (E, a, and Amax) were conducted to monitor the effects of soil moisture and water table depth in the varying moisture plots on C.aquatilis. The findings of this study determined that while varying moisture levels may not directly impact the productivity of C.aquatilis, they could influence its stress responses by enabling the species to develop adaptations suited to the surrounding moisture conditions. This is demonstrated by the statistically significant decreases in the stress ratio (Fv/Fm) during the heat wave observed in C.aquatilis grown in the ‘Moderate’ moisture plot compared to those in the ‘Dry’ and ‘Wet’ plots. Additionally, this study revealed that C.aquatilis may employ different salt tolerance mechanisms depending on moisture conditions. Plants grown in the ‘Wet’ moisture plots exhibited a higher sodium concentration in their aboveground biomass than in their belowground biomass compared to those in the ‘Dry’ and ‘Moderate’ plots, while still maintaining a statistically significantly higher φPSII and Amax values. These results demonstrate the resilience of C.aquatilis and its ability to sustain essential productivity levels for survival in increasingly reclaimed saline wetlands, such as the Nikanotee Fen.
Quantifying distribution of above ground biomass estimates in forested areas across LiDAR applications and multiple scales
(University of Waterloo, 2025-01-14) Srikumar, Srishanth; Robinson, Derek
Accurate quantification of forest biomass is essential for understanding carbon dynamics, preserving biodiversity, and advancing Nature-based Solutions (NbS) in Canada (Seddon et al., 2020). NbS harness, protect, or restore natural ecosystems to address complex environmental challenges. This thesis leverages LiDAR-derived point cloud data to estimate above-ground biomass (AGB), acknowledging that accuracy varies among different LiDAR sensors due to limitations like point density and survey altitude. We evaluated the effectiveness of three remote sensing technologies—Remotely Piloted Aircraft (RPA) LiDAR, aerial LiDAR, and Global Ecosystem Dynamics Investigation (GEDI) satellite LiDAR in estimating AGB across two distinct forested properties, Ballyduff Trails and Christie Bentham Wetland Trails. These remote sensing estimates were compared with traditional in-situ measurements to assess their accuracy and reliability. Using statistical models and data processing algorithms, we derived AGB estimates from the LiDAR data. Results indicated that both RPA and Aerial LiDAR provided extensive spatial coverage but tended to underestimate AGB compared to in-situ measurements, likely due to the omission of smaller and understory trees. Aerial LiDAR measured higher average tree heights, effectively capturing upper canopy structures, while RPA LiDAR's higher point density facilitated detailed ground-level analysis. Despite its lower spatial resolution, GEDI satellite LiDAR offered a balance between coverage and accuracy, with estimates aligning closely with in-situ values for larger-scale assessments. This study makes a novel contribution by being among the first to compare these three LiDAR technologies across different forest types in Canada. The findings have significant implications for improving forest management practices, informing conservation strategies, and enhancing carbon accounting methods. By highlighting the strengths and limitations of each remote sensing method, we provide valuable insights for their application in sustainable forest management and climate change mitigation initiatives.
Exploring the Use of Managed Retreat in Canada's Policy Domain
(University of Waterloo, 2024-12-19) Cottar, Shaieree; Wandel, Johanna
The use of managed retreat is growing and will continue to evolve within Canada’s policy domain to better adapt to the realities of climate change. Climate induced managed retreat involves the strategic relocation of people, assets and critical infrastructure from high-risk areas via the use of government funded property acquisitions (buyouts). Amid increased flood risks and rising recovery costs, communities in Canada have recognized that conventional approaches to flood risk management (FRM) are no longer sustainable and will require the use of practical policy solutions, such as managed retreat, that are cost-effective, politically viable, and publicly accepted. Given the growing adaptation deficit in municipalities, there is an inherent need to identify the policy gaps and barriers to implementation, analyze the policy levers, and explore opportunities for future managed retreat policy and program development. Rooted in the climate change adaptation and disaster risk reduction literature, this dissertation explores the theoretical tenets of FRM, particularly the lack of alignment between flood risk governance, risk reduction and risk prevention through the empirical application of post-disaster managed retreat policies in Canadian communities. The current policy discourse in Canada focuses on the development of a subsidized national flood insurance program whilst provincial jurisdictions like British Columbia (BC) are contending with how to amend existing disaster and emergency management policies to effectively integrate community led managed retreat. Similarly, provinces like Quebec have significantly advanced in their progress and have implemented multiple buyout cycles as part of their disaster financial assistance programs. By analyzing multiple case studies across different timeframes during their recovery process, this dissertation investigates the complex post-disaster decision-making process amongst different levels of government and explores potential pathways towards building climate resiliency. Through three interrelated qualitative studies, this research documents the development, application and implementation of managed retreat buyout programming and its wider implications for communities. The findings suggest that flood disasters often act as focusing events and open policy windows during the post disaster recovery stage providing an avenue for renewed disaster recovery discussions including the use of managed retreat as a policy tool which may not be politically justifiable in a proactive context. A case study analysis critically documents the recovery process by analyzing municipal perspectives on managed retreat and flood mitigation signaling a shift from a hazards-based to a risk-informed approach in Merritt, Canada after the 2021 flood disaster. Moreover, existing path dependencies and outdated disaster policies can favour recovery decisions and limit the types of mitigation measures that are considered by jurisdictions. Likewise, the development of a buyout program for flood mitigation purposes should account for design considerations that include community led and pricing methodologies that follow an equity-based approach. While the use of buyouts is an important tool to become climate resilient, partially retreated communities must strategically develop land use plans that reconcile the benefits of floodplain restoration and provide recreational spaces for public use. A longitudinal study analyzes the institutional alignment of provincial buyouts policies and regulatory tools in Gatineau, Canada, five years after the Quebec Spring 2019 floods. In broader terms, this dissertation ascertains that in the face of surging disaster costs and conflicting governmental priorities, the use of managed retreat will continue to grow and evolve within the Canadian policy arena as a viable climate adaptation and risk reduction strategy. As a result, this critique presents novel approaches for evaluating managed retreat policies to minimize the negative impacts on communities whilst maximizing the co-benefits. Moreover, this dissertation makes key contributions to the managed retreat literature by linking the topics of flood risk governance, flood risk management, and applied policy. The research provides valuable insights for policymakers on buyout policy development, program implementation, and long-term land use plans for communities in Canada.
Into the Woods: Investigating the Effects of Weather Information and Attentiveness on Outdoor Recreational Activities
(University of Waterloo, 2024-11-22) Woods, Kyle; Andrey, Jean; Mills, Brian
Responses to quick-onset atmospheric weather hazards, including thunderstorms, are influenced by the characteristics of risk messages and the characteristics of the message receivers. Message characteristics relating to the probability of and imminency of thunderstorm impacts, as well as the severity of the information and use of wireless emergency alerts are thought to influence responses through amplifying recipients’ risk perceptions. Receiver characteristics relating to past experiences, knowledge and preparedness, sociodemographic characteristics, among others, also play an influential role in the hazard-response cycle. However, the complex role that recipients’ attentiveness has in this hazard-response cycle has not been adequately addressed. This thesis investigates the role that attentiveness and thunderstorm information messaging play in outdoor recreational activity responses. For this investigation, an experiment consisting of a hypothetical hiking activity under an evolving thunderstorm threat was carried out in an online survey of a sample of 476 adult respondents who regularly camp and hike in southern Ontario during the thunderstorm season. Respondents received relevant weather information through a forecast displayed on a smartphone screen before the hike and subsequent watches (1 hour later) and warnings (2 hour later) during the hike, constituting three scenarios. Correspondingly, half of the respondents received a severe thunderstorm watch consisting of higher-severity information and a wireless emergency alert notification with a subsequent severe thunderstorm warning. Respondents' attentiveness, risk perceptions, and behavioural response intentions were recorded following each scenario and comparisons were made between responses from the common and higher-severity message conditions groups to investigate the effect of higher-severity information and WEAs across a thunderstorm event. Receiver characteristics thought to potentially influence observed relationships between attentiveness, risk perceptions, and behaviours during the specific experimental situation were also explored to provide a more complete understanding of the pathways of influence to behavioural responses during thunderstorm events. Empirical results illustrate that outdoor recreationists are highly attentive and responsive to thunderstorm information; whereas most respondents are unlikely to go ahead with a hike following a weather forecast mentioning the risk of severe thunderstorms. Official severe thunderstorm watch alerts increased respondents' attentiveness to the weather and led to increased proactive protective action likelihoods by most of the remaining participants. Wireless emergency alerts did not change respondents' attentiveness to severe thunderstorm warnings. The pathways of influence to protective actions show that attentiveness amplifies risk perceptions, which acts as a mediator to behavioural response intentions. Individuals' receiver characteristics affected the observed pathways of influence to protective actions. Most notably, respondents’ general weather attentiveness greatly amplified their likelihood to be attentive to the weather during a thunderstorm event and amplified their likelihood to take protective actions. The conclusions of this research underscore the importance of attentiveness in the hazard-response cycle and the need for easier accessibility and exposure to weather forecasts and official alerts in outdoor recreational areas to increase attentiveness and desirable behavioural responses.
Carbon Emissions and Evaporation Dynamics at Peatlands Under Active Extraction in Alberta and Quebec, Canada
(University of Waterloo, 2024-11-20) Hunter, Miranda; Strack, Maria; Strachan, Ian
The extraction of peatlands for horticultural peat use is a small but important source of peatland drainage in Canada, converting these long-term net sinks of carbon (C) into net sources. With demand for peat expected to grow over the coming decades, there is a need to understand how C emissions and water exchange vary with environmental and site management conditions. Extraction operations alter the site hydrology, peat physical and thermal properties, and peat substrate quality, which in turn alter the C cycling and water budget; however, few studies have quantified this. As part of site preparation for extraction, the surface vegetation is removed and a series of drainage ditches are installed to lower the water table, allowing machinery to access the sites. Exterior ditches surround the perimeter of the sites, while interior ditches run the length of the sites, dividing them into 30 m wide fields of peat bounded by ditches. Sites will be extracted for 15 to 40 plus years using the vacuum harvesting method. As part of this, companies repeatedly disturb the surface by harrowing (tilling) the top ~ 5 cm layer to cut it off hydrologically from the peat below. A portion of this newly dry layer is then harvested, processed and sold for use as a horticultural growing medium. This study conducted plot and ecosystem scale measurements of carbon dioxide (CO2), methane (CH4) and evaporation (E) at multiple actively extracted peatlands of varying extraction durations at sites in both Alberta (AB) and Quebec (QC). Specifically, the research objectives were to: i) investigate spatial distribution and seasonal and interannual patterns of C emissions (Chapters 2 and 3); ii) understand the impact of site management, including drainage, harrowing and drainage ditch maintenance, on C fluxes (Chapters 2 and 3) and E (Chapter 4) and iii) assess the environmental drivers of C emissions and E (Chapters 2, 3 and 4). Plot scale C emissions at AB, and ecosystem scale C and E measurements at AB and QC, were conducted for multiple years between 2019 and 2022, with a focus on the March to October period. A peat incubation experiment and a lysimeter experiment were conducted during summer 2022 at AB to understand the impact of substrate quality on C emissions, and the impact of harrowing on E rates, respectively. Water table depth (WTD), volumetric water content (VWC), soil temperature, and a range of atmospheric variables were also measured throughout the study period. We found that while C emissions did not vary spatially across fields, drainage ditches were hotspots of C loss, emitting around double, and ten times the CO2 and CH4 emissions, respectively, of the fields across a range of VWC. Carbon dioxide emission varied by up to 50% seasonally and interannually, with differences driven by the interaction between soil temperature and moisture conditions. Our results demonstrated the importance of characterizing hydrological conditions at drained sites, as the temperature dependence of CO2 emissions increased with increasing moisture content, and CO2 emissions were significantly higher under heavily drained (WTD > 60 cm) conditions. A non-linear relationship between WTD and E demonstrated the strong upward capillary water movement in these heavily compacted sites, and how adequate surface moisture conditions for E can be maintained across a range of WTDs. Site specific WTD thresholds aided in classifying the relative importance of surface and atmospheric variables on E rates. The impact of harrowing on E rates varied with time, which highlighted the importance of considering the length of time between harrowing and harvesting for management operations. This work will have implications for national greenhouse gas reporting, providing data to support updating C emission factors for Canada. The research can be used by industry partners to inform management practices that balance harvesting yields with C emissions. Additionally, due to the absence of vegetation, these study sites provide a unique opportunity to understand environmental controls of heterotrophic respiration and peatland E, without having to partition out the impact of vegetation.
Social Resilience to Flooding: A Case Study of Material Stocks in Surrey, British Columbia
(University of Waterloo, 2024-10-25) Vong, Stephanie; Tan, Su-Yin
The United Nations 2030 Agenda for Sustainable Development is a call for international action towards social, economic, and environmental sustainability. The integration of different sustainable development goals can alleviate the impacts of climate change and advance the development of more sustainable infrastructure and resilient communities. One of the core impacts of warmer global temperatures is rising sea levels and increased severity and frequency of storms. As part of the Sustainable Development Goals (SDG) 9, 11 and 13 is to strengthen infrastructure and community resilience to improve the adaptive capacity of cities related to climate hazards. The research examines the impacts of climate change, specifically flooding and sea level rise, on the City of Surrey. It employs a spatial methodology using LiDAR data to create a Digital Elevation Model, identifying vulnerable areas and infrastructure. The study uses Geographic Information Systems (GIS) to quantify material stocks in buildings and roads potentially affected by flooding. Key findings indicate that significant portions of buildings (12.59%) and roads (27.17%) would be impacted under various flood scenarios, particularly in regions like Crescent Beach and Cloverdale. The study estimates substantial losses in material stocks associated with different return periods and sea level rises. Additionally, a social flood resilience index reveals that areas with low resilience, marked by older populations and economic challenges, are concentrated in Cloverdale and South Surrey, while more resilient areas are found in Newton and Fleetwood. This analysis emphasizes the importance of linking social factors to flood risk, aiming to inform planning and policy for enhancing community resilience against climate hazards.
Assessing changes in peatland plant community functions following seismic line disturbance of different ages
(University of Waterloo, 2024-09-25) Bao, Jie; Strack, Maria; Goud, Ellie
Seismic lines are linear clearings created for petroleum exploration mostly across boreal peatlands and forests in northwestern Canada. Seismic line disturbance has resulted in significant environmental impacts, including changes in plant composition, predator-prey dynamics, and hydrological conditions. There are more than 1.8 million km of seismic lines in Alberta, Canada, and they often remain visible even after decades. Despite the extensive occurrence of seismic lines, their effects on peatland plant community functions remain poorly understood. This study uses a trait-based approach to explore the impact of seismic line disturbance on peatland plant community functions. We measured key morphological plant traits, such as specific leaf area (SLA) and leaf dry matter content (LDMC), along with leaf chemical composition, such as nitrogen (N) and carbon (C). Vegetation cover was also assessed to understand species distribution across disturbed and undisturbed areas. Statistical analyses, including multivariate methods, were conducted to determine how seismic line disturbance influences plant traits and community composition. The results indicate that seismic lines are on a positive recovery trajectory, as reflected by the similarities in both plant community composition and plant traits between undisturbed areas and the areas that have naturally regenerated for about 30 years. However, it does not imply that the peatlands have returned to their pre-disturbance state after three decades. The findings of this study have important implications for the restoration of boreal peatlands disturbed by seismic lines. While restoration strategies like mounding may accelerate ecosystem recovery, these interventions themselves can cause further disturbance. Therefore, it is crucial to balance the time required for natural recovery with the potential disturbances introduced by restoration efforts.
Disentangling and Demystifying Illegal Wildlife Trade and Crime Convergence
(University of Waterloo, 2024-09-24) Anagnostou, Michelle; Doberstein, Brent
Illegal wildlife trade represents a significant and growing form of organized crime. In recent years, illegal wildlife trade has been increasingly reported as being perpetuated by the same people trafficking in drugs, humans, and arms, and committing acts of terrorism, a phenomenon often labelled “crime convergence”. However, limited empirical research has been conducted to understand the extent and nature of these convergences. This doctoral dissertation addresses that knowledge gap. This dissertation makes significant advancements in crime convergence theory and enriches the global empirical data. Through four interrelated studies, this dissertation illustrates that illegal wildlife trade is a complex form of crime that relates to a myriad of other serious and organised crime activities. The results also indicate that convergences themselves can take many forms, and therefore should be considered with a nuanced lens. The dissertation advocates for the adoption of more collaborative approaches to mitigate converging crimes. The studies also highlight that tectonic shifts are required to prioritise illegal wildlife trade more appropriately, and to combat the dynamic and innovative strategies of wildlife traffickers more effectively.
Identifying the Imprint of Climate Change on Low-Arctic Rivers from Planform Changes of the Colville River, Alaska
(University of Waterloo, 2024-09-24) Serrano, Pedro; Lewis, Quinn; Robinson, Derek; Gunn, Grant
The undeniable effect of climate change is prevalent in countless number of natural processes occurring across our planet, particularly within the circumpolar region. These climatic shifts have had an impact on internal and external forces that drive river movement. Hence, channel activities within these regions would, presumably, also change in response. Using the Colville River, situated in northern Alaska, USA, as a study site, the research first identifies the climatological trends occurring within the region. Temperature, precipitation, and discharge from the year 2002 to 2019 are examined to identify how these internal and external factors have changed throughout the years. Additionally, channel activities of two reaches within the river are also calculated within the same period using Landsat data. These variables are then correlated amongst each other to identify how one factor influences the other. Trends are captured on both a continuous (short-term) and a yearly (long-term) timeframe, whereby the continuous timeframe presents the data in a monthly sequential period from 2002 to 2019 while the yearly timeframe compares the data of each month across the years. Finally, the same approach was completed using Planet satellite imageries, where data is available, to verify the result. The findings show an overall increase in temperature primarily during the winter months, increase in frequency of precipitation towards the more recent years, and both an increase and decrease in discharge during the freezing and thawing period, respectively. Furthermore, the calculation shows a strong positive correlation between discharge and temperature (r = 0.63, r2 = 0.39, p-value = 4.64e-17) for the continuous, short-term, timeframe and a relatively strong negative correlation (r = -0.57, r2 = 0.32, p-value = 1.88e-5) for the yearly, long-term, timeframe. The positive correlation between the two variables in the short-term timeframe shows the seasonal relationship between temperature and discharge, whereby as the temperature increases, discharge also increases in response. Interestingly, however, the long-term timeframe suggests that as the temperature increases, discharge decreases in response. This was identified as the effect of climate change that is caused by the increase in temperature during the freezing months. Discharge is starting to take place throughout the year, therefore it is hypothesized that during the thawing months most ice have already melted which results in an overall decrease in discharge during the freezing months. And given the relatively strong positive correlation of discharge and channel activity for the short-term timeframe (Reach A: r = 0.62, r2 = 0.62, p-value = 1.02e-16 and Reach B: r = 0.68, r2 = 0.46, p-value = 2.65e-19), it is expected that channel movement will soon follow such decrease in discharge trend in the long run. These findings suggest that semi-arctic braided rivers, the Colville River in particular, are transitioning to river movements more similar to rivers situated in temperate climate, whereby activity is not only prevalent during the thawing months but will soon be identifiable throughout the year.
Assessing Tree Carbon Estimates from Remotely Piloted Aircraft-Based LiDAR: A Comparison of Quantitative Structural Models and Allometric Scaling with In-Situ DBH Measurements
(University of Waterloo, 2024-09-23) Liu, Chenxi; Robinson, Derek
Forest carbon storage estimation is critical for global climate change mitigation efforts, as forests play a vital role in the carbon cycle. This study investigates the accuracy of using Remotely Piloted Aircraft (RPA)-based LiDAR for estimating tree Diameter at Breast Height (DBH) and carbon storage through 3D tree modeling techniques. Two Quantitative Structure Models (QSM) — TreeQSM and AdQSM were used to virtually reconstruct trees and estimate tree and forest carbon stocks, with comparisons made to in-situ DBH measurements and traditional Allometric Scaling Models (ASMs), including self-developed allometric equation database and i-Tree Eco. Data were collected from two forest sites with different tree densities in Ontario, Canada, under leaf-on and leaf-off conditions. Result indicates that AdQSM generally outperformed TreeQSM in estimating DBH, particularly in less dense forests and during leaf-off season, where the correlation with in-situ DBH measurements improved. Despite variation in results from the two models, RPA-based LiDAR demonstrated potential as a scalable and non-destructive tool for forest carbon estimation, providing a foundation for future advancements in localized ASMs. The findings highlight the importance of accurate tree parameter extraction for forest carbon accounting, aligning with global efforts in climate change mitigation and sustainable forest management.

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