Dal Events

M.Sc. Thesis Defence: Dr. Cody Paige

Tue, 07 Apr 2026 12:00:00 GMT

M.Sc. Thesis Defence

Dr. Cody Paige
Department of Earth and Environmental Sciences, ȫ��̽��

Title: Combining cosmogenic nuclide depth profiles and in situ 14C to measure erosion-adjusted exposure ages of sedimentary landforms

Abstract: In situ cosmogenic 14C offers a unique window into the recent erosion and burial histories of sedimentary landform surfaces due to its short mean life (ca. 8,223 yr) relative to other terrestrial cosmogenic nuclides (TCNs). This short mean life makes.14C sensitive to erosion and burial processes over the past 25-30 kyr- timescales that are poorly resolved by longer-lived nuclides such as 10Be and 36Cl. Here I present a novel approach to estimate erosion rates on late Pleistocene alluvial fan and shoreline surfaces in Pana mint Valley, California, by measuring 14C saturation concentrations in detrital quartz sand from amalgamated sediment samples collected just below the soil mixing zone. Sample locations were guided by soils and geomorphic observations at four sites. I also describe the development and testing of a 14C extraction line at ȫ��̽��, including validation against the known inter-laboratory standard, CRONUS-A. Erosion rate uncertainty improved by up to 50% compared to soils geomorphology-based estimates, providing tighter constraints on 10Be depth profile exposure ages at the same sites. Comparison of 14C-derived erosion rates with independent 10Be and 36Cl depth profile ages suggests that previous field-based erosion rate estimates may have significantly underestimated uncertainty in paleo-erosion histories. These results demonstrate the utility of in situ 14C saturation measurements as a practical and powerful complement toconventional TCN depth profile dating of alluvial fan surfaces in arid environments, with broader implications for landscape evolution studies in tectonically active regions.

Examining Committee:
Dr. Gary Salazar Quintero, University of Ottawa, External Examiner
Dr. John Gosse, ȫ��̽��, Supervisor
Dr. Owen Sherwood, ȫ��̽��, Reader
Dr. Eric Kirby, Penn State University, Reader
Dr. Melissa Schwab, ȫ��̽��, Defence Chair

EES Graduate Poster Symposium

Thu, 09 Apr 2026 17:45:00 GMT

The annual graduate poster symposium will be next Thursday April 9, 2:45-5:00pm at the Social (former U-club).

The poster symposium is an opportunity for graduate students in EES to share their research with each other and the department, so please come out to support and celebrate the outstanding research being done here.

The Marcos Zentilli prize will be awarded for the best poster at each of the MSc and PhD levels to help advance graduate student research. Other awards will also be announced.

Snacks and refreshments will be provided.

ERTH6300 PhD Proposal Defences

Fri, 10 Apr 2026 12:00:00 GMT

Every year our EES graduate students formally defend their thesis proposals in April. This year it will take place on April 10.

This is your chance to glimpse the novel and world class research that is ongoing in our department. The defence is open to the public.

This year there are only 2 PhD students, so we are offering 20 minute presentations, followed by 40 minutes of questioning.

EES Honours Qualifying Exam

Fri, 10 Apr 2026 12:00:00 GMT

EES Ph.D. Research Seminar: Alexandra Del Favero-Campbell

Fri, 10 Apr 2026 14:00:00 GMT

Ph.D. Research Seminar
Department of Earth and Environmental Sciences
ȫ��̽��

Alexandra Del Favero-Campbell
Ph.D. Candidate

Title: The Effect of Environmental Factors on Mental Health in Nova Scotia

Abstract: Nova Scotia reports among the highest rates of mental health disorders in Canada, yet the environmental determinants of this burden remain incompletely characterized. While biological predisposition plays a role, environmental factors, like poor air quality and limited greenspace, are linked to increased mental health risks. Chronic geogenic metal exposures, notably arsenic (As), lead (Pb), and manganese (Mn) in both soils and private well water, represent an understudied pathway that may contribute to population level variation in mental health. This PhD project aims to disentangle the relationships between environmental stressors and mental health outcomes in Nova Scotia. This research investigates the role of chronic environmental exposure to heavy metals and metalloids originating primarily from geogenic sources in private drinking well water, as an understudied contributor. The central hypothesis guiding this work is that long term exposure to individual metals and to complex metal mixtures potentially act as neurotoxicants, increasing risk for mood and anxiety-related outcomes in adults, via a cascade that begins with oxidative stress status and systemic inflammation and progresses to neurotoxicity, with mixture patterns and long-term trace element status potentially modulating effects.

This Ph.D. thesis utilizes regional longitudinal data from two cohort studies, the Atlantic Partnership for Tomorrow's Health Study (PATH) and the Canadian Longitudinal Study on Aging (CLSA), as well as biological samples through a multi-project framework to better understand disparities, identify disease mechanisms, and explore interventions to mitigate metal exposure and reduce mental health inequalities in Atlantic Canada. Project 1 is a scoping review that maps geographic and methodological gaps in the arsenic–mental health literature, with a specific focus on studies conducted within the Americas. Project 2 links area weighted well water metal concentrations to Atlantic PATH participants’ standardized mental health measures and integrates relevant CLSA biomarker observations. Project 3 applies Bayesian Kernel Machine Regression (BKMR) to toenail metal measurements from Atlantic PATH participants to estimate overall mixture effects, explore non-linear exposure–response relationships, and identify metals that contribute most strongly to poor mental health risk. This third project also attempts to examine long-term trace element nutritional status in participants as a proxy to assess oxidative stress status overtime to potentially identify vulnerabilities based on nutritional status and environmental exposure. Collectively, these projects delineate geographically defined environmental risks for mental health in Atlantic Canada, identify specific metals and mixture signatures warranting further study, and provide an evidence base to inform targeted surveillance and mitigation strategies.

Biography: Alex completed her Bachelor of Science in Biology at Purdue University in 2013. Originally from Hawaii, her deep-rooted passion for species conservation and environmental health in her hometown led her to explore the anthropogenic effects on wildlife behavior, specifically focusing on insect species as part of her undergraduate research. This foundational interest in environmental health and human-wildlife interaction propelled her into international study, resulting in two research-based Master of Science degrees. The first was in Conservation Science from the University of Queensland in Australia, and the second was in Sustainability and the Bioeconomy, specializing in Natural Science, Engineering, and Environmental and Food Law, from the University of Hohenheim in Germany. Before beginning her doctoral work, Alex further diversified her interdisciplinary portfolio by performing research in collaboration with various institutions, including the U.S. Army and the EPA to explore the impacts of urbanicity on the health and ecology of freshwater stream systems. She also investigated critical links between extreme heat exposure and epigenetic aging in people with severe mental health disorders. Her current Ph.D. research at ȫ��̽�� focuses on the critical public health issue of chronic metal exposures and their associations with mental health outcomes in Nova Scotia, which she has received a funding award as a Scotia Scholar to pursue from Research Nova Scotia. Throughout her academic career, Alex has demonstrated exceptional dedication to student leadership and mentorship. She has actively mentored graduate students within her department and the ȫ��̽�� Neuroscience department, and has served as a University of Hawaii research mentor for programs supporting high school and undergraduate students of native Hawaiian descent to enable early involvement in scientific research. She is also a very active member of ȫ��̽��'s BIPOC Graduate Student Mentoring Academy. Outside of academics, Alex is committed to giving back to her community. She regularly volunteers at her favorite community soup kitchen when she is visiting her family. She also enjoys spending time traveling with her family and caring for her pets.

EES Honours Qualifying Exam

Sat, 11 Apr 2026 12:00:00 GMT