From Micro to Macro: Insights into Biogeochemical Mechanisms that Shape Marine Systems

Biogeochemical mechanisms employed by key organisms, or symbiotic associations of organisms, transform the function and structure of their environment through processes recognized as ecosystem engineering. This dissertation seeks to investigate organism-ecosystem interactions that serve globally significant ecological functions in marine systems and impact how systems respond to environmental change. Using two model ecosystems that are quite unique from one another, deep-sea methane seeps and tropical coral reefs, I consider the ecosystems from a bottom up perspective, constraining the biogeochemical interactions that manifest in the hotspots of production and complexity associated with both of these systems. Through investigating seep systems that span the Cascadia margin in the N.E. Pacific, I reveal never before seen latitudinal variations in the microbial communities at the center of globally relevant seep processes, highlighting connections to the persistent oxygen minimum zone of the region, and increase the biogeographic ranges of two key seep taxa. Expanding these results, I explore the trophic connectivity of the chemosynthetic production that is at the base of seep systems to commercially important, non-seep fauna typically connected to sparse food supply from surface production in the food-limited deep-sea. With this, I provide the first evidence of the assimilation of seep-derived chemosynthetic nutrition by commercially harvested species in the deep sea and provide crucial context on the importance of the ecosystem provisioning services of seeps to overall ocean health and productivity. I also reveal a methodological bias that may have underestimated the contribution of seep nutrition to deep-sea fauna in past studies, elucidating the importance of matching the spatial and temporal scales of methods used with the interactions being studied. I then shift to tropical coral reef ecosystems and employ both field- and experiment-based methodologies to identify a novel mechanism in coral decline, wherein coral bleaching releases globally significant amounts of dissolved organic carbon that fundamentally alters the biogeochemistry of the reef scape. This in turn ignites a positive feedback mechanism of coral mortality, with consequences that are substantial enough to impact global carbon budgets. Overall, my dissertation uses multiple systems to identify the variability and flow of energy through marine ecosystems through both disparate habitats and episodic events that together inform the function of the marine realm

Workplace Violence in Emergency Departments: Addressing Barriers to Reporting Through Education

Background: Workplace violence (WPV) in emergency departments is a national health care concern. Nurses practicing in emergency departments are at greater risk for violence than other health care professionals. Published literature suggests that WPV is underreported because of inadequate understanding of its definition and associated reporting processes, which contributes to a lack of evidence-based interventions to reduce its frequency. Purpose: Consistent utilization of a reporting database can assist in identifying trends in emergency departments’ violence occurrences and subsequent interventions, as reviewed by the organization’s WPV Committee. WPV education was offered with the intent of improving reporting accuracy and promoting better understanding of WPV. The WPV Committee’s lack of engagement was addressed. Methods: Emergency department employees and leaders were offered education on the definition and reporting process of WPV through a free continuing nursing education module. The WPV Committee was simultaneously tasked with updating policies and creating engagement strategies to reduce WPV. Evaluation: Reporting system effectiveness was measured by comparing the frequency of documented occasions of violence before and after an educational intervention. Continuing nursing education pre- and posttest score comparison via paired t test was used to gauge WPV and reporting process knowledge. The WPV Committee’s participation was increased. Clinical Implications: Utilization of a consistent WPV definition and reporting process aided accuracy of incident reports, exemplifying a culture that supports reporting incidents. This practice can inform data-driven interventions, when funneled through the WPV Committee, to reduce WPV, and may contribute to a safer emergency department environment for employees.D.N.P., Nursing Practice -- Drexel University, 201

Examining Elementary School Children’s Knowledge about Food and Nutrition in Southwestern Ontario, Canada

Purpose: Knowledge is fundamental to helping children make nutritional choices that support lifelong healthy behaviours. This study (i) investigates elementary school children’s knowledge about food and nutrition and (ii) identifies sociodemographic factors influencing children’s reported knowledge. Methods: In 2017–2019, a survey was administered to 2443 students (grades 5–8) at 60 schools across southwestern Ontario, Canada, and a parent survey was used to validate self-reported sociodemographics. Multiple regression was used to analyse children’s knowledge scores and related sociodemographic factors. A total knowledge score was calculated by summing correct responses derived from 46 individual questions in the student survey. Results: Mean total knowledge score was 29.2 out of a possible 46 points (63.5% correct). Students demonstrated some knowledge and awareness of strategies to encourage fruit and vegetable consumption, healthy food selection, nutrition, and food preparation skills, although knowledge of food guide recommendations and locally sourced produce were limited. Female sex, family income, and rurality were associated with higher knowledge scores. Conclusions: Results provide insight regarding strengths and gaps in elementary-school children’s food and nutrition knowledge. Poor performance of students on specific food guide-related questions suggests that the general guidance of the 2019 Canada’s Food Guide might be better understood by children and adolescents

Children’s perceptions of a centrally procured school food program in southwestern Ontario, Canada

Introduction: This qualitative study investigates children’s perceptions of the influences of a Centrally Procured School Food Program on their dietary behaviours and their recommendations on how to improve the program. Methods: The observations of 208 students aged 9 to 14 years (Grades 5–8) at 21 elementary schools were collected through focus groups in 2017/18. The larger intervention consisted of a 10-week program offering daily snacks (i.e. fruit, vegetables, whole grains, dairy, meat alternatives) for elementary school children in southwestern Ontario, Canada. Results: The participants’ overall impressions of the program were positive. They noted reduced hunger, increased energy and improved nutrition. Many children felt that the program changed their dietary patterns at home as well as at school, particularly in terms of eating more fruit and vegetables. The snack program also enabled children to try healthy foods. Conclusion: Most participants considered the program to be beneficial in promoting healthy eating. Participants recommended adding educational activities, expanding the variety of foods and increasing child involvement in selecting and preparing foods

Children’s perceptions of a centrally procured school food program in southwestern Ontario, Canada

Introduction: This qualitative study investigates children’s perceptions of the influences of a Centrally Procured School Food Program on their dietary behaviours and their recommendations on how to improve the program. Methods: The observations of 208 students aged 9 to 14 years (Grades 5–8) at 21 elementary schools were collected through focus groups in 2017/18. The larger intervention consisted of a 10-week program offering daily snacks (i.e. fruit, vegetables, whole grains, dairy, meat alternatives) for elementary school children in southwestern Ontario, Canada. Results: The participants’ overall impressions of the program were positive. They noted reduced hunger, increased energy and improved nutrition. Many children felt that the program changed their dietary patterns at home as well as at school, particularly in terms of eating more fruit and vegetables. The snack program also enabled children to try healthy foods. Conclusion: Most participants considered the program to be beneficial in promoting healthy eating. Participants recommended adding educational activities, expanding the variety of foods and increasing child involvement in selecting and preparing foods

The Deep Sea and Me : using a science center exhibit to promote lasting public literacy and elucidate public perception of the deep sea

A critical barrier to effective management of deep-sea resources is a lack of understanding by society of the benefits received from the oceans. To address this knowledge gap, we applied an iterative design-based research methodology to evaluate (1) how to effectively use an exhibit to increase public literacy of the deep sea over the short and long-term and (2) how visitors to a public science center perceive the deep sea. Using observations of visitor interactions and surveys of visitors, we evaluated three iterations of an exhibit that highlighted deep-sea ecosystem services and habitats as a case study of exhibit efficacy. Exhibits containing video and interactive components were effective in communicating deep-sea information that was retained by visitors over the long-term. For many visitors, the exhibit was their first introduction to the deep sea. Visitors agreed it is important to learn about the deep sea and expressed interest in learning more about deep-sea animals, habitats, resources, and benefits to humans. Visitors tended to agree with protection-oriented value statements and disagree with use-oriented value statements toward the deep sea. This study provides insight into how to effectively communicate policy-relevant information about the deep sea to an audience that has little to no prior knowledge of the ecosystem, yet who will be increasingly responsible for making use decisions of this habitat

Flipping for Food: The Use of a Methane Seep by Tanner Crabs (Chionoecetes tanneri)

Methane seep habitats are widespread chemosynthesis-based ecosystems that span continental margins and interact with surrounding marine systems. With many of these habitats occurring below 200 m, seeps can serve as an important source of nutrients in otherwise food limited deep-sea environments. However, the potential for marauding megafauna to assimilate seep derived nutrition has been difficult to quantify. Here, we provide the first evidence of a commercially harvested species, Chionoecetes tanneri (tanner crab), assimilating chemosynthetic production. Although bulk isotope analysis of C. tanneri tissue indicated no quantifiable incorporation of seep-derived carbon or sulfur (mean δ13C, −18.5‰; mean δ34S, 19.5‰), depletions in 13C (δ13C as light as −38.8‰) were noted in fatty acid (FA) compounds. In addition, diagnostic biomarkers for seep bacteria, including 16:1ω6 and 18:1ω8c FA's, were found to have been assimilated by C. tanneri. Futher supporting a trophic link between the seep and the C. tanneri, seep associated bacteria and archaea were, in certain cases, the dominant taxa in the gut contents of the crabs. This work provides the first insights into a link between seep production and deep-sea ecosystem services, specifically fisheries production. In addition, it reveals a methodological bias that could exist in some trophic studies where bulk isotopes under-represent the role of seep nutrition in the diet of marauding animals

Gender equality for a thriving, sustainable arctic

On 21 May 2021, a milestone Pan-Arctic Report: Gender Equality in the Arctic was published in tandem with the Arctic Council’s Ministerial Meeting held in Reykjavík, 19–20 May 2021. This article provides a brief review of the report and its major findings across six chapters that address key themes concerning gender equality in the Arctic: Law and Governance, Security, Gender and Environment, Migration and Mobility, Indigeneity, Gender, Violence, Reconciliation and Empowerment and Fate Control. A major conclusion of the report is that accessible, comparable, gender-disaggregated, and Arctic -specific data is severely lacking. Further, all chapters highlight the importance of gender-based analysis and gender mainstreaming in all decision-making processes at national and regional levels. The varying roles that gender—and its intersections with existing inequalities—plays in mediating the impacts of climate change and other socioeconomic transformations are also discussed throughout the report. The Arctic Council is identified as the main driver for implementing recommendations that were provided and discussed at the Council’s Ministerial Meeting and in the Reykjavík Declaration 2021, where the eight ministers of Arctic states “Emphasize[s] the importance of gender equality and respect for diversity for sustainable development in the Arctic… encourage[s] the mainstreaming of gender-based analysis in the work of the Arctic Council and call[s] for further action to advance gender equality in the Arctic”. This report and its policy relevant highlights, address these priorities and serve as a knowledge base for promoting gender equality and non-discrimination in the Arctic

Estimates of Methane Release From Gas Seeps at the Southern Hikurangi Margin, New Zealand

The highest concentration of cold seep sites worldwide has been observed along convergent margins, where fluid migration through sedimentary sequences is enhanced by tectonic deformation and dewatering of marine sediments. In these regions, gas seeps support thriving chemosynthetic ecosystems increasing productivity and biodiversity along the margin. In this paper, we combine seismic reflection, multibeam and split-beam hydroacoustic data to identify, map and characterize five known sites of active gas seepage. The study area, on the southern Hikurangi Margin off the North Island of Aotearoa/New Zealand, is a well-established gas hydrate province and has widespread evidence for methane seepage. The combination of seismic and hydroacoustic data enable us to investigate the geological structures underlying the seep sites, the origin of the gas in the subsurface and the associated distribution of gas flares emanating from the seabed. Using multi-frequency split-beam echosounder (EK60) data we constrain the volume of gas released at the targeted seep sites that lie between 1,110 and 2,060 m deep. We estimate the total deep-water seeps in the study area emission between 8.66 and 27.21 × 10 6 kg of methane gas per year. Moreover, we extrpolate methane fluxes for the whole Hikurangi Margin based on an existing gas seep database, that range between 2.77 × 10 8 and 9.32 × 10 8 kg of methane released each year. These estimates can result in a potential decrease of regional pH of 0.015–0.166 relative to the background value of 7.962. This study provides the most quantitative assessment to date of total methane release on the Hikurangi Margin. The results have implications for understanding what drives variation in seafloor biological communities and ocean biogeochemistry in subduction margin cold seep sites