Faculty Publications (Social Sciences)

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Includes articles from BioMed Central Click on this link to see Work published with BioMed Central, Chemistry Central and SpringerOpen by researchers at University of Victoria.

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    Psychological mediators of the associations between pandemic-related stressors and suicidal ideation across three periods of the COVID-19 pandemic in Canada
    (Journal of Affective Disorders, 2023) Turner, Brianna; Switzer, Andrew C.; Welch, Brooke E.; Legg, Nicole K.; Gregory, Madeline A.; Phiri, Peter; Rathod, Shanaya; Paterson, Theone S. E.
    Background: The COVID-19 pandemic's mental health impact is well-established. While early evidence suggested suicide deaths remained stable or declined, suicidal ideation (SI) became more prevalent than before the pandemic. Our study: (1) examined the prevalence and distribution of SI among Canadian adults, (2) compared SI among those with and without pre-existing mental illnesses, and (3) evaluated associations between pandemic-related stressors (i.e., unemployment, insecure employment, loss of income, medical vulnerability, COVID-19 exposure) with SI, and whether such associations were mediated by depression, thwarted belongingness, perceived burdensomeness, or perceived discrimination. Methods: The sample was comprised of data gathered at three timepoints (Wave 1 08/18/2020–10/01/2020, n = 6629; Wave 2 12/21/2020–03/31/2021, n = 5920; Wave 3 09/07/2021–12/07/2021, n = 7354). Quota-based responses from survey research panels which matched the geographic, age, and sex distribution of the Canadian population were supplemented with convenience-sampled responses. Results: The prevalence of SI was 4.1 % (Wave 1), 5.3 % (Wave 2), and 5.8 % (Wave 3). Odds of SI were higher for respondents under the age of 35 years and with pre-existing mental illnesses. SI was associated with quarantining due to suspected or confirmed COVID-19 exposure, potential COVID-19 exposure at work, medical vulnerability toward COVID-19, insecure employment or unemployment, and income loss. These associations were mediated by psychological experiences, particularly depression and thwarted belongingness. Limitations: This cross-sectional, observational study cannot establish temporality or causality. Conclusion: Results highlight groups who may benefit from enhanced screening for depression and suicide risk. Reducing depression and increasing sense of belonging should be prioritized.
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    Testing umbrella species and food-web properties of large carnivores in the Rocky Mountains
    (Biological Conservation, 2023) Steenweg, Robin; Hebblewhite, Mark; Burton, Cole; Whittington, Jesse; Heim, Nikki; Fisher, Jason Thomas; Ladle, Andrew; Lowe, Winsor; Muhly, Tyler; Paczkowski, John; Musiani, Marco
    Despite criticisms, the umbrella species concept remains a fundamental conservation tool for protecting biodiversity in the face of global change, yet it is rarely tested. Food web theory provides a tool to test both umbrella-species' suitability and their ecological function, which we investigate in a large-mammal food web. Using data from 698 camera trap locations in the Canadian Rockies, we develop hierarchical occupancy models to predict the co-occurrence of 16 large mammal species. We draw upon previous diet studies in the Canadian Rockies to describe the meta food-web (meta-web) for these species. Next, we filtered the meta-web using predicted occupancy to estimate realized food webs at each camera location. We tested the umbrella species concept using predicted occupancy across all 698 camera sites. We then tested for carnivore effects using realized food webs on 5 food-web properties: species richness, links, connectance, nestedness and modularity using generalized linear models while accounting for landscape covariates known to affect food web dynamics. Our multispecies occupancy models reflected factors previously demonstrated to affect large mammal occurrence. Our results also demonstrated that grizzly bear (Ursus horribilis), a generalist carnivore, was the best umbrella carivore species, and explained species richness the best. When considering food web properties, however, wolves (Canis lupus) and cougars (Felis concolor) served as better umbrellas that also captured food web properties such as connectance, links and nestedness that better reflect ecological interactions. Our results support the role of large carnivores as umbrella and ecologically interactive species in conservation planning.
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    Visualization of atrophy of medial temporal lobes and the septal nuclei in patients with transient ischaemic attack and controls
    (Cerebral Circulation - Cognition and Behavior, 2023) Schaeffer, Morgan J.; Reaume, Noaah; Wang, Meng; Aftab, Arooj; Pan, Alexander; Tariq, Sana; Reid, Meaghan; Smith, Eric E.; D'Esterre, Chris; Barber, Philip A.
    Introduction: Transient ischaemic attack (TIA) is associated with increased risk of cognitive decline and dementia as early as one-year post-event. Regional brain atrophy measurements may predict future cognitive decline. Aims: 1) To determine whether Medial Temporal Atrophy (MTA) scores and interseptal distance (ISD) measurements are greater in patients with TIA compared to controls; and 2) To determine whether MTA and ISD predicts cognitive change one year after TIA. Methods: Baseline demographic, vascular risk factors, structural imaging and cognitive tests scores were compared between 103 Patients with TIA and 103 age-and-sex-matched controls from the Predementia Neuroimaging of Transient Ischaemic Attack (PREVENT) Study. MTA was assessed using the Schelten's Scale, and ISD was calculated as the distance between the septal nucleus of each hemisphere. Multiple linear regression models were used to evaluate how MTA and ISD related to cognitive change after adjusting for covariates. Results: Patients with TIA had larger ISD measurements (1.4 mm [SD=1.2] vs. 0.9 mm [SD=1.0]); p < 0.001) and higher right/left MTA scores (both p < 0.05) compared to controls. At baseline, controls performed significantly better on the RAVLT (total recall), BVMT (total and delayed recall) and the Trail Making Task (A and B) compared to patients with TIA. However, at one-year follow-up there was no evidence of decline in the patients with TIA compared with controls. Higher MTA and ISD scores were not associated with cognitive decline. Conclusions: Patients with TIA had higher MTA scores and ISD measurements than controls, but neither were predictors of cognitive decline at one year. Future studies with longer follow-up periods will be required to determine whether higher MTA scores and ISD predict risk of cognitive decline in patients with TIA.
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    Large weather and conflict effects on internal displacement in Somalia with little evidence of feedback onto conflict
    (Global Environmental Change, 2023) Thalheimer, Lisa; Schwarz, Moritz P.; Pretis, Felix
    Extreme weather and conflict may drive forced displacement. However, their individual contribution to displacement is not fully understood due to challenges around isolating individual channels of causality. Here, we use novel disaggregated data on internal displacement in all of Somalia’s subregions from 2016 to 2018 broken down by reported reason of displacement and combine it with weather and conflict data. This allows us to isolate the effects of extreme weather and conflict on forced displacement, as well as the effects of displacement on conflict itself. We find large non-linear effects of weather on displacement where an increase in temperature anomalies from 1 °C to 2 °C (to approx. 1.5 standard deviations, SD) leads to a tenfold increase in displaced people, and a reduction in precipitation from 50 mm to 0 mm (approx. 1.5SD) leads to around a fourfold increase in displacement. We find significant effects of conflict events on displacement (which are masked when the data is aggregated) with a 1.5 standard deviation increase in conflict events increasing displacement 50-fold. We further show that displacement itself has little detectable effect on the occurrence of conflict events.
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    COVID-19-related stigma and its impact on psychological distress: A cross-sectional study in Wuhan, China
    (Health Science Reports, 2022) Zhou, Min
    Background and Aims: Health-related stigma arises from the perceived association between a person or group of certain characteristics and a specific disease. Coronavirus disease 2019 (COVID-19) has brought about stigma targeted at individuals and groups who are perceived to be connected with the virus. Wuhan of China was not only the locale where the first COVID-19 cases were detected in the world but was also the hardest hit across China. Methods: Using new data (N = 1153) from a survey conducted in Wuhan in August 2020, this cross-sectional study aims to reveal the stigma experienced by residents in Wuhan during the COVID-19 pandemic and the impact of this experienced stigma on psychological distress, specifically posttraumatic stress disorder. Results: 69.47% (95% confidence interval (CI): 66.81%─72.13%) of the surveyed Wuhan residents have experienced some forms of stigma related to COVID-19. The average posttraumatic stress disorder score based on the impact of event scale–revised is 20.28 (95% CI: 19.096─21.468) out of 88. In particular, 27.75% (95% CI: 25.17%─30.34%) of the respondents display clinically significant distress symptoms. Moreover, this stigma not only aggravates individuals' posttraumatic stress disorder score by 10.652 (95% CI: 8.163─13.141) but also elevates the chance of developing clinically significant distress symptoms. Specifically, the probability of clinical distress is significantly higher (p < 0.001) among those who have experienced stigma (33.66%) than those who have no such experiences (12.62%). Conclusion: The public should be aware of the distress-inducing impact of stigma related to COVID-19 and prevent it from causing more harm to certain individuals and groups.
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    Exploring resilience in public services within marginalised communities during COVID-19: The case of coal mining regions in Colombia
    (Journal of Cleaner Production, 2023) Weber, Gabriel; Cabras, Ignazio; Peredo, Ana Maria; Yanguas-Parra, Paola; Prime, Karla Simone
    This paper examines the impact of COVID-19 on marginalised communities and its effects on the provision of public services. Focusing on two coal mining regions in Colombia during the pandemic crisis, and examining Indigenous and Afro-Colombian communities, we analyze the provision of public services at a local level, identifying both shortcomings and resilience. Findings show that the lack of resilient public services amplified the effects of COVID-19 and its containment measures, exacerbating existing structural inequalities within local marginalised communities. It also reinforced the control exercised by coal mining companies within local economies. However, the substantial lack of public service provision also provided space for the development and strengthening of several resilience strategies among local communities, such as solidarity networks and schemes and the revitalization of local environmental knowledge. The study identifies multiple shortcomings in how the national and local administrations handled the COVID-19 outbreak and highlights the potential of enhancing resilience in public services to support marginalised communities in times of crisis.
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    A resilience-based transformations approach to peacebuilding and transformative justice
    (Current Opinion in Environmental Sustainability, 2024) Olsson, Per; Moore, Michele-Lee
    Moving from a state of war or violent conflict will require a transformation, but there are no guarantees that transformations automatically lead to peace, sustainability, and justice. This review focuses on the temporary phase when a system is in limbo between the existing, dominant state and a new alternative state. We combine insights from a resilience approach to transformations with peacebuilding and transformative justice studies to focus on three roles that hybrid approaches to transformative and transitional justice may play in this phase, including 1) addressing ‘backlash’ dynamics, 2) strengthening the capacities needed to navigate cross-scale dynamics of conflict, and 3) responding to additional shocks, crises, and disturbances beyond the primary conflicts. Together, these findings advance the theoretical foundations for understanding peacebuilding as a transformative change process.
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    Accelerated human-induced extinction crisis in the world's freshwater mammals
    (Global Environmental Change Advances, 2024) Torres-Romero, Erik Joaquin; Fisher, Jason Thomas; Nijman, Vincent; He, Fengzhi; Eppley, Timothy M.
    Human activities have significantly impacted natural habitats and wildlife worldwide, particularly emphasizing repercussions for freshwater habitats and associated species. These negative impacts on freshwater fish are well known, but for mammal species that regularly use and dependend on freshwater systems, there is an incomplete understanding. Here, we assessed the status of freshwater and semi-aquatic mammal species inhabiting and dependent on freshwater ecosystems (hereafter referred to as freshwater mammals) and evaluated the impact of human activities on species richness both globally and by biogeographical regions. We used structural equation modeling and simultaneous autoregressive models to assess the direct and indirect effects of seven anthropogenic-related variables on overall freshwater mammal richness. Specifically, we examined the effects of anthropogenic disturbance on the richness of threatened and non-threatened species, as well as species with decreasing and stable/increasing populations. Forty-three percent of all freshwater mammal species are classified as globally threatened by the IUCN Red List, with 50% experiencing population declines. Furthermore, 48% are affected by domestic or international trade, while 75% face threats from geographically expanding human activities. Aridity, pesticide pollution, human footprint, and croplands had the strongest negative effects on freshwater mammal richness. In contrast, the coverage of freshwater habitats (FWs), Indigenous Peoples' lands (IPLs), and protected areas (PAs) helped to sustain freshwater mammal species globally, with an even stronger positive effect at individual biogeographical regions. We conclude that FWs, IPLs, and PAs play a critical role in the conservation of freshwater mammal species, helping safeguard these species from extinction, however, freshwater ecosystems are seldom the focal point of conservation management strategies. The ongoing adverse anthropogenic impacts on these natural habitats present a potentially catastrophic and irreversible threat to global freshwater environments and the species, including humans, reliant upon them. We strongly advocate for the implementation of more robust national and international policy frameworks that endorse alternative and sustainable livelihoods. Such frameworks can play a crucial role in alleviating anthropogenic pressures, thereby aiding in the mitigation of the extinction risk faced by these vital ecosystems and the world's freshwater mammal species.
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    Keeping up with COVID-19 information: Capacity issues and knowledge uncertainty early in the pandemic
    (Canadian Review of Sociology / Revue canadienne de sociologie, 2023) Albert, Katelin; Gray, Garry
    This article examines the relationship between information consumption and mental health during the early stages of the COVID-19 pandemic. Adopting a qualitative approach, we interviewed 39 people in British Columbia, Canada between October and December 2020. Interestingly, half of the participants did not want to seek out new information on COVID-19, making their early insights and initial confusion salient. While some individuals did desire up-to-date information on outbreaks and new risks, many expressed confusion over what was perceived to be an evolving landscape of public health policy and practice. Overall, our research found that capacity issues, information overload/fatigue, politics, distrust, and competing sources of news all contributed to a culture of confusion towards public health information. As a consequence, this confusion resulted in knowledge uncertainty about the virus, vaccinations, and the pandemic itself. Our findings highlight the need for a host of future projects that examine how citizens experience disempowerment and limited agency towards compliance with health and safety initiatives.
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    Influence of mountain pine beetle outbreaks on large fires in British Columbia
    (Ecosphere, 2024) Woo, Hyeyoung; Bone, Christopher; Nadeem, Khurram; Taylor, Stephen W.
    A key uncertainty in understanding climate change effects on wildfires in western North America is the role of mountain pine beetle (MPB) outbreaks in driving wildfire occurrence and severity. In this study, we investigated the complex relationship between MPB outbreaks, other environmental factors, and wildfire occurrence in British Columbia (BC), Canada. We adopted a fire risk analysis method developed for fire occurrence prediction to separate the effect of changing fuel conditions on wildfires in BC when neither post-outbreak fuel conditions, climate, nor management is stationary. Using lasso-logistic regression and a novel variable ranking procedure, we determined that MPB-affected areas had 1.7 times more large lightning-caused fires (≥100 ha), as the likelihood of large lightning-caused fires increased by 40% in these areas and likely contributed to the increased burned areas in BC. Meanwhile, the likelihood of large human-caused fires decreased in MPB-affected areas. Fire weather factors were most influential for both lightning- and human-caused fires, while anthropogenic factors were most influential for human-caused fires. Fuel dynamics following MPB outbreaks vary across the wide distribution of a host species such as lodgepole pine, at stand and landscape levels. Furthermore, the expression of the effects of MPB and other disturbances on wildfire is also conditional on, as well as confounded with, many other environmental factors and management activities that vary across western North America. Therefore, a lack of consensus on the impacts of MPB on wildfire is not surprising.
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    Fine resolution classification of new ice, young ice, and first year ice based on feature selection from Gaofen-3 quad-polarization SAR
    (Remote Sensing, 2023) Yang, Kun; Li, Haiyan; Perrie, William; Scharien, Randall Kenneth; Wu, Jin; Zhang, Menghao; Xu, Fan
    A new method of sea ice classification based on feature selection from Gaofen-3 polarimetric Synthetic Aperture Radar (SAR) observations was proposed. The new approach classifies sea ice into four categories: open water (OW), new ice (NI), young ice (YI), and first-year ice (FYI). Seventy parameters that have previously been applied to sea ice studies were re-examined for sea ice classification in the Okhotsk Sea near the melting point on 28 February 2020. The ‘separability index (SI)’ was used for the selection of optimal features for sea ice classification. Full polarization parameters (the backscatter intensity contains the horizontal transmit-receive intensity (σ⁰ₕₕ), Shannon entropy (SEᵢ), the spherical scattering component of Krogager decomposition (Kₛ)), and hybrid polarization parameters (horizontal receive intensity(σ⁰ᵣₕ), hybrid-pol Shannon entropy (CPSEᵢ), the correlation coefficient (pᵣₕ−ᵣᵥ) between the σ⁰ᵣᵥ and σ⁰ᵣₕ, and the surface scattering component of m − α decomposition (αₛ)) were determined as the optimal parameters for the different work modes of SAR. The selected parameters were used to classify sea ice by the random forest classifier (RFC), and classification results were validated by manually interpreted ice maps derived from Landsat-8 data. The classification accuracy of OW, NI, YI and FYI reached 95%, 96%, 98% and 85%, respectively.
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    A remote sensing view of the 2020 extreme lake-expansion flood event into the Peace-Athabasca Dela floodplain—implications for the future SWOT mission
    (Remote Sensing, 2023) Desrochers, Nicholas M.; Peters, Daniel L.; Siles, Gabriela; Charest, Elizabeth Cauvier; Trudel, Mélanie; Leconte, Robert
    The Peace–Athabasca Delta (PAD) in western Canada is one of the largest inland deltas in the world. Flooding caused by the expansion of lakes beyond normal shorelines occurred during the summer of 2020 and provided a unique opportunity to evaluate the capabilities of remote sensing platforms to map surface water expansion into vegetated landscape with complex surface connectivity. Firstly, multi-source remotely sensed data via satellites were used to create a temporal reconstruction of the event spanning May to September. Optical synthetic aperture radar (SAR) and altimeter data were used to reconstruct surface water area and elevation as seen from space. Lastly, temporal water surface area and level data obtained from the existing satellites and hydrometric stations were used as input data in the CNES Large-Scale SWOT Simulator, which provided an overview of the newly launched SWOT satellite ability to monitor such flood events. The results show a 25% smaller water surface area for optical instruments compared to SAR. Simulations show that SWOT would have greatly increased the spatio-temporal understanding of the flood dynamics with complete PAD coverage three to four times per month. Overall, seasonal vegetation growth was a major obstacle for water surface area retrieval, especially for optical sensors.
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    A multi-satellite mapping framework for floating kelp forests
    (Remote Sensing, 2023) Gendall, Lianna; Schroeder, Sarah B.; Wills, Peter; Hessing-Lewis, Margot; Costa, Maycira
    Kelp forests provide key habitat on the Pacific Coast of Canada; however, the long-term changes in their distribution and abundance remain poorly understood. With advances in satellite technology, floating kelp forests can now be monitored across large-scale areas. We present a methodological framework using an object-based image analysis approach that enables the combination of imagery from multiple satellites at different spatial resolutions and temporal coverage, to map kelp forests with floating canopy through time. The framework comprises four steps: (1) compilation and quality assessment; (2) preprocessing; (3) an object-oriented classification; and (4) an accuracy assessment. Additionally, the impact of spatial resolution on the detectability of floating kelp forests is described. Overall, this workflow was successful in producing accurate maps of floating kelp forests, with global accuracy scores of between 88% and 94%. When comparing the impact of resolution on detectability, lower resolutions were less reliable at detecting small kelp forests in high slope areas. Based on the analysis, we suggest removing high slope areas (11.4%) from time series analyses using high- to medium-resolution satellite imagery and that error, in this case up to 7%, be considered when comparing imagery at different resolutions in low–mid slope areas through time.
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    Assessing climatic drivers of spring mean and annual maximum flows in western Canadian river basins
    (Water, 2021) Dibike, Yonas B.; Shrestha, Rajesh R.; Johnson, Colin; Bonsal, Barrie; Coulibaly, Paulin
    Flows originating from cold and mountainous watersheds are highly dependent on temperature and precipitation patterns, and the resulting snow accumulation and melt conditions, affecting the magnitude and timing of annual peak flows. This study applied a multiple linear regression (MLR) modelling framework to investigate spatial variations and relative importance of hydroclimatic drivers of annual maximum flows (AMF) and mean spring flows (MAMJflow) in 25 river basins across western Canada. The results show that basin average maximum snow water equivalent (SWEmax), April 1st SWE and spring precipitation (MAMJprc) are the most important predictors of both AMF and MAMJflow, with the proportion of explained variance averaging 51.7%, 44.0% and 33.5%, respectively. The MLR models’ abilities to project future changes in AMF and MAMJflow in response to changes to the hydroclimatic controls are also examined using the Canadian Regional Climate Model (CanRCM4) output for RCP 4.5 and RCP8.5 scenarios. The results show considerable spatial variations depending on individual watershed characteristics with projected changes in AMF ranging from −69% to +126% and those of MAMJflow ranging from −48% to +81% by the end of this century. In general, the study demonstrates that the MLR framework is a useful approach for assessing the spatial variation in hydroclimatic controls of annual maximum and mean spring flows in the western Canadian river basins. However, there is a need to exercise caution in applying MLR models for projecting changes in future flows, especially for regulated basins.
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    Climatic controls on mean and extreme streamflow changes across the permafrost region of Canada
    (Water, 2021) Shrestha, Rajesh R.; Pesklevits, Jennifer; Yang, Daqing; Peters, Daniel L.; Dibike, Yonas B.
    Climatic change is affecting streamflow regimes of the permafrost region, altering mean and extreme streamflow conditions. In this study, we analyzed historical trends in annual mean flow (Qₘₑₐₙ), minimum flow (Qₘᵢₙ), maximum flow (Qₘₐₓ) and Qₘₐₓ timing across 84 hydrometric stations in the permafrost region of Canada. Furthermore, we related streamflow trends with temperature and precipitation trends, and used a multiple linear regression (MLR) framework to evaluate climatic controls on streamflow components. The results revealed spatially varied trends across the region, with significantly increasing (at 10% level) Qₘᵢₙ for 43% of stations as the most prominent trend, and a relatively smaller number of stations with significant Qₘₑₐₙ, Qₘₐₓ and Qₘₐₓ timing trends. Temperatures over both the cold and warm seasons showed significant warming for >70% of basin areas upstream of the hydrometric stations, while precipitation exhibited increases for >15% of the basins. Comparisons of the 1976 to 2005 basin-averaged climatological means of streamflow variables with precipitation and temperature revealed a positive correlation between Qₘₑₐₙ and seasonal precipitation, and a negative correlation between Qₘₑₐₙ and seasonal temperature. The basin-averaged streamflow, precipitation and temperature trends showed weak correlations that included a positive correlation between Qₘᵢₙ and October to March precipitation trends, and negative correlations of Qmax timing with October to March and April to September temperature trends. The MLR-based variable importance analysis revealed the dominant controls of precipitation on Qₘₑₐₙ and Qₘₐₓ, and temperature on Qₘᵢₙ. Overall, this study contributes towards an enhanced understanding of ongoing changes in streamflow regimes and their climatic controls across the Canadian permafrost region, which could be generalized for the broader pan-Arctic regions.
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    Examining the hydro-climatic drivers of lagoon breaching and healing in a deltaic barrier
    (Geosciences, 2023) Gomez, Juan Felipe; Kwoll, Eva; Walker, Ian J.; Orejana, Andres F.
    As sea-level rise (SLR) and human-made interventions affect coastal currents and sediment transport, coastal barriers have become more vulnerable to the effect of storms, hurricanes, and climate variability. The response of each barrier is unique and depends on wave regime, coastline orientation, weather conditions, bathymetry, and type of human-made interventions, among other factors. In the Magdalena River deltaic barrier, located on the Colombian Caribbean coast, coastal erosion has caused the loss of hundreds of square kilometers of critical ecosystems, such as wetlands and lagoons, since the 1960s. This work aims to analyze the short-term drivers behind the observed loss of lagoons, particularly the drivers of lagoon breaching events and subsequent healing along the deltaic barrier. Lagoon breaching events and healings were detected using satellite imagery, and the timing of these events was related to prior local atmospheric, oceanographic, and fluvial conditions. The findings reveal that the dynamics of the lagoons are driven by extreme river discharges and energetic wave conditions associated with storms or hurricanes. Healing is driven by the sediment supplied by littoral currents and average waves punctuated by energetic events. The cumulative effect of breaching and healing has resulted in a deltaic barrier that has rolled over the lagoons, reducing their size over time. These findings provide a better understanding of the forces of coastal retreat and will help inform future management decisions of the coastal zone.
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    Effects of climate change on navigability indicators of the lower Athabasca River, Canada
    (Water, 2023) Peters, Daniel L.; Dibike, Yonas B.; Shudian, Joseph; Monk, Wendy A.; Baird, Donald J.
    The lower Athabasca River (Canada) has experienced notable declines in streamflow and increasing oil sands development since the 1970s. This study investigates the potential impacts of climate change on navigability using both observed historical and projected future flows derived via hydrological simulations driven by an ensemble of statistically downscaled general circulation model climate data. Our use of proposed indices that form the Aboriginal Navigation Index (ANI) and a new index based on percentage over threshold (POT) occurrences yielded novel insights into anticipated changes to the flow regime. Comparisons of near (2041–2070) and far (2071–2100) future periods with the historical baseline (1981–2010) yielded results that project significant reductions in the 500 m³ s⁻¹ POT during the fall navigability period spanning weeks 34 to 43, as well as reductions in the integrated ANIFall. These results indicate that challenging navigational conditions may become more frequent in the second half of the 21st century, not only during this fall period but also earlier into the summer, due to a shift in the flow regime, with potentially severe impacts on the users of the river channels. Our assessment approach is transferable to other regional study areas and should be considered in water management and environmental flow frameworks.
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    Cyanobacteria index as a tool for the satellite detection of cyanobacteria blooms in the Baltic Sea
    (Remote Sensing, 2023) Konik, Marta; Bradtke, Katarzyna; Stoń-Egiert, Joanna; Soja-Woźniak, Monika; Śliwińska-Wilczewska, Sylwia; Darecki, Miroslaw
    Cyanobacteria blooms in the Baltic Sea have been studied for years due to their toxicity, which negatively affects all biota, along with the influence of these floating colonies on surface fluxes. However, mapping these blooms is still a challenge since their high dynamics, wide coverage, and specific radiometric footprint hinder atmospheric correction and negatively affect the quality of satellite images. In this study, we assessed the use of an alternative approach called the cyanobacteria index (CI), which is based on the reflectance spectral shape and which does not require comprehensive atmospheric correction. We demonstrated a close relationship between the positive CI values, indicating the presence of blooms, and the concentration of phycocyanin, the marker pigment of filamentous cyanobacteria in the Baltic Sea. We proved that the CI index could efficiently identify cyanobacteria-dominated blooms where colonies floated near the surface. Therefore, this index represents a valuable complement to the previous monitoring methods, suitable for extreme bloom events. The analysis of a time series of satellite images obtained between 2002 and 2018 using the CI index revealed the elongation of the bloom season, which may have been a consequence of the water temperature remaining within the cyanobacteria’s tolerance range for a longer time.
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    Incident and recurrent depression among older adults with asthma during the COVID-19 pandemic: Findings from the Canadian Longitudinal Study on Aging
    (Respiratory Medicine, 2023) MacNeil, Andie; Li, Grace; Jiang, Ying; de Groh, Margaret; Fuller-Thomson, Esme
    Objectives: (1) In a subsample of older adults with asthma without a history of depression, to determine the factors associated with developing depression during the COVID-19 pandemic; (2) in a subsample of older adults with asthma with a history of depression, to identify factors associated with recurrent depression during the pandemic. Methods: Data came from four waves (Baseline [2011–2015], Follow-up 1 [2015–2018]; COVID Spring 2020, COVID Autumn 2020) of the Canadian Longitudinal Study on Aging's comprehensive cohort (n = 2,047 with asthma). The outcome of interest was a positive screen for depression based on the CES-D-10 during the autumn of 2020. Bivariate and multivariate logistic regression analyses were conducted. Results: Among older adults with asthma without a history of depression (n = 1,247), approximately 1 in 7 (13.5%) developed depression for the first time during the COVID-19 pandemic. Among those with a history of depression (n = 770), approximately 1 in 2 (48.6%) experienced a recurrence of depression. The risk of incident depression and recurrent depression was higher among those who were lonely, those experiencing family conflict during the pandemic, and those who had difficulty accessing healthcare resources during the pandemic. The risk of incident depression only was higher among those who had difficulty accessing resources and/or loss of income during the pandemic. The risk of recurrent depression only was higher among those with functional limitations. Conclusions: There is a need for targeted interventions to support the mental health of older adults with asthma who have the above identified vulnerabilities during the pandemic.
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