Communities and Sustainability

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https://hdl.handle.net/10388/14359

Understanding the relationships among different peoples and the natural world and ensuring that they are maintained in a good way — a philosophy embodied in the Cree/Saulteaux concept of wahkohtowin — is crucial to overcoming urgent environmental, social, and political hurdles.

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Oxidative Stability of Novel Peptides (Linusorbs) in Flaxseed Meal-Fortified Gluten-Free Bread
(Foods, 2025-01) Shim, Youn Young; Burnett, Peta-Gaye G.; Olivia, Clara M.; Zou, Xianguo; Lee, Sung Jin; Kim, Hye-Jin; Kim, Young Jun; Reaney, Martin
Flaxseed meal, rich in water-soluble gums, improves the texture of gluten-free (GF) products. Bioactive antioxidant peptides from flaxseed, known as linusorbs (LOs) or cyclolinopeptides, may provide health benefits. However, the stability of flaxseed-derived LOs during dough preparation, baking, and storage remains unclear. To investigate this, GF bread dough and bread were prepared with flaxseed meal, and the LO content was determined in the flaxseed meal, the bread flour with the flaxseed meal, the dough, and the bread. The LO levels were also monitored during storage at various temperatures (−18 °C, 4 °C, and 22–23 °C) for 0, 1, 2, and 4 weeks using high-performance liquid chromatography–diode array detection (HPLC-DAD). The levels of oxidized LOs, such as [1–9-NαC],[1-(Rs,Ss)-MetO]-linusorb B2 (LO14), remained relatively stable in the flaxseed meal and the flour derived from it across under all conditions for up to 4 weeks. Due to microbial contamination, the dough could not be stored at either 4 or 21 °C, and the bread could only be stored at 21 °C for one week. However, the bread and dough could be stored for up to 4 weeks at −18 °C, and the bread at 4 °C, without a significant loss of LOs. The main changes in LOs occurred during processing rather than storage. Reduced LOs were found in higher concentrations in the flour and meal compared to the dough and bread, without a corresponding increase in oxidized LOs. The flaxseed meal-fortified bread maintained oxidative stability when stored at low temperatures. This is the first study to investigate the effect of baking conditions on LO content and antioxidant properties.
A comparison of seasonal flexibility in pectoralis muscle fiber type and enzyme activity in migratory and resident sparrow species
(Journal of Experimental Biology, 2024-02) Lewicki, Louisa M.; Zhang, Marina; Staples, James; Guglielmo, Christopher G.; Ivy, Catherine
The pectoralis muscle in birds is important for flight and thermogenesis. In migratory songbirds this muscle exhibits seasonal flexibility in size, but whether this flexibility reflects changes in muscle fiber type has not been well documented. We investigated how seasonal changes in photoperiod affected pectoralis muscle fiber type and metabolic enzymes, comparing among three closely related sparrow species: two seasonal migrants and one year-round, temperate climate resident. We quantified fast oxidative glycolytic (FOG) and fast glycolytic (FG) fibers histologically, and measured activities of citrate synthase (CS) and lactate dehydrogenase (LDH) in the pectoralis muscle of the three species that were acclimated to long or short periods of daylight. In all species, FOG was the predominant fiber type, but song sparrows had FG fibers regardless of daylight conditions. By contrast, Lincoln's sparrows incorporated FG fibers only under short-daylight conditions, and house sparrows did not significantly express FG fibers, regardless of daylight length. Both migratory species increased LDH activity in short-daylight conditions but did not alter CS activity. In contrast, resident house sparrows did not alter CS or LDH activity with changes in daylight length. Our findings suggest that the presence of FG fibers is important for seasonal flexibility in LDH activity. Additionally, migratory species exhibited seasonal flexibility in muscle fiber type and enzyme activity, presumably to support migratory flight, while the resident species did not exhibit such seasonal flexibility, suggesting that this consistent phenotype is important year-round, despite changing thermogenic requirements.
The TRANSECTS Programme with a reflection on Evaluation in Social-Ecological Landscapes
(2024) Rosenberg, Eureta; Blackie, Mags; Cockburn, Jessica; Ngwenya, Dudu; Kuse, Mzukise
Collaboratively training transdisciplinary scholars and practitioners: Exploring challenges and opportunities in the COVID-19 pandemic context.
(International Transdisciplinarity Conference: Creating Spaces And Cultivating Mindsets For Learning And Experimentation., 2021-09) Reed, Maureen; Cockburn, Jessica; Mora, Constanza; Mvulane, Wandile; Robson, James; Rosenberg, Eureta; Lotz-Sisitka, Heila
Bridging theory and practice through Transdisciplinary Learning Labs to build sustainability competencies in higher education
(World Environmental Education Congress, 2024) Rosenberg, Eureta
Pockets of Social Innovation in Landscapes of Fear?
(2024) Rosenberg, Eureta; Mtati, Nosiseko
Learning how to Learn - Conservation Organisation’s Strategies
(2024) Rosenberg, Eureta
Evaluating Sustainability Learning Interventions: Implications for System Building
(2021) Rosenberg, Eureta
Can Monitoring and Evaluation Advance our Education, Advocacy and Action?
(Environmental Education Association of Southern Africa (EEASA), 2023) Rosenberg, Eureta
A reflective question posed as part of an NRF CoP Project of the Environmental Learning Research Centre at Rhodes University - Towards Transformative Monitoring, Evaluation and Learning in Landscapes
Ice roads and income in remote indigenous communities of Canada
(Elsevier, 2025-02-01) Ahmed, Fatma
I estimate the effects of ice road length deviation on the level of income in the Northwest Territories communities. The harsh weather conditions and extreme climates in the NWT magnify the challenges associated with maintaining infrastructure, often undermining its long-term benefits. I find that the disruptions in ice roads, which serve as vital links for northern Canadian communities, exacerbate income inequality by placing a greater burden on low-income households while disproportionately favoring higher-income groups. Education is a critical factor in driving income growth and reducing inequality. Conversely, reliance on social assistance notably reduces income for higher-income families, while it provides a boost for those in need. Larger communities, however, experience more severe economic challenges, especially within lower-income groups.
Microbial protein production during fermentation of starch-rich legume flours using Aspergillus oryzae and Lactobacillus plantarum starter cultures
(Journal of Bioscience and Bioengineering, 2025-01-24) Kryachko, Yuriy; Arasaratnam, Lashmitha; House, James Duncan; Ai, Yongfeng; Nickerson, Michael Todd; Korber, Darren Raymond; Tanaka, Takuji
Starch-rich faba bean, yellow lentil, and yellow field pea flours were subjected to submerged fermentation using Aspergillus oryzae and Lactobacillus plantarum starter mono- or co-cultures, to increase protein contents of the flours. Fermentation mixes were supplemented with up to 35 g/L urea, ammonium sulfate and/or monoammonium phosphate as nitrogen sources. Protein contents of the flours increased 2–2.5-fold, i.e., total protein contents of up to 33 % were achieved following fermentation with A. oryzae monoculture or A. oryzae‒L. plantarum co-culture. Therefore, A. oryzae was capable of efficient legume starch utilization and protein production. Using A. oryzae‒L. plantarum co-culture led to the highest yields of at least six of microbially produced amino acids. After fermentation by L. plantarum monoculture, protein contents remained largely unchanged. However, in vitro protein digestibility of flours improved to a greater extent after fermentation with L. plantarum monoculture than with either A. oryzae monoculture or the co-culture. Hence, during fermentation with L. plantarum monoculture, microbially mediated hydrolysis of legume protein (generating smaller and easier digestible peptides), rather than microbial starch utilization, was the predominant process.
Chiral nematic cellulose nanocrystal films: Sucrose modulation for structural color and dynamic behavior
(International Journal of Biological Macromolecules, 2025-01) Babaeighazvini, Amin; Vafakish, Bahareh; Acharya, Bishnu
This study explores the effect of sucrose addition on the properties of chiral nematic cellulose nanocrystal (CNC) films for potential food industry applications, including biodegradable packaging and food coloring. The addition of sucrose altered the films' structural color, shifting from blue in pure CNC films to aqua blue, green, yellow-green, and red with increasing sucrose concentrations (up to 21 %). Surface analysis revealed a reduction in contact angle from 96° to 48° due to sucrose's hydrophilic nature and smoother film surfaces. XRD results indicated a decrease in crystallinity from 84.5 % to 15.6 %, linked to the disruption of CNC alignment by sucrose. Mechanical testing showed reduced tensile strength (138 MPa to 35 MPa) and Young's modulus (1.634 GPa to 70 MPa) with higher sucrose content. Notably, over the storage time, films with 21 % sucrose exhibited dynamic structural coloration caused by localized sucrose recrystallization, leading to pitch shifts and color transitions. These findings demonstrate the tunable optical and mechanical properties of CNC-sucrose films, positioning them as promising materials for sustainable food packaging and responsive coatings.
The Ecology and Evolution of Beavers: Ecosystem Engineers That Ameliorate Climate Change
(Annual Review of Ecology, Evolution, and Systematics, 2024) Fairfax, Emily; Westbrook, Cherie
Beavers, Castor canadensis in North America and Castor fiber in Eurasia, are widely referred to as nature's engineers due to their ability to rapidly transform diverse landscapes into dynamic wetland ecosystems. Few other organisms exhibit the same level of control over local geomorphic, hydrologic, and ecological conditions. Though freshwater ecosystems are particularly vulnerable to changing climate, beavers and their wetland homes have persisted throughout the Northern Hemisphere during numerous prior periods of climatic change. Some research suggests that the need to create stable, climate-buffered habitats at high latitudes during the Miocene directly led to the evolution of dam construction. As we follow an unprecedented trajectory of anthropogenic warming, we have the unique opportunity to describe how beaver ecosystem engineering ameliorates climate change today. Here, we review how beavers create and maintain local hydroclimatic stability and influence larger-scale biophysical ecosystem processes in the context of past, present, and future climate change.
Migration strategy and constraint in migration behavior vary among shorebird species with different life histories
(Wiley, Ecological Society of America, 2025-01-15) Clements, Sarah J.; Loghry, Jason P.; Linscott, Jennifer; Ruiz, Jorge; Gunn, Joe; Navedo, Juan G.; Senner, Nathan; Ballard, Bart; Weegman, Mitch
Migration strategy is a key behavioral characteristic guiding how migratory species time their annual cycles and use habitat. Understanding variation in migration strategy within and among species and individuals can be useful for understanding how birds navigate energetic trade-offs and designing or modifying conservation plans meant to benefit multiple species and life histories. We compared migration strategies among three migratory shorebird species with variable life history traits and short, medium, and long migration distances, respectively: American avocets (Recurvirostra americana), black-bellied plovers (Pluvialis squatarola), and Hudsonian godwits (Limosa haemastica). Avocets (short distance) exhibited the most within-species variation in migration duration, proportion of migration time spent at stopovers, and stopover duration. Plovers (medium distance) and godwits (long distance) showed less variation in these metrics, but godwits showed the most variation in the number of stopovers used. There were significant differences among species in migration distance, number of stopovers used, proportion of time stopped over, departure and arrival dates, and migration duration, but not mean stopover duration. We also found that avocets spent more time stopped over relative to migration distance than plovers or godwits, indicating that avocets showed the most energy-minimizing strategy of the three species. Our findings set the stage for future work assessing the effects of climate change and land use on characteristics associated with different migration strategies for additional migratory species.
Sub-zero soil CO2 respiration in biostimulated hydrocarbon-contaminated cold-climate soil can be linked to the soil-freezing characteristic curve
(Environmental Science and Pollution Research, 2025-01) Nayeema, Tasnim; Lee, Aslan Hwanhwi; Richter, Amy; Ng, Kelvin Tsun Wai; Chang, Wonjae
Extending unfrozen water availability is critical for stress-tolerant bioremediation of contaminated soils in cold climates. This study employs the soil-freezing characteristic curves (SFCCs) of biostimulated, hydrocarbon-contaminated cold-climate soils to efficiently address the coupled effects of unfrozen water retention and freezing soil temperature on sub-zero soil respiration activity. Freezing-induced soil respiration experiments were conducted under the site-relevant freezing regime, programmed from 4 to − 10 °C at a seasonal soil-freezing rate of − 1 °C/day. The effects of unfrozen water retention on extending soil respiration activity emerged at the onset of soil-freezing. The unfrozen water effect became significant below 0 °C (correlation r = 0.83–0.94) and comparable to the temperature effect (correlation r = 0.82–0.90), successfully demonstrating the coupled effects on sub-zero respiration activity. Soil CO2 respiration modelling based on the temperature dependency only (Arrhenius and Q10 models) did not accurately describe sub-zero respiration activity associated with increased unfrozen water retention in treated contaminated soils. The shifted SFCCs of the treated soils, expressed as a function of soil temperature (T) and unfrozen water content (θ), served as a key framework for efficiently developing the sub-zero respiration model (SFCC-RESP). The developed SFCC-RESP model closely approximated the changes in soil respiration rates influenced by T and θ in the treated soils (R2 = 0.94–0.98) and described the abrupt decrease and subsequent stabilization in CO2 production during the transition to the deeply frozen soil phase. The SFCC-RESP model integrated with soil thermal models (TEMP/W) can be used to produce spatial distributions of T, θ, and CO2 production in the treated soil matrix, providing a tool to approximate the abundance of unfrozen habitable niches when developing cold-tolerant bioremediation strategies.
Sustainability in the Arctic: A Bibliometric Analysis
(Discover Sustainability, 2024-05) Ahmed, Fatma; Zapata, Oscar; Poelzer, Greg
This paper examines the literature on the Sustainability in the Arctic region, using a bibliometric analysis of 213 English- language articles published between 1980 and 2022 exploiting Bibliometrix, an R package. To find relevant literature using the Web of Science (WOS) database, we searched for documents using mesh terms based on the query of two terms, “Arctic & Sustainability”. We used the Boolean operator “AND” to combine the two terms and the Boolean operator “OR” to include synonyms of the terms. The articles retrieved were authored by 724 researchers, published in 98 journals, representing 132 countries, and growing at 5.08% annually. The findings reveal that a substantial portion of the Arctic sustainability literature placed significant emphasis on the examination of climate change, adaptation, and vulnerabilities affecting local communities. Furthermore, the more recent publications in this field concentrate predominantly on exploring perceptions and governance.
Effect of snow cover on the off-host survival of Dermacentor variabilis (Acari: Ixodidae) larvae
(Journal of Medical Entomology, 2024-01) Diyes, Chulantha P; Yunik, Matthew E M; Dergousoff, Shaun J; Chilton, Neil
The geographical range of the American dog tick, Dermacentor variabilis (Say), in Canada continues to expand northwards into areas with colder winter temperatures. Understanding what influences the off-host survival of D. variabilis over winter is important for predicting the northern distributional limit of this species. A field experiment was conducted to determine the effect of snow cover on the off-host survival of unfed D. variabilis larvae from a population situated near the northern distributional limit in Saskatchewan, Canada. Ticks were placed in tubes within 1 of 9 field enclosures (tickaria) in early fall. The 9 tickaria were divided into 3 equal treatment groups: no snow cover, natural snow cover (maximum depth of 25 cm) and extra snow cover (maximum depth of 32 cm). Tick survival was measured in mid-winter and in early spring (i.e., ~17 and ~26 wk after start of experiment). The results showed that snow cover had a significant impact on the relative humidity, but not temperature, in the tickaria. Larvae in tickaria with no snow cover had a higher mortality rate (27%) than larvae in tickaria with natural snow cover (6%) or extra snow cover (4%). Although snow cover enhanced off-host survival, many individuals were able to survive in sub-zero temperatures under leaf litter in the absence of continuous snow cover for a period of 108 days. These findings have implications for the construction of predictive models to determine the northern distributional limits of D. variabilis, a species that is an important vector of several pathogens.
Disparity in low-flow trends found in snowmelt-dominated mountain rivers of western Canada
(Journal of Hydrology: Regional Studies, 2024-12) Whitfield, Paul; Pomeroy, John W
Study region A complex mountainous region that is the source of water for the major river basins of northwestern North America. Study focus Trends in magnitudes and timing of annual low flows in relation to basin characteristics and climate indices in 106 nival rivers in British Columbia and Alberta. New hydrological insights Two types of significant trends in annual low flows were observed: [1] decreased magnitude and earlier occurrence in the warmer southwest, or [2] increased magnitude and later occurrence in the colder, higher elevation north and east. These differences are associated with differences in the form of nival regime from the reliable cold winter and spring freshet of the north and east to regimes with fall and mid-winter melts, often associated with rainfall, in the south and west. Basin location and regional climate, rather than individual basin attributes such as elevation or hypsometry drove these differences in streamflow regimes and their responses to climate variations and warming. Atmospheric teleconnections had strong effects that corresponded to the regime and spatial differences in trends and were dominated by positive relationships between magnitude and timing with long duration indices (AMO & PDO), and negative relationships with short duration climate indices (NAO & SOI). The pattern of these relationships mimicked the temporal trends over time, positive with magnitude and timing in the northeast, and negative in the southwest.
Intraspecies variation in mycorrhizal response of Medicago sativa to Rhizophagus irregularis under abiotic stress
(Mycorrhiza, 2024-12-13) Kuper-Psenicnik, Aisa; Bennett, Jonathan
Plant partnerships with arbuscular mycorrhizal fungi (AMF) improve plant resilience to stress by increasing the plant’s access to and uptake of essential nutrients and water, as well as regulating the plant’s stress response. The magnitude and direction of AMF effects during the relationship depend on multiple factors including plant identity and environmental context. To investigate how AMF influence plant responses to environmental stresses, we assessed the effects of drought and salinity on growth, final biomass, and reproduction of nine alfalfa (Medicago sativa) cultivars inoculated with Rhizophagus irregularis or grown alone. In absence of stress, the fungus increased nutrient content, but caused declines in biomass through a reduction in initial growth that was not overcome by a later growth spurt. Mycorrhizal fungus inoculation also magnified stress effects on growth in most scenarios, but this depended on the stress type and cultivar. For salinity, this stress increase in inoculated plants was mediated by increased salt accumulation. Flowering of each cultivar was affected by both inoculation and stress type, albeit erratically, whereas seed production was only affected by inoculation when drought stressed. We found no clear pattern distinguishing differences in mycorrhizal fungus effects on stress among cultivars; however, our results show that mycorrhizal fungus effects on plant stress responses are contingent on the plant performance metric and stress type, highlighting the complexity of responses to mycorrhizas.
Comparison of the supercooling points of questing Dermacentor variabilis adults in two populations on the Canadian prairies and implications for overwinter survival
(Springer Nature, 2023-12-12) Yunik, Matthew Edward Marks; Diyes, Chulantha P.; Chilton, Neil
A comparison was made of the supercooling points (SCPs) of questing Dermacentor variabilis adults from two populations located ca. 800 km apart on the Canadian prairies. This is also the first study to examine whether there are seasonal fluctuations in the SCP of questing D. variabilis adults. The SCPs of adult ticks from Lizard Lake Community Pasture, a recently established population in west-central Saskatchewan, varied over spring and summer, with the median SCP warming over time. In addition, the SCPs of ticks from Lizard Lake Community Pasture were significantly higher than those of adult ticks collected from Sandy Hook in Manitoba, a population that has been established for decades. The off-host survival of adults from Sandy Hook between summer and spring has been shown previously to be significantly greater than that of adults from Lizard Lake Community Pasture. The findings of the present study suggest that there may be geographical variation in the SCPs of D. variabilis adults which may be associated with differences in overwinter survival. The relatively low SCPs of questing D. variabilis adults, and the ability of some adults to survive off-host during winter, may be factors contributing to the range expansion of this tick species in Canada.

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