Browsing by Author "Vamosi, Jana C."
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Item Open Access Assessing Temperature Tolerance in Ninespine Stickleback (Pungitius pungitius) in Response to Climate Change(2018-07-13) Tufts, Teresa; Rogers, Sean M.; Yeaman, Sam; Vamosi, Jana C.; Murray, Maribeth S.Temperature is the most important environmental factor influencing fish abundance and distribution but, as temperatures rise globally, the consequences for fishes remains largely unknown. I used populations of ninespine stickleback (Pungitius pungitius) from the northern and southern parts of their range in a common environment to characterize thermal traits in association with varying temperatures. Cold tolerance differed between populations but heat tolerance did not. Furthermore, juveniles demonstrated less tolerance for temperature extremes. When incubated at elevated temperatures, populations exhibited higher plasticity in cold tolerance compared to heat tolerance. Plasticity in heat tolerance was associated with a number of trade-offs. The data suggest that cold tolerance is locally adapted and phenotypically plastic while heat tolerance is conserved and phenotypically restricted in this species. My thesis highlights the need for the inclusion of various life stages, time scales, and biotic interactions in climate change research to better predict its impacts on fishes.Item Open Access Biological Constraints Determining Specialization in Canadian Plant-Pollinator Communities(2018-04-16) Villalobos, Soraya; Vamosi, Jana C.; Cartar, Ralph; Kevan, Peter G.; Johnson, Steig E.; Samuel, Marcus A.The overall objective of the research reported in this dissertation was to investigate biological factors underlying ecological specialization in Canadian plant-pollinator communities. Using a combination of fieldwork and the analysis of previously collected data, my research determined that landscape degradation led to observed local-scale differences in the prevalence of ecologically specialized clades of plants and pollinators in Canadian ecosystems. Through ecological and phylogenetic community analysis, I found that the alteration in community composition increases the prevalence of zygomorphic clades in the more degraded zones. Thus, plant community composition in disturbed areas favours the persistence of ecologically specialized groups (notably nitrogen fixers) that may enhance soil conditions. The prevalence of particular clades of pollinators in the two different habitats across Canada is partly due to the environmental tolerances of certain pollinator clades. Bombus clade comprised a higher proportion of prairie bees, whereas assemblages in Garry oak sites exhibited higher representation from solitary bees (e.g., Osmia, Andrena, Ceratina). Likewise, pollinator traits associated with areas that had more precipitations was soil nesting and traits related to areas that exhibited high temperatures were cavity-nesting. I identified specific cases of reciprocal specialization in plant-pollinator interactions as well as selective environmental occupancy of ecologically specialized clades. These findings can inform conservation efforts to maintain adequate pollination services to plant communities. Although disturbance interactions remained consistent in the number of reciprocal specialization cases, I hypothesize plant-pollinator interactions in prairie grassland systems in Alberta exhibit more interesting cases of specialization than previously thought.Item Open Access Diversification in Monkeyflowers: An Investigation of the Effects of Elevation and Floral Color in the Genus Mimulus(2014-01-05) Ogutcen, Ezgi; Hamper, Brooklyn; Vamosi, Jana C.The vast diversity of floral colours in many flowering plant families, paired with the observation of preferences among pollinators, suggests that floral colour may be involved in the process of speciation in flowering plants. While transitions in floral colour have been examined in numerous genera, we have very little information on the consequences of floral colour transitions to the evolutionary success of a clade. Overlaid upon these patterns is the possibility that certain floral colours are more prevalent in certain environments, with the causes of differential diversification being more directly determined by geographical distribution. Here we examine transition rates to anthocyanin + carotenoid rich (red/orange/fuschia) flowers and examine whether red/orange flowers are associated with differences in speciation and/or extinction rates in Mimulus. Because it has been suggested that reddish flowers are more prevalent at high elevation, we also examine the macroevolutionary evidence for this association and determine if there is evidence for differential diversification at high elevations. We find that, while red/orange clades have equivalent speciation rates, the trait state of reddish flowers reverts more rapidly to the nonreddish trait state. Moreover, there is evidence for high speciation rates at high elevation and no evidence for transition rates in floral colour to differ depending on elevation.Item Open Access Evaluating Strategies for the Restoration and Reestablishment of Native Grasslands in the Foothills Fescue Subregion in Southern Alberta(2020-09-16) Minc, Harriet; Goldblum, David; Bender, Darren J.; Vamosi, Jana C.Removal of invasive species within the Canadian shortgrass prairie is one of the greatest challenges to native grassland restoration. Invasive grass species are successful in this ecosystem because they are typically adapted to high grazing and trampling pressures, do not require fire for regeneration, and tolerate a wide range of climatic conditions. In the southern Alberta Foothills Fescue subregion, the common exotic species, Bromus inermis (smooth brome) and Poa pratensis (Kentucky bluegrass), are aggressive colonizers that spread quickly through rhizomes and are difficult to eradicate once established, allowing them to displace native grasses. Success of invasive species in this subregion is exacerbated by anthropogenic impacts, which include the alteration of fire regimes, extirpation of native grazers, and climate change. I investigated strategies for restoring a disturbed grassland by employing several restoration strategies in isolation and combination: mowing, plowing, herbicide application, carbon addition, and native seed addition. The experimental plots were monitored throughout the 2019 growing season. Within each plot, the total number of species, number of individuals per species, bare ground percentage, and aboveground biomass were quantified for each plot. At the end of the sampling period, soil samples were collected from each plot to test for differences in carbon, nitrates, pH, and salinity between treatments and control plots. The results showed the dominance of invasive species within the Foothills Fescue subregion with a majority presence of Kentucky bluegrass, smooth brome, and timothy (Phleum pratense). Through the application of the restoration treatment methods, plots that were plowed and seeded demonstrated the highest level of restorative success. However, low germination rates of planted seeds and seed predation from animals impacted overall biomass in some of the treatment types, suggesting that additional observation years are required for further assessment.Item Open Access The history and future of the rare, endemic plant species, Draba yukonensis (Yukon Draba)(2021-02-11) Jasper, Caroline; Vamosi, Jana C.; Musiani, Marco; Summers, MindiMany species in Canada remain poorly characterized regarding the projected impact of climate change. Here, I report my results from species distribution modeling for the rare, Yukon endemic plant, Draba yukonensis. Predicted change in range size in 2070 is an increase of 171375.1-184318.0 km2, which is surprising considering its limited known range. Overlap of predicted future and current ranges is 96.9-97.4%. Occurrence of protected areas in the predicted future range is 9.7-10.5%. It is possible that D. yukonensis represents a recently originated variety of a more common species that recently experienced polyploidization. I therefore performed phylogenetic analyses to elucidate relationships of D. yukonensis with other Draba species in the Yukon. I found that D. yukonensis is appropriately delineated as a Canadian endemic species and may be an allopolyploid of D. fladnizensis and D. lactea, or, likelier, is closely related to D. lactea. Overall, this work provides important predictions regarding where D. yukonensis could require interventions to aid its conservation.Item Open Access Impacts of Lake Physical Characteristics and the Presence of a Non-native Species on Diet Specialization in Threespine Stickleback (Gasterosteus aculeatus)(2018-09-21) Curley, Douglas Taylor; Vamosi, Steven M.; Vamosi, Jana C.; Galpern, Paul; Wasmuth, James D.The diet and dietary morphological adaptations of populations have been shown to be influenced by both the physical characteristics of their habitat and the presence of non-native species. In this study, I assessed how diet varies within and among populations of threespine stickleback (Gasterosteus aculeatus) in lakes with varying bathymetry in southwestern British Columbia. These lakes also differed in whether they contained the invasive signal crayfish (Pacifastacus leniusculus). Diet was evaluated through gut content analysis. I also investigated how morphology differs between these populations, as morphology has been shown to be linked to diet in stickleback. Diet data did not reveal any significant differences in diet among populations. However, morphology data did reveal significant differences among lakes and between crayfish conditions. The data suggest that diets higher in benthic invertebrates are associated with lakes with more littoral area and with the presence of signal crayfish.Item Open Access Molecular investigation of stalk formation and growth rates in Didymosphenia geminata(2018-04-02) Larsen, Krista Maria; Jackson, Leland J.; Rogers, Sean M.; Vamosi, Jana C.Didymosphenia geminata, a freshwater diatom, can produce thick benthic mats of stalk material. The cause of excess stalk formation is proposed to be low soluble reactive phosphorus (SRP) concentrations or a mat-forming genetic variant. Molecular studies on D. geminata are few, partly due to the lack of a reliable DNA extraction technique for the diatom, but have the ability to elucidate the drivers of mat formation. Specifically, comparison of gene expression between mat and non-mat-forming sites using reference genomes, may reveal underlying mechanisms behind growth and stalk formation. The objectives of this study were to: 1) identify gene products, expressed only at a mat or non-mat-forming site in Alberta (AB), involved in cell division or stalk formation from the reference genomes of P. tricornutum, T. pseudonana and C. crescentus; 2) compare SRP and growth rate, using frequency of dividing cells (FDC), between a mat-forming and non-mat-forming site; 3) compare FDC between multiple mat-forming sites in AB and British Columbia (BC); and 4) compare the quantity and quality of DNA obtained from mat-forming D. geminata using various preservation buffers, storage temperatures and extraction methods, including organic extraction, the Qiagen DNeasy® Plant Mini Kit, and a version of the kit procedure modified for D. geminata. Sixty-six putative gene products from the reference genomes were expressed only in the mat-forming sample, while 172 were expressed only in the non-mat-forming sample. FDC and SRP were higher at the non-mat-forming site, with no significant difference between FDC in AB and BC. Collectively, these results support previous findings that D. geminata forms excess stalk material under low SRP and increases cell division under higher SRP. However, an anomalous observation of mat formation at a site with 0.00986 mg/L SRP indicates stalk formation may be influenced by additional factors. In addition, the results of this study indicate that DNA extracted from samples stored in 95% EtOH at -80°C, using the modified kit method, had the best combination of quantity and quality.Item Open Access Phenological responses to climate in the Alberta native flora: Herbarium specimens reveal differential responsiveness between species in mesic and xeric habitats(2019-03-01) Porto, Cassiano; Vamosi, Jana C.; Goldblum, David; Theodor, Jessica M.; Yeaman, Sam; Quinney, Annie E.The field of phenology focuses on investigating the timing of biological events and phases of life cycles. In the face of projected and ongoing climate change, there is a growing interest in detecting the effects of climate change on plant phenology. This research focuses on using herbarium specimens to examine whether 14 native plant species in Alberta have adjusted to changes in temperature and precipitation over the past century. I hypothesize that the soil moisture to which plants are exposed might affect their phenological responses and investigate: if herbaria collections contain evidence of phenological responses to climate in species of the Alberta flora, and if the responses are dependent on the typical moisture regime of their habitat. Plants from mesic and xeric habitats are compared in terms of phenological responses to air temperature and precipitation. The taxonomic relationships between the species were taken into account, by selecting a total of 14 species representing seven different angiosperm orders (one pair of species for each order). For each selected species, the preserved specimens available at three major Albertan herbaria collections were included in the study, if showing more than 50% of flower buds in anthesis (defined as peak flowering). The peak flowering date of each specimen, combined with the average temperature (or total precipitation) of the species’ mean flowering month and the three months prior, allowed the use of a regression model for the estimation of a species’ phenological responsiveness. The linear multiple regression analysis has revealed a significant responsiveness to temperature for six species from xeric habitats and one species from mesic habitats. My results suggest that species from xeric habitats have an average phenological responsiveness to temperature significantly more pronounced than species from mesic habitats. This tendency might be explained by the thermal properties of mesic habitats. The results indicate that for some species there is a set of environmental cues, as opposed to only one parameter, that governs flowering timing. The elucidation of the ecological implications involving plants phenological responses is key for the development of effective ecosystem conservation programs in the context of global climate change.Item Open Access Pollination of Rubus arcticus L. in Alberta: microclimate effects on pollinator availability and the role of pollen limitation on fruit set(2018-05-22) Burns, Cole; Vamosi, Jana C.; Cartar, Ralph Victor; Longair, Robert W.Rubus arcticus Linnaeus is a widespread plant species that likely experiences changes in pollinator visitation and fruit production with microclimate. A pollen supplementation experiment with open controls, pure-selfed and outcross supplemented treatments was used to determine if R. arcticus fruit production is limited in the quantity of pollen deposited. This experiment was then complemented by a pollen tube analysis to determine the importance of pollen quality. To determine the effects of microclimate on R. arcticus pollinator availability and foraging behavior, pollinator surveys were conducted using time-lapse photography which was accompanied by micrometeorological monitoring with measurements from humidity/temperature loggers, an anemometer for wind speed, and hemispherical photography for solar irradiance. The results provide evidence that fruit production in R. arcticus can be extremely low in regions that are at the southern parts of its range, but this low fruit production does not necessarily reflect pollen limitation. The dominant pollinators of the study population were syrphid flies, which exhibited visitation frequencies that were influenced by temperature and humidityItem Open Access Relationships between nitrogen, phosphorus and diel dissolved oxygen cycles in the Bow River, Calgary, Alberta before and after a century-scale flood(2018-06-28) Singer, Jarvis Garry; Jackson, Leland J.; Chambers, Patricia A.; Vamosi, Jana C.High nutrient loading to rivers increases aquatic plant and algal growth resulting in low dissolved oxygen (DO) concentrations. The overall objective of this thesis was to examine the relationship of nitrogen (N) and phosphorus (P) in diel DO cycles induced by periphyton and macrophyte photosynthesis and respiration in the Bow River. I tested periphyton and macrophyte nutrient limitation status directly using fertilization experiments at multiple locations within Calgary’s wastewater treatment plant (WWTP) effluent affected urban footprint. My results show that immediately after the 2013 flooding, primary production was limited by P (periphyton) or N+P (macrophytes). I investigated empirical relationships between periphyton, macrophytes and diel dissolved oxygen concentrations before and after a 1 in 100-year flooding event. The near complete removal of macrophytes was associated with only a transient decrease in the magnitude of diel DO oscillations at sites downstream of WWTPs.Item Open Access Toxic cyanobacteria in relation to sulfate, molybdenum, nitrogen and phosphorus in Alberta's shallow prairie lakes(2018-10-19) Anderson, Susan Marie; Jackson, Leland J.; Kinniburgh, David W.; Vamosi, Steven M.; Vamosi, Jana C.Cyanobacteria are characteristic of poor global water quality. They create a public health concern and threaten biodiversity, particularly when they produce toxins such as microcystins. It is poorly understood why cyanobacteria produce microcystins, or how cyanobacteria in shallow prairie lakes will respond to increased salinity under changing climate. To study the effects of variable sulfate concentrations on cyanobacteria and to elucidate environmental patterns of microcystin production, I sampled 25 shallow lakes over four months for total nitrogen (TN), dissolved inorganic nitrogen (DIN), total phosphorus (TP), soluble reactive phosphorus (SRP), sulfate, molybdenum, microcystins, and the cyanobacteria-specific pigments canthaxanthin, myxoxanthophyll and echinenone. There was a negative relationship between cyanobacteria pigment and sulfate, and a positive relationship between cyanobacteria pigment and molybdenum and total nitrogen. Microcystins positively correlated with cyanobacteria pigment and turbidity. When microcystin samples above 10 µg·L-1 were removed, microcystins correlated with TN:TP in June and July. My results suggest that increasing sulfate leads to less cyanobacteria pigment. With the prairies expected to get hotter and dryer in the future, shallow prairie lakes are likely to see less cyanobacteria as they increase in salinity. My results also indicate that higher cyanobacteria pigments correlate with higher microcystins. Although low TN:TP can lead to high microcystins, low TN:TP is not enough to differentiate between high and low microcystins. No thresholds were found in either analysis, meaning there was no evidence for a tipping point where sulfate limits cyanobacteria nor the existence of environmental triggers associated with microcystin production over the season.