PRISM :: Browsing by Author "Vamosi, Jana"

Browsing by Author "Vamosi, Jana"

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Open Access
Accurate Early Prediction of Leafy Spurge Invasion Using Species Distribution Models (SDMs) in Alberta
(2024-08-16) Zardecki, Natalie Ruth; Vamosi, Jana; McLean, Mary Ann; Ruckstuhl, Kathreen
Globalization has resulted in the development of new ecological communities with the introduction of new species to native habitats. While some introduced species benefit their surrounding environments or leave insignificant impacts, others are invasive and decrease an area’s ecological stability. One such invasive plant species, commonly known as Leafy spurge, is increasing in concern to Alberta’s grasslands and agricultural industries. The plant produces a noxious latex that is toxic to livestock and aggressively outcompetes surrounding vegetation. Once established in an environment, Leafy spurge becomes resistant to control mechanisms, requiring multiple treatments to reduce patch sizes. To better predict Leafy spurge’s invasion status in Alberta, I explored the development of Species Distribution Models (SDMs) using BIOMOD2 and MaxENT approaches to compare their predictive abilities using bioclimatic and ecological variables and then tested the accuracy of the models with independent data from field surveys. Results indicated that BIOMOD2 models are more accurate due to the ensemble-modelling approach, which had evaluation scores consistently higher than those of MaxENT, and the inclusion of variables relating to establishment and dispersal contributed more to model accuracy than bioclimatic variables. With the use of this SDM for Leafy spurge invasion in Alberta, mitigating controls can be effectively implemented to limit its spread and predict at-risk areas in need of greater surveillance.
Open Access
Bumble bee use of heterogeneous mountain habitats: A landscape genomic approach
(2023-05-09) Clake, Danielle Jessica; Galpern, Paul; Rogers, Sean; Cartar, Ralph; Vamosi, Jana
Land use modifications and climate change are two of the major factors behind global biodiversity losses. The specific impacts and long-term implications of these changes have yet to be understood for many species. Bumble bees (Bombus sp.) are an important group of pollinators, especially in temperate and montane regions where they are relatively abundant. They are also facing global declines and range shifts. In this thesis I pose several questions investigating the relationship between bumble bees and mountain landscapes. I first ask whether bumble bee abundance and species richness are positively or negatively associated with measures of landscape fragmentation. I then demonstrate patterns of genetic and phenotypic diversity and differentiation in the high elevation taxa Bombus lapponicus sylvicola and assess hypotheses about mechanisms that could be causing the differentiation I observe. Lastly, I test whether gene flow in four bumble bee taxa has been restricted between habitats of differing elevations. To answer these questions, I sampled 22 species of bumble bees from 69 sites across a 40,000 km2 geographic range, where sites were selected to minimize correlations between variables of interest. I extracted DNA from 745 individuals of four different taxa, and used SNPs derived from ddRAD libraries to measure genetic diversity and gene flow. In this thesis I report higher abundance and species richness of bumble bees in locations where surrounding land cover has higher levels of complementation between nesting and foraging habitats, but that abundance and species richness decrease with other measures of fragmentation. I describe a new cryptic subspecies of B. sylvicola based on genetic and phenotypic diversity, and present evidence that it may have differentiated under conditions of gene flow based on adaptation to cold minimum temperatures. Finally, I present evidence that high elevation taxa appear to be able to exchange genes freely across elevations, while taxa associated with lower elevations display patterns of reduced gene flow across elevations. These findings have important implications for the conservation of montane bumble bee species and provide several avenues for future study and investigation.
Open Access
The Colourful World of Platyrrhine Monkeys: Skin Colour Variation and Its Potential Role in Communication
(2022-09) Alves Antonio Moreira Pacheco, Lais; Melin, Amanda; Higham, James; Pavelka, Mary; Notman, Hugh; Smith, Andrew; Vamosi, Jana
Understanding the evolution of human communication has been a longstanding goal of anthropologists and has spurred many lines of research. Studying our closest living relatives, the non-human primates (NHPs), provides an opportunity to better understand human communication, by placing it in a comparative context. Among NHPs, use of colour signals is common and widely distributed across the Order. Catarrhines have trichromatic colour vision and exposed skin colouration plays an important role in their interactions. In platyrrhines, exposed skin is less common, but some genera have widely exposed body regions, suggesting that skin colouration might also be used for communication. Intriguingly, platyrrhines have polymorphic colour vision, in which some individuals are dichromats while others are trichromats. This polymorphism may affect signal perception by conspecifics and shape some aspects of communication. However, we currently lack studies measuring colour (hue, saturation, chroma) variation in their skin. In this thesis, I provide several studies that seek to explore the potential for colour signals in platyrrhines. I provide the first analysis of the distribution and evolution of facial skin exposure and colour in platyrrhines in Chapter 2. I then report in Chapter 3 variation in facial skin colour of golden lion tamarins (Leontopithecus rosalia) in the context of breeding status, reproductive condition, and age. In Chapter 4, I investigate if female genital skin colour of two species of wild tamarins [saddleback (Leontocebus weddelli) and emperor tamarins (Saguinus imperator)] vary between developmental classes. Finally, I study the hypertrophied and pendulous clitoris of female black-handed spider monkeys (Ateles geoffroyi) and investigate if its colour and shape varies within and between individuals. My results suggest that among platyrrhines there is extensive variation in skin exposure and colouration and that colour seems to be linked to breeding status, reproductive condition and age in some species, and colour variation occurs within and between individuals. These results show potential for convergence in some functions of bare-skin signaling in catarrhine primates. My Doctoral Thesis makes contributions to the understanding of primate communication by adding new comparative data to illuminate the selective pressures shaping the sensory and communication systems across our order.
Open Access
Conservation genomics of the endangered Banff Springs Snail (Physella johnsoni) using Pool-seq
(2019-01-07) Stanford, Brenna; Rogers, Sean; Lepitzki, Dwayne; Vamosi, Jana
Understanding how species persist and adapt to local habitats is a fundamental question for species of conservation concern. Located in Banff National Park, the endangered snail, Physella johnsoni, inhabits seven highly specialized thermal springs. P. johnsoni undergo yearly population bottlenecks with minimal to no dispersal among springs. The consequences of these processes on genetic population structure are unknown. To investigate effects of habitat and life history on P. johnsoni’s genome and to test the hypothesis of a single panmictic population, I collected 20 to 40 snails/population for P. johnsoni and a closely related snail, P. gyrina, in adjacent, non-thermal water. Using whole genome pooled-sequencing, millions of single nucleotide polymorphisms were captured. These genetic variants resolved significant genetic divergence between P. johnsoni and P. gyrina. In addition, I detected distinct genetic clusters and reduced nucleotide diversity within each spring, indicative of strong micro-geographical population structure and suggestive of a role for genetic drift. These results suggest that P. johnsoni from each spring represent a distinct genetic unit, which has conservation implications for the designation of designatable unit status under COSEWIC, and where mixing of snails may reduce the consequences of genetic drift.
Open Access
Creating digital collections of biological specimens: Lessons for teaching and learning
(2021-08-11) Ruddock, Kathryn; Summers, Mindi; Vamosi, Jana
University of Calgary Libraries has partnered with faculty in Biological Sciences since 2016 to digitize, describe and share herbarium and invertebrate specimens through digital collections as a resource for students. These collections are used by students and are created in partnership with students as part of course assignments. COVID-19 and online instruction made the collection and training resources even more valuable to our learners than we originally envisioned. Join us to learn how we created these collections, uses for the digital objects in teaching and learning, and limitations of the digital collection when the physical specimen is not accessible.
Open Access
Development of Best Strategies for the Control of Butomus umbellatus L. (Flowering Rush) In Alberta
(2018-01-25) Cahoon, Lisa; Vamosi, Jana; Jackson, Leland; Vamosi, Steven; Blue, Gwendolyn
The emergent aquatic perennial, Butomus umbellatus L. is a prohibited noxious weed in Alberta. In this thesis I provide (1) the first comprehensive review on its phenology and cytotype in Alberta; (2) an examination of the effect of cytotype on propagation means and (3) an experimental test of different control methods in two infested Alberta lakes. One of the findings of this study is that a full understanding of the propagation of this species is complicated because there are two cytotypes: fertile diploids and sterile triploids. I describe in this thesis how most populations of B. umbellatus in Alberta appear to be the diploid cytotype, except for a triploid population in Innisfail. My studies found that in diploid plants, sexual reproduction is not the primary means of spread. My results also indicate that all control methods currently in use are equally unsuccessful, largely because B. umbellatus invests so heavily in vegetative reproduction that removing the entire rhizome is difficult. Because of this life history feature, B. umbellatus will likely be most effectively controlled by quickly recognizing new populations and removing all plant material. While revegetation of a reclaimed area with indigenous plants could prove beneficial, my results indicated that B. umbellatus quickly reclaims sites that have been replanted with native species.
Open Access
Effects of Landscape Age and Salinity on Plant Community Composition and Productivity in Opportunistic and Constructed Wetlands in the Athabasca Oil Sands Region, Alberta
(2023-08) Mombourquette, Ashlee Dawn; Ciborowski, Jan; Chasmer, Laura; Hornung, Jon; Vamosi, Jana; Galpern, Paul
Wetlands comprise 65% of the Athabasca Oil Sands Region (AOSR) surface mineable area and thus support diverse flora (approximately 400 species in Alberta). Due to increased anthropogenic land disturbance activities such as bitumen extraction, reclamation of surface mineable areas will also increase. The resulting reclaimed areas will tend to be sodium-enriched compared to pre-disturbance landscapes. In this thesis, forty young (<40 years old) stratified-randomly selected wetlands were sampled on reclaimed landscapes at Syncrude’s Mildred Lake lease and from reference wetlands in adjacent areas in the AOSR to determine how salinity and age influence the vegetation community composition, and the biomass of six dominant wetland plant species (Carex aquatilis, Calamagrostis canadensis, Carex atherodes, Carex utriculata, Schoenoplectus tabernaemontani, and Typha latifolia) found on reclaimed and reference landscapes. Wetland vegetation communities on reclaimed landscapes differed from those on reference landscapes; however, landscape type had no impact on the biomass of the dominant plant species. Vegetation communities varied along a salinity gradient; species richness was negatively associated with salinity, and vegetative species abundance (percent cover) was lowest in freshwater wetlands and highest in moderately brackish wetlands. Species richness did not differ among wetland classes. However, vegetative species abundance was significantly different among age classes. The biomass produced by each dominant species did not vary with respect to a gradient of salinity or among wetlands of different age classes. These findings may provide a useful frame of reference against which to compare vegetation communities that may be observed in wetlands forming on reclaimed landscapes.
Open Access
Extinction Risk Escalates in the Tropics
(Public Library of Science, 2008) Vamosi, Jana; Vamosi, Steven M.
Open Access
Forest Cover Influences the Predictions Made by Species Distribution Models: A Case Study of American hazelnut (Corylus americana)
(2024-10-11) Cramb, Nicholas; Vamosi, Jana; Dawson, Andria; Galpern, Paul; Yeaman, Samuel
Species distribution models can be used to predict climate impacts on biodiversity and guide conservation efforts. However, they may not fully represent biological reality when they entirely rely on climate variables alone and neglect biological interactions. My research objective is to test if including forest cover as a quantitative proxy for shrub-canopy interactions improves the predictive ability of species distribution models. My work focuses on American hazelnut (Corylus americana) as a case-study to test this framework. American hazelnut is a good candidate species because it is widely distributed throughout the eastern temperate and northern forests of North America and is likely to interact with the full gradient of 0 to 100% forest cover. The species remains understudied regarding the determinants of its distribution, despite an excellent fossil pollen record. This project used the hazelnut fossil pollen record to model the influence of canopy cover on distribution through time and to test whether hazelnut niche has been stable over time. For distribution models of American hazelnut, I found no difference in model performance when land cover variables are included at a continental extent. However, at a regional extent I found significant increases in model performance when forest cover was included. These findings suggest that land cover can more precisely define where species habitat exists at a local level compared to climate variables alone. Distribution models developed using fossil pollen occurrences and climate simulations indicate that hazelnut has maintained a consistent niche space over the past 11,000 years before present. However, the limitations of fossil pollen data created less certainty in these results. Future work involves testing this framework on additional species to determine if these patterns are consistent across woody taxa, as well as testing if land cover datasets that are more categorically resolved and include human impacts are able to improve distribution models.
Open Access
Genetics and evolution of ultraviolet reflectance in flowers
(2018-01-25) Liu, Yan; Vamosi, Jana; Samuel, Marcus; Ro, Dae-Kyun; Melin, Amanda; Caruso, Christina
Many flowers have ultraviolet (UV) reflectance patterns, which are invisible to humans but visible to pollinators, such as bumblebees and hummingbirds. In bees and hummingbirds, photoreceptors are sensitive to UV wavelengths, and it is therefore necessary to incorporate this variable to model pollinators’ perception and assess floral UV evolution. In this thesis, I explore micro- and macroevolutionary patterns in floral UV patterns, specifically concentrating on the effect of this phenotype on pollinators. I first explore the ways in which UV patterns can be measured and characterized, as well as explore the underlying basis of UV patterning in flowers. By gathering UV reflectance data (between 300 to 400nm) on 150 species, I found evidence that the phylogenetic distribution of UV trait disparity is consistent with a stabilizing selection model of evolution, but the magnitude of stabilizing selection varies with geography and pollinator syndrome. Mimulus species have become key model species for investigating the genetics of floral adaptations, in part because it is tremendous diversity in floral phenotypes. I firstly estimate genetic diversity in six populations in Alberta and British Columbia. Historical contingency (via geographic and bioclimatic events) provides the evidence of restricted gene flow. Variance in phenotypes depends not only on allelic interactions but also on environmental factors. Variation and heritability of the floral UV reflectance are further explored with experimental interspecific crosses between Mimulus guttatus and Mimulus luteus. By recoding 12 floral traits throughout the parental to F4 generations, I find that phenotypic covariance is strongest between UV reflectance and other floral traits, lending evidence to the idea that UV reflectance in flowers evolves along with other floral traits as a response to selection from pollinators. My research has implications for forecasting plant adaptation through hybridization and polyploidization, which may occur in concert with the evolution of plant-pollinator relationships.
Open Access
Heterogeneity in pollinator composition and the effects on selection for floral display of plectritis congesta
(2012) Adderley, Lorraine Johnston; Vamosi, Jana
The plant-pollinator mutualism can be disrupted in isolated populations. This relation also critically affects directional selection on floral traits. Isolated plant populations may attract fewer and less diverse pollinators, and plants may compete for pollination within the population and with other co-flowering plant species , possibly selecting for increased number of flowers in the floral display. In this thesis, I characterized the major pollinators of Plectritis congesta ( or Sea blush), to study the effects of isolation on the Gulflslands and Vancouver Island. I found that: (1) site connectivity is a major determinant of the pollinator assemblage; (2) population density is correlated with floral display, visitation rates, and possibly pollinator assemblage, whereas competition from co-flowering species is not; and (3) both floral display and geographical elements that control pollinator abundance and composition influence the potential for selfing, and pollinator composition could impose selection for increased floral display in isolated populations.
Open Access
Landscape composition and configuration affect nest founding but not success of bumble bee colonies in agroecosystems in the Lower Mainland of British Columbia, Canada.
(2021-04-27) Kwafo, Richard; Galpern, Paul; Cartar, Ralph; Vamosi, Jana; Post, John
Landscape structure influenced by land-use is likely to affect pollinator demography. Using naturally colonized nest boxes placed at 27 sites in the Lower Mainland of British Columbia, I assessed demographic responses of bumble bees to the availability of resources as inferred from landscape structure (i.e., landscape composition and configuration), and examined the spatial scale that best explained responses to the landscape. I used mixed model regression analysis to model the influence of semi-natural habitat, beneficial agriculture, suburban cover, and habitat edge density, all measured in six radii (250 m - 2500 m) around colonies, on nest founding and success of bumble bee colonies. Semi-natural habitat had no relationship with nest founding and colony success. Nest founding decreased in surroundings with more “beneficial agriculture” cover (i.e., mass flowering berry crops), however, nest founding increased at locations with more edge habitats. Higher amount of suburban cover decreased nest founding. Nest founding was best explained by the landscape at a 1500 m radius around the nest, however, there was no evidence of colony success responding to the landscape at any spatial scale. I conclude that beneficial agriculture and suburban cover had negative consequences for nest founding in bumble bee populations within my study landscape. Edge habitats seemed to attract more bumble bee queens to nest and may maintain bee populations while serving as sources of wild bumble bee pollinators, who might forage within nearby commercial blueberry crops to improve crop yield.
Open Access
Lodgepole pine linkage map reveals patterns of genomic clustering of locally adaptive loci
(2023-03-17) McDonald, Tegan Krista; Yeaman, Samuel; Rogers, Sean; Possant, Jocelyn; Vamosi, Jana; De koning, Jason
Adaptation to heterogeneous local conditions is near ubiquitous throughout the tree of life. Climate adaption requires a complex system of trade-offs and multifaceted responses, and while the evolutionary theory is reasonably well developed and empirical evidence abundant, the genetic basis of local adaptation is poorly understood for complex traits outside of model organisms. Conifers demonstrate an immense capacity for local adaptation over a wide range of climatic and ecological conditions, and although they are ecologically and economically important, the size and complexities of conifer genomes have limited our ability to study the genetic basis of such adaptation as reference resources are scarce. Here, I have constructed a linkage map for lodgepole pine to examine the patterns of linkage disequilibrium and physical linkage amongst putative adaptive loci identified by Genotype-Environment Associations (GEAs) to 19 climate related variables. We find the high amounts of linkage disequilibrium (LD) observed amongst top-candidate genes are largely attributable to physical linkage, yet are generally distinct loci with some cases potentially indicative of neutral genetic hitchhikers. The context provided by the linkage map to signals of adaptation reveals an intriguing pattern of clustering of loci and reuse of genomic regions in response to distinct, but related, environment factors. These patterns suggest evolution of both clustered and diffuse architectures underlying climate adaptation in lodgepole pine.
Open Access
Pollination Responses to Introduced Plants and an Elevation Gradient in Camas Dominated Wet Meadows
(2024-01-01) Rampton, Rowan W.; Galpern, Paul; Vamosi, Jana; Summers, Mindi
Global change is driving declines in insect biodiversity, with widespread consequences for ecosystem function. Climate change and invasive species are key global change factors, but the ways in which they alter pollination are poorly understood in many systems. Camas meadows occur in the southwestern-most areas of Canada, where they support high floral and pollinator diversity, yet we know little about the pollination ecology of these meadows, let alone how they are impacted by aspects of global change. My objectives in this thesis were to evaluate evidence that camas meadows are experiencing impacts related to climate change and plant invasions. I used a pollen limitation experiment conducted across an elevation gradient to evaluate whether variation in climate generates phenological asynchrony between camas and its pollinators, and used plant-pollinator network analysis to examine whether introduced plants were driving changes in pollination networks. I found that there was no evidence for phenological asynchrony, though camas reproduction was slightly limited by pollen at low elevations, while overall seed production declined as camas approached its elevational limit. Introduced species did not alter network structure, but when removed from networks they had come to dominate, networks were less able to resist further species loss. This suggests that if maintaining pollination is desired, invasive species management decisions should consider the risks associated with losing the floral resources they seek to control. My results describe a system which in its current state, appears robust to the aspects of global change examined (i.e., phenological disturbance and plant invasion) but may be sensitive to further disruption, particularly the removal of abundant introduced plants that pollinators have come to rely upon.
Open Access
Pollinator Movement and Pollen Transfer in Hybrid Seed Canola
(2017) Waytes, Riley; Cartar, Ralph; Hoover, Shelley; Vamosi, Jana; Barclay, Robert; Owen, Robin
Production of hybrid seed canola requires the transfer of pollen from hermaphroditic (‘male’) to male-sterile (‘female’) plants, facilitated by managed pollinators (honey and leafcutter bees) and wild pollinators. I assessed pollinators in fields of hybrid seed canola located in Southern Alberta to determine what behaviours and conditions could enhance pollen transfer between male and female plants. I found that managed species were the most common pollinators, that all pollinators exhibited floral constancy to morph (male or female), and that pollinator type, time on flower, pollen on body, and flower of origin influenced pollination effectiveness. Pollinator movement between male and female flowers was positively affected by densities of conspecific pollinators, taxon richness, and relative floral profit. While hybrid seed canola morphs are sexually dimorphic, sufficient quantities of managed pollinators should reduce floral constancy. Wild pollinators can contribute to cross-pollination indirectly by increasing managed pollinator movement via increased diversity.
Open Access
Pollinators visit related plant species across 29 plant– pollinator networks
(John Wiley & Sons, 2014-06) Vamosi, Jana; Moray, Clea M.; Garcha, Navdeep K.; Chamberlain, Scott A.; Mooers, Arne Ø.
Open Access
Population divergence and candidate signatures of natural selection in alpine and lowland ecotypes of the allotetrapoloid plant, Anemone multifida (Ranunculaceae)
(2012-09-06) McEwen, Jamie; Rogers, Sean; Vamosi, Jana
Adaptation plays a central role in population divergence and speciation. Studying the evolutionary history of populations due to neutral evolutionary processes and the effects of natural selection enables the identification of genes under natural selection in the wild. In this thesis, I conducted a genome scan to elucidate candidate signatures of natural selection in alpine and lowland ecotypes of the allopolyploid plant, Anemone multifida. I found numerous signatures of divergent natural selection between alpine and lowland populations and between alpine populations, but natural selection appeared strongest in alpine environments. These results are consistent with findings in diploid species, but the neutral evolutionary structure of the polyploid A. multifida showed complex patterns of differentiation. Overall, these results indicate divergent natural selection has generated adaptation to alpine and lowland environments despite complex evolutionary history.
Open Access
Resource Allocation and Translocation to Sexual Reproduction and Clonal Growth in the Rewardless Orchid Cypripedium parviflorum
(2017) Sawich, Lauren Suzanne; Harder, Lawrence; Barclay, Robert; Vamosi, Jana; Goldblum, David
Resource allocation trade-offs may occur between life-history traits in plants, including sexual reproduction and clonal growth. Pollination (fruit) failure may relax trade-offs, and excess resources stored in rhizomes may increase clonal growth. Two varieties of Cypripedium parviflorum, a rewardless orchid, responded to pollination success or failure with resource allocation (within ramets) and translocation (between ramets) appropriate to their respective life histories. Ramets financed their own fruits and had greater rhizome allocation in response to pollination failure. Var. makasin had low fruit set (~19.1%), prioritized fruit production, and translocated resources to sister ramets developing fruits (ramet and genet trade-offs). Var. pubescens had high fruit set (~45.1%), allocated more resources to leaves, which gained mass when developing fruits, and did not translocate resources (mitigated ramet trade-offs and no genet trade-offs). Clonality declined with increasing fruit set when fruit set was poor (i.e., var. makasin) and in low-density and large populations.
Open Access
Restoration for Wild Bee Community Recovery in the Prairie Pothole Region
(2021-05-03) Purvis, Emily Elizabeth Nan; Galpern, Paul; Vamosi, Jana; Summers, Mindi
Agricultural intensification is a widespread driver of global pollinator decline, which can subsequently threaten the ecosystem services provided to flowering food crops and wild vegetation species. In North America's Prairie Pothole Region, wetlands surrounded by grassland were once abundant on the landscape, but now generally exist within a matrix of agriculture. I assessed whether restoration of these grassland-wetland complexes from cropland could be used as a tool for mitigating wild bee decline and monitored the development of bee nesting and food resources to establish the mechanisms that drive return to a restored habitat. My objective was to determine if restored communities could resemble a reference state (i.e. remnant grassland-wetland complexes) over a 25-year period. I also observed plant-pollinator interactions and used a model-based approach to determine which plant species supported the highest diversity of wild bees, with the objective of identifying beneficial flowering plants to include in future restorations designed to increase the availability of flowering plants. I found bee diversity increased following restoration and approximated reference sites after 1–4 years. Analyses for bumble bees (Bombus spp.) and other bee species separately demonstrated that the latter group was slower to recover, and resembled reference sites after around 5–10 years. Floral diversity also increased following restoration from cropland but remained slightly lower than reference sites through time. Flower species composition was most important for explaining bee species composition, while time since restoration was comparatively less important. From plant-pollinator interactions, I identified 16 plant species from eight families that supported the highest diversity of bees, including Bombus terricola, a species at risk. In general, Fabaceae species were more popular with bumble bees, while a greater variety of plant families supported non-Bombus bees. My results highlight a potential pathway to improve restoration for wild bee conservation in this region by including specific flowering plants. They also underscore the utility of restored grassland-wetland complexes for providing food and nesting resources to bees within agriculturally dominated landscapes and suggest that restoration can recover wild bee communities to a reference state.
Open Access
Scaling of Density-Dependent Reproduction in Bee-Pollinated Forbs of Logged Forests
(2015-12-16) Johnson, Sarah A.; Cartar, Ralph; Vamosi, Jana; Ruckstuhl, Kathreen; Galpern, Paul; Goldblum, David
Plant reproduction can be impacted by a variety of influences at a range of spatial scales. In the face of accelerating anthropogenic habitat disturbance, it is worth understanding how communities function within highly altered landscapes. I examined how seed size and number varied for nine species of understory forb within logged foothills forests of southern Alberta. I examined local relationships between reproductive output and floral neighbourhood, bee abundance, and habitat variation, and how these might be modified along a gradient of landscape-scale clearcut logging. I found that local variables best explained plant seed production, and heterospecifics were generally more beneficial than expected. Further, logging in the landscape modified local interactions above a threshold point of approximately 50% logging in a 1.77 km^2 area, predominantly for more habitat-specialized species. These results have implications for forest management, and for the importance of testing for interactions between explanatory variables, even across spatial scales.