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This paper examines the demand for hockey game trips among metropolitan and nonmetropolitan residents of Alberta, Canada. Using data on both revealed and stated preference game-trip behavior from a telephone survey conducted throughout Alberta, we estimate the effect of ticket prices, team quality, arena amenities, and capacity on the latent demand for National Hockey League hockey games. We find that lower ticket prices, higher team quality, and additional capacity encourage attendance. In the status quo scenario, consumer surplus per game is $50 for those who had attended hockey games and about 50% less for those who had not attended games. Exploiting the stated preference data, we develop a number of other consumer surplus estimates. We also include travel costs in the estimation of the demand function and estimate the full value of the game trip considering both ticket prices and travel costs. Sold-out arenas in Calgary and Edmonton generate annual consumption benefits of $40 and $35 million when only ticket prices are used to calculate consumer surplus (i.e., excluding travel costs). Considering the full-price consumer surplus for the Calgary Flames of $103 per game trip, the annual consumption benefits may be as high as $82 million. [ABSTRACT FROM AUTHOR]

Abstract. In our earlier studies of the supermarket industry in Edmonton, Alberta, we tested for predation in a spatial setting and found evidence which supported the predation hypothesis. In this paper we use data on the locations, entry, exit and market area populations of supermarkets in Edmonton to test whether the entry deterrence and timing-of-expansion implications of the reputation hypothesis are confirmed. We find that our time series data are consistent with entry's being deterred and with delayed opening of new supermarkets by the dominant established firm. [ABSTRACT FROM AUTHOR]

Please cite this paper as: Krauss et al. (2012) Respiratory tract versus cloacal sampling of migratory ducks for influenza A viruses: are both ends relevant? Influenza and Other Respiratory Viruses DOI: . Background Early studies in dabbling ducks showed that cloacal swabs yielded a larger number of avian influenza virus (AIV) isolates than did respiratory tract swabs. Historically, AIV surveillance has been performed by collecting cloacal or environmental fecal samples only. Highly pathogenic avian influenza H5N1 virus emerged in 1996 and replicated to higher titers in the respiratory rather than the gastrointestinal tract of ducks, prompting the collection of respiratory samples in addition to cloacal swabs from wild birds. Studies confirmed that some virus subtypes, especially H9 and highly pathogenic H5, are shed primarily through the respiratory tract and may not be detected in cloacal swabs. Objectives To examine prevalence and subtype differences for AIV isolates from cloacal or respiratory swabs of wild ducks and to determine whether individual respiratory tract samples should be included in AIV surveillance studies in wild birds. Methods Individual respiratory tract and cloacal swabs were collected from each of 1036 wild ducks in Alberta, Canada, during the month of August from 2007 to 2010 in an ongoing surveillance study. Virus isolation in eggs and subtype identification by antigenic and molecular methods were performed. Results and conclusions Respiratory tract and cloacal swabs yielded ten influenza virus HA subtypes representing 28 HA-NA combinations. Three HA-NA subtype combinations were found exclusively in respiratory tract samples. Only four HA subtypes (H1, H3, H4, and H7) were recovered from respiratory samples, but respiratory shedding was associated with the dominance of 1 year's subtype. Might respiratory shedding provide a risk assessment indicator? [ABSTRACT FROM AUTHOR]

Aim The spatial extent of western Canada’s current epidemic of mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae, Scolytinae), is increasing. The roles of the various dispersal processes acting as drivers of range expansion are poorly understood for most species. The aim of this paper is to characterize the movement patterns of the mountain pine beetle in areas where range expansion is occurring, in order to describe the fine-scale spatial dynamics of processes associated with mountain pine beetle range expansion. Location Three regions of Canada’s Rocky Mountains: Kicking Horse Pass, Yellowhead Pass and Pine Pass. Methods Data on locations of mountain pine beetle-attacked trees of predominantly lodgepole pine ( Pinus contorta var. latifolia) were obtained from annual fixed-wing aircraft surveys of forest health and helicopter-based GPS surveys of mountain pine beetle-damaged areas in British Columbia and Alberta. The annual (1999–2005) spatial extents of outbreak ranges were delineated from these data. Spatial analysis was conducted using the spatial–temporal analysis of moving polygons (STAMP), a recently developed pattern-based approach. Results We found that distant dispersal patterns (spot infestations) were most often associated with marginal increases in the areal size of mountain pine beetle range polygons. When the mountain pine beetle range size increased rapidly relative to the years examined, local dispersal patterns (adjacent infestation) were more common. In Pine Pass, long-range dispersal (> 2 km) markedly extended the north-east border of the mountain pine beetle range. In Yellowhead Pass and Kicking Horse Pass, the extension of the range occurred incrementally via ground-based spread. Main conclusions Dispersal of mountain pine beetle varies with geography as well as with host and beetle population dynamics. Although colonization is mediated by habitat connectivity, during periods of low overall habitat expansion, dispersal to new distant locations is common, whereas during periods of rapid invasion, locally connected spread is the dominant mode of dispersal. The propensity for long-range transport to establish new beetle populations, and thus to be considered a driver of range expansion, is likely to be determined by regional weather patterns, and influenced by local topography. We conclude that STAMP appears to be a useful approach for examining changes in biogeograpical ranges, with the potential to reveal both fine- and large-scale patterns. [ABSTRACT FROM AUTHOR]

Presents the minutes of the 36th annual general meeting of the Canadian Economics Association held on June 2, 2002 in the University of Calgary in Alberta. Report of the secretary-treasurer; 2002 election results; Nominations for 2003.

Unconformity‐related uranium (URU) deposits in the Athabasca Basin, Canada, include the highest grade, large tonnage deposits in the world. Recent studies of the Patterson Lake corridor uranium deposits suggest a deep heat source enhances hydrothermal fluid flow and incursion of basinal brines along brittlely reactivated ductile shear zones. However, the spatial extent of the ore systems and lower crustal features capable of driving the hydrothermal cells remained largely unresolved. Three‐dimensional electrical conductivity models derived from inversion of magnetotelluric data and coincident gravity modeling identified a voluminous conductivity anomaly and corresponding gravity low related to a belt of high‐heat producing intrusions that dips below the deposit. Shallow conductive bodies are identified below the deposits and similarly prospective corridors. The volume and location of the intrusive bodies may have provided a source of radiogenic heat that helped drive remobilization of fluids along reactivated structures, redefining the spatial extent of URU systems. Plain Language Summary: The western Athabasca Basin, straddling the border of Saskatchewan and Alberta in Canada, is home to some of the highest‐grade, large tonnage uranium deposits in the world. Recent studies have suggested a spatial connection between uranium ore systems that are found near the earth's surface and geological processes occurring deep within the crust. However, the processes connecting the lower crust to these shallow deposits is poorly understood. This study used 3D models created from magnetotelluric data, a passive a geophysical technique that measures the earth's natural electric and magnetic fields, to image the earth from surface to a depth of 40 km. We identified a voluminous igneous intrusion that extends from the surface to great depths in the earth's crust. We propose that this intrusion may have contributed to the uranium endowment of the basin, and that radiogenic heat from the large igneous body helped circulate uranium‐bearing fluids through the shallow crust along reactivated geologic structures. The modeling, when combined with other geoscientific datasets, showcases the role of high‐heat producing granitic intrusions in driving the hydrothermal fluid cells that formed the deposits. Key Points: Integrated resistivity—gravity modeling over the Arrow uranium deposit in CanadaMagnetotelluric inversion images deep‐seated thermal source and fluid pathways that formed some of the highest‐grade uranium depositsHolistic ore system model illustrates relationship between crustal ore system and lower crustal resistivity anomalies [ABSTRACT FROM AUTHOR]

Introduction: Improving health services integration through primary health care (PHC) teams for patients with chronic conditions is essential to address their complex health needs and facilitate better health outcomes. The objective of this study was to explore if and how patients, family members, and caregivers were engaged or wanted to be engaged in developing, implementing and evaluating health policies related to PHC teams. This patient‐oriented research was carried out in three provinces across Canada: British Columbia, Alberta and Ontario. Methods: A total of 29 semi‐structured interviews with patients were conducted across the three provinces and data were analysed using thematic analysis. Results: Three key themes were identified: motivation for policy engagement, experiences with policy engagement and barriers to engagement in policy. The majority of participants in the study wanted to be engaged in policy processes and advocate for integrated care through PHC teams. Barriers to patient engagement in policy, such as lack of opportunities for engagement, power imbalances, tokenism, lack of accessibility of engagement opportunities and experiences of racism and discrimination were also identified. Conclusion: This study increases the understanding of patient, family member, and caregiver engagement in policy related to PHC team integration and the barriers that currently exist in this engagement process. This information can be used to guide decision‐makers on how to improve the delivery of integrated health services through PHC teams and enhance patient, family member, and caregiver engagement in PHC policy. Patient or Public Contribution: We would like to acknowledge the contributions of our patient partners, Brenda Jagroop and Judy Birdsell, who assisted with developing and pilot testing the interview guide. Judy Birdsell also assisted with the preparation of this manuscript. This study also engaged patients, family members, and caregivers to share their experiences with engagement in PHC policy. [ABSTRACT FROM AUTHOR]

The McMurray Formation in McMurray Depocentre, Canada, is typically subdivided into stratigraphic units based on regionally mappable marine mudstones, the bases of which define flooding surfaces (bottom to top: Lower McMurray, C2, C1, B2, B1, A2, A1 depositional unit). However, the McMurray Formation comprises a variety of palaeoenvironments, with the north‐eastern Firebag Tributary hosting significant delta‐plain deposits in the Lower McMurray and B1 depositional units. Facies analysis of 60 cores and 4763 wireline logs was used to resolve the palaeoshoreline trajectory and stratigraphic architecture in Firebag Tributary. Of 14 identified facies, three delta‐plain facies reveal: (1) eluviated palaeosols, interpreted as shrublands and woodlands formed during base‐level fall; (2) gleyed palaeosols, interpreted as tidal marshes; and (3) coals formed in coastal mires, the two latter facies are interpreted to accumulate during base‐level rise. Eluviated palaeosols occur below the Lower McMurray coal seam, implying valley incision and a maximum regressive surface. Gleyed palaeosols underlying the coal seam atop the B1 depositional unit do not record base‐level fall. Wetting‐upward coals overlying either palaeosol facies indicate base‐level rise (i.e. major flooding surface). B1 depositional unit coals and gleyed palaeosols are overlain by shallow‐marine facies or are eroded by wave ravinement during transgression. Consequently, the tops of coals or gleyed palaeosols correlate to the bases of regional marine mudstones elsewhere in McMurray Depocentre. Stratigraphic cross sections showcase palaeoshoreline regression and transgression. During the Lower McMurray and B1 depositional units, widespread coals and palaeosols indicate the palaeoshoreline resided near the western edge of Firebag Tributary. Regression during C2 through B2 depositional units and A2 and A1 depositional units resulted in palaeoshorelines near the Alberta–Saskatchewan border. To complement a previously dated Lower McMurray ash (121.39 ± 0.2 Ma), a new high‐confidence maximum depositional age from ash in the B1 coal seam (115.09 ± 0.16 Ma) allows an estimate to be made of depositional duration, indicating depositional units represent ca 0.16 Myr. [ABSTRACT FROM AUTHOR]

Several lacustrine carbonate beds, each a metre‐thick interval of densely packed Mn‐rich sideritic micro‐spherulites or Mn‐rich ferroan calcite micro‐spherulites, are recorded for the first time within strata of the Lower Cretaceous McMurray Formation of the northern Athabasca Oil Sands deposit, western Canada. A lower McMurray lacustrine carbonate deposit is characterised by a metre‐thick bed fabric of Mn‐rich siderite micro‐spherulites. The middle and upper interval McMurray beds developed fabrics of Mn2+‐rich ferroan calcite micro‐spherulites. These carbonate beds represent saline lacustrine depositional environments that resulted from the lake bottom sediments ingressed from below by Mn2+‐Fe2+‐rich carbonate‐saturated brines. These up‐section migrations of Devonian formation water were sourced from dissolution trends developed in limestone and halite‐anhydrite beds of the underlying Devonian Prairie Evaporite during Cordilleran deformation of the Alberta Basin foreland. These brines ascended to the overlying McMurray Formation sediments along dissolution‐collapse structures such as breccia pipes, sinkholes and margins of differentially subsided Upper Devonian fault blocks. The up‐section migration of a sulphate‐saturated Fe2+ and Mn2+‐rich brine resulted in the ingress of a lower McMurray lacustrine bottom sediment at a site associated with the development of a peat mire terrain. Microbial redox of the lake bottom sediment resulted in a carbonate bed of micro‐spherulitic fabrics of Mn‐rich siderite interwoven with pyrite laminae. Subsequent salt dissolution events and up‐section migrations of Devonian brine during deposition of the middle and upper McMurray intervals resulted in similar carbonate‐saturated but sulphate‐poor chemistry. These saline flows also ingressed lacustrine bottom sediments below, and resulted in limestone beds of densely packed spherulitic fabrics of Mn‐ferroan calcite, not siderite. These deposits provide insight into largely unknown dispositions of voluminous brine resulting from salt dissolution trends below the Athabasca Oil Sands and further our understanding of controversial McMurray depositional processes. [ABSTRACT FROM AUTHOR]

Meteorite impact‐induced mobilization of a volcanic ash tuff resulting in 100s of m long lithified clastic dikes is a novel mechanism in the geologic record. The Paleogene Eagle Butte impact event in southeastern Alberta, western Canada, resulted in a 10–17 km diameter central peak crater, now partially eroded and buried without expression at the surface. Impact shock waves, degraded to elastic waves, mobilized sediment 10s of km beyond the crater and resulted in a cluster of 100s of m long, 10–20 cm thick, dikes consisting of volcanic ash. It is not well understood how effective meteorite impact‐induced waves would be as triggers for sediment mobilization at areas 10s of km distant from an impact crater. Emplacement of the Manyberries dike cluster provides insight into this issue and confirms that shock waves, degraded to elastic waves, can indeed liquefy and mobilize sediments at distances as much as 5 crater radii beyond an impact site. These impact‐induced waves triggered liquefaction and mobilization of a shallowly buried Campanian‐Maastrichtian deposit of volcanic ash and injected the tuff sediment along impact‐induced faults. The lithification of the dike tuff, consisting of the cristobalite–tridymite groundmass, resulted from partial dissolution of glass shards and precipitation of opaline cement. These weathering resistant dikes of indurated tuff sediment extend for as much as 800 m on recessive Campanian‐Maastrichtian shale ridges of the badlands topography. [ABSTRACT FROM AUTHOR]

Paleopathology, or the study of ancient injuries and diseases, can enable the ecology and life history of extinct taxa to be deciphered. Large‐bodied ornithopods are the dinosaurs with the highest frequencies of paleopathology reported to‐date. Among these, the crested hadrosaurid Parasaurolophus walkeri is one of the most famous, largely due to its dramatic elongated and tubular nasal crest. The holotype of Parasaurolophus walkeri at the Royal Ontario Museum, Canada, displays several paleopathologies that have not been discussed in detail previously: a dental lesion in the left maxilla, perhaps related to periodontal disease; callus formation associated with fractures in three dorsal ribs; a discoidal overgrowth above dorsal neural spines six and seven; a cranially oriented spine in dorsal seven, that merges distally with spine six; a V‐shaped gap between dorsal spines seven and eight; and a ventral projection of the pubic process of the ilium which covers, and is fused with, the lateral side of the iliac process of the pubis. These lesions suggest that the animal suffered from one or more traumatic events, with the main one causing a suite of injuries to the anterior aspect of the thorax. The presence of several lesions in a single individual is a rare observation and, in comparison with a substantial database of hadrosaur paleopathological lesions, has the potential to reveal new information about the biology and behavior of these ornithopods. The precise etiology of the iliac abnormality is still unclear, although it is thought to have been an indirect consequence of the anterior trauma. The discoidal overgrowth above the two neural spines also seems to be secondary to the severe trauma inflicted on the ribs and dorsal spines, and probably represents post‐traumatic ossification of the base of the nuchal ligament. The existence of this structure has previously been considered in hadrosaurs and dinosaurs more generally through comparison of origin and insertion sites in modern diapsids (Rhea americana, Alligator mississippiensis, Iguana iguana), but its presence, structure, and origin‐attachment sites are still debated. The V‐shaped gap is hypothesized as representing the point between the stresses of the nuchal ligament, pulling the anterior neural spines forward, and the ossified tendons pulling the posterior neural spines backward. Different reconstructions of the morphology of the structure based on the pathological conditions affecting the neural spines of ROM 768 are proposed. Finally, we review the history of reconstructions for Parasaurolophus walkeri showing how erroneous misconceptions have been perpetuated over time or have led to the development of new hypotheses, including the wide neck model supported in the current research. [ABSTRACT FROM AUTHOR]

This paper examines patterns of structure in the helminth communities of long-billed curlews collected on their breeding grounds in Alberta, Canada. The communities are neither large nor species rich but they do show evidence of having structure which is mediated by interactive mechanisms between some helminths. In particular, we focus on the role played by congeneric host-specialists in contributing to community patterns and suggest that even in low diversity systems, some species may set the stage around which other species must assort. [ABSTRACT FROM AUTHOR]

Hyperspectral imaging can be used to rapidly identify and map the spatial distributions of many minerals. Here, hyperspectral mapping in three wavelength regions (visible and near‐infrared, shortwave infrared, and thermal infrared) was applied to drill cores (ST001, ST002, and ST003) penetrating a continuous sequence of crater‐fill breccias from the Steen River impact structure in Alberta, Canada. The combined data sets reveal distinct mineralogical layering, with breccias derived predominantly from sedimentary rocks overlying those derived from granitic basement. This stratigraphy demonstrates that the breccias were not appreciably disturbed following deposition, which is inconsistent with formation models of similar breccias (suevites) by explosive impact melt–fluid interaction. At Steen River, volatiles from sedimentary target rocks were an inherent part of forming these enigmatic breccias. Approximately three quarters of terrestrial impact structures contain sedimentary target rocks; therefore, the role of volatiles in producing so‐called suevitic breccias may be more widespread than previously realized. The hyperspectral maps, specifically within the SWIR wavelength region, also delineate minerals associated with postimpact hydrothermal activity, including ammoniated clay and feldspar minerals not detectable using traditional techniques. These nitrogen‐bearing minerals may have originated from microbial processes, associated with oil‐ and gas‐producing units in the crater vicinity. Such minerals may have important implications for the production of habitable environments by impact‐induced hydrothermal activity on Earth and Mars. [ABSTRACT FROM AUTHOR]

In this paper, we examine the reorganizing attempts of the Alberta government in healthcare from the viewpoint of uncertainty, loose coupling and the frequently unrecognized consequences of such change. We suggest that our understanding of change processes can be enhanced by conceptualizing the impact of task and environmental uncertainty through the nature of coupling between organizational elements. Based on our findings, we propose that the greater the degree of loose coupling in an organization, the more difficult change is likely to be, and the more likely the occurrence of unanticipated consequences. [ABSTRACT FROM AUTHOR]

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1. Oil sands mining is one of several industrial activities that produces effluent that is dangerous to waterfowl. Such industries require effective systems to deter birds, but current deterrents are not always successful, presumably because wildlife ignore or habituate to them. 2. We tested a new radar-activated on-demand system of deterrence in the oil sands region of Alberta, Canada, by comparing the proportion of birds that landed on a tailings pond while it was activated with the proportion that landed during two other treatments: a continuous, randomly activated, deterrent system, and control periods with no deterrents. We also assessed the efficacy of different stimuli types within the on-demand system. 3. Across several bird guilds, only the on-demand deterrent system significantly reduced the probability of birds landing in comparison with the control treatment. In addition to treatment effects, birds were more likely to land earlier in the spring and when they flew at lower altitudes, and shorebirds were more likely to land than ducks, geese and gulls. 4. The comparison of stimuli revealed that cannons elicited significantly more response by birds in flight than mechanized peregrine falcon effigies with speakers broadcasting peregrine sounds. 5. Synthesis and applications. Our results promote the use of on-demand systems for waterfowl deterrence at tailings ponds and recommend cannons over effigies as stimuli. We suggest that oil sands deterrence efforts should (i) be operational in the early spring, when tailings ponds appear to be most attractive to migrating waterfowl, (ii) target low-flying waterfowl and shorebirds and (iii) be effective during both day and night. These results and recommendations have potential application for problems of bird deterrence at several other industrial sites. [ABSTRACT FROM AUTHOR]

Ecoregions represent biophysical zones where environmental factors enable the development of particular plant communities. Ecoregions are generally large but abrupt transitions occur in areas with rapid physical change. A particularly abrupt transitional sequence occurs in the Rocky Mountain region of south-western Alberta where fescue prairie, aspen parkland and mountain ecoregions occur within 15 km. To investigate plant adaptation across ecoregions, our study investigated the influences of a natural disturbance (flooding) and an artificial disturbance (cattle grazing) on reproductive and population processes of black cottonwood ( Populus balsamifera subsp. trichocarpa, Torr. & Gray), the dominant riparian tree. We studied cottonwoods throughout their elevational range along two free-flowing, first-order streams, Yarrow and Drywood creeks. Cottonwood was the only prominent tree in the prairie ecoregion, the dominant riparian tree in the parkland and extended upward through the montane ecoregion where it was a pioneer species for the mixed coniferous–deciduous woodland. Cottonwoods did not occur in the higher elevation sub-alpine ecoregion. Thirty-six cross-sectional sampling transects were located across the three ecoregions with cottonwoods, and in ungrazed and grazed areas of each ecoregion. Rectangular 100 m2 tree and 2 m2 seedling quadrats were positioned along the transects, and substrate and vegetation were assessed. Historic hydrological data were analysed relative to flood recurrences and seasonal flow patterns. Overall, the cottonwoods displayed a sawtooth shaped ‘punctuated progressive age structure’ with many young trees, progressively fewer older trees, and about four pulses of increased recruitment over the past century. This was considered to provide a healthy cottonwood population and recruitment pulses were apparently associated with flood events with appropriate peak timing and magnitude and a gradual post-flood stage recession. However, analyses of tree, sapling and seedling data indicated that flood-associated seedling recruitment was less important and clonal processes were more important for cottonwood recruitment in the montane ecoregion, the highest ecoregion with cottonwoods. The correlation between flood events and cottonwood recruitment was strongest in the mid-elevation parkland ecoregion suggesting greater reliance on flood-associated seedling recruitment. There was little correlation with flooding and limited recruitment in the fescue prairie ecoregion in recent decades and the disturbed age structure probably results from cattle impacts that have prevented recruitment and produced a decrepit cottonwood forest population. These analyses suggested that a healthy cottonwood population displayed a sawtooth shaped ‘punctuated progressive age structure’ and that cottonwood reproduction processes varied across ecoregions with increased clonality in the highest montane ecoregion. Cattle grazing impacts on reproduction were most severe in the lowest prairie ecoregion that is treeless except for the riparian zone. We conclude that appropriate strategies of instream flow regulation, land-use policies and practices, and conservation and restoration efforts should be refined according to ecoregion to recognize the differences in cottonwood reproductive and population ecology. [ABSTRACT FROM AUTHOR]

Summary A field experiment in a native grassland in Central Alberta, Canada, tested whether plants alter relative allocation to roots vs. shoots in response to below-ground competition, and whether the mass of a species’ root system accounts for interspecific differences in below-ground competitive response. 2 Seedlings of each of 10 native species were transplanted into the naturally occurring vegetation in the field at the start of the growing season. Root interactions between the target plants and their neighbours were manipulated through the use of PVC root exclusion tubes, with target plants grown with or without potential root interactions with their neighbours. Neighbour shoots were also tied back, forcing any target–neighbour interactions to be below ground. 3 Below-ground competition generally reduced plant growth, with its relative magnitude varying among species. 4 An allometric analysis indicated that competition below ground did not result in an increase in the relative biomass allocated to roots for any of the 10 target species. This is counter to the growth-balance hypothesis (and optimal foraging theory). Below-ground competition did increase root : shoot ratios, but this was due to reduced plant size (small plants have larger root : shoot ratios), rather than adaptive plasticity. 5 A species’ below-ground competitive ability was not related to its root system size. Although this finding is counter to commonly made assumptions, it is supported by other work demonstrating below-ground competition to be generally size-symmetric. 6 Despite the majority of plant–plant interactions in grasslands being below ground, our understanding of plant competition above ground is significantly more robust. Several wide-spread assumptions regarding below-ground competition are suspect, and more multispecies studies such as this are required to provide a fuller picture of how plants respond to, and compete for, soil resources. [ABSTRACT FROM AUTHOR]

Examines the process of migration based on the Mennonite history and its role in the Old Colony in Northern Alberta. Fundamental objective of all Old Colony migrations; Traditional curriculum of Mennonite school; Expansion of non-Old Colony groups within the community.

The relative virulence of 109 Ascochyta isolates collected from pea fields in Alberta from 1996 to 1998 were evaluated on 10-day-old seedlings by the excised leaf-assay technique. Twenty-eight isolates were avirulent, while the others produced lesions of various sizes on pea leaves. DNA samples from 86 isolates were amplified by the RAPD technique using PCR with single primers. One dominant genotype of Ascochyta pisi was identified throughout Alberta, but variations in virulence were not clearly differentiated by the RAPD technique. Five Ascochyta isolates, four virulent and one avirulent, were used to assess the susceptibility of 20 field pea cultivars available in Alberta, including 13 yellow types and seven green types. Based on symptom development, the yellow-type cultivars Swing, Eiffel and Delta, and the green-type cultivar Orb, were the most susceptible. Of yellow-type cultivars, Voyageur, Carneval and Montana were most resistant to Ascochyta infection. [ABSTRACT FROM AUTHOR]

SummaryA recently established population of Pterostichus melanarius Ill., a wing-dimorphic, introduced carabid beetle species, was studied over a 7-year period in Alberta, Canada. We monitored local colonization, and tested classical hypotheses about spatial and temporal changes in proportion of flight-wing morphs in the Carabidae. Between 1991 and 1997, a sizable population in a road verge (0.17 individuals/trap/day in 1991) expanded only slowly into an adjacent aspen-poplar forest: the catch of 0.005 ind./trap/day in the forest in 1997 was not significantly higher than that of 0.001 ind./trap/day in 1991. However, a significantly higher proportion of P. melanarius were macropterous, long-winged (LW) in the forest (80%) than in the road verge and at the forest edge (54%). This supports the hypothesis that newly established populations are characterized by a high proportion of LW individuals, and further indicates that dispersal from the road verge into the forest has taken place primarily through flight. The overall proportion of flightless, brachypterous individuals (SW) captured at the study site increased from 39% in 1991 and 1992 to 57% in 1997, supporting the hypothesis that the proportion of SW individuals will increase with time since establishment of a population. Captures of P. melanarius in the forest were patchy and concentrated in particular areas throughout the study. However, these bridgehead’ populations did not grow or expand obviously, suggesting that populations adapt to forest conditions or reach some threshold size before effective expansion. [ABSTRACT FROM AUTHOR]

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The strategy of managing for 'natural' patterns towards ecological sustainability of forests is currently limited to simple spatial attributes of landscapes. Yet, there is general agreement that landscapes are highly dynamic entities suggesting that temporal patterns may also be important. This study used historical estimates of 20-year disturbance rates, and a spatially explicit, stochastic landscape model tocreate multiple possible landscape mosaic scenes for three differentlandscapes in the Foothills of Alberta. The results were summarized as frequency distributions by age- class, and the distributions compared to the percentage of area in the current, and the pre-commercial landscapes. Results indicated that aside from one age-class in one ofthe landscapes, both current and pre-commercial age-class distributions were well within the historical ranges suggested by the simulations. More generally, the simulations indicated relatively high, but landscape specific, levels of historical temporal variability. This implies that there are patterns to temporal variability which may be captured, quantified, and emulated as alternatives to single age-class management targets. The research also demonstrates a method of assessing age-class distributions within the context of historical ranges ofdistributions. [ABSTRACT FROM AUTHOR]

Examines the relationship between firm size and loss costs using automobile insurance industry data for Alberta for the years 1978 through 1981. Effectiveness of large firms in screening; Description of the Carlson and McAfee model of price dispersion; Prediction of screeners to include large firms and high-risk drivers; Driver class definitions and proportions of insured cars.

Studies the theory that perceptions of job facet satisfaction are weighed by importance with reference to elementary and junior high school principals in Alberta, Canada. Importance of job facets for satisfaction; Satisfaction with job facets and overall job satisfaction; Satisfaction ratings.

Examines the geographical aspects of constraints on leisure and recreation by using secondary analysis of data from a survey conducted in Alberta. Review of previous research; Methodology; Relative importance of geographical constraints; Comparison of regional and age-based variation in constraints; Discussion of results.

Assesses the locational decisions made by pioneering agriculturalists in the process of occupying an area in consideration of the physical environment within which they were made. Significance of vegetation; Surveys and vegetation classification; Limitations in using surveyors' notebooks.

Glock, Ringer, and Babbie have argued that people who become involved in church are seeking a comfortable refuge from the deprivations associated with being old, female, unmarried, or having a small income or little education. The present research tests this thesis using data from a province wide sample of adults in Alberta. No support for the thesis is found among any denominational grouping. When the thesis is broken down into its component hypotheses, however, the pattern of relationships that emerges is one that has long been familiar to sociologists. [ABSTRACT FROM AUTHOR]

Costs and supply in petroleum exploration: the case of Alberta. A stochastic production function for the discovery of new petroleum reserves is developed which incorporates the following features: the effects of the accumulation of geological knowledge, the effects of the eventual exhaustion of undiscovered reserves, and the tendency for the largest reservoirs to be found early in the development of a region. The associated marginal exploration cost function, which is the quantity of ultimate interest, is derived from the production function in the usual way. The marginal exploration cost function is then estimated for several traditional producing regions in Alberta by estimating the parameters of the production function directly. The empirical results indicate that marginal exploration costs are rising rapidly in these regions. [ABSTRACT FROM AUTHOR]

The ground beetle Pterostichus, melonarius (Coleoptera, Carabidae), of European origin, is abundant and wide-spread in the northern United States and southern Canada. Three field enclosures were used in a four-year experiment in Alberta, Canada, to examine whether the species is able to establish in natural aspen-poplar forest, and to test the hypothesis that it has an adverse effect on the native carabid assemblage. After introduction to the enclosures P. melanarius maintained breeding populations in them, establishing that the forest is suitable habitat for the species, and suggesting that the species will eventually invade from nearby populations Pterostichus melanarius had no negative effect on population size or body mass of the native carabid species. However, the two most abundant native species (Ptero-stichus adstrictus and P. pensylvanicus) appeared to be more active (measured as escape rate) in compartments where they co-occurred with P. melanarius. Although the three enclosures were just a few metres apart, one of them consistently yielded the highest densities of all carabid species. This difference was correlated with high abundance of earthworms and low liner accumulation. Relatively low densities of P. melanarius may explain the lack of negative interspecific interactions in forests, although such effects are suggested by data from urban and agricultural environments where P. melanarius is more abundant. [ABSTRACT FROM AUTHOR]

Flooding patterns and variations in the composition and successional trends of riparian vegetation in the upper and lower Red Deer River in southern Alberta, Canada, were studied in order to establish which flood regimes were most important in the regeneration and maintenance of riparian vegetation communities, with a particular focus on riparian poplars. The dominant riparian tree in the upper river is Populus balsamifera with some Picea glauca and in the lower river Populus deltoides (the plains cottonwood). Dendrochronological studies of the poplars along the river show that major periods of regeneration correspond with major flood events during the record period. Extensive cottonwood regeneration occurred in the period 1900-20, corresponding with a series of floods, some as high as the 1 in 100-year event. In addition, just prior to and during this period there was a significant reduction in use of the floodplain by bison, clearance of forests and a higher incidence of fires in upper reaches of the river and a series of high rainfall years. A series of floods greater than the 1 in 10-year flood occurred in the 1950s and stimulated the most extensive regeneration of poplars experienced since the 1920s. Parts of the lower Red Deer floodplain are now at elevations well above the 1 in 100-year flood event. It is suggested that fringe replenishment of riparian poplars is currently the dominant form of regeneration and that the large stands of mature poplars found on the floodplain, initiated during the end of the last century and first decades of this century, are unlikely to be replaced unless large floods (>1 in 50-year events) occur again. Construction of the Dickson Dam above the city of Red Deer in 1983 has led to attenuation of floods and a reduced likelihood that extensive flooding and poplar regeneration will occur again. A number of recommendations are made regarding flow management to both retain the fringe regeneration of poplars currently occurring and to stimulate more widespread regeneration of poplars on the floodplain. [ABSTRACT FROM AUTHOR]

Evaluates economic factors that influenced the development and continuing concentration of the Canadian prairie feedlot industry in Southern Alberta. Determinants of the location of the prairie feedlot industry; Comparison with wheat production; Structural aspect of the prairie feedlot industry.

Presents a study about the effect of supply management on herd size in Alberta dairy. Theoretical model of supply management and complementary input dynamics; Empirical evidence of quota quasi-fixity; Several implications following the results of the study.

We used repeat oblique photography to quantify and determine the drivers of vegetation change, particularly forest closure and encroachment, in the Rocky Mountains of southern Alberta, Canada, from the beginning of the twentieth century to the present. We classified the landscape into seven distinct vegetation types (closed‐canopy conifer forest, broadleaf deciduous forest, mixedwood forest, open‐canopy woodlands, shrublands, grasslands and meadows, non‐vegetated) and assessed vegetation change between the two time periods. We found that closed‐canopy coniferous forest, broadleaf deciduous forest, and mixedwood forest increased on an area basis by 35%, 45%, and 80%, respectively, over this time period; concomitantly, grasslands and open‐canopy woodlands declined by 25% and 39%, respectively. Overall, 28% of the landscape was in a more advanced successional state in 2008 as compared to the early twentieth century. The Montane and Subalpine Natural Subregions (NSR) experienced the most change (42% and 26%, respectively, in a more advanced successional state). The loss of open‐canopy woodlands was observed across the entire landscape, while grassland and meadow losses were most acute in the Subalpine and Alpine NSRs. The probability of vegetation change to a more advanced successional condition was greater at higher elevations and in areas receiving lower amounts of solar insolation. The changes observed are consistent with what we would expect to see due to lengthening of fire return intervals. Understanding the magnitude of change in vegetation types and the drivers of this change is important for the development of effective contemporary ecosystem management and restoration practices. [ABSTRACT FROM AUTHOR]

Boreal woodland caribou (Rangifer tarandus caribou) are currently listed as threatened in Canada, with populations in the province of Alberta expected to decline as much as 50 percent over the next 8–15 yr. We assessed the future of caribou habitat across a region of northeast Alberta using a model of habitat‐quality and projections of future climate from three general circulation models. We used mapped climatic and topo‐edaphic properties to project future upland vegetation cover and a fire simulation model to project the frequency and extent of wildfires. Based on those projections, we quantified the future habitat of caribou according to estimates of nutritional resources and predation risk derived from vegetation cover type and stand age. Grassland vegetation covered up to half of the study area by the 2080s, expanding from <1% in the present and contributing to a significant contraction in mixedwood and coniferous forests. This change in vegetation would increase the risk of predation and disease, as habitat becomes more suitable for white‐tailed deer (Odocoileus virginianus) and, consequently, gray wolves (Canis lupus). Borne out, these changes would severely compromise the long‐term persistence of caribou in the boreal forest of Alberta. [ABSTRACT FROM AUTHOR]