Lethbridge College

Lethbridge, Canada

Lethbridge College

Lethbridge, Canada
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Saline-sodic shale overburden associated with oil sand mining is a potential source of salt release to surface water and groundwater and can lead to salinization and/or sodification of reclamation covers. Weathering of shale overburden due to oxidation of sulphide minerals within the shale leads to sulphate (SO4 2−) production and increased salinity. The controls on the rates of weathering of a shale overburden dump in the oil sands region of northern Alberta were determined from soil chemistry sampling and in situ monitoring of pore gases (O2, CO2, CH4) in three shallow profiles (1.9–4.45 m deep) and one deep (25 m deep) profile under reclamation covers of varying thickness. Oxidation, defined by the depth over which O2 concentrations were depleted, reached depths of approximately 1.1 m under the reclamation soil covers over a 6 year period after dump placement. Calculations of SO4 2− production rates and weathering depths were consistent with numerical simulations of the diffusion and subsequent consumption of atmospheric O2 in the overburden. The rate of SO4 2− production during the 6 year weathering period estimated from direct measurements of solids chemistry ranged from 0.70 to 8.3 g m−2 day−1. The rates calculated from the oxygen diffusion models were within that same range, between 1.6 and 4.1 g m−2 day−1. © 2017 Springer-Verlag Berlin Heidelberg


Diochon A.,Lakehead University | Basiliko N.,Laurentian University | Krzic M.,University of British Columbia | Yates T.T.,University of Saskatchewan | And 4 more authors.
Canadian Journal of Soil Science | Year: 2017

Global declines in postsecondary enrollment in soil science programs over the last several decades have been mainly attributed to an overemphasis on the connection with agronomy and production agriculture but recent enrollment increases in the USA suggest change is afoot. To determine if similar trends are occurring in Canada, we inventoried undergraduate soil science course offerings at postsecondary institutions and conducted a survey to assess the status and projected trends in soil science education. We found that 64% of universities and 37% of colleges offer undergraduate soil science courses as part of degrees or diplomas in which knowledge of soil science is important (e.g., agriculture and resource management). In Canada, there are 149 undergraduate soil science courses taught in universities and 58 at colleges. On average, there are 3.2 courses taught at each university and 1.9 at each college that offer soil science courses. Soil science programs at the University of British Columbia, University of Saskatchewan, and University of Manitoba offer between eight and nine soil science courses and represent 17.4% of the national total. Enrollments in all courses across the country are projected to be steady with some anticipated growth, trends that are consistent with those reported in the USA and the Netherlands. © 2017, Agricultural Institute of Canada. All rights reserved.


PubMed | University of Lethbridge and Lethbridge College
Type: | Journal: Dementia (London, England) | Year: 2016

Moral distress is increasingly being recognized as a concern for health care professionals. The purpose of this study was to explore the nature and prevalence of moral distress among nursing staff who care for people living with dementia.This study was focused on nursing staff caring for people with dementia in long-term care and assisted living sites. The Moral Distress in Dementia Care Survey instrument was distributed to 23 sites and nursing staff rated the frequency and severity of situations that were identified as potentially causing moral distress.Moral distress is prevalent in the nursing staff who provide dementia care. Nursing staff reported experiencing moral distress at least daily or weekly. Both frequency and severity of moral distress increased with proximity to (amount of time spent at) the bedside. Moral distress had negative psychological and physiological effects on nursing staff, and affected intention to quit.


Franke A.,University of Alberta | Galipeau P.,University of Quebec at Rimouski | Nikolaiczuk L.,Lethbridge College
Arctic | Year: 2013

This note describes an observation of infanticide in the Peregrine Falcon (Falco peregrinus tundrius). During the summer of 2011, a marked adult female and an unmarked adult male produced and hatched two eggs at a known and regularly monitored nest site. Motion-sensitive camera images indicated that the adults attended to the two nestlings and fed them in a manner that resulted in growth and development typical for the nestlings produced in the study population. During a period of intense rainfall, the two nestlings were left unattended for several hours; both nestlings were clearly distressed, and one was close to death. When the visibly wet marked adult female returned to the nest ledge, she killed and partially consumed the smaller and weaker of the two nestlings. The female flew from the nest ledge without feeding the remaining nestling and returned shortly afterward to kill and partially consume the second nestling. This is the first documentation of infanticide in wild Peregrine Falcons.


Beres B.L.,Agriculture and Agri Food Canada | Carcamo H.A.,Agriculture and Agri Food Canada | Byers J.R.,Agriculture and Agri Food Canada | Clarke F.R.,Agriculture and Agri Food Canada | And 4 more authors.
Canadian Journal of Plant Science | Year: 2013

The wheat stem sawfly (WSS) Cephus cinctus Norton (Hymenoptera: Cephidae) is an economically destructive insect pest of wheat in the northern Great Plains. Solid stem cultivar selection is one critical component to the integrated management of WSS. A significant resurgence of WSS in the southern prairies of Canada caused substantial economic losses from 1999 through 2007, which was compounded by the low adoption rate of solid-stem cultivars. A study was conducted from 2003 to 2005 in southern Alberta and Saskatchewan, Canada: (1) to characterize resistance levels in solid-stem germplasm derived from S615 and alternate genetic backgrounds, and (2) to determine the impact of host plant tolerance on WSS population dynamics. The tetraploid cultivar Golden Ball and its hexaploid derivative G9608B1-L-12J11BF02 were the most consistent at reducing damage, larval growth (fitness), and fecundity of WSS. The challenge will be to maintain this level of efficacy as the Canada Western Red Spring phenotype is reintroduced into the germplasm. Our study suggests solid-stem cultivars are highly effective but prone to inconsistent performance and should therefore be integrated into a holistic strategy for WSS that includes agronomics and biocontrol.


Beres B.L.,Agriculture and Agri Food Canada | Carcamo H.A.,Agriculture and Agri Food Canada | Byers J.R.,Agriculture and Agri Food Canada | Clarke F.R.,Agriculture and Agri Food Canada | And 3 more authors.
Canadian Journal of Plant Science | Year: 2013

The wheat stem sawfly (WSS) Cephus cinctus Norton (Hymenoptera: Cephidae) is an economically destructive insect pest of wheat in the northern Great Plains. A significant resurgence of the insect pest in the southern prairies of Canada caused substantial economic losses from 1999 through 2007. Solid-stem cultivar selection is critical to the management of WSS but adoption of the use of these cultivars was low, which compounded losses at harvest. A study was conducted from 2001 to 2003 in southern Alberta and Saskatchewan, Canada (1) to establish the range of susceptibility of hollow- and solid-stem varieties representing the major spring wheat classes and (2) to determine the impact of host plant on WSS population dynamics. The solid-stem varieties were generally superior at reducing damage and fitness response of WSS. However, in addition to the durum cultivars AC Navigator and AC Avonlea, the variety McKenzie, which was considered hollow, provided improved efficacy over other hollow-stem cultivars. Our study suggests solid-stem cultivars are highly effective but prone to inconsistent performance and should therefore be integrated into a holistic strategy for WSS that includes agronomics and biocontrol. A companion paper will report on the response of cultivars with novel sources of germplasm.


Peterson C.D.,Portland State University | Roberts M.C.,Simon Fraser University | Vanderburgh S.,Lethbridge College | Minor R.,Heritage Research Associates Inc. | Percy D.,Portland State University
Geomorphology | Year: 2014

The upper reaches of the lower Columbia River Valley (125km in length) comprise an alluvial system that is transitional between fluvial and fluvial-tidal dominance. Sinuous channels separate elongate islands (1-8km in length) and floodplains (0.5-12.7km in total width). Thirty-six floodplain overbank deposits are analyzed for age and depth, which demonstrate an average sedimentation rate of 1.6mka-1 during the last 5-6ka. Older core records confirm that long-term depositional rates are controlled by relative sea level rise. Rising floodplain groundwater surfaces, which followed relative sea level rise (~1.25mka-1), submerged isolated floodplain depressions. Low sedimentation rates in the isolated depressions (0.6-1.1mka-1) maintained large ellipsoidal bullseye lakes (7-22km2 in area) dating back to 3.5-4.0ka. Increases in the widths of the floodplains and bullseye lakes are associated with broadening of the incised valley (4-13km width) in the Portland Basin. Dated basal overbank deposits (0.5-5.0ka in age) and their separation distances establish channel migration rates of 0.3-1.9kmka-1. Shallow burial rates relative to rapid channel migration rates resulted in reworking of late Holocene floodplains (50-75% erosion) since 5ka in the upper reaches of the lower Columbia River Valley. © 2013 Elsevier B.V.


Peterson C.,Portland State University | Minor R.,Heritage Research Associates Inc. | Gates E.B.,128 NW Harriman Street | Vanderburgh S.,Lethbridge College | Carlisle K.,Hoover
Journal of Coastal Research | Year: 2012

Peterson, C.; Minor, R.; Gates, E.B.; Vanderburgh, S., and Carlisle, K., 2012. Correlation of tephra marker beds in latest Pleistocene and Holocene fill of the submerged Lower Columbia River Valley, Washington and Oregon, U.S.A. Seven tephra layers in the submerged fill of the Lower Columbia River Valley (LCRV) are radiocarbon dated (0.5-13 ka in age). They are correlated to reported eruption sources in the adjacent Cascade Range volcanic arc. The tephras provide a stratigraphic framework for the transgressive depositional filling of the tidal Columbia River system (∼200 km in length). The thickest and most continuous tephra marker beds in the LCRV are from the Mount Mazama set-O eruption at 7.7 ka. The eruption source for this tephra (1-10 m thick) is confirmed by glass geochemistry and radiocarbon dating of borehole samples from depths of -13 to -38 m (North American Vertical Datum of 1988 [NAVD88]). The Mazama set-O tephra conveniently divides the depositional sequences of the Early Holocene from the Late Holocene in the deep valley fill (50-120 m axial valley depth). A much deeper tephra, at -84 m, is attributed to Mount St. Helens set-S/J eruptions at ∼13 ka, which confirms the end of the Glacial Lake Missoula Flooding in the LCRV. Late Holocene tephra marker beds in the LCRV include the Mount St. Helens set-J/P eruptions (2.5-4.0 ka), set-W/T eruptions (∼AD 1480), and an intermediate-depth tephra, attributed to a Mount St. Helens or Mount Adams eruption (∼1.3 ka). The Late Holocene tephras date the ages of tidal flats and extensive floodplains throughout the length of the LCRV. The Late Holocene marker beds provide the first widespread constraints on wetland sedimentation rates and preservation potentials for archaeology sites in the LCRV. © Coastal Education & Research Foundation 2012.


Arsenault R.,University of Witwatersrand | Arsenault R.,Lethbridge College | Owen-Smith N.,University of Witwatersrand
Canadian Journal of Zoology | Year: 2011

Coexistence among grazing ungulates has been related to differences in grass height and grassland types selected, underlain by morphological distinctions. Nevertheless, resource competition may arise when smaller species depress grass height below that suitable for larger species, whereas competition may be counteracted by facilitation when larger species increase the extent of high-quality grassland available. We investigated resource-use overlap between white rhinoceros (Ceratotherium simum (Burchell, 1817)), blue wildebeest (Connochaetes taurinus (Burchell, 1823)), and Burchell's zebra (Equus burchelli (Gray, 1824)) in the Hluhluwe-iMfolozi Park in South Africa. We recorded the grassland type favoured, grass species utilized, grass height grazed, and greenness selected during the dry seasons of 2 years. Blue wildebeest shifted their grazing away from lawn grassland in the drier year, whereas Burchell's zebra favoured lawn grassland only in the relatively wet year. White rhinoceros concentrated their feeding on lawn grassland throughout the dry seasons of both years, and favoured shorter grass than the other two grazers. Species characterizing grazing lawns contributed relatively more to the grass used by white rhinoceros in the drier year. Resource competition was potentially ameliorated by widened availability of lawn grassland promoted by white rhinoceros grazing. This counterbalancing of feeding competition and habitat facilitation enables the coexistence of these grazers despite similar food requirements.


PubMed | Lethbridge College and Agriculture and Agri Food Canada
Type: Journal Article | Journal: Genome announcements | Year: 2015

Pectobacterium atrosepticum is a common phytopathogen causing significant economic losses worldwide. To develop a biocontrol strategy for this blackleg pathogen of solanaceous plants, P.atrosepticum bacteriophage Peat1 was isolated and its genome completely sequenced. Interestingly, morphological and sequence analyses of the 45,633-bp genome revealed that phage Peat1 is a member of the family Podoviridae and most closely resembles the Klebsiella pneumoniae bacteriophage KP34. This is the first published complete genome sequence of a phytopathogenic P.atrosepticum bacteriophage, and details provide important information for the development of biocontrol by advancing our understanding of phage-phytopathogen interactions.

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