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Title: Ecological importance of licks to four ungulate species in north-central British Columbia.
Contributors: Jeremy B. Ayotte (author), Katherine Parker (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: No abstract available.
Discipline: Natural Resources & Environmental Studies
Date added: 2017-03-30T17:00:32.115Z

Title: Seasonal variability of fine-grained sediment morphology in a salmon-bearing stream.
Contributors: Jennifer L. McConnachie (author), Ellen L. Petticrew (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: No abstract available.
Discipline: Natural Resources & Environmental Studies
Date added: 2017-03-30T16:58:37.357Z

Title: Simulating past and future mass balance of Place Glacier using a physically-based, distributed glacier mass balance model
Contributors: Raju Aryal (author), Peter Jackson (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: The objective of this study is to develop a physically-based distributed glacier mass balance (GMB) model for Place Glacier, British Columbia, Canada, and apply the model to develop the historic and the future mass balance. The model is forced with climate data from Regional Atmospheric Modeling System (RAMS) mesoscale atmospheric model output from 1979-2008 for developing historic mass balance on Place Glacier. The model is also run in the future (2009-2040) to develop a projection of mass balance. The model simulated the historic glacier-wide summer and winter balance on Place Glacier satisfactorily. For all years, root mean squared error (RMSE) in simulated summer and winter balance are 0.43 m water equivalent (w.e.) and 0.27 m w.e., respectively. Over the period of 29 years, the model simulated a cumulative net mass balance of -33.72 m w.e. The model outperformed both empirical temperature index (TI) and enhanced TI models in simulating summer balance on Place Glacier when forced with the same RAMS variables. A linear regression model based on Singular Value Decomposition (SVD) technique is used for downscaling future climate projections from a suite of Global Climate Models (GCMs). The cross-validation of downscaled daily air temperature showed a strong correlation with the validation dataset (r~ =0.85, p <0.05). However, the RMSE in downscaled daily air temperature is large (=2.4~C). With spatially average correlation of 0.38 and RMSE of 7.5 mm day\u207b~ , the model for daily precipitation performed less satisfactorily in downscaling large-scale precipitation. For all variables, the error statistics improved with the monthly model. Future GCM projections form CanESM2, MIROC-ESM, MPI-ESM-LR, and HadGEM2-ES, are considered for downscaling. CanESM2 predicted a large negative glacier-wide net mass balance of -2.50 m w.e. for Place Glacier in the future. For the remaining GCMs, the average of net mass balance is \u20130.96 m w.e. The average of the cumulative mass loss predicted from GCMs other than CanESM2 is -31 m w.e. From 2009-2040, CanESM2, MIROC, MPI and HadGEM2 predicted an area loss of 52%, 28% and 22%, respectively. Overall, all downscaled GCMs, except CanESM2, performed better in predicting future mass balance for Place Glacier.
Discipline: Natural Resources & Environmental Studies
Date added: 2017-03-29T17:27:40.338Z

Title: Characterization of spawning habitat, incubation environment and early growth and development in bull trout (Salvelinus confluentus ) from pristine streams of northern British Columbia.
Contributors: Cory John Williamson (author), Mark Shrimpton (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: No abstract available.
Discipline: Natural Resources & Environmental Studies
Date added: 2017-03-30T17:02:56.781Z

Title: Effect of habitat quality on communication and signalling in the black-capped chickadee.
Contributors: Thibault Grava (author), Ken Otter (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: Vocal performance in songbirds describes the ability to repetitively perform energetically-expensive acts (vocal vigour) and/or to consistently perform difficult motor tasks (vocal skill). This concept is intrinsically correlated with the birds' condition - birds in better condition tend to signal with higher performance than birds in poorer condition (e.g. vocal performance is condition-dependent). Condition of birds, however, is also influenced by the habitat quality in which they settle, and has been well studied in the black-capped chickadee. My Ph.D thesis explores the links between habitat quality and vocal performance in this species. Previous studies have shown that habitat quality affects song output in this species (reduced vocal vigour in poor-quality habitat) and it was speculated that reduced song output may be linked to poorer condition of birds in these forests. To document the relationship between immediate food availability and vocal performance, I conducted a supplemental feeding experiment on male chickadees during the peak in dawn singing in early spring. My results demonstrate that food availability is an important factor influencing song output, and that song output reflects the condition of the birds at the time of singing. The difference in song output across habitats, thus, appears to relate to difference in food availability at the time of singing. The ability to maintain internal song structure (vocal skill) has previously been shown to be condition-dependent in chickadees, with dominant birds having better vocal skill than subordinate birds. My supplemental feeding study demonstrated that this vocal skill is not influenced by short-term resource availability to the signaller at the time of singing, but vocal skill is affected by habitat quality - birds in young forest habitats (poor-quality) are less able to maintain internal frequency ratios in their songs than birds in neighbouring mature forests (high-quality). The ability to maintain internal song ratios may rather reflect longer
Discipline: Natural Resources & Environmental Studies
Date added: 2017-03-30T17:14:28.064Z

Title: Resource development patterns of the British Columbia salmon canning industry, 1870 to 1970.
Contributors: Brian Dale Stauffer (author), Greg Halseth (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: No abstract available.
Discipline: Natural Resources & Environmental Studies
Date added: 2017-03-29T17:33:30.196Z

Title: Treatment of chromium contaminated soil by co-pyrolysis with rice straw
Contributors: Yimeng Chen (author), Ron Thring (thesis advisor), Hualin Chen (thesis advisor), University of Northern British Columbia College of Science and Management (Degree granting institution), Jianbing Li (committee member)
Abstract: The direct discharge of tannery waste and effluent could result in severe chromium (Cr) contamination in soils. This study focused on the remediation of Cr-contaminated soil via co-pyrolysis with rice straw. The influence of co-pyrolysis temperature, rice straw / soil mixing ratio and reaction time on Cr immobilization were investigated. Compared to untreated soil, the leachable Cr and total Cr(VI) in co-pyrolyzed soil were decreased by up to 95 % and 86 %, respectively. With increasing temperature and rice straw addition, the leachable Cr and total Cr(VI) were reduced. Reaction time did not show a significant effect on Cr immobilization. The time-varying desorption test indicated that the equilibrium amount of released Cr in various extractants was inhibited by co-pyrolysis. The Simple Bioaccessibility Extraction Test also showed that the bioaccessible Cr in the gastric phase was decreased after co-pyrolysis. The results suggested that co-pyrolysis was beneficial on Cr immobilization.
Discipline: Natural Resources & Environmental Studies
Date added: 2019-05-10T23:31:40.518Z

Title: Influence of temperature and precipitation on radial growth properties of hybrid white spruce (Picea glauca (Moench) x engelmannii (Parry)) in Central Interior British Columbia, Canada
Contributors: Anastasia Ivanusic (author), Lisa Wood (thesis advisor), Kathy Lewis (thesis advisor), Paul Bicho (committee member), University of Northern British Columbia (Degree granting institution)
Abstract: It is prudent to understand how changes in climate will affect tree-ring growth, wood fibre quality, and percent carbon content in natural and planted stands in central interior British Columbia (BC), as BC produces high volumes of wood fibres that are competitive in a global market. Wood properties within natural and planted stands of hybrid white spruce (Picea glauca (Moench) x engelmannii (Parry)) (percent carbon, ring-width, earlywood and latewood width and wood cell properties of cell wall thickness, density, microfibril angle, radial diameter and coarseness) were assessed to determine if climate variation is a limiting growth factor. Results show precipitation is an important limiting factor in planted stand growth with some indication that increasing temperatures limit growth in natural stands. Relationships between climate and percent carbon indicate that rising winter, spring, and summer temperatures coupled with reduced precipitation strongly limit percent carbon accumulation in most natural and planted stands.
Discipline: Natural Resource & Environmental Studies
Date added: 2020-05-28T21:29:52.118Z

Title: Integrating Aboriginal values into strategic-level forest planning on the John Prince Research Forest, Central Interior, British Columbia.
Contributors: Melanie Kirsti Karjala (author), Stephen Dewhurst (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: No abstract available.
Discipline: Natural Resources & Environmental Studies
Date added: 2017-03-30T16:58:23.029Z

Title: Monitoring habitat quality and condition of Queen Charlotte saw-whet owls (Aegolius acadicus brooksi) using vocal individuality.
Contributors: Carmen I. Holschuh (author), Kenneth Otter (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: No abstract available.
Discipline: Natural Resources & Environmental Studies
Date added: 2017-03-30T17:00:14.401Z

Title: Exposure to fine particulate air pollution in Prince George, British Columbia.
Contributors: Melanie Noullett (author), Peter Jackson (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: No abstract available.
Discipline: Natural Resources & Environmental Studies
Date added: 2017-03-30T17:00:33.627Z

Title: Development of modified natural zeolites and study of phosphate removal from aqueous solutions
Contributors: Saki Kondo (author), Ron Thring (thesis advisor), Hossein Kazemian (thesis advisor), University of Northern British Columbia College of Science and Management (Degree granting institution), Chris Opio (committee member)
Abstract: Lake eutrophication has been an issue in many countries including Canada. Controlling and reducing the level of phosphorus, which is available as a form of phosphate in water, have been studied to manage the lake eutrophication. Natural zeolite-based adsorbents are one of the best candidates for water treatment due to its wide availability, cost-effectiveness, and superior characteristics as an ion exchanger. In this study, the concept of struvite crystallization was employed to develop magnesium-ammonium-modified zeolites (MNZ). Their removal capacity of phosphate was tested with comparison of magnesium-modified zeolites (MZ) based on the design of experiments (DOE) and response surface methodology (RSM). According to RSM, MNZ was found to be more effective in removing phosphates from aqueous solutions up to 92% of removal since MZ was effective up to 46% of removal. Contact time and zeolite dosage were found to be the significant parameters on phosphate removal.
Discipline: Natural Resources & Environmental Studies
Date added: 2019-05-10T23:31:42.372Z

Title: Functional expression of Ips paraconfusus cytochromes P450 exhibiting conspicuous up-regulation with feeding on host phloem.
Contributors: Caitlin Pitt (author), Dezene Huber (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: Owing to the possible roles of insect P450s in detoxification of host material, and the biosynthesis or degradation of aggregation pheromones and hormones, these enzymes are ecologically important. Several Ips paraconfusus cytochromes P450 (P450s) were up-regulated with feeding on host phloem. Beetle P450s have previously been functionally characterized via heterologous expression in baculovirus/insect cell systems. Ips paraconfusus P450s were similarly expressed as proteins, and co-expressed with a P450 reductase. Capillary electrophoresis quantified recombinant enzymes during optimization efforts, augmenting spectral measurements. Various host secondary metabolites were tested as substrates, but functions were not determined, which may mean that the enzymes are not specific to those compounds. Although these P450s were microsomal, cellular fraction evaluation revealed possible mitochondrial and cytosolic targeting and two distinct size groups. These may represent the first insect examples of chimeric P450 signaling. The utility of capillary electrophoresis to streamline expression optimization and alternative targeting are discussed. --P. ii.
Discipline: Natural Resources & Environmental Studies
Date added: 2017-03-30T17:07:04.246Z

Title: Community adaptation to climate change: An exploration of climate change adaptation planning in British Columbia.
Contributors: Ian Picketts (author), John Curry (Thesis advisor), Eric Rapaport (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: Planners in British Columbia must adapt to climate change by preparing for expected and unexpected changes in their communities. The results of survey and workshop research conducted at the Planning Institute of BC conference indicate that planners do not have a high level of knowledge of climate change adaptation. Planners feel that the impacts that will affect BC the most in 50 years will be related to forests, agriculture, river flooding, transportation and water. Different regions in the province will be affected in different ways, and adaptation strategies must be created for the specific needs and attributes of a community. Open-structured workshops are a good method to educate planners about climate change adaptation however, they should not be expected to yield results that can be incorporated into planning documents. Global climate models are a valuable tool that decision makers can use to help determine appropriate planning actions. --P. ii.
Discipline: Natural Resources & Environmental Studies
Date added: 2017-03-30T17:07:50.439Z

Title: Growth of interior spruce and attack by the white pine weevil, Pissodes strobi (Peck) in the sub-boreal spruce zone of British Columbia: Role of overstorey shade.
Contributors: Susan M. Nykoluk (author), Chris Hawkins (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: No abstract available.
Discipline: Natural Resources & Environmental Studies
Date added: 2017-03-30T16:57:29.793Z

Title: Export barriers to the Chinese market: Insights from British Columbia forest products firms.
Contributors: Zhengzhe He (author), Christopher Opio (Thesis advisor), Jing Chen (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: Canada's forest products firms have endeavored to develop the Chinese market as their alternative export destination. These needs became even urgent since the US economic recession in 2008. Reducing the export barriers that firms encountered will minimize their losses and enhance their export performance in the Chinese market. Through a questionnaire survey, thirty-four managers in British Columbia's forest products firms identified and evaluated the barriers that hindering their exporting to the Chinese market. The identified nine export obstacles include difficulties in finding business opportunities, skillful personnel and foreign representatives differences in verbal, nonverbal language and socio-cultural traits, price competition and excessive transportation cost. The findings in this study also indicate that different parameters of firm size have different relationships with export barriers. In addition, different parameters of firm's export experience also show different relationships with export barriers. These findings will facilitate forest policy makers in British Columbia to formulate Chinese market export strategies, especially to target firms with different firm's size and export experience. --P.ii.
Discipline: Natural Resources & Environmental Studies
Date added: 2017-03-30T17:06:31.956Z

Title: The influence of warming, site characteristics, and host plant on root-associated fungal communities from Alexandra Fiord in the Canadian High Arctic.
Contributors: Kei E. Fujimura (author), Keith Egger (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: No abstract available.
Discipline: Natural Resources & Environmental Studies
Date added: 2017-03-30T17:14:02.071Z

Title: A multi-scale behavioural approach to understanding the movements of woodland caribou.
Contributors: Chris Jack Johnson (author), Katherine Parker (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: No abstract available.
Discipline: Natural Resources & Environmental Studies
Date added: 2017-03-30T17:13:57.317Z

Title: Sequential Monte Carlo methods for data assimilation in strongly nonlinear dynamics.
Contributors: Zhiyu Wang (author), Youmin Tang (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: Data assimilation is the process of estimating the state of dynamic systems (linear or nonlinear, Gaussian or non-Gaussian) as accurately as possible from noisy observational data. Although the Three Dimensional Variational (3D-VAR) methods, Four Dimensional Variational (4D-VAR) methods and Ensemble Kalman filter (EnKF) methods are widely used and effective for linear and Gaussian dynamics, new methods of data assimilation are required for the general situation, that is, nonlinear non-Gaussian dynamics. General Bayesian recursive estimation theory is reviewed in this thesis. The Bayesian estimation approach provides a rather general and powerful framework for handling nonlinear, non-Gaussian, as well as linear, Gaussian estimation problems. Despite a general solution to the nonlinear estimation problem, there is no closed-form solution in the general case. Therefore, approximate techniques have to be employed. In this thesis, the sequential Monte Carlo (SMC) methods, commonly referred to as the particle filter, is presented to tackle non-linear, non-Gaussian estimation problems. In this thesis, we use the SMC methods only for the nonlinear state estimation problem, however, it can also be used for the nonlinear parameter estimation problem. In order to demonstrate the new methods in the general nonlinear non-Gaussian case, we compare Sequential Monte Carlo (SMC) methods with the Ensemble Kalman Filter (EnKF) by performing data assimilation in nonlinear and non-Gaussian dynamic systems. The models used in this study are referred to as state-space models. The Lorenz 1963 and 1966 models serve as test beds for examining the properties of these assimilation methods when used in highly nonlinear dynamics. The application of Sequential Monte Carlo methods to different fixed parameters in dynamic models is considered. Four different scenarios in the Lorenz 1063 [sic] model and three different scenarios in the Lorenz 1996 model are designed in this study for both the SMC methods and EnKF method with different filter siz
Discipline: Natural Resources & Environmental Studies
Date added: 2017-03-30T17:04:08.893Z

Title: Plasticity in selection strategies of woodland caribou ( Rangifer tarandus caribou) during winter and calving.
Contributors: David D. Gustine (author), Katherine Parker (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: Woodland caribou may be an important indicator' or focal species for management agencies because they require large areas to persist and are sensitive to both direct and indirect forms of disturbance. Prior to industrial development in northern regions, it is important to acquire baseline information on areas that are important to local 'herds' as well as to identify physiological and ecological mechanisms of resource selection. I used global positioning system (GPS) data from caribou {Rangifer tarandus caribou), wolves {Canis lupus), and grizzly bears {Ursus arctos), and satellite imagery, resource selection functions, and cause-specific mortality data from 50 caribou neonates to define calving and wintering areas of woodland caribou in northern British Columbia. I identified scale-dependant mechanisms of selection relative to predation risk (calving, summer, winter, and late winter) and forage availability (calving and summer), and energetic costs of movement (winter and late winter) at 2 spatial scales, and quantified the variation in responses to these mechanisms among individual caribou. In all seasons, caribou selected habitats in a hierarchical fashion, and exhibited high variation among individuals. Three unique calving areas, or calving strategies, were defined for the Greater Besa Prophet area; each calving area had different attributes of risk and forage. During calving, spatial separation from areas of high wolf risk was important to parturient females as was access to areas of high vegetative change (i.e., forage quality); animals made trade-off decisions between minimizing the risk of predation and securing forage to address the high nutritional demands of lactation. Calf survival through the first 2 months of life ranged from 54% in 2002 to 79% in 2003. A total of 19 of 50 neonates died during the summers, of which 17 were by predation: wolverines (age of calves <14 d) and wolves (age of calves >18 d) each killed 5 calves. Movements away from calving sites (>1 km) peaked during the third week of life and increased the odds of a neonate surviving by 196%. These movements coincided with a change in vegetative phenology and the high energetic demands of lactation. During winter and late winter, minimizing the energetic costs of movement was the most important parameter in the selection of resources at a smaller spatial scale defined by seasonal movement, whereas Individual caribou showed increased sensitivity to the components of risk at a larger scale of the home range. Variation in the selection of resources by individuals was high, but some similarities facilitated using pooled use/availability data to model resource selection. These pooled models, however, collapsed important biological variation in the selection of resources, limiting biological interpretation of selection models. Variation in the selection of resources among individuals (i.e., plasticity) during all times of the year may be an important life-history strategy for woodland caribou to decrease their predictability on the landscape to major predators. Identifying and maintaining this variation within selection strategies is an important step towards determining the ability of caribou populations to persist in the presence of environmental and anthropogenic disturbance.
Discipline: Natural Resources & Environmental Studies
Date added: 2017-03-30T16:59:03.064Z