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Title: Wetland ecological risk assessment and management
Contributors: Ge Xu (author), Jianbing Li (thesis advisor), University of Northern British Columbia (Degree granting institution), Min Zhao (committee member), Ron Thring (committee member)
Abstract: Based on the traditional framework of wetland ecological risk assessment, this thesis proposed a new method by considering two major pollution types faced by wetlands, including heavy metal pollution and water eutrophication. Artificial neural network (ANN) method was applied to evaluate the eutrophication risk level, while an improved potential ecological risk index was used to estimate the risk of heavy metals in surface sediments. Then, Fuzzy set theory was used to combine the two risk levels to obtain a general risk level, which could be used for recommending appropriate risk management actions. The Sanyang Wetland in Wenzhou, China was used as a case study to demonstrate the proposed wetland ecological risk assessment method. This thesis indicated that the new framework of wetland ecological assessment could provide a risk level of objectives and give corresponding suggestions to decision making.
Discipline: NRES-Environmental Science
Content Model: info:fedora/ir:thesisCModel
Date added: 2018

Title: Systematic conservation planning in the Wild Harts Study Area
Contributors: Ian Curtis (author), Pamela Wright (thesis advisor), Chris Johnson (committee member), Katherine Parker (committee member), University of Northern British Columbia (Degree granting institution)
Abstract: The Wild Harts Study Area (WHSA) covers an ecological diverse area in northeastern British Columbia that is poorly represented by protected areas. Industrial expansion threatens to fragment the contiguous habitats found in the WHSA — reducing the ability of the area to perform important landscape functions at local and continental scales. I employed a systematic conservation planning approach to prioritize lands for conservation. The software MARXAN with integer linear programming (ILP) was used to produce optimal solutions for conservation, at the lowest cost, and to enforce principles of protected area design. Priority lands for conservation action were those that met science-based targets for a selection of ecological surrogates, displayed low edge-to-area ratios, and represented intact landscapes outside the influence of resource development. The finalized conservation portfolio produced in this research is meant to inform protected area planning in the WHSA.
Discipline: NRES-Environmental Science
Content Model: info:fedora/ir:thesisCModel
Date added: 2018

Title: Multi-layer perceptron - markov chain based geospatial analysis of land use and land cover change
Contributors: Lei Shen (author), Jianbing Li (thesis advisor), University of Northern British Columbia College of Science and Management (Degree granting institution), Roger Wheate (committee member), Jun Yin (committee member)
Abstract: This thesis study analyzed the land use and land cover (LULC) changes in Stoney Creek Watershed, BC, Canada using the combination of remote sensing, GIS and modeling approaches. The Object-Based Image Analysis (OBIA) tool in PCI Geomatica 2017 software was applied to generate unsupervised classification LULC maps using Landsat TM and OLI images of the years 1986, 1999 and 2016. Various band ratio were computed to improve different classification results. Esri ArcMap 10.5 was used to produce all the LULC maps for subsequent modeling. A modeling method using Multi-layer perceptron (MLP) neural network and Markov Chain (MC) was performed to predict LULC changes in 2026, using hard and soft prediction results. The outcomes of this study could provide valuable information of LULC patterns and dynamics for supporting both environmental and economic development in this area.
Discipline: NRES-Environmental Science
Content Model: info:fedora/ir:thesisCModel
Date added: 2019

Title: Hydro-climatological Trend Analysis and Influences on the Discharge in the Elk River Watershed, Southeast British Columbia
Contributors: Krisitna Simone Anderson (author), Philip Owens (Thesis advisor), University of Northern British Columbia College of Science and Management (Degree granting institution), Stephen Déry (Committee member), John Rex (Committee member)
Abstract: Hydro-climatological modelling in mountainous environments is difficult due to topographic and climatic variability. Therefore, observed data (1970-2009) were used to assess trends in the Elk River watershed, a region experiencing growth of its open-pit coal mining industry. The Mann-Kendall trend test identified a decrease in snow throughout the watershed, small increase in rain, and overall decrease in northern precipitation. Moreover, mid-basin increase in temperature was detected. An increase in the Fording River winter discharge, counteracted the summer decrease in total watershed discharge from 1970-1989. Linear modelling identified baseflow, precipitation, and atmospheric teleconnection patterns as strong discharge drivers; whereas, the double mass curve identified a precipitation and discharge relationship change starting after 2007. Unfortunately, efforts to incorporate the Soil Water Assessment Tool proved unsuccessful for this watershed. Overall, these hydro-climatological trends were not as synchronized as expected likely due to other variables, such as watershed buffering capabilities and/or land-cover change.
Discipline: NRES-Environmental Science
Content Model: info:fedora/ir:thesisCModel
Date added: 2016

Title: Spatial and trophic biomonitoring of trace metals in aquatic environments following the Mt. Polley Mine tailings spill
Contributors: Aaron B. Zwiebel (author), Ellen Petticrew (thesis advisor), Phil Owens (thesis advisor), University of Northern British Columbia College of Science and Management (Degree granting institution), Sam Albers (committee member)
Abstract: A large (~25 M m3) copper-gold tailing spill occurred in 2014 at the Mt. Polley Mine, which released solid and liquid waste and caused a debris flow into nearby Polley Lake and Quesnel Lake. This study examined the spatial and trophic patterns of trace elements in water bodies impacted by the spill between April and November 2016. Concentrations of trace metals in biofilm, invertebrates, sediments, and water were measured and analyzed using DGT and ICP-MS. Trophic positioning of sampled organisms was established using invertebrate functional feeding groups, and stable isotope ratios. Spatial results indicated that copper and vanadium concentrations in biofilm and invertebrates at impacted environments regress significantly with distance to the spill. Trophic results show evidence of copper bioaccumulation and selenium trophic magnification in biofilm and invertebrates from impacted waters. These effects appear to have seasonal variations, with stronger trophic and spatial relationships during spring overturn of Quesnel Lake.
Discipline: NRES-Environmental Science
Content Model: info:fedora/ir:thesisCModel
Date added: 2019

Title: The movement of marine-derived nutrients from a salmon spawning river to a nursery lake
Contributors: Jacob Duros (author), Ellen Petticrew (thesis advisor), University of Northern British Columbia College of Science and Management (Degree granting institution), Samuel Albers (committee member), Svein Vagle (committee member)
Abstract: Salmon play a key role in the redistribution of marine-derived nutrients (MDNs) in aquatic and terrestrial ecosystems. Research conducted on the movement and storage of MDNs in aquatic systems throughout the Pacific Northwest seem to vary in whether MDNs have a beneficial, neutral, or detrimental impact. Using Horsefly Bay (Quesnel Lake), the mechanism and driving factors for the delivery and dispersion of MDNs were evaluated. Higher concentrations of marine-derived nitrogen and carbon were found to enter this nursery system in the fall spawning period. However, due to the increased water discharge, it was found that the load of marine-derived nitrogen and carbon was higher during the spring freshet study period. These increases in MDNs were found to correlate with chlorophyll-a and fluorescence levels which indicate increases in productivity. Increased production can support the growth and survivorship of juvenile salmon rearing in this nursery system through bottom-up trophic transfer.
Discipline: NRES-Environmental Science
Content Model: info:fedora/ir:thesisCModel
Date added: 2017

Title: Growth release and carbon storage of residual live trees in a mountain pine beetle (MPB) attacked lodgepole pine stand in northern British Columbia
Contributors: Jesse McEwen (author), Art Fredeen (thesis advisor), Tom Pyker (thesis advisor), Paul Sanborn (committee member)
Abstract: Carbon (C) storage in residual live lodgepole pine trees in northern BC at Kennedy Siding was measured 11 and 12 years after a severe mountain pine beetle (MPB) epidemic. Kennedy Siding eddy covariance (EC) measurements showed that the net ecosystem productivity (NEP) was quick to recover C sink status. In this study, measurements of heights and diameters of 160 residual live lodgepole pine trees and a subset of 60 tree cores were used to calculate residual tree stem C-storage in 2017 and 2018 (36.01 and 26.71 g C m-2 yr-1 respectively). Dendrochronology analyses indicated that residual pine trees released on average 392% in the decade following versus the decade prior to MPB-attack. Stem C-storage was strongly and positively correlated with ECNEP measurements (R2=0.77) and percent downed canopy trees (R2=0.837), suggesting that growth release of residual trees was likely driven by improvements in resources (e.g. light, moisture, nutrient).
Discipline: NRES-Environmental Science
Content Model: info:fedora/ir:thesisCModel
Date added: 2019

Title: Remediation of oil-based drill cuttings using low-temperature thermal desorption
Contributors: Huan Liu (author), Jianbing Li (Thesis advisor), Min Zhao (Thesis advisor), University of Northern British Columbia College of Science and Management (Degree granting institution), Ron Thring (Committee member)
Abstract: Drill cuttings are generated during the exploration and extraction of oil and natural gas. Due to the use of oil-based muds (OBMs) during drilling process, large amounts of oil-based drill cuttings (OBDCs) are produced. Such hazardous waste contains a relatively high content of petroleum hydrocarbons (PHCs). The effective removal of PHCs from OBDCs has attracted widespread attention since oil contaminants have severe impacts on the plant and animal ecosystem including human health (e.g., carcinogenesis and mutagenesis). Low-temperature thermal desorption (LTTD) treatment which both achieves relatively complete PHCs removal and keeps soil health at the maximum extent represent a feasible and promising method for the remediation of OBDCs. In this study, a bench-scale apparatus was used for the LTTD treatment of OBDCs with different PHCs contents... .
Discipline: NRES-Environmental Science
Content Model: info:fedora/ir:thesisCModel
Date added: 2017

Title: Forecasting spring freshet events in the Kiskatinaw River basin, British Columbia
Contributors: Hunter E. Gleason (author), Stephen Déry (thesis advisor), University of Northern British Columbia College of Science and Management (Degree granting institution), Michael Gillingham (committee member), John Rex (committee member)
Abstract: Incorporating climate information into hydrologic streamflow forecasts has allowed for significant advancement in the ability to predict seasonal streamflow. The City of Dawson Creek (CDC), BC, has depended on the Kiskatinaw River (KR) as its sole source of municipal water for over 60 years. Hydro-meteorological changes in the KR along with increasing population and growing industry have put stress on the CDC water supply. In this study regional surface climate observations aggregated over the winter accumulation period (15 November–25 March) integrated with global circulation indices were input into a series of regression models providing spring runoff predictions in the KR. The surface climate observations, indices of global circulation and snow cover provided good predictability of both cumulative streamflow timing and volume in the KR. This study provides the CDC with a tool for better informed releases and withdrawals from the KR during the spring freshet.
Discipline: NRES-Environmental Science
Content Model: info:fedora/ir:thesisCModel
Date added: 2018

Title: A high-resolution snow distribution on alpine catchments over Southern Columbia mountains
Contributors: Hamidreza Shams (author), Jueyi Sui (thesis advisor), University of Northern British Columbia College of Science and Management (Degree granting institution), Jiangbing Li (committee member), Liang Chen (committee member)
Abstract: Snow plays an important role on the hydrological cycle of watersheds in cold regions. Predicting timing and magnitude of snow accumulation and ablation is necessary for water management in different sectors. A spatially distributed snow model (SnowModel) is chosen for our research, which is forced by meteorological data provided from automated weather stations. SnowModel is evaluated for two watersheds in southeast of BC. Two consecutive year (2006-2008) are selected for the calibration and validation processes. Simulated snow depth and snow water equivalent (SWE) are compared with observed data from snow pillows. Two error factors of Nash-Sutcliffe Efficiency Index, and R-squared show 0.96, 0.98 values in accumulation period and 0.87, 0.86 for ablation period, respectively. Spatially distribution of snow depth and SWE over domains also are discussed. In general, SnowModel is able to estimate the accumulated snow depth and SWE in alpine areas in a high level of accuracy.
Discipline: NRES-Environmental Science
Content Model: info:fedora/ir:thesisCModel
Date added: 2019

Title: Sediment-associated contaminant transport and storage dynamics in the Quesnel River from the Mount Polley Mine disaster
Contributors: Richelle Sussbauer (author), Hossein Kazemian (Thesis advisor), Philip Owens (Thesis advisor), University of Northern British Columbia College of Science and Management (Degree granting institution), Samuel Albers (Committee member), Kerry Reimer (Committee member), Ellen Petticrew (Committee member), Marcel van der Perk (Committee member)
Abstract: In August 2014, the tailings storage facility of the Mount Polley copper-gold mine was breached releasing ~25 million m3 of tailings water and solids into Polley Lake and Hazeltine Creek, which scoured local overburden (1.2 million m3), and deposited these materials in Quesnel Lake. This study examined temporal and spatial movements of sediment-associated elements in Quesnel River, downstream of the lake, between August 2014 and August 2015. Suspended river sediment was collected using active and passive samplers (a continuous-flow centrifuge and time-integrated samplers), while discrete bed sediment was collected using a re-suspension technique. Results indicated elevated trace element levels, especially copper, with significant differences between element concentrations at the upstream site, closer to the breach, compared to downstream sites. Contamination indices and comparison to sediment quality guidelines indicated contamination was present in the river and varied seasonally predominantly driven by Quesnel Lake’s autumnal cooling and overturns.
Discipline: NRES-Environmental Science
Content Model: info:fedora/ir:thesisCModel
Date added: 2017

Title: Exploring Indigenous-led collaborative stewardship in a watershed context
Contributors: Kate Hewitt (author), Margot Parkes (thesis advisor), Scott Emmons (committee member)
Abstract: This research explores collaborative stewardship on a watershed scale and how local insight can assist in shaping collaborative approaches to culturally appropriate stewardship. The Cheslatta Carrier Nation (Cheslatta) have called the upper Nechako watershed home since time immemorial. They enjoyed a self-sustaining and peaceful existence until forced to leave when the waters started rising as their shores were flooded to create a reservoir. Regardless of adversity, Cheslatta have worked with passion and tenacity to restore the health of the upper watershed and the well-being of their people. Guided by Indigenous research approaches and appreciative inquiry, this research reviewed literature, documents and interviews with residents of the upper Nechako. The gathered data was then analyzed and themes were identified. The themes identified offer insights into local perspectives on stewardship, pointing especially to the ways reconciliation and community well-being can all be enhanced through cooperative and collaborative methods.
Discipline: NRES-Environmental Science
Content Model: info:fedora/ir:thesisCModel
Date added: 2019

Title: Bioremediation of drill cuttings and petroleum-contaminated soil using biosurfactant-enhanced soil washing, biostimulation, and bioaugmentation
Contributors: Ibukun Oluseyi Olasanmi (author), Ron Thring (thesis advisor), University of Northern British Columbia (Degree granting institution), Jianbing Li (committee member), Daniel Erasmus (committee member)
Abstract: Innovative technologies to combat environmental pollution are a significant part of sustainability research due to their increasing economic and environmental impact. The present biological process-based research study described herein was conducted in three phases. It investigated the effects of rhamnolipid-enhanced soil washing (phase 1), bioremediation treatment using indigenous microorganisms (phase 2), and the effect of four specific environmental and nutritional conditions (phase 3) on the biodegradation of petroleum hydrocarbons (PHC) in drill cuttings and petroleum-contaminated soil obtained from sites in northeastern British Columbia. For phase 1, maximum PHC reduction recorded for total petroleum hydrocarbon (TPH) and the petroleum hydrocarbon fractions- F2, F3 and F4 fractions was 58.5%, 48.4%, 63.5% and 59.8% respectively for petroleum-contaminated soil, and 76.8%, 85.4%, 71.3% and 76.9% respectively for drill cuttings. In phase 2, maximum PHC reduction of TPH, F2 and F3 fractions was 94.9%, 98.8% and 94.0% respectively for petroleum-contaminated soil and 82.6%, 94.9% and 59.5% respectively for drill cuttings following 50 days of rhamnolipid-mediated biodegradation treatment. Results from experiments conducted in phase 3 confirmed the importance of oxygen availability in biodegradation and indicated the inhibitory effects of excessive addition of biosurfactants and nutrients to hydrocarbon biodegradation treatments. Promising TPH degradation results were observed in conditions that normally slow down biodegradation. TPH degradation of 59.0%, 59.8% and 56.7% were observed in experiments conducted at an average temperature of ‒7.46 °C, and in waterlogged and air-tight conditions respectively. These results provide important insight on rhamnolipid-mediated biodegradation and indicate the high potential of rhamnolipid washing and bioremediation treatments as a combined approach to reduce PHC to levels within regulatory standards.
Discipline: NRES-Environmental Science
Content Model: info:fedora/ir:thesisCModel
Date added: 2018

Title: Examination of long-term soil development and phosphorus dynamics in a hypermaritime chronosequence, Calvert Island, British Columbia, Canada
Contributors: Lee-Ann Nelson (author), Paul Sanborn (thesis advisor), Barbara Cade-Menun (thesis advisor), University of Northern British Columbia (Degree granting institution), Ian J. Walker (committee member)
Abstract: This thesis examines soil development, phosphorus (P) dynamics and ecosystem succession in an aeolian sand dune chronosequence spanning 10,760 years on Calvert Island, in hypermaritime coastal British Columbia, Canada. After 100 years of soil development, thick forest floors have developed (~28 cm), and after ~3,500 years mature Podzols have formed with cemented placic and ortstein horizons. With increasing soil age, mineral soil total P declines linearly and organic P forms become increasingly dominant, with glycerophosphates dominating organic horizons, and inositol hexakisphosphates and DNA dominating mineral horizons on the older sites. After 7,000 years, ecosystem retrogression – a long-term decline in biomass – is suggested by reduced tree basal area and a shift towards shrubby, more stress-tolerant species such as Pinus contorta var contorta and Tsuga mertensiana. Retrogression in the Calvert Island chronosequence is most likely caused by formation of cemented horizons and declining soil P reserves, though further investigation is needed.
Discipline: NRES-Environmental Science
Content Model: info:fedora/ir:thesisCModel
Date added: 2018

Title: Arsenic adsorption in aqueous solution and immobilization in soils and using hand warmers
Contributors: Zeyi Tong (author), Ian Hartley (Thesis advisor), Todd Whitcombe (Thesis advisor), Hualin Chen (Thesis advisor), University of Northern British Columbia College of Science and Management (Degree granting institution), Michael Rutherford (Committee member), William McGill (Committee member), Yubao Li (Committee member)
Abstract: Adsorption is a commonly used method for arsenic remediation. The adsorption and immobilization effectiveness of arsenic by soil particles and used hand warmers was studied. The adsorption effectiveness at equilibrium of soil particles in 10 ppm As(III) solution was: clay (77.70%) > silt (69.24%) > sand (41.35%). In 1000 ppm As(III) solution, 17.02 mg As(III) was adsorbed onto each gram of hand warmers at equilibrium, which was significantly higher than other adsorbents. For As(III) adsorption from aqueous solution, soil samples and hand warmers were well fitted to the pseudo secondorder model and the Freundlich model. After 8 weeks of soil incubation, the sequential extraction procedure data indicated the labile fractions of arsenic (F1 and F2) decreased with the addition of hand warmers. Meanwhile, the percentage of the most stable fraction, F5, increased. These results are valuable for the future application of used hand warmers as an adsorbent/amendment for arsenic decontamination.
Discipline: NRES-Environmental Science
Content Model: info:fedora/ir:thesisCModel
Date added: 2017

Title: Wind climatology of Quesnel Lake, British Columbia
Contributors: Hadleigh David Thompson (author), Stephen Dery (thesis advisor), University of Northern British Columbia College of Science and Management (Degree granting institution), Peter Jackson (committee member), Bernard Laval (committee member)
Abstract: Intermontane lakes are often enclosed by complex topography that creates difficulty in resolving the local and regional wind fields. Quesnel Lake, nestled into the western flank of the Cariboo Mountains in central British Columbia, is one such lake. This study examines the wind climatology of Quesnel Lake at three distinct spatial and temporal scales. Firstly, long-term wind data from meteorological stations bordering the Cariboo Mountains exhibit a cycle of calm and active periods throughout the year. Secondly, an environmentto- circulation synoptic climatology is presented that illustrates the large-scale atmospheric patterns that lead to strong wind events at the lake. Finally, the spatial and temporal variability of the near-surface wind field has been examined using an array of shore-based meteorological stations. The response of the wind field to synoptic forcing is found to be driven primarily by the orientation of the regional 800 hPa pressure gradient. iii
Discipline: NRES-Environmental Science
Content Model: info:fedora/ir:thesisCModel
Date added: 2019