Search results
- 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
- Date added
- 2019-07-09T18:39:10.427Z
- Title
- Foraging ecology of woodland caribou in boreal and montane ecosystems of northeastern British Columbia
- Contributors
- Kristin Denryter (author), Katherine Parker (thesis advisor), Darwyn Coxson (committee member), Michael Gillingham (committee member), Roger Wheate (committee member), Rachel Cook (committee member), University of Northern British Columbia (Degree granting institution)
- Abstract
- Woodland caribou (Rangifer tarandus caribou) are an iconic species of boreal and montane ecosystems, but many populations are declining due to habitat alteration and associated changes in predator-prey dynamics. Summer forage, however, influences lactation, juvenile growth, pregnancy, and survival, thereby affecting individuals and populations. I used tame caribou (of three nutritional classes — lactating, non-lactating, yearling) as a habitat assessment tool, at 135 sites across northeastern British Columbia, to determine: food habits and selection; dry matter intake rates; diet quality; and daily nutrient intakes. My goal was to assess the suitability of nutritional resources in boreal and montane plant communities to support energy and protein requirements of caribou during summer. Caribou were highly selective foragers. Deciduous shrubs were the primary summer forage of caribou; forbs, lichens, and mushrooms were secondary dietary items. Intake rates by caribou increased with increasing bite masses and quantities of accepted forage biomass (vegetation species used proportionately more than or equal to availability). Caribou achieved highest intakes at sites with an abundance of selected deciduous shrubs (e.g., willow-alpine sites, young forests) that afforded large bite masses, whereas lowest intakes occurred where mean bite masses were small (e.g., dry alpine, nutrient-poor forests). Dietary digestible energy (DE) and protein (DP) content, intake rates, and foraging time varied across plant communities and among nutritional classes. Caribou increased foraging time, but could not compensate for low intake rates and some plant communities failed to provide caribou with adequate nutrient intakes to support nutritional demands for lactation and maintenance of body mass. Although highest nutrient intakes were associated with productive sites, predation risk and disturbance may constrain the nutritional benefits caribou can acquire from these sites. In a pilot study, I mapped foodscapes of DE and DP intakes for a herd of free-ranging boreal caribou. Caribou did not select for nutrient intakes, but other factors including food quantity, predation risk, and accuracy of spatial data layers, may have confounded my ability to isolate the role of nutrition in habitat selection. Insights from this study into the nutritional ecology of caribou during summer can better inform caribou conservation and management.
- Discipline
- Natural Resources & Environmental Studies
- Date added
- 2017-08-29T21:09:28.595Z
- Title
- A spatio-temporal analysis of trends in Northern Hemisphere seasonal snow-cover, 1971-2017
- Contributors
- Michael Ian Allchin (author), Stephen Dery (thesis advisor), Brian Menounos (committee member), Roger Wheate (committee member), Richard Kelly (committee member), Dezene Huber (committee member), University of Northern British Columbia (Degree granting institution)
- Abstract
- Seasonal snow-cover (SSC) substantially alters surface physical properties over the Northern Hemisphere (NH). It modulates processes within the energy and water cycles, thereby influencing climatology, hydrology, geomorphology and ecology. In spring and summer, snowmelt provides an essential resource for humankind. The identification, quantification and explanation of changing spatial and temporal distributions of SSC helps to predict future impacts on natural and human environments, and informs development of mitigation and adaptation strategies. Because SSC is spatially and temporally heterogeneous, meaningful estimation of trends in its distribution and duration is dependent on long records of remotely-sensed imagery. The Rutgers University Global Snow Laboratory and the United States’ National Oceanic and Atmospheric Administration provide the longest such archive (NOAA-Rutgers Snow Archive, NRSA), dating from 1966. However, several studies have raised questions about the credibility of the signs and magnitudes of trends derived from the NRSA, suggesting that they may be artifacts of technological improvements introduced in 1999. This dissertation improves the spatial resolution at which NH SSC extent and duration trends during the NRSA’s longest continuous section (since 1971) are reported, building on previous hemispheric and continental studies. It demonstrates that the magnitudes of area-related trends are sensitive to assumptions adopted when estimating SSC extent from the NRSA, and that these sensitivities vary spatially. The study assesses whether temporal trajectories of SSConset trends imply abrupt changes in 1999, particularly over more complex terrain, and finds no evidence of this. It also explores the broader climatological contexts of these trends, together with estimated departures from mean conditions. Evidence is presented at monthly intervals for causative chains linking advection of mid-tropospheric warming from lower to higher latitudes, consequent inception of climatologically novel airflows, and the incidence of significant SSConset trends of both signs. Earlier onset of snow-dominated conditions is found to be driven by augmented moisture advected from lower latitudes (in eastern Eurasia) or zonally from oceanic sources (in North America) over regional monthly mean 0°C isotherms. Delayed onset is associated with drier or warmer airflows. These findings support the interpretation that the NRSA-based trends are plausible within their spatial and temporal contexts.
- Discipline
- Natural Resources & Environmental Studies
- Date added
- 2020-05-27T22:24:31.691Z
- Title
- Managing old-growth forests for multiple ecosystem services
- Contributors
- Luizmar de Assis Barros (author), Ché Elkin (thesis advisor), Oscar Venter (thesis advisor), Roger Wheate (committee member), University of Northern British Columbia (Degree granting institution)
- Abstract
- Old-growth forest reserves offer the potential to facilitate the maintenance of multiple ecosystem services (ES), such as carbon storage, water and recreation, in managed landscapes. However, substantial challenges exist with regard to defining and identifying old-growth forests, and suitably locating priority areas for old-growth conservation. To address these issues, I developed a structure-based old-growth index using field and LiDAR metrics that allowed old-growth values to be estimated at a fine grain across a landscape. I then used a spatial prioritization tool to simulate old-growth reserves for multiple ESs. Using this framework I evaluated trade-offs between forest ESs including timber. This thesis contributes to the management of old-growth forests by providing a quantitative and repeatable framework to identify, assess and monitor old-growth values while indicating the scope for the establishment of old-growth reserves for multiple ESs.
- Discipline
- Natural Resources & Environmental Studies
- Date added
- 2020-05-28T19:54:19.361Z
- Title
- A framework for mapping cumulative threats and its application to Canada
- Contributors
- Kristen Hirsh-Pearson (author), Oscar Venter (thesis advisor), Tammy Klassen-Ross (chair), Chris Johnson (committee member), Richard Schuster (committee member), Roger Wheate (committee member), Pamela Wright (committee member), University of Northern British Columbia Natural Resources & Environmental Studies (Degree granting institution)
- Abstract
- Methods for cumulative threat mapping, such as the human footprint, have been rapidly developing to inform the management of biodiversity and ecosystem services. Here, I perform the first comprehensive literature review establishing what methods are used, what threats are mapped and where, and if threats or impacts are mapped statically or dynamically in time. From knowledge gained in the review, I compiled geospatial datasets in a geographic information system to map the first Canadian human footprint. Subsequently, I answer where the most intact and heavily threatened areas are, what the most prevalent threats in Canada are and assess the accuracy of the data through a technical validation. This thesis contributes to conservation science by highlighting where regional studies are lacking, which threats are not being captured, providing examples of how studies have managed dynamic timescales and mapped through to impacts, and provides key information for future conservation in Canada.
- Discipline
- Natural Resources & Environmental Studies
- Date added
- 2020-12-11T21:46:29.113Z
- Title
- Counter-mapping for conservation
- Contributors
- Timothy Liam Burkhart (author), Pamela Wright (thesis advisor), Philip Mullins (thesis advisor), Roger Wheate (committee member), University of Northern British Columbia (Degree granting institution)
- Abstract
- Counter-Mapping seeks to empower communities to overturn the power dynamics of mapping by sharing a visual representation of space in a way that is accessible to the public and that presents utility to community conservation goals. Within a participatory action framework in partnership with the Yellowstone to Yukon (Y2Y) Conservation Initiative and local First Nations and communities, I built a web-accessible spatial mapping ‘hub’ for the Peace River Break region of BC. Through interviews with conservationists, First Nations and other community members, I examined the pitfalls and barriers communities in the Peace region face with mapping and mapping technology for conservation, including the case study atlas itself. A GIS-facilitated conservation strategy can address and integrate multiple voices, views understanding of local conservation desires in the context of larger conservation visions such as Y2Y, but building a tool and engaging communities to use it pose very different, unique, challenges.
- Discipline
- Natural Resources & Environmental Studies
- Date added
- 2019-03-22T22:00:35.635Z
- Title
- Mapping wilderness character in the Muskwa-Kechika Management Area
- Contributors
- Lindi Anderson (author), Pamela Wright (thesis advisor), University of Northern British Columbia College of Science and Management (Degree granting institution), Katherine Parker (committee member), Roger Wheate (committee member)
- Abstract
- Wilderness is an abstract concept containing both an ecological component more generally referred to as naturalness, and a social/human component attributed with recreation; it varies geographically, culturally and jurisdictionally. This thesis focuses on a case study of the Muskwa-Kechika Management Area (M-KMA) in northern British Columbia, Canada where maintaining wilderness is central to the vision. Previous mapping within the M-KMA has focused on wildlife and resource values, whereas this thesis aimed to define and map the wilderness character of the M-KMA. This thesis assesses the current state of wilderness to potentially examine changes over time and to spatially compare wilderness with other uses such as resource potential. When wilderness character data are separated into categories (lower, moderate, high and very-high), 55% is represented in the very-high quality category and only 9% by the lower category. In addition, there is 26% overlap between high resource potential values and very-high wilderness values.
- Discipline
- Natural Resources & Environmental Studies
- Date added
- 2019-04-03T00:03:20.475Z
- Title
- An approach to remotely monitor glacier mass balance at seasonal to annual time scales, Columbia and Rocky Mountains, Canada
- Contributors
- Ben Mauri Pelto (author), Menounos Brian (thesis advisor), Matt Reid (chair), Shawn Marshall (committee member), Peter Jackson (committee member), Stephen Dèry (committee member), Roger Wheate (committee member), Gwenn Flowers (committee member), University of Northern British Columbia Natural Resources & Environmental Studies (Degree granting institution)
- Abstract
- My dissertation investigates glacier mass change in the Columbia and Rocky Mountains of British Columbia. In chapter one I discuss the importance of the cryosphere and glaciers, introduce the climate and glaciers of the study region, and outline the objectives and structure of this dissertation. Previous work established the feasibility of geodetic methods to accurately produce winter glacier mass balance and annual glacier mass balance. These studies demonstrate that geodetic surveys can be used to estimate mass balance during the accumulation season or for one glacier over a number of years. In chapter two, I refine these published methods to measure seasonal and annual mass balance for six glaciers within two mountain ranges from 2014–2018. I use synchronous field-based glaciological measurements, airbornelaser scanningsurveys (ALS) and satelliteimagery to quantify seasonal glacier mass change from 2014–2018. Chapter three reports on radar surveys I completed of the study glaciers, adding important observations to the global database of ice thickness. I use these observations and an existing flowline model, driven with observations of surface mass balance and glacier elevation to bias-correct ice thickness estimates for each glacier. Finally, I use the model to estimate ice thickness for all glaciers in the Columbia Basin and estimate total ice volume. Chapter four builds upon previous work which used surface topography, glacier mass balance, ice thickness, and ice velocity data to estimate ice flux at discrete glacier cross-sections. Previous efforts to infer the spatial distribution of mass balance have focused on glacier tongues. I expand upon this method, calculating surface mass balance between flux gates over the entire elevation range of three glaciers, over three years. I derive the altitude-mass balance relation and demonstrate that the relation can be accurately described with high-resolution elevation and ice flux data, and suggest that this method can be expanded for large-scale estimates. Chapter five summarizes the study’s major findings, highlights its limitations and discussed its broader implications. Finally, I make recommendations that will address knowledge gaps, and improve our understanding of changing glacier conditions and ability to model glacier dynamics.
- Discipline
- Natural Resources & Environmental Studies
- Date added
- 2020-11-23T23:57:46.676Z
- Title
- Using Burn-P3 to model wildfire probability and aid in management of northern boreal forests in the Teslin Tlingit traditional territory
- Contributors
- Derek Hall (author), Scott Green (thesis advisor), Roger Wheate (committee member), Marc-André Parisien (committee member), University of Northern British Columbia (Degree granting institution)
- Abstract
- Through community collaboration and engagement, wildfire risk was identified as a priority forest vulnerability in Teslin, Yukon, a Tlingit community of approximately 450 people. Guided by community-directed research, identifying areas of higher wildfire hazard in the Teslin Tlingit Traditional Territory (TTTT) was of interest to help support ecosystem-based planning. Using Burn-P3, a landscape-level wildfire modelling software, relative wildfire hazard was identified in the TTTT. Future projected climate change scenarios were run using the program, providing a range of future possibilities for consideration. Burn-P3 complements the experience and knowledge of community members who live in the TTTT and this information has already been used to support the development of ecosystem-based planning. It is clear that community forest management will need to incorporate wildfire risk moving forward. All land management in the community is now being viewed through the lens of wildfire risk, which is the greatest benefit of this project.
- Discipline
- NRES-Forestry
- Date added
- 2019-04-03T20:49:08.833Z