Ecological Restoration - Theses, Dissertations, and other Required Graduate Degree Essays

Receive updates for this collection

Restoration of an urban creek water quality using sand and biochar filtration galleries

Date created: 
2018-12-17
Abstract: 

Stormwater runoff from parking lots often contains a variety of elements and compounds in different forms and concentrations that may pose risks to biota in receiving aquatic systems. Heavy metals including copper (Cu) and zinc (Zn), and polycyclic aromatic hydrocarbons (PAHs) are of particular concern in such runoff due to their prevalence, toxicity to aquatic organisms and persistence in the environment. The ability of a commercially available biochar to remove pollutants of concern through column treatments was assessed in this research. Factors including the pollutant’s concentration, total organic carbon (TOC), pH, and biochar particle size were considered. The biochar used in this study showed a significant heavy metals and PAH removal ability compared to sand, qualifying it as a potential substitute for sand in urban structural best management practices. Maximum percentage removal using biochar followed the order of naphthalene (NAP) > Zn > Cu. Regarding Cu and Zn removal, small biochar exhibited higher removal efficiency compared to medium biochar. In terms of NAP removal, both small and medium biochar exceeded sand with a five-fold percentage removal. However, biochar of different particle sizes had the same removal percentage.

Document type: 
Graduating extended essay / Research project
File(s): 
Supervisor(s): 
Ken Ashley
Department: 
Environment: Ecological Restoration
Thesis type: 
(Project) M.Sc.

Marsh resiliency strategies in the face of sea-level rise: Pilot project opportunities for Fraser River delta tidal marshes

Date created: 
2020-05-07
Abstract: 

Coastal wetlands are naturally resilient to changing sea levels; however, as rates of sea-level rise increase, the interaction between changing sea-level and ongoing human impacts will be a major driver in future coastal tidal marsh stability. My goal is to provide decision makers with recommendations to increase the resilience of the Fraser River delta front tidal marsh communities over the twenty-first century. I conducted a literature review to (1) examine the current knowledge base regarding effects of sea-level rise on tidal marshes and (2) identify current ecosystem-based adaptation strategies for increasing tidal marsh resilience to sea-level rise. Based on this review, recommendations are made for strategies that could be used to increase tidal marsh resilience in the Fraser River delta. Recommendations include (1) initiating delta-wide marsh accretion modeling to assess tidal marsh vulnerability under possible sea-level rise scenarios and (2) implementing sediment augmentation pilot projects for both direct (e.g., layered sediment lifts) and indirect (e.g., mud motor) sediment augmentation strategies to test ecosystem based adaptive management strategies as part of an adaptive management framework.

Document type: 
Graduating extended essay / Research project
File(s): 
Supervisor(s): 
Ken Ashley
Department: 
Environment: Ecological Restoration
Thesis type: 
(Project) M.Sc.

Nanaimo River Estuary Restoration: An Assessment of Berm Removal on Benthic Macroinvertebrates in Tidal Channels

Date created: 
2016-04-16
Abstract: 

Macroinvertebrates in two berm-impacted tidal channels (Site A and Site B) were compared to a natural channel (Site C) to determine short-term response to berm removal restoration using a BACI study design. Multivariate analysis indicates that the benthic community composition shifted from before berm removal to after berm removal conditions but not in a predictable organized way. Total abundance was highest at Site A in both conditions (before and after berm-removal). Invertebrate diversity was similar and low among sites. Biomass was highest at Site C. Organic matter percentage was highest at Site C in both conditions and it appeared to increase in Site A and Site B after berm removal. Silt & Clay (>0.0063mm) were statistically different in Site C compared to Site A and Site B although very fine sand was the highest in percentage among sites and in both conditions. Berms affect channel and benthic invertebrate dynamics; time and more research are needed to fully restore the Nanaimo estuary.

Document type: 
Graduating extended essay / Research project
Supervisor(s): 
Ruth Joy
Department: 
Environment: Ecological Restoration
Thesis type: 
(Project) M.Sc.

A mitigation plan for salmonid spawning habitat in the Lower Seymour River, North Vancouver

Author: 
Date created: 
2018-04-19
Abstract: 

The Seymour River is a mountainous river located in North Vancouver. Over the past century, this river has been subjected to many anthropogenic activities that have cumulatively altered the natural flow and sediment regime. The Seymour Falls Dam, located in the middle of the watershed, intercepts gravel transport from the upper watershed into the lower reaches. This combined with the intense channelization within the lower 4 km of the river, which has created conditions incapable of gravel deposition and retention, has led the lower reaches to become gravel deficient. This gravel deficiency has caused the degradation of traditional spawning grounds of chum (Oncorhynchus keta), and pink salmon (Oncorhynchus gorbuscha). This study aims to: 1) determine if there is a gravel deficiency for chum and pink salmon spawning in the lower 1.5 km reaches and, 2) provide recommended mitigative treatments of gravel addition to increase suitable spawning area, and therefore increase salmon productivity of the Seymour River. A site assessment was conducted on the lower 1.5 km of the Seymour River and included sampling of the five key parameters that define spawning habitat (i.e., water depth, velocity, dissolved oxygen, water temperature and substrate). A particular focus was given on analysing the substrate as it was expected to be deficient for spawning due to the predetermined conditions in the watershed such as the dam and the channelization. Results of the site assessment confirmed that substrate is a limiting factor for chum and pink salmon spawning in this area as the bed surface is composed of large cobbles and boulders too large for these specific species to move to dig a redd. Therefore, a mitigation plan of gravel addition is proposed to increase spawning habitat and conserve these salmon runs.

Document type: 
Graduating extended essay / Research project
File(s): 
Supervisor(s): 
Ken Ashley
Department: 
Environment: Ecological Restoration
Thesis type: 
(Project) M.Sc.

An ecological restoration plan for a weedy field at The University of British Columbia Okanagan

Author: 
Date created: 
2019-04-15
Abstract: 

Grassland ecosystems are rare, in decline, and support a multitude of at-risk species in British Columbia. At the University of British Columbia Okanagan in Kelowna BC, a 3.3 ha site at the entrance of the campus is outlined as Okanagan grassland in campus design plans but currently lacks native bunchgrass communities. The goal of this restoration plan is to return grassland plant communities to the site despite the pervasiveness of noxious weeds. I characterised site conditions through soil and vegetation surveys. Restoration recommendations include managing noxious weeds through mowing, hand-pulling and some herbicide application. The site will be replanted with bunchgrass vegetation, two pockets of ponderosa forest, and two types of shrub communities. A walking path, signage, and two xeriscape gardens will also be included to control human use of the landscape. Long-term monitoring will be incorporated into classroom curricula to tie monitoring to learning opportunities.

Document type: 
Graduating extended essay / Research project
File(s): 
Supervisor(s): 
Miranda Hart
Department: 
Environment: Ecological Restoration
Thesis type: 
(Project) M.Sc.

Alaksen National Wildlife Area: Reservoir suitability for the introduction of the endangered Western Painted Turtle

Author: 
Date created: 
2019-04-16
Abstract: 

Alaksen National Wildlife Area located in Delta, BC is home to freshwater species in the former tidal marsh. The current agricultural landscape has left a legacy of high concentrations of heavy metals, trace amounts of organochlorine pesticides, and excess nutrients within the sediments and water of the brackish Fuller and Ewen Reservoirs. Arsenic and phosphorous exceeded Canadian water quality guidelines, while arsenic, chromium, copper, iron, manganese, nickel, and phosphorus exceeded sediment quality guidelines. There were trace pesticides known to be endocrine disrupters detected in the water and sediment, and combined low level toxicity effects are a concern. A preliminary ecological risk assessment on the metals was completed and the results indicate that there is a possibility of adverse effects for benthic invertebrates, but negligible risk for endangered Western Painted Turtles. However, compounding all the ecosystem stressors along with rising sea levels leads ANWA not an ideal place to introduce this species.

Document type: 
Graduating extended essay / Research project
File(s): 
Supervisor(s): 
Vicki Marlatt
Department: 
Environment: Ecological Restoration
Thesis type: 
(Project) M.Sc.

Restoring hydro-impacted wetlands for secretive marsh birds

Author: 
Date created: 
2019-04-17
Abstract: 

Secretive marsh birds can be difficult to detect and are dependent on wetlands, leaving them vulnerable to wetland loss or alteration. This study examines the influence of management-altered hydrological regimes on five secretive marsh bird species in the West Kootenay and Columbia Wetlands in British Columbia, Canada. Focal species occupied wetlands with less frequently altered hydrological regimes more often and in greater numbers. Occupancy models suggested that woody vegetation, tall vegetation, and open water are important drivers of occupancy for these species. Wetlands most frequently experiencing heavily altered hydrological regimes had more open water and less tall vegetation, both of which were negatively associated with wetland occupancy. Water management operations may be promoting altered vegetation communities within these wetlands, in turn promoting lower occupancy of secretive marsh bird species. Restoration recommendations include: prioritizing lower elevation wetlands, limiting woody vegetation encroachment, and experimentally restoring the hydrological regime of affected wetlands.

Document type: 
Graduating extended essay / Research project
File(s): 
Supervisor(s): 
David Green
Department: 
Environment: Ecological Restoration
Thesis type: 
(Project) M.Sc.

The effects of tree thinning and broadcast burning on the quality of ungulate winter range: A case study within a southern interior forest in British Columbia

Author: 
Date created: 
2018-04-20
Abstract: 

Food limitation on ungulate winter range (UWR) has been a suspected factor in the regional declines of Odocoileus hemionus (mule deer) in the Pacific Northwest. Accordingly, enhancing browse resources in this critical habitat is increasingly recommended. At a dry forest site in Southeast B.C. called Fiva Creek (IDF dm1), I investigated the effects of two commonly prescribed methods for enhancing browse production: tree thinning and prescribed burning. Treatments were implemented between 2005–2008 and included three levels of thinning (all burned) and control areas (uncut and unburned). The response variables I measured included browse cover, canopy closure, security cover, visibility, and pellet abundance. I also evaluated browsing pressure on the indicator plant, Saskatoon (Amelanchier alnifolia). Using linear mixed-effects ANOVA tests, I assessed how thinning (with follow-up burning) influenced forest and vegetation properties. There was no evidence of a treatment effect on browse production; however, browsing pressure was very high across the site (i.e., > 80% of A. alnifolia twigs showed evidence of browsing). Additionally, canopy cover was below recommended levels in all thinned treatments. My results suggested that restoration treatments actually diminished the quality of UWR at Fiva Creek. Further investigations are needed to develop effective UWR restoration methods.

Document type: 
Graduating extended essay / Research project
File(s): 
Supervisor(s): 
Douglas Ransome
Department: 
Environment: Ecological Restoration
Thesis type: 
(Project) M.Sc.

Investigating regeneration in a raised ombrotrophic bog after peat extraction

Author: 
Date created: 
2019-04-12
Abstract: 

Burns Bog is a raised ombrotrophic bog in Delta, British Columbia and faced with myriad disturbances. This study is focused on the impact and restoration of peat extraction by the Atkins-Durbrow Hydropeat method. Depth to water table, relative abundance and distribution of vegetation, and the degree of peat decomposition at consistent-depth intervals were investigated to elucidate the status of passive and active ecological restoration in three fields previously harvested for peat approximately one decade apart and compared to a fourth unharvested field. Summary statistics, Redundancy Analysis, and regression were used to compare restoration status and trends in hydrology, vegetation composition, and peat accumulation. A lag period between cessation of harvest and implementation of restoration, coupled with rapid anthropogenic climate change, serve as impediments to restoration here. Intervention in the form of improved rainfall retention, assisted recolonization, and the introduction of nurse species are recommended to improve bog function and resiliency.

Document type: 
Graduating extended essay / Research project
File(s): 
Supervisor(s): 
Ken Ashley
Department: 
Environment: Ecological Restoration
Thesis type: 
(Project) M.Sc.

Using 10-years of population monitoring data to assess breeding productivity of the Oregon Spotted Frog (Rana pretiosa)

Author: 
Date created: 
2018-04-17
Abstract: 

Relationships between changing environmental variables and amphibian populations have been understudied. Yet, alterations to temperature and precipitation have been suggested as contributors to the decline of some pond-breeding species, such as the Oregon Spotted Frog (Rana pretiosa). R. pretiosa has been classified as the most endangered amphibian within Canada, yet the cause for its decline is unknown. Therefore, this paper examined associations between temperature and precipitation and R. pretiosa population trends using a 10-year data set from two breeding populations in the Lower Mainland of British Columbia. Timing of oviposition was positively related to higher temperature and increased precipitation within both populations (p<0.05). No statistical relationship was determined between egg mass productivity and temperature of precipitation; however, this paper proposes that further research, consistent protocols and longer study periods, is mandated to determine environmental variables as a possible predictor of population success. This paper recommends the evaluation of breeding success through survivorship studies, as such methods provide insight into productivity as the primary determinant for population recruitment. Further, ecological restoration efforts can be implemented to help ameliorate negative consequences climate change poses on reproductive success.

Document type: 
Graduating extended essay / Research project
File(s): 
Supervisor(s): 
Leah Bendell
Department: 
Environment: Ecological Restoration
Thesis type: 
(Project) M.Sc.