Master of Science in Ecological Restoration Applied Research Projects | BCIT Institutional Repository

Master of Science in Ecological Restoration Applied Research Projects

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Blue carbon dynamics across the Metro Vancouver region
This research project aims to assess the carbon sequestration dynamics of three tidal marshes under different environmental conditions in the Metro Vancouver region. By identifying the site conditions that influence carbon sequestration, areas can be prioritized, and restoration activities can be adapted to increase or maintains the marsh’s ability to do so. This project was done in partnership with Parks Canada and will contribute to a larger study of ‘blue carbon’ across British Columbia. For this project, I collected sediment cores from the eastern portion of Boundary Bay in Delta, BC, Brunswick Point in Ladner, BC, and a constructed salt marsh in Tsawwassen, BC, to assess soil carbon content and carbon stocks. Porewater salinity, vegetation data and depth measurements were collected at these sites as well. Percent carbon content ranged between 3.98 ± 1.48% and 5.78 ± 5.93% between the three marshes and the marsh carbon stock ranged between 93.95 Mg C and 2,994.51 Mg C. Across the three marshes, core carbon stock for the high marsh cores was found to be significantly higher than the core carbon stock for the low marsh cores, suggesting that marsh zonation influences carbon stock. The data analysis and literature review determined that vegetation and porewater salinity had the greatest influence on a marsh’s ability to sequester and store carbon. The results indicate that the high marsh with low salinities and a diverse plant community have the highest carbon sequestration potential. As marshes with conditions similar to that of the Boundary Bay marsh as well as polyhaline marshes should be prioritized for restoration. These findings will aid in the development and implementation of restoration projects to increase a marsh’s ability to sequester carbon., blue carbon, tidal marsh, carbon stock, British Columbia, coastal management, restoration, marsh restoration
Breeding waterfowl use of restored wetlands in the Cariboo region of British Columbia
This study investigated effects of wetland size and emergent vegetation cover on breeding waterfowl and young at 12 restored wetlands in the Cariboo region of British Columbia. Repeated ground surveys were conducted throughout summer 2019 to determine total abundance, density and species richness of waterfowl. Surveyed wetlands varied in size and emergent cover. Large (16-19 ha) wetlands had greater breeding total abundance and lower breeding and brood densities than smaller wetlands. Total abundance of breeding waterfowl and young were highest when wetlands had less than 60% emergent cover. Previous studies suggest that high densities of waterfowl decrease young survival. Restorations created to benefit several species of breeding waterfowl may want to restore wetlands that are large (>16 ha) and have less than 30% emergent vegetation cover. These wetlands had higher total abundances and lower densities than other categories studied, however, certain species may depend on smaller wetlands which should be researched further., Cariboo region, wetland restoration, breeding waterfowl, emergent vegetation
A climate adaptation plan: Identifying thermal refugia for salmonids in the Tsolum River
Stream temperatures in the Pacific Northwest are increasing due to climate change, resulting in thermal stress for salmonids. Groundwater is a cooler source of water into streams, providing thermal refugia. The goal of this Applied Research Project was to identify groundwater input areas in the Tsolum River, using temperature loggers to trace the thermal signal of groundwater. A total of 28 water temperature loggers and 2 air temperature loggers were deployed within the watershed in the summer of 2019. Results showed that 12 sites may be influenced by groundwater input. Restoration/management actions such as riparian planting, gravel bar live staking, and restrictions on groundwater withdrawal are recommended to decrease stream temperatures. This study demonstrated that temperature loggers can be deployed within streams to identify areas of groundwater input. The identification of thermal refugia within the Tsolum River and other salmonid-bearing streams will help to protect salmonids from climate change impacts., climate adaptation, thermal refugia, Tsolum River, groundwater
Ecological restoration options for Clear Lake and South Lake (Riding Mountain National Park), Manitoba
Options for ecological restoration are discussed for the Clear Lake – South Lake complex of Riding Mountain National Park, Manitoba. This project consisted of a) a review of studies conducted on Clear Lake and South Lake and b) a stream water quality sampling program. The review of previous studies was to gain an in-depth understanding of historical processes which shaped Clear Lake and South Lake. Previous condition, current condition and ecological stressors are all identified based on literature from Riding Mountain National Park. The stream water quality sampling program identifies major sources of nutrients into Clear Lake. Ecological restoration options pertain specifically to the Clear Lake – South Lake complex. South Lake restoration options include supplemental planting, dredging and chemical treatments. A novel technique designed to disrupt wind driven nutrient loading is also discussed. These methods are designed to return the South Basin to a macrophyte dominated system. Addressing hypolimnetic oxygen deficiency, two forms of hypolimnetic aeration are discussed to improve water quality in Clear Lake including a ‘Full lift’ design as well as a Speece Cone. Three options regarding the isthmus and connectivity between Clear Lake and South Lake are examined including a fishway installation and a wattle fence installation.
An ecological restoration plan for a weedy field at the University of British Columbia Okanagan
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., Grassland, exotic plants, Noxious weeds, urban restoration, restoration plan
The effect of nitrogen fertilization on the physiology and morphology of Sphagnum capillifolium in an ombrotrophic bog
Degraded peatlands release 100-200 g-CO2 eqv. m-2 yr-1 in net emissions and account for more than 10% of global CO2 emissions. The success of bog restoration is dependent on creating suitable moisture conditions for the donor material to establish, propagate, and develop a new layer of Sphagnum that has hydrophysical and water retention properties similar to natural peatlands. Techniques to improve moisture retention during the transplant process and increase water holding capability of the restored Sphagnum layer have been identified as an area of bog restoration that requires more research. Samples were collected from plots fertilized with six different nitrogen treatments at Mer Bleue Bog in Ottawa, Canada. Net CO2 assimilation, fresh weight, dry weight, water content, and dissolved nutrient measurements were made to determine the potential effectiveness of incorporating nitrogen fertilization into the North American approach to peatland restoration. High levels of nitrogen fertilization exerted deleterious effects on individual morphology, growth density, water holding and retention capacity, CO2 assimilation, and nutrient dynamics and decomposition. Fertilization with 1.6 g m-2 yr-1 of ammonium has the potential to ameliorate water retention capacity through more robust individual morphology and denser growth patterns and increases carbon assimilation and photosynthetic capacity. The results indicate integrating low levels of ammonium fertilization into bog restoration techniques can potentially increase restoration success., water content, carbon dioxide assimilation, growth density, peatland restoration, ammonium, nitrate
The effect of time-since-burning and hand-pulling on the growth and stem density of Centaurea stoebe and Linaria dalmatica
Prescribed burning and hand-pulling are used to manage invasive plants but treatments can deferentially affect species. My objective is to determine the effect of time-since-burning and hand-pulling on stem density and growth of Centaurea stoebe (spotted knapweed) and Linaria dalmatica (Dalmatian toadflax). Prescribed burns occurred in March 2015 and 2016, while hand-pulling occurred in April and May of 2017. I conducted vegetation surveys in May, June, and July 2017. Growth rates differed among treatments and by species. Centaurea stoebe was not detected in the prescribed burn treatments. Hand-pulling increased stem density of C. stoebe, but individuals were smaller and 60% remained as basal rosettes compared to control. Linaria dalmatica were significantly taller in the burn treatments, and the stem density of L. dalmatica was greater in the prescribed burn and hand-pull treatments compared to control. The tallest L. dalmatica occurred in the 2-year post-burn site, indicating a time-since-burning interaction., invasive plants, prescribed burning, hand-pulling, Cetaurea stoebe, Linaria dalmatica
The effect of vegetation structure and abiotic variables on oviposition-site selection by amphibians
Assessing restoration success for pond-breeding amphibians frequently focuses on hydrology, water quality and vegetation, while neglecting the requirements of amphibians that use the restored areas for breeding. Both biotic and abiotic conditions can influence oviposition-site selection of amphibians that do not provide parental care. This study examines how vegetation structure and abiotic variables affect oviposition-site selection by amphibians. The goal of my study was to better understand the requirements of pond-breeding amphibians. In 2017, I surveyed egg masses in four ponds at the Sunshine Coast Botanical Garden in Sechelt, B.C. I identified 667 egg masses of four native amphibian species that varied in abundance and species richness among ponds. I recorded five biotic variables (i.e., vegetation cover, vegetation type, stem density, stem diameter, and canopy closure) and two abiotic variables (i.e., water depth and solar radiation) at egg-mass sites and random sites where no egg masses were detected. Logistic regression analysis with backward elimination revealed that stem count (p = 0.008) and water depth (p = 0.0001) significantly influenced oviposition-site selection. The results also showed that higher stem density and shallower water depth increased the likelihood of egg masses being present. My study indicated that quantifying stems in the water column characterized vegetation density better than estimating percent cover of vegetation. Shallow areas that have structurally complex vegetation might provide an advantage for the offspring by increasing refuge, food resources, and favourable thermal conditions for egg development. Hence, restoration projects could incorporate vegetation structure and shallow areas in their pond designs to potentially increase the abundance and diversity of amphibian communities, thereby contributing to successful restoration projects., ecological restoration, amphibians, oviposition, Rana aurora, Pseudacris regilla, Ambystoma gracile, Amystoma macrodactylum, vegetation structure, abiotic variables
Effects of Canada Goose (Branta canadensis) and Snow Goose (Chen caerulescens) herbivory on tidal marsh recession at the Westham Island Marsh
In the Fraser River Estuary of British Columbia, tidal marshes have been receding and converting into unvegetated mudflats since the 1980s. While there are many hypotheses for this recession, the effect of avian herbivory is poorly understood. This study assessed how Canada Goose (Branta canadensis) and Snow Goose (Chen caerulescens) herbivory affected cover of tidal marsh vegetation that was comprised mainly of three-square bulrush (Schoenoplectus pungens) in the Westham Island tidal marsh. I conducted two field-based exclosure experiments, marsh edge and mudflat, that used exclosure plots to reduce specific goose herbivory in a randomized block design. Each experiment consisted of four blocks each of which was comprised of four treatments: open to goose herbivory, excluded all goose herbivory, primarily excluded Canada Goose herbivory, or primarily excluded Snow Goose herbivory. The marsh edge experiment used exclosures centered on the vegetated edge of the marsh, while the mudflat experiment was conducted in the unvegetated mudflat and were transplanted with S. pungens. Based on results from July to October of 2020, percent cover of tidal marsh vegetation was about 20% lower in plots open to Canada Goose herbivory versus those that excluded geese. Snow Goose herbivory could not be accurately assessed as they arrived when S. pungens were dormant. Thus, deterring goose herbivory may be an important consideration for land managers in restoring tidal marshes. Additionally, I compared percent cover from drone-derived remote sensing to traditional ground-based visual estimates of percent cover of S. pungens in the tidal marsh. One per month, from July to October of 2020, I used a drone to take photos of the exclosures from the previous experiments, and used pixel counts to calculate the percent cover of S. pungens. I then used a t-test to compare the drone-derived percent cover to the ground-based estimates and found no significant difference (t = 0.58, p = 0.56). I then plotted a linear regression model and found a strong correspondence between both methods (R² = 0.99, p = 1.3e-139). So, remote sensing using drones appears to be an effective alternative to visual estimates of percent cover of tidal-marsh vegetation in the Westham island tidal marsh., Tidal marsh recession, Goose herbivory, Canada Goose, Snow Goose, Schoenoplectus pungens, Drones
Exploring the relative effects of different wetland restoration sites on functional connectivity for the northern red-legged frog (Rana aurora)
Amphibian species are globally at risk, with a leading cause of decline attributed to habitat loss and fragmentation. The northern red-legged frog (NRLF) is one such species and listed as a Species of Special Concern by the Species at Risk Act. The Sunshine Coast Wildlife Project is creating new wetland habitat on the Sechelt Peninsula. In this research, I provide a tool to explore the relative effects on the functional connectivity of different potential restoration sites. A habitat suitability model (HSM) was created to describe the landscape in terms of conductance, or ease of movement for NRLF. Using this conductance map, I analysed the functional connectivity between wetlands by using Circuitscape, a software grounded in circuit theory. Three potential restoration options were compared against the existing landscape. Of the three options, one had a much greater effect in increasing the overall wetlands and its connectivity to the existing network of wetlands., Functional connectivity, wetland habitat restoration, northern red-legged frog (Rana aurora), circuit theory, Circuitscape, habitat suitability model (HSM)
Factors limiting the expansion of black-tailed prairie dog colonies at their northern extent
Prairie dogs (Cynomys ludovicianus) are considered a keystone species due to their ecological role in maintaining the prairies. In Canada, they are federally listed as a threatened species. This study was conducted to identify the limiting factors to the expansion of prairie dog colonies in Grasslands National Park, Saskatchewan. I tested different hypotheses to compare landforms, vegetation, and soil characteristics in three treatments: consistently occupied (Consistent), inconsistently occupied (Inconsistent), and never occupied (Buffer) by prairie dogs. I sampled four prairie dog colonies (blocks) from 17 July 2019 to 28 August 2019 using a randomized complete block design. I used ANOVA to test variables for significant differences among treatments. My results showed that hills, water channel, shrublands, grass cover, shrub cover and vegetation height classes (>30 cm) were significantly higher (p <0.05) in Buffer compared to Consistent and Inconsistent. Shrubs and tall vegetation should be mowed down to enhance the expansion of prairie dog colonies for restoring their population., restoration, prairie dogs, Cynomys ludovicianus, colony expansion, barriers, habitat use
A historical marsh vegetation composition comparison between five Fraser River foreshore marshes
A full composition study of some key Fraser River foreshore marshes, Boundary Bay, Brunswick Point, Westham Island, Lulu Island, and Sea Island, had not been done in several decades, during which a large-scale marsh recession event occurred at two of the marshes. The vegetation composition is measured in this study with relation to soil water, soil pore water salinity, and elevation. The results in this study show a shift in the vegetation composition in some areas of the Lulu Island marsh, with the other marshes remaining relatively similar to historical data. The plant species’ tolerance to soil water, soil salinity, and elevation vary in each marsh, illustrating the need for individualized restoration plans for each marsh. Conserving and restoring these marshes is critical in light of the many changes in the Fraser River delta, including sea level rise, increased geese populations, altered sediment regimes, and urbanization., Fraser River, brackish marsh, salt marsh, vegetation composition, salinity, elevation
Hypolimnetic upwelling in coastal embayments of Lake Ontario; implications for restoration
Coastal wetlands are an important ecosystem in the Great Lakes basin, providing spawning grounds and warm-water refuge for numerous fish and benthic invertebrate species during cold water upwelling events. Urbanization along the northwestern shore of Lake Ontario has led to a depletion of coastal wetlands, replacing them with artificial embayments. Three artificial embayments, the Credit River estuary, and one coastal marsh in Mississauga, ON were studied to determine if the artificial embayments function as warm-water refuge during upwelling events. Temperature loggers were placed in each study site and temperature was recorded every 15 minutes from July to October 2017. Upwelling events were isolated from the data, and frequency, magnitude, and duration of upwelling was determined. Most study sites had a frequency of 4 upwelling events throughout the study period. The average duration of upwellings varied from 30 to 70 hours, and the average temperature change ranged from -7.1ᵒC to -11.9ᵒC. All of the study sites seemed to buffer upwellings by reducing the magnitude of temperature change and increasing the duration of upwelling events to varying degrees. These results will inform the creation of future wetlands, restoration of existing embayments, and conservation of Great Lakes coastal wetlands., ecological restoration, coastal embayments, coastal marsh, upwelling, warm-water refuge, Lake Ontario
Identifying temporal trends and mechanisms for successful reforestation on former agricultural land
This study investigates the outcomes of restoration efforts completed on retired agricultural land in Southwest Ontario. Sites acquired by the Nature Conservancy of Canada were planted to kickstart succession to native deciduous forests, but the results of the plantings are mixed. Analysis of soil conditions indicated that low levels of soil organic carbon were correlated to low water content and high density unfavourable for plant growth. Analysis of remotely sensed imagery was done to assess and compare vegetation cover to reference conditions at Walpole Island First Nation. Analysis revealed that successful restoration was dependent on multiple soil characteristics, but conditions correlated to higher total organic carbon favoured greater vegetation cover. Remote sensing data revealed that succession towards tree canopy development was accelerated compared to passive restoration, and a shaded understory was established approximately 8-12 years following restoration. Future work can expand on succession and the effects of other restoration treatments., Soil, Reforestation, NDVI, Agriculture, Restoration, Secondary succession
The impacts of exotic Typha on benthic invertebrate communities in the South Arm of the Fraser River Estuary
In recent decades, the exotic cattail Typha angustifolia and its hybrid Typha x glauca have invaded the Fraser River estuary. The impacts from this invasion on benthic macroinvertebrate communities, however, are yet to be studied. Macroinvertebrates play important roles in food chains, trophic dynamics, and nutrient cycling and are potentially at risk from this invasion. In this study, I compared the benthic invertebrate communities between exotic cattail stands and native vegetation stands at 25 paired sites. Sediment cores were analyzed for invertebrate abundance, biomass, and Shannon Wiener diversity index, and it was found that biomass and abundance were lower in exotic cattail when compared to native vegetation, however, there was no difference in diversity. Given the proximity to side channels, tidal inundation time would be a logical explanation for the differences in the benthic communities; however, it was not found to be a significant predictor. Given the invasive nature of exotic cattail and the correlations that were found, cattail should be removed in restoration projects where possible., Fraser River, Typha x glauca, Estuary, Invasive species, Typha angustifolia
Investigating regeneration in a raised ombrotrophic bog after peat extraction
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., Atkins-Durbrow Hydropeat method, Ditch blocking, Ecological restoration, Peat extraction, Raised ombrotrophic bog, Burns Bog

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