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

Master of Science in Ecological Restoration Applied Research Projects

Alaksen National Wildlife Area: Reservoir suitability for the introduction of the endangered Western Painted Turtle
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., © Darian Weber, 2019. All rights reserved. No part of this work covered by the copyright heron may be reproduced or used in any form or by any means – graphics, electronic, or mechanical including photocopying, taping, or information storage and retrieval systems – without written permission of the author., Western Painted turtles, ecotoxicology, risk assessment, agricultural reservoir, heavy metal, endocrine disruptors
Assessing the allelopathic effect of invasive phragmites australis on sida hermaphrodita and ammannia robusta; two species at risk in Southern Ontario
In Ontario, invasive Phragmites australis threatens to displace many species including the endangered species Sida hermaphrodita and Ammannia robusta. Germination and growth assays measured the effect of P. australis aqueous extracts from the leaves, rhizomes, and roots on S. hermaphrodita and A. robusta. Germination was inhibited by some of the treatments, but growth was not. The tissues inhibited germination differently for S. hermaphrodita (leaf> rhizome> root) compared to A. robusta (root> rhizome> leaf) indicating that the allelopathic effect was species-specific. However, the laboratory results show that allelopathic effects are weak. This result is consistent to the field study results showing an increase in S. hermaphrodita area and density over time. Results from this project inform management options by indicating which part of the plant needs to be targeted. In this case, all the tissues had some phytotoxic effects, indicating that biomass may need to be removed or long-term management implemented., Invasive Species, Species at Risk, Seed Germination, Seedling Growth, Allelopathy
Comparing soil nematode composition in bluebunch wheatgrass P. spicata root to the occurrence of invasive plants C. stoebe and L. dalmatica
The viability of native bunchgrass ecosystems throughout the PPxh BEC subzone and in Kenna Cartwright Park (KCP) in Kamloops B.C. are under threat by invasive plants. Once established, invasive plants are difficult to eradicate and can predominate the landscape. I collected soil samples from a relatively undisturbed bunchgrass reference site composed of native bluebunch wheatgrass (Pseudoroegneria spicata), and I collected soil samples from a bunchgrass site occupied by the invasive plants, spotted knapweed (Centaurea stoebe) and dalmatian toadflax (Linaria dalmatica), to compare the soil nematode communities. My results reveal differences in the community-level biodiversity and abundance of soil nematodes between sites. The Maturity Index and the Plant Parasitic Index indicate that the native bunchgrass site had a “Structured” soil food web and that the site occupied by invasive plants had a “Basal” soil food web. My results indicate soil nematodes are useful as bioindicators of soil properties and these data provide useful criteria to help prioritize sites for ecological restoration., Nematology, Invasive plants, Pseudoroegneria spicata, Biological indicators, Ecological restoration
Ecocultural restoration of a Coastal Root Garden on Tl’chés (Chatham Island), B.C.
Tl’chés is the Lekwungen name for the Chatham Islands — an archipelago located southeast of Victoria, British Columbia. Tl’chés is a central place in the traditional territory of the Lekwungen peoples, and today it is reserve land of the Songhees First Nation. This landscape was traditionally managed by prescribed burning and the cultivation of native plants. However, in the early 1950's, Lekwungen peoples left the archipelago, due to a lack of potable water and since then, the landscape has degraded drastically. The introduction of non-native plants has resulted in threats to the ecological, cultural resilience, and diversity of the landscape. My research focuses on developing a restoration plan for springbank clover in the coastal root garden. My restoration approach focuses on incorporating a Songhees-informed approach to restoration by integrating past practices and knowledge with the aim of answering: how to best restore the springbank clover population on Tl’chés?, Eco-cultural restoration, coastal root gardens, traditional ecological knowledge (TEK), Songhees First Nation, cultural keystone place (CPK)
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
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., Mule deer, ungulate winter range, thinning, prescribed fire, restoration ecology
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
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
Investigating the effect of salinity, elevation, redox potential, and geese herbivory on planting success in a Pacific Northwest salt marsh
The MacKay Creek Estuary, is a severely altered estuarine ecosystem located within an active international port in Vancouver, British Columbia. Several elevated salt marsh terraces were constructed as part of a larger restoration project within the MacKay Creek Estuary. Site visits conducted in 2018 revealed 75% of the terrace surface area failed to establish salt marsh vegetation. Significant difference in soil pore-water salinity, oxidation reduction (redox) potential and tidal elevation were found between vegetated and unvegetated portions of the terraces. Additionally, exclusion from Canada Geese (Branta canadensis) herbivory increased total percent cover and colonization of the adjacent unvegetated area. The combination of soil parameters and herbivory, as well as potential interactions between factors may be responsible for the lack of vegetation progression within the constructed salt marsh terraces at MacKay Creek Estuary., restoration, salt marsh, redox potential, pore-water salinity, MacKay Creek, Fraser River, estuary, Canada geese
Phytoremediation of contaminated soils
Phytoremediation poses an ecologically friendly and cost-effective alternative to other remediation methods such as chemical or thermal treatment. However, in contaminated sites such as retired oil wells and brine spills, it is common to have a co-contamination of salt and polyaromatic hydrocarbons (PAHs). The co-contamination of salt and PAHs may decrease the rate and effectiveness of bioremediation. Here we investigated the effect soil salinity has on the rate of phytoremediation, plant survivability and biomass. A 90-day greenhouse study was performed, growing alfalfa (Medicago sativa L.) in soils treated with varying salt (NaCl) concentrations in the presence of pyrene and benzo[a]pyrene. No significant differences were observed in the presence or absence of PAHs. Salt treatments has significant affects on plant biomass, nodulation, and successful germination., Bioremediation, Polyaromatic hydrocarbons, Alfalfa, Salt, Phytoremediation
Restoring a culturally eutrophic shallow lake: Case study on Quamichan Lake in North Cowichan, British Columbia
Quamichan Lake is a culturally eutrophic shallow lake located in North Cowichan on Vancouver Island in British Columbia. My research project examined the current trophic status and water quality of Quamichan Lake and investigated a number of watershed and in-lake restoration methods to return the lake back to mesotrophic (nutrient rich) conditions. Based on the data collected, Quamichan Lake is currently in a hypertrophic state caused by excess phosphorus inputs that leads to Cyanophyte phytoplankton species (cyanobacteria) to dominate during the summer. Eutrophication is both an environmental and human health issue as cyanobacteria algal blooms can disrupt the lake ecology and are toxic to most mammals. The goal of my research was to provide the Municipality of North Cowichan and Vancouver Island Health Authority with a comprehensive restoration plan to contribute to the restoration of Quamichan Lake and other lakes in southern Vancouver Island that are experiencing cultural eutrophication., © Kathleen E Moore, 2019. All rights reserved. No part of this work covered by the copyright heron may be reproduced or used in any form or by any means – graphics, electronic, or mechanical including photocopying, taping, or information storage and retrieval systems – without written permission of the author., Eutrophication, Limnology, Watershed Management, Cyanobacteria, Restoration
Restoring hydro-impacted wetlands for secretive marsh birds
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., © Ashleigh M. Westphal 2019. All rights reserved. No part of this work covered by the copyright heron may be reproduced or used in any form or by any means – graphics, electronic, or mechanical including photocopying, taping, or information storage and retrieval systems – without written permission of the author., secretive marsh bird, Kootenays, British Columbia, hydro, water management, wetlands
Splendor without spoil: restoring tidal channel habitat on Swishwash Island
Restoration of estuarine and tidal marsh habitats in Canada’s Fraser River estuary is imperative for the conservation and recovery of select depressed Pacific salmon populations and the many species that depend on them. In the 1930’s through to 1940’s, dredge spoils were deposited on East Swishwash Island, permanently altering the small delta island’s geomorphology and ecology. The purpose of this study was two-fold: 1.) Confirm and describe fish use of remnant tidal channel habitat on Swishwash Island, using juvenile Chinook salmon (Oncorhynchus tshawytscha) as a focal species and 2.) Quantify the historical tidal channel loss on East Swishwash Island and potential for restoration. Tidal channels and adjacent marshes were sampled for realized fish use, plant distributions, basic water parameters, and large woody debris (potential predator refugia). Remote data sets (historical and present-day) were used to quantify historic, current, and future tidal channel density scenarios. Swishwash tidal channels were utilized during the sampling period by Chinook salmon with comparable relative abundances and fork lengths. Tidal channel capacity and marsh habitat have been reduced by 50% on East Swishwash Island due to spoil deposition and marsh erosion. Based on reference conditions derived from undisturbed and historic marsh islands, restoring island elevations could facilitate the addition of 1 km of marsh edge while increasing tidal channel area on East Swishwash Island by nearly 200%. This would provide important habitat in a fragmented distributary of the Fraser River estuary to species of fish and wildlife, including 3 ecotypes of juvenile Chinook salmon., © Kyle Armstrong, 2019. All rights reserved. No part of this work covered by the copyright heron may be reproduced or used in any form or by any means – graphics, electronic, or mechanical including photocopying, taping, or information storage and retrieval systems – without written permission of the author., Estuaries, Chinook, Oncorhynchus tshawytscha, rearing, restoration, mitigation, tidal channels