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
This study began to investigate potential facilitative effects among shrub species in riparian ecosystems in southwestern British Columbia. I ran two concurrent studies. Six plots for each of four treatments were established at the Coquitlam River Wildlife Management Area. The first two treatments compared the survival, growth, flowering, and herbivory rates of planted twinberry seedlings in plots where the shrub layer was removed to plots where it was not. The other two treatments compared the survival, growth, leaf loss, flowering and herbivory rates of snowberry plants in plots where the salmonberry upper shrub layer was removed to those where it was not. No significant differences between the measured parameters in any of the treatments were found. These results are discussed in the context of the riparian forest ecosystem and current facilitation theory. The results are then used to inform an ecological restoration plan for the Suwa’lkh School Forest., Facilitation, Riparian forests, Native vegetation, Symphoricarpos albus, Lonicera involucrate, Rubus spectabilis, Ecological restoration
Forestry in British Columbia’s old-growth forests has reduced critical foraging and breeding habitat for the coastal northern goshawk (Accipiter gentilis laingi) and restricted population growth. Now at-risk, efforts to recover this subspecies have focused on establishing suitable habitat and a well-distributed population within the province. However, regional diets and associated dynamics are also critical to goshawk recovery and remain poorly understood. Including a synchronous predator-prey recovery approach to current plans can bridge these knowledge gaps. A new model and methods were developed to translate prey biological requirements into structural surrogate features that could be parameterized and ranked within GIS software. Applying these ranks to known goshawk territories in the South Coast allowed for the visualization and quantification of areas with subpar predicted prey abundances. This provided insight on links between prey and forest structure and can be used to direct future restoration and research decisions for coastal goshawk prey-based recovery.
Over the past half century, urbanization has caused drastic changes to the hydrology and geomorphology of streams and rivers. The Serpentine River is a low-elevation, rain-dominant river located in the City of Surrey, British Columbia. Over the years, urbanization of the watershed, particularly in the upper reaches, has degraded what once was high quality spawning habitat for five salmonid species. The current project is an evaluation of previous restoration efforts at seven study sites and a restoration plan to effectively increase spawning habitat in the Upper Serpentine River. Grain size analysis of the study sites found up to 57% fine sediment in the subsurface particles, attributing to siltation rates of 1.2-1.6 kg/m2/day. Erodible grain sizes at the study sites ranged from 29-164 mm, which mostly exceeded the median size of spawning gravel. These results were verified with a tracer rock study, which together concluded that instream structures were required to reduce tractive forces and increase gravel retention.
Newbury weirs, or constructed riffles, were proposed as treatments because their hydraulic characteristics increase flow resistance, promote gravel retention, and create intergravel flows. Newbury weirs involve large diameter rocks spanning across the entire stream, causing accumulation of gravel on the upstream side and pool formation downstream side. Substrate scoured at the pool will be deposited at the tail end of the pool, creating spawning habitat in accelerating and downwelling waters. Bank stabilization using dense live staking with a protective rock toe key was prescribed to reduce further channel incision and siltation. In the longterm, watershed-level priorities including passage through the Serpentine sea dam, monitoring for urban contaminants, and installation of green infrastructure was recommended.
The proposed treatments are relatively inexpensive, and if successful, will reduce repeat addition of spawning gravel and increase salmonid production in the Serpentine River. However, the value of the current project extends beyond fish productivity estimates. Monitoring data from restoration works can be used to inform future urban stream restoration projects and contribute to the continual improvement of restoration techniques. The effects of restoration on not only sediment form (ie. gravel depth and size) but also processes (ie. sediment scour and fill) should be investigated in the field to verify theoretical models.
Restoration of salmonid habitat has been completed in many urban areas; however, the success of these projects may be limited without consideration of water quality. Urban watersheds are affected by stormwater runoff which transfers toxic substances such as heavy metals, hydrocarbons, and fine particles from impervious surfaces into streams. Previous research has documented impacts of stormwater causing premature death in spawning coho (Oncorhynchus kisutch), and related extent of impervious surfaces to impacts on benthic invertebrates. This research aims to expand our knowledge on the effects of stormwater runoff on water quality and benthic invertebrate communities, and
make recommendations for restoration of Mosquito Creek, in North Vancouver, British Columbia. Stream water quality was monitored, site habitats were assessed, and impervious surfaces were mapped. Benthic invertebrate samples were collected and analyzed for abundance, diversity, and pollution tolerance, comparing upstream and downstream of a stormwater inflow and two sites on a reference stream. Average water quality measurements showed minor impacts related to elevated temperatures. However, benthic invertebrate metrics revealed chronic water quality issues, reflecting cumulative impacts. Pollution tolerance index and abundance were reduced at the downstream Mosquito Creek site suggesting impacts from the stormwater inflow, while the Ephemoptera, Plecoptera, Trichoptera (EPT) to total ratio and overall stream health
(Streamkeepers Site Assessment Rating) were significantly lower at Mosquito Creek overall suggesting watershed impacts from impervious surfaces and point-source pollution events. Restoration recommendations including a rain garden are discussed to improve water quality for salmonids., Restoration, Urban streams, Salmonids, Benthic invertebrates, Water quality, Stormwater
Forestry practices are thought to be the major cause of degraded salmonid habitat and declining steelhead populations in the Oktwanch River on Vancouver Island. Large woody debris installations and channel modifications were completed in Reach 1 of the Oktwanch River and adjacent side channels in 2001 to provide spawning and rearing habitat for multiple salmonid species and prevent further degradation, but were ultimately unsuccessful. This study investigated if watershed-scale restoration, rather than reach-scale, is necessary to restore this habitat for steelhead in the Oktwanch River indefinitely. This was achieved through an assessment of fish habitat in Reach 1 of the Oktwanch River and adjacent side channels and spatial analysis of the Oktwanch watershed using Landsat historical aerial imagery and i-Tree Canopy. The findings from this study suggest watershed-scale changes to forestry practices are required to restore steelhead populations in the Oktwanch River., forestry practices, watershed-scale restoration, reach-scale, woody debris installations, channel modifications
In agricultural landscapes, hedgerows provide critical habitat for songbirds. Himalayan Blackberry (Rubus armeniacus; HBB) is a widespread invasive species in the Pacific Northwest that has been linked to lower breeding songbird diversity. My study explored two possible explanatory mechanisms: educed structural complexity and lower arthropod abundance as a food source. I conducted avian point counts in 51 hedgerow segments at two locations in the Lower Mainland of British Columbia. In these segments, I quantified vegetation structure using a Foliage Height Diversity (FHD) metric derived from LiDAR data. I sampled arthropod abundance on the foliage of woody understory vegetation. I used multiple regression to identify best fit generalized linear models. Songbird diversity decreased with HBB % cover and increased with FHD. However, arthropod abundance was unrelated to bird metrics, and similar between HBB and other native shrubs. This suggests that hedgerows should be managed to control HBB and maximize vegetation structure., songbird diversity, agricultural landscapes, Himalayan Blackberry, hedgerows, arthropods, LiDAR