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.
Since the 1860s the watershed of Spanish Bank Creek has experienced many ecological disturbances due to extensive old-growth logging and urban development. Most notably, these disturbances have altered the vegetative composition and hydrology throughout the watershed. The historic old-growth forest has been replaced by species typical of earlier seral stages, as well as invasive species such as English ivy (Hedera helix). This disturbed vegetation mosaic is characterized by an arrested ecological trajectory that perpetuates degraded conditions. Urban development has eliminated over a third of the historic length of Spanish Bank Creek and storm drains were installed to direct residential drainage into the stream. The combination of a disturbed forest and degraded hydrology intensifies runoff and associated sediment transport, and decreases the hydraulic retention time of the watershed. This has led to a significant decline in abundance of chum, coho, and cutthroat salmonids in Spanish Bank Creek.
Previous research has established how trees partition precipitation into throughfall, stemflow, and interception, however there are few studies examining the effects of canopy closure on throughfall within the context of ecological restoration. Thus, the objective of this paper is to determine if increasing canopy closure can be used as a restoration model to decrease throughfall, and consequently increase the hydraulic retention time of the watershed. Results indicated that greater canopy closure was associated with decreased precipitation throughfall.
From these results I formulated a restoration goal and several treatments that would increase canopy closure, and also ameliorate the degraded vegetative composition and hydrology of the watershed. The restoration treatments prescribed in this paper constitute five years of physical enhancements from which self-sustaining biological processes will continue to restore ecosystem function and structure. Successful implementation of these restoration treatments will positively affect regional biota, as well as users of the Pacific Spirit Regional Park who come to recreate, learn, and connect.
Geochemical and biological attributes of three intertidal areas in the Squamish Estuary with different levels of disturbance (low, medium, and high) were assessed to determine short-term ecosystem responses to localized restoration efforts conducted one year previously on a former log handing site. Sediment and macroinvertebrate variables were analyzed among sites to characterize the ecosystems response and provide insight on the nature and process of an assisted successional trajectory. Invertebrate composition and biomass were lowest on the site with the highest level of disturbance. The high disturbance site also contained the highest percentage of fine sand (0.0067 mm to 0.25 mm). This confirms that in the short term there are distinct site responses to disturbance and ameliorative restoration efforts – even in a highly dynamic estuarine environment. The medium site contained more invertebrates than the low disturbance site indicating that something other than localized disturbance is affecting the invertebrate community on the low site. All sites exhibited a less-rich and less diverse invertebrate community than that of historical records (circa. 1970-1980). Invertebrate community in the east delta today is more typical of estuarine environments with higher salinity levels - which indicates more widespread levels of disturbance throughout the Estuary is affecting the study sites. This
study highlights the importance of considering temporal and spatial scales when setting restoration goals, objectives and creating monitoring plans. Additional monitoring of sediment, invertebrate, and other variables on restored and reference sites is recommended to characterize typical recolonization and reassembly attributes of restoring intertidal estuaries in coastal British Columbia. This would provide evidence and rigor in determining effective restoration techniques and management strategies for a critical and increasingly threatened ecosystem., Macroinvertebrates, Restoration, Sediment, Benthic ecology, Estuaries, Intertidal flats
The Nicomekl River flows through historic Katzie First Nation territory in Surrey, British Columbia. The river provides salmon the linkage between their upland spawning and rearing grounds and the Pacific Ocean where they mature. Anthropogenic development has reduced habitat connectivity along the river, denuded the banks of vegetation, removed instream complexity, constrained the channel, regulated flow, and altered the water chemistry. A tidally controlled 7-gate sea dam is the source of the critical connectivity bottleneck on the river. It impairs free longitudinal migrations of adult and juvenile salmonids and increases adult and juvenile predation. Through literature review and site assessment, this study suggests a suite of restoration treatments to restore connectivity and site-based habitat attributes to the Nicomekl River. The study then considers management options in light of climate change, sea level rise, and how to generate public involvement to support the proposed treatments. The study concludes that urban stream restoration faces challenges as it must find a balance between the environmental and social needs of the Nicomekl River beyond simply repairing ecosystem damage and degradation., riparian restoration, salmonids, migration bottlenecks: connectivity
Urbanization of areas alters the natural hydrology of the land through the creation of impervious surfaces, removal of vegetation, and construction of storm sewer systems. These alterations impact physical processes and the biological communities of our waterways through the introduction of pollutants, creation of uncharacteristic hydrological regimes, and habitat loss and fragmentation. Integration of natural areas in our built environments will mitigate some of these effects and reduce the degradation of streams in urbanized watersheds.
Guichon Creek flows through an urbanized environment, which includes the British Columbia Institute of Technology (BCIT) Burnaby campus. A tributary flows into Guichon Creek at the south end of campus and the majority of its flow is from a stormwater sewer which receives runoff from the residential area east of campus. The tributary is approximately 150 metres and runs between a community garden and a small gravel parking lot before entering Guichon Creek.
This project proposes restoration of a 2,000 m2 parcel of land between Guichon Creek and the tributary. Restoration activities involve removal of an existing parking lot, management of invasive hybrid Japanese knotweed (Fallopia x bohemica) and Himalayan blackberry (Rubus armeniacus), creation of an off channel wetland, and addition of natural in-stream structures to the tributary. Wetlands provide important hydrological and ecological functions that will contribute to the restoration efforts on Guichon Creek. This wetland will improve hydrological functions of the Guichon Creek floodplain through increased groundwater infiltration, creation of a storage area, and pollutant filtration. Improving these functions is also an important component of making stream ecosystems more resilient to climate change. The wetland will also provide ecological benefits such as improved water quality and creation of amphibian habitat. This project focuses on the creation of habitat for northern red-legged frog (Rana aurora) and the Pacific chorus frog (Psuedacris regilla).
Another important component of restoration in an urban environment is creating a connection between people and the environment. Restoration of this space provides opportunities for public involvement and environmental education and awareness. This creates a forum to discuss the effects of urbanization on streams and show people where the runoff from their neighbourhood ends up. Forming that connection between people and their environment is an important step to creating interest and involvement in environmental issues.