Stephanie J. Connor

Wetlands in the Oil Sands Region of Alberta are vulnerable to direct and indirect effects of human development including land disturbance, hydrologic alteration, and addition of contaminants. Nineteen wetlands in the Athabasca Oil Sands Region were monitored over a five-year period to evaluate differences in water quality and benthic invertebrate composition between sites near to and further afield from surface mining operations. Concentrations of dissolved sulphate, dissolved iron, total dibenzothiophenes and specific conductance were significantly higher in wetlands near to surface mining operations. In addition, beta diversity of wetland invertebrates was higher in wetlands further afield of the industrial centre. Drivers of benthic assemblage differences among sites include specific conductance and pH. Conductance was positively correlated with Caenidae (Ephemeroptera) abundance and pH was negatively correlated with abundance of Naididae (Annelida).

Boreal wetlands within the oil sands region of Alberta, Canada, are subject to natural and anthropogenic pressures, resulting in the need for monitoring these sensitive ecosystems to ensure their protection. This study presents results from Canada’s pilot Oil Sands Monitoring (OSM) Wetland Program. This study is part of a project that seeks to assess and determine which of a selection of wetland indicators is suitable for identifying changes to wetland ecosystem “states” within a regional wetland monitoring program resulting from the effects of oil sands development. Specifically, this study seeks to identify indicators that can detect changes in a wetland ecosystem “state” using data from a 3-year pilot of the OSM Wetland Program and identify potential high-level oil sands-related pathways through which changes in states may occur, where appropriate. The monitoring data acquired during the pilot program are synthesized to identify preliminary trends and programmatic knowledge gaps, and future recommendations for an improved long-term “core” monitoring program are discussed. This study does not seek to attribute changes in wetland states measured via indicators to specific oil sands pressures but focuses on identifying those indicators that are sensitive enough to identify change over time. The results suggest that water quality, benthic invertebrates, and vegetation indicators can identify changes in wetland states over time, whereas wildlife indicators are inconclusive. Further, it is recommended that hydrometeorology data are acquired in parallel to other indicator data for contextualizing climate conditions. The findings from this work provide insights for developing and transitioning the OSM Wetland Program to a long-term effort, in addition to providing information for other regional wetland monitoring programs.

Boreal peatlands provide numerous ecosystem services ranging from carbon sequestration to the provisioning of habitat for species integral to Indigenous communities. In the Oil Sands Region of Alberta, Canada, human development related to oil and gas extraction occurs in a wetland-dominated landscape. Wetland monitoring programs can determine the extent to which development impacts wetlands, but existing monitoring programs focus on characterizing biodiversity across the region and on compliance and regulatory monitoring that assumes impacts from oil sands development do not extend past lease boundaries. This is unlikely to be true since some impacts, such as particulate deposition, can extend over large areas contingent on local weather and topography. To inform the development of a new regional wetland monitoring program to assess the cumulative effects of oil sands development on wetlands, we synthesized information on the scope of wetland research across the Oil Sands Region, including the anthropogenic stressors that impact wetlands and the wetland characteristics sensitive to different disturbances. We developed a conceptual model linking human development with wetland ecology in the region to make explicit the relationships among oil sands development stressors and different components of wetland ecosystems. By highlighting testable relationships, this conceptual model can be used as a collection of hypotheses to identify knowledge gaps and to guide future research priorities. relationships among We found that the majority of studies are short-term (77% were ≤ 5 years) and are conducted over a limited spatial extent (82% were sub-regional). Studies of reclaimed wetlands were relatively common (18% of all tests); disproportionate to the occurrence of this wetland type. Results from these studies likely cannot be extrapolated to other wetlands in the region. Nevertheless, the impacts of tailings contaminants, wetland reclamation activities, and surface water chemistry are well-represented in the literature. Research on other types of land disturbance is lacking. A coordinated, regional monitoring program is needed to gain a complete understanding of the direct and indirect impacts of human development in the region and to address remaining knowledge gaps.

Habitat degradation associated with resource development is a major ecological concern, particularly in Canada’s boreal zone where limited information on biodiversity is available. Habitat degradation can lead to reductions in biodiversity and ecosystem function, especially when drivers of variability and diversity patterns have not been identified for a region of interest. In this study, the distribution of diatom genera in the Peace–Athabasca Delta in northeastern Alberta was examined in relation to seasonal, geographic, and alkalinity gradients. Grab samples of six abiotic variables (total dissolved nitrogen, total dissolved phosphorus, dissolved iron, turbidity, pH, and specific conductance (SPC)) were taken from 12 remote wetlands over three sampling periods, and regressed against an ordination of diatom community composition to identify key environmental drivers of diatom community variation. Indirect gradient analysis identified two major gradients among sites. First, separation of sites among sampling periods showed successional seasonal changes in diatom community composition. Second, separation of sites from the Peace sub-delta and Birch sub-delta showed a gradient of geographic separation. Direct gradient analysis failed to explain the underlying drivers of these two gradients, but did show that alkalinity is a key driver of diatom community composition in the Embarras sub-delta, and that these sites could be particularly vulnerable to community changes associated with acidification.