The main objective of this project was to identify and summarize data from marsh vegetation communities and corresponding environmental conditions in natural areas and in the oil sands region of Alberta from existing literature and databases. Wetland data included in this project were geographically restricted to the Boreal Plain of Alberta, Saskatchewan and Manitoba. We believe that marsh establishment and creation holds the most immediate potential to reclaim wetland ecosystems after mining. However, given the proper hydrology, topography and time we hope these wetlands will have the capacity to continue their successional pathway towards other wetland types such as fens, which originally occurred on the landscape prior to mining.
We examined studies primarily from the Boreal Plain of Alberta and include datasets ranging from northern Alberta, western Manitoba, Elk Island National Park (central Alberta) and northwestern Alberta in the database (Figure 2). There are a total of 488 taxa identified to vascular and non-vascular species level documented in this geographical range however there could be more species that were not encountered or identified. There were an additional 52 taxa identified to genus or group level for a total of 540 species (488 species plus 52 genus-level taxa). Of the 540 species from all the studies examined, 24% (129/540) of species were documented only once. It is unlikely that these are rare and may be due to the wide range of differences in field sampling design and plant identification skills.
The top 10 dominant (most frequent) species are Carex atherodes, Typha latifolia, Carex spp., Calamagrostis canadensis, Carex aquatilis, Scolochloa festucacea, Lemna minor, Galium trifidum, Salix spp., and Polygonum amphibium across the entire region (includes wetlands in both natural areas and oil sands areas). Wetlands in natural areas and oil sands areas differ in their dominant species (most frequent) composition. Sedge communities dominate wetlands in natural areas while wetlands in oil sands areas are dominated by saline tolerant, pioneer and invasive species. Wetlands in natural areas are more species rich than wetlands in oil sands areas (472 species vs. 289 species respectively). Preliminary data analyses identified seven vegetation community groups in the region: Group 1) mudflat/disturbed marshes (Bidens-Rumex), Group 2) submersed and seepage wetlands (Caltha palustris-Lemna trisulca), Group 3) emergent marsh (Carex diandra-C.lasiocarpa-C.aquatilis), Group 4) emergent marsh to wet meadows (Typha latifolia-Mentha arvense), Group 5) semi aquatic fringe (Utricularia), Group 6) disturbed saline (Puccinellia-Hordeum jubatum) and Group 7) upland fringe and saline wet meadows (Triglochin maritima-Scirpus validus). Based on hierarchical cluster analysis and non-metric dimensional scaling ordination analysis, vegetation communities appear to be structured along water depth/moisture and salinity gradients.
Many of the relevant marsh studies did not have environmental data associated with vegetation data. The studies that did have environmental data were not directly collected at the same location as the vegetation. A clear knowledge gap in the available data exists in linking vegetation communities to environmental/water chemistry conditions in both oil sands and natural areas and further investigations are required to improve our understanding of environmental ranges and tolerances of species in northern marsh communities.