This report identifies and summarizes major peatland vegetation work that has been conducted in the Boreal Plain. Data has been screened to meet the needs of the project and compiled into a Microsoft Access database. A total of 705 sites were identified and entered into the project database. Vegetation data compiled in the database were partitioned into peatland communities following the Alberta Wetland Inventory (AWI) classification system and along known pH gradients. AWI is a functional classification system that identified major wetland classes, canopy cover and landform modifiers. When coupled with known pH gradients that include poor (4.5 – 5.5), moderate-rich (5.5 – 7.0) and extreme-rich (> 7.0) systems, 18 peatland classes were identified.
Peatland communities identified included 4 bog classes, 13 fen classes and 1 swamp class. As some wooded swamps can accumulate peat they were included in the analyses. Only some of the 18 identified peatland communities have site representation in the Regional Municipality of Wood Buffalo, however all peatland classes identified are known to occur in the region. Site-species curves identified that only some of the peatland classes had adequate data available to confidently discuss community composition and included 3 bog classes and 8 fen classes.
Following data compiled in the database, bogs are dominated by a tree canopy of Picea mariana and a shrub layer of Ledum groenlandicum. Other frequently present species with high average cover values include Chamaedaphne calyculata and Kalmia polifolia in bogs with internal lawns (BTNI) and Rubus chamaemorus and Vaccinium vitis-idea in shrubby bogs (BONS) and wooded bogs (BTNN). Characteristic forbs include Smilacina trifoliata in bogs with internal lawns (BTNI) while Eriophorum vaginatum is a characteristic frequent high cover species of both BTNI and BONS. Sphagnum, including S. angustifolium S. fuscum and S. magellanicum, are frequently present in all bog types. Polytrichum strictum is present in more open, shrubby bogs (BONS) while Pleurozium schreberi is typical of drier wooded bogs (BTNN).
Unlike bogs, frequent and relatively high cover tree species present in nonpatterned wooded fens (FTNN) include Picea mariana and Larix laricina. Picea mariana dominates in poor wooded fens, while Larix laricina dominates in moderate-rich wooded fens.
Shrub species vary with Betula pumila the dominate shrub species in nonpatterned, wooded and shrubby fens and open to wooded patterned fens. Andromeda polifolia, Ledum groenlandicum and Salix pedicellaris are more restricted in the fen classes they occur in however they are also frequent in some fen classes. No shrubs are frequently present with a high average cover in nonpatterned, open fens.
Species of Carex dominate in patterned fens and nonpatterned shrubby and open fens and include:
• Carex aquatilis in moderate-rich nonpatterned shrubby and open fens
• Carex diandra in moderate-rich nonpatterned open fens
• Carex lasiocarpa in poor and moderate-rich patterned fens, nonpatterned moderate-rich shrubby fens and nonpatterned poor open fens. This species is likely also an important component of nonpatterned poor shrubby fens; however the current data indicates Carex lasiocarpa has an average cover value that is less than 5%.
Other frequent forb/species with relatively high average cover values include Menyanthes trifoliata, which occurs in patterned moderate-rich fens and nonpatterned moderate-rich shrubby fens and Smilacina trifolia that occur is nonpatterned moderate-rich wooded fens and patterned poor fens.
Frequent and common bryophytes include Sphagnum species in nonpatterned, wooded fens and nonpatterned, poor shrubby fens. Tomenthypnum nitens is a frequent and common species in all fen classes except nonpatterned, open fens. More open patterned and nonpatterned graminoid dominated moderate-rich fens both include Campylium stellatum as a frequent and common species, with Scorpidium scorpioides and Drepanocladus revolvens also present respectively.
Recommendations for sampling peatlands are provided as is follow-up resulting from this project. As many of the peatland class site-species curves had insufficient data (i.e., new common species would likely be found if additional sites were incorporated in the database) further work on linkage of vegetation and environmental data is not recommended at this time.
It is recommended that the chemical data gathered in the database generated as part of this report be evaluated relative to companion data collected for both natural and reclaimed marsh ecosystems. If peatland sites are identified to have chemical overlap with natural and/or reclaimed marsh ecosystems then the peatland class(es) associated with those sites should be identified.
In addition, it is recommended that as follow-up a program focused on vegetation and chemical data collection associated with the above identified peatland class(es) be initiated by the WASG in the RMWB. The goal of the program would be to:
• fully describe the vegetation and chemistry of targeted peatland classes
• understand the controls on frequent and common species present in targeted peatland classes
• identify environmental factors that control the presence (and absence) of common and frequent species in the peatland class(es)