Hydrology of passive and active restoration in abandoned vacuum extracted peatlands, Southeast Manitoba, The

Natural, self-regulating bogs have high water tables during wet periods of the year and can retain their moisture content within the acrotelm to sustain the physiological functions of the Sphagnum during dry periods. Peat extraction disrupts the hydrology and natural regeneration of most cut-over bogs. Although regeneration occurs more readily on block-cut sites, vacuum harvesting has become the main method of extraction and therefore requires more rigorous restoration efforts afterwards. Two methods of restoration are observed in this paper, passive restoration at Moss Spur and active restoration at Elma North. To establish and regenerate, Sphagnum moss requires a water table within 0.4 m of the peat surface and soil-water pressure (ψ) not exceeding -100 cm. These parameters were established for bog restoration; however, bogs develop from fens, thus the active restoration is aimed towards a fen system. The hydrogeomorphic setting in Manitoba allowed for Moss Spur to regenerate passively, while Elma presented an opportunity to explore a combination of active restoration techniques used in eastern Canada and Europe. Moss Spur was expected to be barren, much like a comparable site in Quebec, however groundwater discharge was found to occur throughout Moss Spur over three study seasons which likely resulted in its spontaneous regeneration since abandonment. It is still unknown if the active restoration treatments conducted at Elma will shorten fen regeneration time to decades rather than centuries, but in one season the water table levels were increased >100 cm and soil tension improved to bring it well within the acceptable threshold for Sphagnum establishment.