Developing restoration protocols for disturbed peatlands in the Hudson Bay Lowland

De Beers Canada's Victor Diamond Mine is located in the world's third largest wetland. As a result of this mining activity, the Hudson Bay Lowland will experience about 5000 hectares of peatland disturbance due to mining and construction activities. De Beers Canada is required by law to restore the disturbed area to its previous natural state. Peatland restoration methods have been established in southern parts of Canada. Nevertheless; differences in hydrological conditions, climate and the method of disturbance at Victor mine differs from those in southern parts of Canada. Furthermore, with the risk of introducing foreign species to the Hudson Bay Lowland, the company is required to explore weed-free mulch or local cover options. Four experiments were set up to test the effects of mulch, fertilizer, timing of Sphagnum fragment introduction and the need to manually introduce species from donor sites. Three disturbed sites were chosen; 1) an abandoned Argo trail, 2) a buried pipeline and 3) an abandoned winter road. The first experiment was set-up to determine the surface treatment for establishing Sphagnum fragments onto bare peat. Two experimental sites were chosen, an abandoned Argo trail and the buried pipeline. Two Sphagnum species (S. fuscum and S. fallax) of fragments were tested using two weed-free commercial mulches, four local covers ( Carex aquatilis cuttings, two densities of Eriophorum vaginatum companion plants and peat blocks used as a topographical amendment), and no cover treatments. Weed-free mulches or local options are important to avoid introducing any foreign species to the area. The second experiment determined the interaction between a weed-free straw mulch and rock phosphate fertilizer. Full factorial combinations of weed-free straw mulch and rock phosphate fertilizer was tested using the same two species of Sphagnum as the first experiment. This experiment was set-up at the buried pipeline site to determine the need for either mulch, fertilizer or both. Thirdly, S. fallax and S. fuscum fragments were exposed to winter conditions at three different times of the year (November, January and March) and either received a mulch or not. It is important to introduce fragments at these times of the year because the frost has already hardened the ground and machinery can travel onto the peatland. In June 2008, the fragments were sown onto bare peat at the buried pipeline site and capitula counts were measured at the end of the growing season (August 2008). The final and fourth experiment tested the effects of straw mulch (present or not) and three dose levels (none, low and high) of phosphate fertilizer on peatland species growing on top-cut hummocks on an abandoned winter road. No Sphagnum fragments or other peatland species were introduced onto the top-cut hummocks. The term of the experiment was from late May 2008 until August 2008. This experiment showed preliminary results for further testing to restore peatland species onto the damaged hummocks.;These four experiments will help in the development of protocols to re-establish Sphagnum species on disturbed peatlands in the Hudson Bay Lowland after mining.;Results of the four experiments indicated that the manual introduction of Sphagnum species onto bare peat and on winter road top-cut hummocks sites is a critical step in establishing a cover. Time of year the fragments were introduced had no significant effect on the growth of Sphagnum fragments, except at the peak of the summer when establishment remained poor. Straw mulch does not appear to be essential to establish Sphagnum fragments in the Hudson Bay Lowland.