Results of the Tundra Mine, NT Revegetation Trial Using Locally Harvested Pioneer Species Instead of Grass Seed and FertilizerThursday, November 22, 2018 - 09:00 to 09:19 Theatre 3
The abandoned Tundra Gold Mine, 240 km northeast of Yellowknife, NT, is located in the transition zone between the boreal forest and the tundra. The shorter growing season, extreme cold, low precipitation, shallow depth of nutrient poor rocky soils, desiccating winds and the presence of permafrost make revegetation efforts challenging. The 2015 trial focused on establishing locally harvested pioneer species to facilitate natural recovery and succession as an alternative to using native and non-grass seed and fertilizer. The soils were mechanically loosened creating a 30 m by 70 m plot of offset holes on the side of the former tailings pond leaving six control plots (4 m by 4 m) within the trial to compare growth on loosened soils to compacted soils. No soil amendments were added. After one year 81% of the 93 1.2 m long live dormant willow (Salix athabascensis) cuttings produced shoots. 90 transplant plugs each of Juncus stygius, Juncus drummondii, Equisetum arvense and Carex aquatilis were planted in 30 groups, half in the control plots and half in the adjacent rough and loose, with an 83% and 86% survival rate, respectively. Significant plant growth was observed in the second year over the first year when plants were diverting resources to root growth at the expense of shoot growth.