Plant species suitability for reclamation of oil sands consolidated tailings

• Main Author: Naeth, Anne
• Language: English
• Published: 2009
• Online Access: http://hdl.handle.net/2429/9425

Oil sand companies are evaluating techniques to solidify wet slurries and produce a non-segregating tailings stream known as consolidated or composite tailings (CT). Successful establishment of vegetation directly on CT can contribute to dewatering and assist in meeting reclamation objectives. The goal of this research was to develop a list of plant species which may be suitable for dewatering and reclamation of consolidated tailings. A growth chamber study was conducted in 1999 and a greenhouse study in 2001. In total, 44 native grasses, 50 native forbs, 8 introduced grasses and 4 introduced forbs were tested. The density of seedlings was recorded for 6 to 10 weeks depending on the experiment. Maximum emergence and establishment were calculated, and species vigour evaluated. Height and leaf number were measured in 1999. Grasses had higher average emergence and establishment (19.6% and 29.8%) than forbs (16.1% and 7.9%) in both studies. Introduced species had higher emergence and establishment (56.4% for grasses and 37.4% for forbs) compared to native species in CT treatments. All species except introduced grasses had higher emergence in control treatments compared to CT treatments. Field research needs to be conducted to further test the 14 grasses and 6 forbs identified in these studies as having potential for biological dewatering and reclamation of consolidated tailings.