Background
Fig 4. Source: The Future of Canada's Oil Sands | Earth.Org
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Alberta's oil sands deposits cover an area of over 140,000 km2 (Alberta Energy 2015) in the Athabasca, Cold Lake, and Peace River areas. An area close to 5,000 km2 is suitable for open-pit mining (Alberta Chamber of Resources 2015).
When the oil sands ore is mined out of the ground, they will be first crushed in the crusher before sending them to the extraction plant. In the extraction plant, oil sands will be mixed with hot water to separate the bitumen from oil sands. After that, the bitumen will be sent to refineries to produce fuels. Then, the remain material are tailings, which are made of sand, clay, water, and the residue of bitumen. |
Enhanced Non-Segregated Tailings (ENST)To improve the effectiveness of the tailings solidification process and to make the tailings less harmful to vegetation, CNRL has developed a tailings management plan to combine tailings sand with thickened fines. As the result of this plan, Non-Segregating Tailings (NST) were initially produced and selected for further testing of their effects on vegetation. In 2017, CNRL started testing a new enhanced NST technology (ENST), which captures over 80% of fines. This new technology combines chemical treatment of tailings with a flocculant that causes the solids to clump together, and then mechanically pressing it between large metal plates lined with filter materials. The resulting clay fines cake is dense and strong enough to be shipped directly into a reclamation area.
The potentially harmful factors for revegetation that have been associated with oil sands tailings include high pH, poor aeration, and high concentrations of NaCl, Na2SO4, naphthenic acids, boron, fluoride, and heavy metals. |
MycorrhizaMycorrhizal can exist in many forms. During the infection process, the fungus invades the root epidermis and cortex, but does not enter the vascular cylinder or the meristem that is covered by the root cap. Mycorrhizae are classified according to the relation ship of the fungus to the root cells. The two main types are ectomycorrhizas in which fungal hyphae penetrate the spaces between cells, and endomycorrhizas where projections of the fungus enter the interior of the cell.
The special relationships formed between certain fungi and plants, called mycorrhizae, which have been shown to dramatically enhance the establishment, growth, development, and survival of plants. Mycorrhizal associations have been shown to benefit plants by increasing: 1) nutrient and water absorption; 2) root health and longevity; 3) tolerance to drought, high soil temperatures, toxic heavy metals, extremes in pH and trans plant shock. In addition, the fungal symbiont in this relationship can transport metabolites from one plant to another, produce plant growth regulators and antibiotics and may protect roots from invasion by pathogens. |
Research Objective
There are two objectives in my research project:
1. Examining the potential effects and toxicity of oil sands tailing to reclamation plant. 2. Investigating the role of mycorrhizae in promoting plant growth and development. The ultimate purpose of this experiment is to explore the growth-promoting and stress-resisting effects of P.indica on B.napus under tailings stress conditions by establishing the symbiosis system between P.indica and B.napus. Better growth-promoting and stress-resisting can improve the reclamation success rate and efficiency, provide better reclamation strategies for tailings reclamation. |