Improving revegetation of oil sands reclamation sites with mycorrhizal ericaceous plants

点击翻译按钮获取中文摘要

Ericaceous plants have been difficult to establish in oil sands reclamation areas due to their dependence on ericoid mycorrhizal associations for survival in harsh environments. Ericaceous plants play important ecological roles in the boreal forests. Therefore, their successful re-establishment in oil sands areas is among the reclamation priorities for the oil sands industry. In an earlier study, we demonstrated that a common reclamation practice involving soil stockpiling is detrimental to ericaceous plants. Even a relatively short, one-year, duration of stockpiling resulted in a drastic decrease in the abundance and diversity of root ericoid mycorrhizal (ERM) fungi affecting plant growth and survival. We also showed that the re-establishment of ericaceous plants in oil sands reclaimed areas is not likely to be successful without the presence of appropriate types of ERM fungi. It has been previously established that high soil pH and frequent episodes of drought are common detrimental factors affecting plant growth in reclamation sites. The proposed project addresses these concerns by carrying out controlled-environment and field studies to investigate different approaches that could be used to improve survival and growth of ericaceous plants in oil sands reclamation areas. The project also aims at better understanding of the plant-mycorrhizal interactions that improve high soil pH tolerance and plant water relations in ERM plants. The principal long-term objective of the proposed study is to contribute new knowledge that can be used to improve the reveteation of oil sands areas with ERM mycorrhizal plants. Specific objectives are to: 1) Develop the methods that could be used to enhance revegetation potential of stockpiled reclamation soil by inoculating roots with different ERM cultures, 2) Examine the effects of stockpiling duration on ERM inoculation potential and growth of plants, 3) Determine pH tolerance of various ERM associations, and 4) Examine the processes contributing to enhanced drought resistance in blueberry plants colonized with the ERM fungi Pezoloma ericae and Meliniomyces variabilis.