Carbon and nitrogen fluxes in reconstructed oil sands soils

点击翻译按钮获取中文摘要

The Athabasca Oil sands located near Fort McMurray, in northeastern Alberta, contain an estimated 1.3 trillion barrels of bitumen. Approximately 10% of this deposit is shallow enough to be surface mined. Following surface mining, reclamation involves soil reconstruction using organic and mineral materials salvaged prior to disturbance. Devising strategies to maximize nutrient resources in the reconstructed soils is key to successful reclamation. In particular, the re-establishement of biogeochemical cycling between plants and reconstructed soils is a central component of site productivity through its regulation on overall nutrient patterns. This research will characterize soil carbon and nitrogen fluxes at sites representative of reclamation practices in the Oil sands area. These will be compared to sites recovering following fire, the main natural disturbance for Alberta's boreal forests. Linking carbon and nitrogen fluxes to soil microbial communities in defined laboratory conditions will provide a baseline for understanding nutrient availability in these soils. Field experiments will examine the in situ ability of different litter materials to supply nutrients for soil microorganisms, soil fauna, and plant uptake. Finally, results will be integrated so that a mechanistic model of carbon and nitrogen fluxes can be developed for these reconstructed soils. Comprehensively, the research proposed here will provide quantitative relationships between measurable carbon and nitrogen fluxes and fundamental soil processes that will help develop better guidelines for the sustainable reclamation of the Oil sands region.