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Bitumen extraction in the Athabasca oil sands causes significant disturbance of landscapes originally rich in wetland and forest ecosystems, which now require reclamation as mandated by the Alberta Government. However, most research to date has focused on upland-forest ecosystems with little attention on wetland-peatland ecosystems, which are considered more challenging to construct due to salinization potential from ubiquitous salts used in the oil sands extraction and treatment processes; with particular focus on elevated Na+ due to its detrimental ecological effects. Syncrude Canada Ltd. (SCL) has constructed an upland-wetland system, the Sandhill Fen Watershed (SFW), to advance the understanding of wetland reclamation in the oil-sands region. The SFW is a highly engineered and managed system. Water is supplied from an artificial fresh water source and drainage is enhanced through a constructed surface outlet and an under-drain system intended to provide a downward hydraulic gradient to inhibit the upward movement of salts from the underlying waste material. The objective of this research is to understand the hydrochemical response of the SFW to variations in hydrological management with respect to sources, flow pathways and major chemical transformations of water as it moves throughout SFW. Through surface and pore water sampling, the electrical conductivity and major ions were measured throughout the growing season of 2013 and 2014. Results indicate that the combination of freshwater inflow, flushing of the system with the outflow pump and open underdrains in 2013 kept the overall salinity within the SFW relatively low, with most lowland sites under 1000 µS/cm. Major ion results indicate that most water throughout the SFW classified as Ca-HCO3 or Ca-SO4 in 2013, with higher concentrations in the uplands however Na+ concentrations did not exceed 250 mg/L at any sampling sites. With minimal management in 2014 and consequent limited freshwater input and flushing of the system, the overall salinity of the SFW increased considerably and EC at most sites in lowlands exceeded 1000 µS/cm. Na+, Ca+2, SO4-2 and HCO3- concentrations increased across the SFW, with higher concentrations in the uplands than the lowlands. Although most sites classified as Ca-SO4, the most notable change in 2014 was the presence of several Na+ “hotspots” along the southern hummocks in the SFW, where water samples classified as Na-SO4 and Na+ concentrations reached as high as 886 mg/L. Results provides evidence of modelled upward movement of Na+ from underlying waste materials and subsequent seepage from hummocks with limited pump management in the SFW. / Thesis / Master of Science (MSc)

Thesis (M. Ph.)--Chinese University of Hongkong. / Bibliography: leaves 70-74.

The effects of the fenretinide and genistein as single or combined drugs on ovarian cancer proliferation and viability were investigated. Hypothesis: Co-treatment with genistein will enable a lower dose of fenretinide to be effective in inhibiting the proliferation and survival of ovarian cancer cells. Methods: Low and high doses of genistein and fenretinide were tested on A2780s and A2780cp cells using trypan blue viable cell count, MTS assay. Results and conclusions: Unlike low doses of fenretinide, genistein had anti-proliferative effects on both cell lines. There were no additive or synergistic effects of the two compounds. Higher dose treatments induced anti-proliferative effects and apoptotic cell death in both A2780s and A2780cp cells, with a greater sensitivity of A2780s cells to both test compounds. Overall Conclusion: Genistein and higher doses of fenretinide similarly impair cell cycle progression and induce apoptosis. The anti-proliferative effects of genistein can be affected by co-treatment with fenretinide

The effects of the fenretinide and genistein as single or combined drugs on ovarian cancer proliferation and viability were investigated. Hypothesis: Co-treatment with genistein will enable a lower dose of fenretinide to be effective in inhibiting the proliferation and survival of ovarian cancer cells. Methods: Low and high doses of genistein and fenretinide were tested on A2780s and A2780cp cells using trypan blue viable cell count, MTS assay. Results and conclusions: Unlike low doses of fenretinide, genistein had anti-proliferative effects on both cell lines. There were no additive or synergistic effects of the two compounds. Higher dose treatments induced anti-proliferative effects and apoptotic cell death in both A2780s and A2780cp cells, with a greater sensitivity of A2780s cells to both test compounds. Overall Conclusion: Genistein and higher doses of fenretinide similarly impair cell cycle progression and induce apoptosis. The anti-proliferative effects of genistein can be affected by co-treatment with fenretinide

The effects of the fenretinide and genistein as single or combined drugs on ovarian cancer proliferation and viability were investigated. Hypothesis: Co-treatment with genistein will enable a lower dose of fenretinide to be effective in inhibiting the proliferation and survival of ovarian cancer cells. Methods: Low and high doses of genistein and fenretinide were tested on A2780s and A2780cp cells using trypan blue viable cell count, MTS assay. Results and conclusions: Unlike low doses of fenretinide, genistein had anti-proliferative effects on both cell lines. There were no additive or synergistic effects of the two compounds. Higher dose treatments induced anti-proliferative effects and apoptotic cell death in both A2780s and A2780cp cells, with a greater sensitivity of A2780s cells to both test compounds. Overall Conclusion: Genistein and higher doses of fenretinide similarly impair cell cycle progression and induce apoptosis. The anti-proliferative effects of genistein can be affected by co-treatment with fenretinide

In the boreal forest of Alberta, oil exploration has brought roads into previously undisturbed areas. Peatlands cover vast areas of the boreal forest, transmit water across the landscape, provide habitat for wildlife, and store carbon sequestered from the atmosphere. Roads crossing peatlands is inevitable, and little is known about how roads impact plant communities, water chemistry, and water tables. Few studies of large fen complexes have been conducted in the continental boreal forest, nor have many investigated the impact of roads. Understanding the relationships between species, water chemistry, and microtopography provides insight into the nature of continental fens and how they respond to disturbance. I examined plant communities and water chemistry characteristics of an undisturbed fen and compared the data to nearby peatlands that were disturbed by mineral haul roads. This study determined the control study site was an acidic fen with a pH generally less than 4.0 and four community types were recognized. Most of the complex was very wet, open, oligotrophic poor fen, with a treed, oligotrophic, species poor area extending between two water tracks. As the fen narrowed following its drainage, site type changed to mesotrophic poor fen, with mesotrophic rich fen communities in some marginal areas. The water table was very stable. The road sites showed signs of enriched water chemistry and changed plant communities within 50 meters of the road upstream. Downstream plant communities were less effected. Water tables appear to be influenced both upstream and downstream differently.

The effects of the fenretinide and genistein as single or combined drugs on ovarian cancer proliferation and viability were investigated. Hypothesis: Co-treatment with genistein will enable a lower dose of fenretinide to be effective in inhibiting the proliferation and survival of ovarian cancer cells. Methods: Low and high doses of genistein and fenretinide were tested on A2780s and A2780cp cells using trypan blue viable cell count, MTS assay. Results and conclusions: Unlike low doses of fenretinide, genistein had anti-proliferative effects on both cell lines. There were no additive or synergistic effects of the two compounds. Higher dose treatments induced anti-proliferative effects and apoptotic cell death in both A2780s and A2780cp cells, with a greater sensitivity of A2780s cells to both test compounds. Overall Conclusion: Genistein and higher doses of fenretinide similarly impair cell cycle progression and induce apoptosis. The anti-proliferative effects of genistein can be affected by co-treatment with fenretinide

Wetland reclamation efforts in the Athabasca Oil Sands Region seek to restore important ecosystem services that were lost consequent of disturbance from oil sands mining development in northern Alberta, Canada. Constructed on the Syncrude Canada Ltd. mineral surface lease, the Sandhill Watershed is the first attempt to engineer a landscape capable of supporting a self-sustaining wetland above a backfilled open-pit mine. In the chapters below, through characterization of porewater chemistry patterns, plant community structure, physical characteristics of soil and nutrient availability the overall performance of the wetland area (the Sandhill Wetland) is evaluated. Further, observations at the reclaimed site are compared to 12 reference wetlands (10 fens and 2 marshes) to evaluate the type of wetland to which the Sandhill Wetland is most analogous. After six growing seasons, although water table position management has occurred annually, the Sandhill Wetland exhibits many attributes similar to those of the natural sites monitored. In terms of porewater chemistry, the dominant anions and cations present in near-surface water (bicarbonate, sulfate, chloride, sodium, calcium, and magnesium) have increased annually since the first growing season. If trends continue, the chemical conditions at the reclamation site could be analogous to saline fens in about 7-8 years based on projections for increasing sodium and chloride concentrations. The Sandhill Wetland currently exhibits porewater chemistry attributes most similar to saline fens and slightly brackish marshes. Total plant cover across the reclaimed wetland was quite high averaging 95% in the sixth growing season. Using multivariate approaches (NMDS), results show that plant community structure across high and intermediate water table position areas are most comparable to marshes, with Typha latifolia and Carex aquatilis exhibiting the highest cover. Across the periphery of the site, where water table position is several centimeters below the soil surface, plant communities are quite dissimilar from the reference sites and dominated by the grass Calamagrostis canadensis. While sodium-tolerant species are present at the site, albeit at low abundance, it is unclear whether long-term exposure to sodium-dominated porewaters currently present at the Sandhill Wetland will affect performance of wetland plants that established under low-sodium conditions. In terms of soil characteristics, clear differences were apparent, namely, for soil bulk density patterns. Bulk density observations across all areas at the Sandhill Wetland were higher than the reference sites and total soil carbon concentrations were also low. These observations were expected, and as the Sandhill Wetland matures, I predict annual production and (or) deposition of plant litter/ roots and increased biological activity will restore near-surface soil properties in the wetland area, thereby increasing TC concentrations and reducing soil compaction. For functional processes, using plant root simulator (PRS) probe ion exchange membranes, results demonstrate nutrient supply across the Sandhill Wetland was most similar to the moderate-rich and saline fens except for sulfur supply, which was considerably elevated. Based on PRS probe and porewater observations, the Sandhill Wetland is not a eutrophic system in the sixth growing season, and supply for most nutrients are within the ranges of natural systems. However, effects from local atmospheric nitrogen deposition (reported up to 12 kg N ha-1 yr-1) could alter structure and function over subsequent growing seasons. Currently, ecosystem health and functionality of the belowground environment appears to be adequately restored at the reclamation site. Lastly, as no officially recognized protocols exist for evaluating performance of recently reclaimed wetlands constructed above open-pit mines, using the Sandhill Wetland as a test site I propose a framework for evaluating reclamation site performance. Although the proposed evaluation protocol does not rely on multivariate techniques, the performance evaluation results support the previous findings (that were based on multivariate analysis) that a marsh-like analogue is the most realistic reclamation outcome for the reclaimed Sandhill Wetland. While the reclamation has been highly successful in terms of creating a wetland that has persisted, future monitoring of water chemistry and plant community structure should continue at the Sandhill Wetland, to capture important successional changes that may occur as the site matures.

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