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Canada has large reserves of heavy oil stored in the form of oil sands in the Athabasca region. This type of heavy oil does not flow at room temperature and its agglomeration with sand complicates its extraction. Consequently, extraction of the oil is costly and remains challenging. This project aims to use a temperature-responsive polymeric surfactant (TRPS) to improve the extraction of oil. The temperature-responsive polymeric surfactant (TRPS) poly(ethylene glycol)-b-poly[2-(2-methoxyethoxy) ethyl methacrylate] (PEG-b-PMEO2MA) was successfully prepared by atom transfer radical polymerization (ATRP) and its efficacy at extracting oil from oil sands was investigated. First, several PEG-b-PMEO2MA samples were synthesized having an absolute molecular weight ranging from 17,000 to 20,000 g/mol as determined by NMR and an apparent PDI ranging from 1.1 to 1.5 as determined by GPC analysis. Then, the lower critical solution temperature (LCST) was found to equal 34 ?? 1??C for all samples by turbidity measurements. The PEG113-b-PMEO2MA64 micelles in aqueous solution, whose hydrodynamic diameter (dh) determined by dynamic light scattering (DLS) equaled 26.3 ?? 0.3 nm, had an aggregation number (Nagg) of 100 ?? 8. After characterization of this TRPS, PEG-b-PMEO2MA was used for oil extraction and showed promising results. With the addition of 60 to 65 mg of toluene on top of 15 mL of a 1 mg/mL PEG-b-PMEO2MA aqueous solution, complete oil recovery could be achieved by putting the TRPS solution with 1 g of oil sands in a shaker at 45 or 50 ??C for 24 hrs. In addition, a time-dependent oil extraction experiment showed that by using a 1 mg/mL TRPS aqueous solution, 100% oil recovery was reached after only 6 hrs. Furthermore, the PEG-b-PMEO2MA aqueous solution could be recycled for several oil extraction cycles while still maintaining a high oil recovery.

A concern with organic farming is for the depletion of soil phosphorus. The objectives of this study were to determine which organic management systems deplete soil phosphorus and whether arbuscular mycorrhizal fungi (AMF) could assist crops in taking up phosphorus in these systems. The research site was a 14 year-old study at Glenlea, Manitoba, having 3 different 4-year rotations under organic and conventional management: forage-grain ± manure-compost, grain-only, and a restored tall grass prairie. The modified Hedley procedure revealed organic systems to have lower concentrations of labile phosphorus than conventional but recalcitrant fractions did not differ (P < 0.05). Nitrogen was limiting in the organic grain-only rotation; phosphorus in the organic forage-grain. Mycorrhizal colonization as arbuscules was higher in organic than conventional systems (P < 0.05). To prevent phosphorus limitation, we suggest high-export organic rotations be balanced with sufficient rates of manure-compost and AMF maintained to help with phosphorus absorption.

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