Research Activities

My research program focuses on the environmental impact of agricultural practices. Through the application of fundamental chemical and hydrological principles to soil systems, the long term goal is to increase soil productivity and minimize environmental pollution emanating from agricultural activities. My research interests include environmental impact of using synthetic fertilizers and animal manure as plant nutrient sources, transformations and mobility of phosphorus in soils and nutrient management for increased productivity.

Current Research

1.	Phosphorus release from soils under simulated spring snowmelt flooding

Phosphorus losses from agricultural soils to water bodies has a potential negative impact on the environment through promoting algal blooms in water bodies, a serious water quality challenge facing Lake Winnipeg. In the Canadian Prairies, most lands are poorly drained due to relatively flat landscapes and low-permeable soils, thus frequently leading to flooding during the snowmelt period. Prolonged flooding makes the soils anaerobic, a condition that can enhance P release from soils to overlying floodwater, increasing the risk of phosphorus loss to water bodies. We are investigating phosphorus release under temporarily water-logged conditions in the laboratory and in field using packed soil mesocosms and intact soil monoliths for different soil types in Manitoba under simulated summer and spring snowmelt flooding. Such information is needed to develop best management practices associated with surface and subsurface drainage, to reduce phosphorus mobilization from flooded soils with consequent occurrence of anoxic conditions.

Funding organizations: Natural Sciences and Engineering Research Council of Canada (NSERC) - Discovery grant. NSERC

2.	Soil amendments to reduce phosphorus losses from flooded soils in Manitoba

Soil amendments could play a role in reducing P release from flooded anoxic soils by enhancing P adsorption, and chemical precipitation. This research evaluates the effectiveness of different amendments such as calcium carbonate, gypsum, alum, magnesium sulfate, zeolite, ferric chloride and manganese oxide at varying application rates in reducing P losses to floodwater, by conducting laboratory and field microcosm studies using soils from flood-prone areas of the Red River Basin of Manitoba. Our results so far with packed soil mesocosms and intact monoliths in the laboratory and in field showed that application of gypsum, alum, ferric chloride and magnesium sulfate significantly reduced floodwater dissolved reactive P concentration compared to unamended soil.

Funding organizations: Environment and Climate Change Canada through Lake Winnipeg Basin Program, Lake Winnipeg Foundation, University of Winnipeg Major grant, Queen Elizabeth II Diamond Jubilee Advanced Scholar Program NSERC Grant Lake Winnipeg Foundation (PDF)

3.	Urease inhibitors to reduce ammonia volatilization losses from urea

Urea and urea-based fertilizers are the dominant sources of commercial nitrogen (N) fertilizers worldwide. A large portion of the applied N from urea-based fertilizers is lost in form of ammonia volatilization within about two weeks of application because of the rapid hydrolysis of urea by the urease enzyme. This process is one of the reasons why the efficiency of N fertilizer is low. Urease inhibitors have been reported to conserve urea-based N fertilizers by reducing N losses. We evaluated a new formulation of a urease inhibitor in the laboratory, greenhouse, and in field. The results showed that the new formulation reduced ammonia volatilization even at a low concentration, and with a greater effectiveness when fertilizer was fall-applied than spring-applied.

Funding organizations: Natural Sciences and Engineering Research Council of Canada (NSERC) – Collaborative Research and Development grant, Active AgriScience Inc