Phosphorus transformation and transport from fertilizers and manures

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Lake Winnipeg is the 10th largest body of freshwater and the third largest reservoir of hydroelectric in the world. However, its health is currently threatened by excess nutrient loading particularly phosphorus (P). There is an urgent need to better understand the nature of phosphorus and how it is transformed in Manitoba soils to aid in developing practices that effectively reduce the movement of P from soil to surface waters. My research program investigates the transport and transformation of P in soil following additions of fertilizers and manures. I have proposed a series of studies on both fertilizer and manure P that will address some of the environmental and agronomic challenges of managing P in Manitoba. In the area of agronomy, the long-term objective of my studies is to significantly increase the efficiency of fertilizer P uptake by the crop. To achieve this objective, I will conduct studies to quantify and identify P minerals that are formed when non-phosphate salts are added to P fertilizer in dual bands. This information will help us to find the right formula for improving the fertilizer use efficiency of P by the crop. An increase in P fertilizer use efficiency will provide economic and environmental benefits to Canadian farmers through reduced input cost and reduced residual soil P. In the area of environment, the goal is to reduce P loading to the soil by examining the use of technologies such as phytase enzyme, highly available P grains (e.g. HAP Barley) and solid-liquid separation on manure and their effects on the forms of manure P and its solubility in the soil. This will ensure that management options for reducing manure P levels do not lead to the environmental problem of increased P solubility. I will collaborate with engineers on solid-liquid separation and its potential to reduce P loading to the soil. Results from this study will assist us develop commercial-scale system for effective removal of solids and P from swine manure. If the P rich solids can the separated then the liquid can be used near swine barns to provide nitrogen and the P-rich solid can be transported further away to serve as P source to crop elsewhere. This will address the issue of excessive P loading in the vicinity of hog barns and in regions with high animal density.