Many agricultural soils in southeastern Manitoba have a history of hog manure application and this survey was intended to compare their nutrient status with similar soils that have not received manure. The land areas that were studied were characterized by coarse textured, low agricultural capability soils in grass forage production. The study locations are considered representative of soil landscapes commonly known as the Poppleton, Pelan and Malonton soil associations. The study found that there was a higher concentration of nitrogen and phosphorus to a depth of sixty centimeters in manured fields, especially for phosphorus when compared to non-manured fields. However, at some of the non-manured sites there was evidence of elevated nitrogen and phosphorus levels that were lower than the manured sites. The importance of keeping good production records of cultural, nutrient and manure management practices are essential in providing information for relating residual nutrient levels to nutrient balances of applied organic and inorganic fertilizers. The data showed that the variability in nitrate nitrogen and phosphorus status was greater between fields than within fields, particularly for nitrogen status whether the fields were manured or non-manured. The highest concentrations of nitrogen and phosphorous were found at the soil surface (0-6 inches) with nutrient levels decreasing with depth. In some cases concentrations of nitrogen and phosphorus were observed below the 0-6 inches depth and in some cases they were not. Deep sampling also showed concentration of nutrients below 2 feet in some cases. As with any addition of nutrients there are potential risks to runoff and surface water contamination or leaching and groundwater contamination. Soluble nutrients that are in excess of crop requirements present a greater risk of being transported to water through runoff or leaching, particularly where the soil types are characterized by coarse textures and rapid permeability. Water table depths were found to vary more between locations than within each location. At the manured locations water table depths ranged from one to two feet to greater than nine feet. Depth to water table at the non-manured locations ranged from two to three feet to greater than nine feet from the ground surface.
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