Phosphorus Losses in Simulated Rainfall Runoff from Manured Soils of Alberta

• Published in: Journal of environmental quality Vol. 36; no. 3; pp. 730 - 741
• Main Authors: Volf, C.A, Ontkean, G.R, Bennett, D.R, Chanasyk, D.S, Miller, J.J
• Format: Journal Article
• Language: English
• Published: Madison American Society of Agronomy, Crop Science Society of America, Soil Science Society 01.05.2007; American Society of Agronomy
• Subjects: Agricultural land; agricultural runoff; agricultural soils; Alberta; Animals; Beef cattle; Cattle; Cattle manure; Conservation of Natural Resources; discing; fertilizer rates; Fertilizers; hydrology; losses from soil; Manure; Manures; Moisture content; Nutrient loss; Nutrient requirements; Nutrient uptake; Phosphorus; Phosphorus - chemistry; Rain; rainfall simulation; Rainfall-runoff relationships; Rural development; Simulated rainfall; Simulation; Soil - analysis; Soil amendment; soil amendments; soil chemistry; Soil testing; Studies; Surface water; Tillage; Water Pollution; Alberta; Alberta Canada; Canada; Canada, Alberta
• ISSN: 0047-2425; 1537-2537
• DOI: 10.2134/jeq2006.0269

Manure applied to agricultural land at rates that exceed annual crop nutrient requirements can be a source of phosphorus in runoff. Manure incorporation is often recommended to reduce phosphorus losses in runoff. A small plot rainfall simulation study was conducted at three sites in Alberta to evaluate the effects of manure rate and incorporation on phosphorus losses. Treatments consisted of three solid beef cattle manure application rates (50, 100, and 200 kg ha-1 total phosphorus), an unmanured control, and two incorporation methods (nonincorporated and incorporated with one pass of a double disk). Simulated rain was applied to soils with freshly applied and residual (1 yr after application) manure at 70 mm h-1 to produce 30 min of runoff. Soil test phosphorus (STP), total phosphorus (TP), and dissolved reactive phosphorus (DRP) concentrations in runoff increased with manure rate for fresh and residual manure. Initial abstraction and runoff volumes did not change with manure rate. Initial abstraction, runoff volumes, and phosphorus concentrations did not change with manure incorporation at Lacombe and Wilson, but initial abstraction volumes increased and runoff volumes and phosphorus concentrations decreased with incorporation of fresh manure at Beaverlodge. Phosphorus losses in runoff were directly related to phosphorus additions. Extraction coefficients (slopes of the regression lines) for the linear relationships between residual manure STP and phosphorus in runoff were 0.007 to 0.015 for runoff TP and 0.006 to 0.013 for runoff DRP. While incorporation of manure with a double disk had no significant effect on phosphorus losses in runoff from manure-amended soils 1 yr after application, incorporation of manure is still recommended to control nitrogen losses, improve crop nutrient uptake, and potentially reduce odor concerns.