Submitted to: American Society of Agricultural and Biological Engineers
Publication Type: Abstract Only
Publication Acceptance Date: December 7, 2009
Publication Date: June 23, 2010
Citation: Feyereisen, G.W., Kleinman, P.J., Folmar, G.J., Saporito, L.S., Allen, A.L. 2010. A Phosphorus Transport Study: Influence of Poultry Litter Application Method on Leaching [abstract]. American Society of Agricultural and Biological Engineers. Paper No. 1009193. Technical Abstract: Phosphorus (P) transport to surface waters via subsurface pathways contributes to eutrophication. This study was conducted to compare the extent and mechanism of vertical P translocation after application of poultry litter by broadcast, broadcast-then-disked, and subsurface banding/incorporation methods to a high-P content (500+ mg/kg Mehlich3-P) Atlantic Coastal Plain soil on the University of Maryland-Eastern Shore Research Farm near Princess Anne, MD. Treatment and unamended control replicates were collected from the field in undisturbed soil blocks 61 by 61 by 61 cm and prepared for two rainfall simulation events that were separated by 11 semi-weekly soaking-type irrigation events. After the simulation regime, FD&C No. 2 blue food dye was applied to the soil surface and leached through the profile. The blocks were inverted and the soil was removed in 10-cm layers, beginning with a layer at 50-cm depth. Separate soil samples were taken around the dye-stained surface of macropores and within the soil matrix, and analyzed for P content. Calcium chloride-extractable P (CCEP) levels for the soil associated with macropores were significantly elevated over the soil matrix within treatment, at the 30-cm depth, for all manured treatments, but not for the control, confirming that macropores are a pathway for translocation of recently applied litter P. Among treatments, macropore CCEP levels at the 30 and 40-cm depths were greater for the broadcast treatment than for the other litter application treatments, whose methods involved soil disturbance. Interestingly, CCEP concentrations in the soil matrix at the 30-cm depth were significantly higher for the unamended control, suggesting that matrix flow P losses from these high-P content soils will continue after cessation of litter application.