Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: July 15, 1998
Publication Date: N/A
Technical Abstract: The phosphorus (P) distribution forms in soil, ground water, and stream water were evaluated to determine if P was accumulating and moving through soil in a North Carolina spray field that has received intensive swine manure application (95 kg P/ha/yr) for 11 years. Soil, which has received no manure, had low concentrations of Mehlich 3 P (M3P = 1.5 to 4 [mu]g P/g) in the profile (0 to 183 cm deep). In contrast, a spray field survey showed that surface (0- to 15-cm) and subsurface (45- to 90-cm) soil had mean M3P concentrations of 353 and 140 ([mu]g P/g), respectively. Spray field ground water wells initially had low concentrations of o-P (<40 [mu]g P/L), but after eight years of manure application, some well concentrations rose to 50 to 450 [mu]g P/L. An adjacent stream was low in o-P (<45[mu]g P/L). Results indicate that plant available P has accumulated in surface and subsurface soil and that ground water in the field was enriched in o-P. Phosphorus enrichment of a stream draining the spray field was minimal, indicating limited impact by P from the swine manure.