|Watts, Donald - Don|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 8/16/2004
Publication Date: 8/16/2004
Citation: Basta, N.T., Dayton, E.A., Novak, J.M., Moore Jr, P.A., Watts, D.W. 2004. Immobilization of phosphorus and manure using Al-based treatments and byproducts [abstract]. Proceedings of the 4th International Phosphorus Workshop, August 16-19, 2004, Wageningen, The Netherlands. 2004 CDROM.
Technical Abstract: Aluminum-based byproducts (WTR, drinking water treatment residuals treated with alum) have been shown to effectively reduce phosphorus (P) solubility and transport to surface and ground water. Several types of best management practices (BMPs) have been proposed to utilize WTR in efforts to reduce off-site P transport. Examples include surface applying WTRs in vegetative filter strips to reduce runoff P losses and incorporating WTR into high P soils allowing for reductions in extractable P concentrations. Reductions in extractable P concentration have been also demonstrated by mixing WTRs into organic amendments such as manures, biosolids, and compost. Although these studies have demonstrated effective reduction in off-site P movement and soil extractable P concentrations, widespread acceptance of WTRs as a BMP remains illusive due to the lack of long-term studies. Our objectives were to determine runoff P losses after alum-based WTRs were incorporated into a high P soil and to determine extractable P reductions from the high P soil and poultry litter treated with WTRs in long-term field and laboratory incubation studies. The six WTRs were mixed with soil (Mehlich 3 P conc. 315 mg/kg) at 0, 5, 10, and 20 Mg/ha and were mixed with poultry litter at 0, 10, 25, 50, and 75% (w/w). After incubation (between 21 and 90 days), simulated rainfall studies were conducted to determine soil runoff P losses and the WTR+ litter mixtures were extracted for P using Mehlich 3 reagent and 0.01M CaCl2. The WTRs incorporated into soil with high P concentrations caused a reduction in runoff P losses between 19 to 67% compared to controls. A significant reduction in extractable P (both Mehlich 3 and salt reagent) between 10 and 91% occurred after WTRs were blended with the high P soil and poultry litter. These studies show that WTR incorporation into material with high P contents can diminish runoff P losses and extractable P concentrations, thereby serving as a BMP to reduce non-point P pollution of ground and surface water bodies.