Title: Soil Phosphorus Dynamics in Response to Poultry Manure Amendment Authors
Submitted to: Soil Science Society of America Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: August 13, 2007
Publication Date: November 4, 2007
Citation: Waldrip Dail, H.M., He, Z., Erich, M., Honeycutt, C.W. 2007. Soil Phosphorus Dynamics in Response to Poultry Manure Amendment. Soil Science Society of America Annual Meeting. CD-ROM Technical Abstract: Increased understanding of the fate of manure P after soil application is needed to effectively utilize manure to its full fertilization potential. To determine the short-term effects of manure amendment on soil P distribution, we aerobically incubated two Maine soils with 0, 100, or 200 mg P kg-1 of litter-free layer hen manure at 25oC for 108 days. Interchanges among P species were characterized using sequential fractionation with H2O, 0.5 M NaHCO3, 0.1 M NaOH, and 1.0 M HCl followed by phosphatase hydrolysis. Amendment with poultry manure had a similar effect on both soils; however, the soil P level was amplified in the soil with greater sand content. Water soluble Pi in amended soils initially increased, but later declined to control levels. Changes in NaHCO3, NaOH, and HCl fractions were similar for both amended and unamended soils, reflecting the importance of soil properties in controlling P dynamics. A decrease in NaHCO3-Pi along with a simultaneous increase in NaOH-Pi at Day 84, implied transformation of P from one fraction to the other. Addition of 200 mg P kg-1 poultry litter increased HCl-extractable P from both the inorganic and organic fractions. Enzymatically hydrolysable organic P changed very little following poultry manure addition, as the majority of organic P from poultry manure was non-hydrolysable. These results suggest that soil properties, including texture, are primarily responsible for controlling P distribution in soils amended with poultry manure and that the majority of amended P is in forms considered relatively unavailable for plant uptake.