Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 11/11/2002
Publication Date: 11/11/2002
Citation: Lee, D.T., Clapp, C.E., Molina, J., Layese, M.F., Miller, M.A., Hayes, M., Baker, J.M. 2002. Modeling nitrogen transformations during a long-term incubation.. ASA-CSSA-SSSA Annual Meeting Abstracts. Paper No. S03-clapp123319-Poster.
Technical Abstract: Inorganic and organic N were determined on a Waukegan silt loam soil for a 90-wk aerobic incubation experiment. N-15 labeled soil samples were taken from 2 different tillage treatments (till, T or no-till, NT), and 2 residue management techniques (returned, R or harvested, NR). Triplicate samples of 4 treatment combinations were incubated in polyethylene bags at 35C under constant water conditions. NO3-N concentration was determined at periodic intervals after KCl extraction. Using a Mason jar diffusion technique, extracted samples were converted into NH4-N for total N and N-15 analyses. Atom % N-15 (inorganic) increased, reached a plateau, and then decreased. The extent of each phase depended on the treatment. This information was used to estimate the N-15 content in the organic pools of the model NCSOIL.