Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 11/4/1999
Publication Date: N/A
Citation: Logsdon, S.D., Keller, K., Moorman, T.B. 1999. Input parameter measurement for macro, a two-flow domain solute transport model. Agronomy Abstracts. CD-ROM. Madison, Wisconsin.
Technical Abstract: The model MACRO can separately simulate reactive and nonreactive solute and tritium leaching, and can include preferential flow, anion exclusion, as well as field and crop conditions, but considerable input is necessary. The objective of this study was to compare the model MACRO with laboratory column leaching data of bromide and tritium, using measured inputs where possible. We collected undisturbed columns from three soils, each from no-till and chisel plots. Bromide was dripped unto the columns 3 d before the tritium was added in the first rainwater, with untritiated water for the last three rains. Each rain was 30 mm, with half of the columns receiving a high intensity for the first rain, and the other half receiving a high intensity for the last rain. Extra columns were used for determining soil properties. When the model was calibrated to fit tritium leaching, the predicted results did not fit bromide leaching, even when anion exclusion zones were assumed. We discuss possible techniques to measure input parameters.