Wednesday, November 15, 2006

Field measurement results versus DAYCENT simulations in nitrous oxide emission from agricultural soil in Central Iowa.

Marek K. Jarecki1, Tim B. Parkin2, Al S.K. Chan3, Tom C. Kaspar2, Jerry L. Hatfield2, and Ray A. Jones4. (1) AgCert, National Soil Tilth Lab., 2150 Pammel Drive, Ames, IA 50011-4420, (2) National Soil Tilth Lab., 2150 Pammel Dr., Ames, IA 50011-4420, (3) AgCert, 1901 S. Harbour City Blvd. Suite 400, Melbourne, FL 32901, (4) AgCert Canada, Manulife Place, 10180 101 Street, Suite 100, Edmonton, AB T5J 3S4, Canada

Nitrous oxide emissions measured from corn-soybean rotations in Central Iowa were compared with the results obtained from DAYCENT simulations. Available whole year emission field data taken weekly during the growing season and monthly during the winter time, were used. DAYCENT simulations were performed using the field soil, management and weather conditions as input variables. Daily and cumulative emission predicted by DAYCENT in several cases differed significantly from the results obtained from field measurements.