Agricultural runoff modeling in a small west Tennessee watershed

The application of hydrological Simulation Program in FORTRAN (HSPF) to agriculture runoff was examined. An 18 hectare watershed planted in corn was secured along its perimeter and all runoff from the conventionally tilled field was directed to a single discharge structure equipped with an H-flume, continuous flow recorder, and automatic sampling equipment. Data on runoff, suspended solids, nitrogen forms, and atrazine over a 19-month period were used to develop a preliminary calibration of the model. Simulation of runoff and sediment was generally good, while simulation of atrazine and soluble nitrogen forms was fair