Time series modeling for predicting spatially variable infiltration

Furrow irrigation performance is affected by spatial variability of infiltr ation; thus, its characterization is essential for accurate performance eva luation. A time-series modeling approach was used to characterize the spati al and temporal correlation structure of field-measured infiltration data. The time-series analysis indicated minimal spatial correlation of infiltrat ion characteristics along the furrow for the space intervals used (5 m). Th e time-series analysis led to a strategy by which relationships between inf iltration characteristics at short- and long-intake opportunity times for a limited number of infiltration tests could be used to "extend" infiltratio n information gathered by doing shorter duration tests at other furrow loca tions.