Keywords:  soil water balance, underground runoff, intensive filtration, duration of calculated interval, experimental fault

// Мелиорация. – 2017. – №2(80).– С. 5—9

Comparative analysis of soil moisture reserve measured in the field showed that soil water balance should be accounted for 24 hours to manage irrigation under changeable weather conditions. Only in this way the calculation error does not exceed the measurement accuracy of soil moisture reserves directly in the field and is equal approximately to the daily water consumption of the irrigated crop. If calculated interval is extended, the error in the water balance calculation will increase exponentially.