Trickle irrigation soil water potential as influenced by management of highly saline water

The objective of this investigation was to determine experimentally the soil water potential and salt patterns in uniform soil profiles as a result of four different water management treatments. Under these treatments cherry tomato plants were irrigated (a) daily with a volume of water equal to that used by the plant on the previous day, (b) every other day with volumes of water equal, (c) below, and (d) above the water evapotranspired. In general, the soil water potential decreased in the soil profile, as a result of salt accumulation, with increased distance from the trickle source. In the profiles where the wetting fronts reached the mid-region between the emitters much lower soil water potentials were measured near the soil surface. The highest salt concentration occurred in the profiles irrigated with volumes of water below that evapotranspired by the tomato plants, indicating the importance of avoiding underirrigation whenever highly saline water is used with trickle irrigation. Higher soil water potentials and higher yields resulted from irrigating with volumes above the evapotranspiration.