Irrigation Management under Saline Conditions Using Wetting Front Detector (WFD)

Determination of drainage water salinity can be a useful tool for precise soil salinity control. On the other hand, leaching fraction under steady state conditions can be estimated simply by knowing drainage water salinity. But, when drainage facilities are not installed, drainage water is not available conveniently. A device called "Wetting Front Detector" has provided this possibility using no electrical or mechanical device. In this research, actual drainage water salinity and leaching fraction was directly measured by installing this device in irrigated pistachio orchards of north Ardakan, in southern parts of the Iranian Central Plateau. The measured data were used as entries for simulation models to estimate mean root zone salinity. Estimates of the models were compared with the measured mean root zone salinity. Leaching fraction was estimated to be about 40% using this approach and measured mean soil salinity was generally between approximated values using two models. There was also a fair correlation between the actual measured values and the estimated factors using the two models.