Irrigation water from King Abdullah Canal (KAC) was used for soil leaching. Five pore volumes (PV) were
allowed to pass through soil columns and leachates were collected in successive 30 mL aliquots. The PV is the
volume of water required to saturate all soil pores. Average PV was about 460 mL, average porosity was 0.48, and flow
velocity ranged 2.2–2.4 cm h-1. The experiment was terminated when salinity (EC) of effluent approached that of
canal water. Soil samples were taken out from columns, dried and analyzed for EC, pH, exchangeable Na, Ca, Mg,
and K. Moreover, in separate column experiments a known PV was added to each packed column (e.g. 1 PV), then the
leachate was collected once. After that soils were taken out and analyzed for exchangeable Na and ECe. Data per each
percolated PV (exchangeable Na and ECe) were graphed against PV.