Effect of Irrigation Water Salinity on Soil Chemical Characteristics under Drip Irrigation System (T-Tape)

To study the effect of irrigation water salinity on soil chemical characteristics¡ a randomized complete block design experiment was conducted with four treatments of irrigation water salinities of 2¡ 6¡ 9 and 12 dS/m with three replications for each treatment in a corn field under drip irrigation system (T-Tape). The study was carried out in an arid region with high initial soil salinity and soil texture of loam. Results of soil chemical analysis from different soil depths of 0-30¡ 30-60 and 60-90 cm showed that in each layer of soil with increase in irrigation water salinity the salinity of soil saturated extract increases and the salinity of soil saturated extract in deeper layers was higher than upper layers. During the growing season¡ for each of three soil layer profiles¡ with uniform irrigation with water salinity of 1dS/m the value of the ECe¡ SAR¡ HCO3¡ Cl and ESP were decreased. However¡ irrigating with different irrigation water salinities caused that the above values increase after the crop stage of four leaf corn and the maximum increase occurred at the end of growing season. In regions with lack of fresh water¡ irrigating with saline water under drip irrigation will result in uniform distribution of water and soil salinity in soil profile.