Determining the Most Effective Agricultural Technologies in Actual Water Saving in Three Watersheds

In the current research, with the aim of identifying the most effective techniques to reduce actual water use (Eta) to help restore the lakes of Urmia, Tashk-Bakhtegan, Fars, and Shadgan Wetland in Khuzestan, monitoring was carried out in the crop year 2021-2022 by applying planting techniques at the level of farmers' fields and orchards. In this research, 55, 17, and 18 farms and orchards were considered from Urmia Lake, Tashk-Bakhtegan and Maron-Jarhari basins, respectively. The results showed that the application of all techniques reduced irrigation water by an average of 24.6%, increased yield by an average of 18.3% and water productivity by an average of 60.4% for all the three catchments. However, not all these techniques were effective in reducing the amount of ETa. Farm monitoring showed that the techniques based on "accurate scheduling based on soil and plant indexes along with the modification and optimal management of the existing irrigation system" were able to reduce ETa by an average of 15.5% and improving the efficiency of water productivity (WPET) by an average of 40% in all the three basins. Therefore, the most effective techniques in Urmia Lake basin were use of two-way furrows of rows of trees in surface irrigation and planning drip irrigation based on soil and plant indexes in row crops and trees, which reduced ETa by 18%. Also, there was 21%, reduction in ETa by making irrigation plots under tree shades for pomegranate and pistachio in the Tashk-Bakhtgan Basin, and 13% reduction by making basins around the shading surface of palm trees along with palm leaf mulch, and 14 % reduction by the water flow cutback management method in the strip surface irrigation in the Maron-Jarahi Basin. These were considered as the most important techniques. Finally, it can be stated that paying attention to monitoring techniques at the level of a basin with local participation and promoting them can be effective in protecting the region's ecosystem while establishing sustainable agriculture.