Effects of Using Sub-surface Drip Irrigation and ET-HSModel to Increasing WUE in Irrigation of Some Crops

摘要

Increasing of Water Use Efficiency (WUE) is a fundamental remedy tofood production under conditions of water scarcity. The aim of this study was toevaluate the potential for water saving and yield improvements with use of ET-HSmodel and subsurface drip irrigation. For this purpose, four irrigation treatments wereinstalled in a silty loam soil at an experimental farm near Isfahan city of Iran in 2000and 2001.The treatments included: Surface drip irrigation (DI), Sub surface dripirrigation in 15 cm depth (SDI15), Sub surface drip irrigation in 30 cm depth (SDI30),Furrow irrigation (FI). These treatments were repeated for potato in two genus ofMarfona and Navita (which they are ordinary genus potato in Isfahan region), tomatoand eggplant. In this research, a randomized complete block design of threereplications was employed for each crop. Also, in all of these treatments, crops waterrequirement and time irrigation scheduling were determined by ET-HS model. Forthis purpose, maximum and minimum temperature were measured daily and filled inthe model. Based on the results of this research, SDI15 has the most efficient use ofwater in the production and it is substantially different from other treatments, whichwere about 7.84, 3.84, 13.15 and 11.64 kg/m3 in Marfona, Navita, tomato andeggplant respectively. Also, results show that the highest yield was obtained fromSDI15 in Marfona, Navita and eggplant and from DI and SDI15 in tomato. A part ofthis increasing yield in SDI15 was related to better soil moisture in the root zone, lesswater runoff and less surface evaporation. Additionally, the results showed highreduction surface evaporation was obtained in SDI treatments. Finally, it can beconcluded that the subsurface drip irrigation, with drippers installed at a depth of15cm, and implementation of ET-HS model for estimating irrigation scheduling, is thebest condition for Moefona, Navita, tomato and eggplant.