abstarct precise knowledge of all components of water balance is essential to optimize water use in irrigated agriculture. however, water balance components are difficult to measure in required time intervals because their measuring is time consuming and costly. unsaturated zone simulator models are useful tools for predicting the effects of agricultural management on crop water use and can be ...

evaporation from the soil surface has an important role in the water balance model in nature, so that the major part of rain fall and irrigation water in arid and semi-arid regions is lost via evaporation from the soil surface. in such areas, there are some regions with high water table and because of evaporation from the soil surface, salts accumulation also occur in the soil surface. so evapo...