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 ...

monthly discharge is one of the most important factors considered in designs and hydrological works. some watersheds are not equipped with needed hydrometric equipment. in such a case average monthly discharge could be estimated from regional monthly water balance models of representative watersheds. in this study, thornthwaite & mather (tm) model were used in the pishkouh watershed in arid...

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...

recent droughts and indiscriminate use of ground water for agriculture, is the main problems of the especially desert country.water crisis has gripped all of country plains, and due tothe reduction of surface water resources and successive droughts, illegal exploitation of ground water resources is increasing.the knowledge of the water balance plains can be helped in the water resources managem...

limitation of water resources in iran motivates sustaining and preserving of the resources in order to supply future water needs. fulfilling these objectives will not be possible unless having accurate water balance of watersheds. the purpose of this study is to estimate the water balance parameters using a distributed method. the large number of distributed models and methods was studied and “...