Water Crisis and Importance of Water Productivity in Agriculture in Dry Area of Iran (Case Study: Birjand Plain)

Water crisis is one of the basic environmental problems in the middle east. Many experts are worried about the use of limited water resources in Iran without considering the situation in future which will be a serious problem. The usage of aquifer is the source of social and economical activities in a large part of Iran. In several last decades population growth، agriculture and industrial development caused huge gap between out put and input in aquifer،due to this drought the gap has been deeped during last years. The south Khorasan province is one of the eastern province in Iran which has crisis in all section of its plain. Hence, it is important for preventing water shortage and deficiency to consider multipolicies especially for presence water resource usage. Water productivity in agriculture is one of the methods that can provide useful information for environmental policymakers and planners, for example، agriculture water resource managers. By considering water shortage in dry area، we can use the limited water supply for culturing plants that need less water and produce more output with more income. In arid area like south Khorasan which waters is exclusively provided from aquifer and by deep and semi- deep bore wells, therefore from water productivity in agriculture indexes we can use for better managements of culture patterns. This case was studied by estimated cost of agriculture products in area at west of Birjand plain. For this purpose we used the method of sampling at two stage. The number sampling question were 76 and question were about main agricultural producers of farmers. The data were analyzed by cost software. The result shows that cultivations with high water consumption and low income such as; sugar beet and alfa alfa must be eliminated and left out in pattern of cultivars, replaced by such cultivars as sorghum and/or annual rotation of some crops like wheat and millet which both bring about a reduction of water consumption and high economic profits for agriculture operators.